e =^ > z < n o u LiJ Dl UJ IT M z CORNELL UNIVERSITY LIBRARY Given to the COLLEGE OF ENGINe-EI^IN sorber — Operation of the Plant. The general construction of the "American" ah- sorption refrigerating machine is of the straight pipe type, as far as possible eliminating round and bent pipe coils. There are no movable parts except the aqua ammonia pump. No oil is required except the pmall amount necessary for lubricating the movable parts of this pump. FIG. 20. — AMERICAN ABSORPTION MACHINE SHOWING PRINCIPAL PARTS. The principal parts of the machine are shown in the diagram, Fig. 20, and consist of absorber, ammo- nia pump, generator, exchanger, dehydrator, weak liquor cooler, condenser, expansion coils and ammonia regulator. 70 THE ABSORPTION REFRIGERATING MACHINE In operation the aqua ammonia, or strong liquor, is pumped from the absorber into the generator, pass- ing on the way through the exchanger or equalizer where it is partly heated by the returning hot weak liquor from the generator. The generator is a heavy vertical cast iron cylinder or cylinders, the number de- pending upon the capacity of the machine, which form a part of the apparatus. On top of the vertical tube, a standpipe is mounted, the top section of which con- tains the rectifier coils and immediately below these are the analyzer pans. The rectifier consists of a number of straight pipes through which the strong ammonia liquor, which is forced in at the top, passes on its way to the evaporat- ing coils of the generator. In going down the rectifier pipes the cold strong liquor is surrounded by the hot gas rising from the evaporating pipes of the generator, cooling this gas and causing the moisture rising with it to condense upon the cold surfaces of the rectifier pipes and flow by gravity to the analyzer. The analyzer consists of a number of perforated east iron pans of varying sizes down through and over which 4he strong ammonia liquor is precipitated. The stream of aqua being thus finely divided, rapidly ab- sorbs heat from the rising ammonia gas, so that it en- ters the evaporating cylinders of the generator at a temperature which greatly expedites evaporation. The evaporating cylinders of the generator contain coils of extra heavy pipe through which steam is cir- culated and around which the strong, already partly heated, aqua ammonia flows. The heat of the steam quickly drives off from the strong liquor, the major portion of the contained gas, which rises upward through the standpipe and around the analyzer pans and rectifier coils as already explained. THE ABSOKPTION REFHIQEKATING MACHINE 71 After passing the rectifier, however, the gas still holds entrained some moisture and in order to remove this, the gas is passed through the dehydrator. The dehydrator is of the horizontal shell type, and contains a coil through which the cold aqua ammonia from the absorber is passed on its way to the generator. Around this coil is a large pipe or shell supported by baffle plates. This larger pipe or shell is set in a steel trough where it is cooled by a portion of the waste water from the condensers. The flow of gas from the generator passing through the dehydrator is retarded by the baffle plates and cooled by the cold surfaces of the rich liquor coils and the cold walls of the shell, causing the moisture to precipitate. The moisture flows by gravity to the generator and the gas, now freed from moisture, passes on to the condenser where it is liquefied. The steam after it has served its purpose in the generator is condensed and used to fill the ice cans, in the case of ice making plants; but in refrigerating plants it is trapped back automatically to the boiler as boiler feed. The ammonia condensers are made either of the double-pipe type or of the submerged or atmospheric types. The weak liquor cooler is constructed like the double-pipe ammonia condenser of small inner pipes enclosed in larger outside pipes, the weak liquor flow- ing through the inner pipes and the cooling water through the annular space between the inner and outer pipes. The exchanger or equalizer is of the double coil type. It is built of extra heavy pipe and fitted with extra heavy headers and return bends and arranged so as to allow a counter-current circulation through both pipes at the same time. The cool aqua drawn 72 THE ABSOEPTION KEFRIQEHATING MACHINE from the absorber is forced under pressure through the inner pipe of the exchanger and the hot weak liquor from the generator, also under relatively high pressure, passes through the annular space between the pipes the two currents running counter to one another ex- changing temperatures. The hot weak liquor thus part- ly cooled passes from here to the weak liquor cooler. The ammonia pump is of heavy double fly-wheel type made to run at a speed of about twenty-five revo- lutions per minute. The stuffing box on the ammonia cylinder is set in a water chamber, so that the water surrounding the piston rod furnishes constant lubrica- tion and prevents leakage of ammonia through stuffing box. The absorber is of the vertical type, made of boiler steel and is fitted with small straight tubes in place of coils; the tubes ordinarily used are of 1% inch diameter and galvanized. When the liquefied ammonia from the ammonia condenser and liquor receiver, has accomplished its refrigerating service in the expansion coils, it is passed to the absorber, where it unites with or is absorbed by the weak liquor flowing from the weak liquor cooler and forms strong ammonia liquor to be used over again in the generator, dehydrator and condenser and evaporator as before. Much lower temperatures are obtained with an ab- sorption machine because of the fact that lower back (or suction) pressure is maintained by the aid of the absorber. Zero back pressure can be maintained as readily as 15 pounds back pressure, and since am- monia at pounds back pressure boils at 29 degrees below zero, a much lower cooling effect is obtained than is possible at 15 pounds back pressure at which point ammonia boils at 1 degree above zero; a dif- ference of 28 degrees in favor of the lower back pres- sure, which can be maintained very economically by THE ABSORPTION HEFBIGERATING MACHINE 73 the absorption machine, and is a great advantage over other types of machines. Cooling water enters the absorber at the bottom and flows through the small straight tubes to the top where it overflows. The weak liquor enters the ab- sorber at the top as does also the gas. In order to control the flow of weak liquor coming from the gen- erator, through the exchanger and weak liquor cooler, a special patented automatic ammonia regulator is connected to the absorber. In ordinary operation the weak liquor leaves the generator at a pressure of approximately 150 pounds, while the gas admitted to the absorber is under a pressure varying from five to fifteen pounds. The re- turning weak liquor will absorb from 27% to 29% of its weight of ammonia gas, but in order to accom- plish this it is essehtial that the pressure of the in- coming fluid and that of the incoming gas be equal. This is automatically performed in the regulator by means of a float valve and float chamber, attached to and connected by a pipe with the interior of the ab- sorber. When the flow of weak liquor into absorber reaches a height where the pressure exceeds that of the incoming gas, the float is raised and shuts off the supply. When the float descends the liquid admission valve opens. The regulator can be adjusted so as to carry the required height of liquid in absorber and generator for most efficient operation. The adjust- ment can be done while the machine is in full opera- tion and without disconnecting any parts. 74 THE ABSOEPTION REFRIQEEATING MACHINE CHAPTER XII. How Refrigerating Machines Work — ^Description of the Car- bondale Machine, Including the Tubular System, and the Atmospheric System — Type to Use — ^Advantages. The cooling effect in refrigerating machines is pro- duced by the evaporation of ammonia or some other substance. Ammonia gas can be liquefied in a con- denser, or cylinder, if subjected to a pressure of from 100 to 200 lbs. per square inch while cooled to about 70° F. by water cooling coils. This liquid flows through a throttling valve into a vessel, or cooler, at much lower pressure, where brine, or some substance inside pipe coils, is cooled by this evaporating liquid, which must be redelivered to the condenser under pres- sure to be once more condensed by cooling water so it can expand again. Thus the same ammonia is con- stantly used over and over again. There are two methods of drawing the gas out of the cooler and delivering it under pressure into the condenser, the compression and the absorption systems. In the compression system a compressor, or gas pump, can be used to draw the ammonia gas out of the cooler and pump it into the condenser and this system is therefore composed of four main parts : Compressor. Engine to drive compressor. Condenser cooled by water coils. Cooler warmed by brine coils (that is, the brine is cooled by the ammonia). In the absorption system the ammonia gas is drawn THE ABSORPTION REFEIGEnATINO MACHINE 75 out of the cooler by the absorbing action in the ab- sorber where the gas meets weak aqua ammonia which flows over from the generator, dissolving this gas and making strong liquor, which is pumped by an aqua pump into a generator or still, where the solution is heated by steam, and the gas is driven o£E under pres- sure into the condenser, where it is liquefied the same as in the compression system, and from whence it ex- pands into a cooler to produce the cold again. The Carbondale absorption system consists of the following principal parts: Generator with steam coils for driving off gas un- der pressure. Condenser with water cooling coils to liquefy gas coming from the generator. Cooler with brine coils. Absorber, where the liquor flowing over from the generator absorbs the gas coming from the cooler, form- ing a strong solution. Ammonia pump to pump this strong solution back into the generator to be redistilled. Exchanger, to cool the weak liquor flowing from the generator to the absorber by the cold strong liquor pumped from the absorber to the generator. Water will absorb 1,000 times its volume of am- monia gas, hence a very small aqua pump is required, in fact a compressor to handle the gas (without first dissolving it in water) must be about 80 times as'large. Heat is needed in the generator to distill off the ammonia, but any waste heat like exhaust steam can be used, while the compression system requires power from a steam engine, gas engine, electric motor, etc. The absorption system cannot be run by mechanical power and hence cannot be operated by electricity, but there is an enormous field for it in utilizing waste heat. 76 THE ABSORPTION REFEIGEEATING MACHINE CONSTRUCTION OF PARTS. The Carbondale Absorption Eefrigerating and Ice Making Machine can be operated by either live or ex- haust steam or waste heat, 212° or hotter, and the various parts are constructed as follows: The generator is of steel or cast-iron, fitted with steam coils. The rectifier is a coil with patent drips for draining off the moisture and is cooled in a tank of water (sub- merged type), or by water trickling over it (atmos- pheric type). FIG. 21.— CARBONDALE MACHINE — ATMOSPHERIC CONSTRUCTION. The exchanger consists of a cylinder filled with helical coils or is double tube type (one pipe inside another) . The condenser is of the Carbondale shell type (a cylinder filled with coils), or double tube, or atmos- pheric type. The absorber is either the shell and coil type, or horizontal straight tube type, or atmospheric type. THE ABSOnPTION REFKIGEKATINO MACHl.VE 77 78 THE ABSORPTION REFRIGERATING MACHINE The cooler is of the Carbondale shell type, or dou- ble tube type. The ammonia pump is driven by electric motor, belt or steam. Pig. 31 shows the atmospheric type of absorption machine, and Pig. 22 shows the tubular type of absorption machine. METHOD OF OPERATION OF CARBONDALB MACHINE. Aqua ammonia, such as can be bought from chem- ical houses in drums, is put in a horizontal generator, generally pumped in with the aqua ammonia pump after the machine is connected and tight, and this aqua is heated with steam coils to about 220° P., more or less, at which temperature the ammonia gas is driven ofE and the pressure gradually rises until it reaches about 150 pounds pressure per square inch when it starts to condense in the condenser. If the condenser is of sufficient capacity and the gas is well cooled with the water coils, it is impossible to raise the pressure much above this liquefying point, even though the gen- erator is heated with the steam as hot as possible to force the distillation. This gas leaving the generator, passes through the analyzer trays where some of the entrained moisture is deposited and then passes through the rectifier where the gas is cooled to about 100° P., which is sufficient to condense the moisture, but not cool enough to con- dense the ammonia gas. Patent drip pipes drain back this condensed moisture to the generator so that only pure dry gas passes into the condenser, which, as will be seen by the diagram, is composed of a coil of pipe with another coil inside, through which water flows, commonly known as a double pipe condenser. The gas enters the top, flows through the annular space and is gradually condensed by the cold surface of the inside water coil. The liquid anhydrous ammonia which is clear and looks like water, flows down to the anhydrous THE ABSORPTION EEFHIGERATING MACHINE 79 receiver and when it appears in the gauge glass it is allowed to expand through an expansion valve into the brine cooler at about 15 lbs. pressure, where it evapo- rates and cools the brine which flows through the coils. This expansion valve is regulated so that only liquid will pass into the cooler. When opened too wide so that the liquid is exhausted, gas will pass into the cooler which has no appreciable cooling effect; in fact if the expansion valve is wide open the ammonia will be merely flowing around without producing any cold whatever. This liquid in the brine cooler as it is heated by the brine, turns into a gas which must be recovered and delivered again to the generator. For this purpose the outlet pipe is connected into the bottom of an ab- sorber which is kept full of weak ammonia which flows over from the generator and which, when cooled, is capable of reabsorbing the gas that has already been driven from it. This gas has such an affinity for liquor that it often makes a little crackling noise during the absorption which generates heat, and for this reason the absorber is full of tubes through which water flows to keep it cool. This strong solution is pumped back to the generator where it is redistilled. Since the cool liquor in the absorber has to be heated in the generator and the hot liquor in generator has to be cooled before it will reabsorb the gas in the absorber, an exchanger is used to save this heat; in fact, it heats the strong liquor the same as a feed water heater heats the boiler feed water before entering the boiler. The diagram shows also a double pipe weak liquor cooler where the weak liquor, after leaving the ex- changer, is further cooled with water before entering the absorber. The water for cooling purposes first flows through the condenser, condensing the ammonia, then through the absorber, and then through the weak liquor cooler 80 THE ABSORPTION HErKIGERATING MACHINE and rectifier. Generally, cooling water is obtained at about 60° or 70° F., and the temperature on leaving the machine is about 100° F. ATMOSPHERIC TYPE. The Atmospheric Type possesses the following ad- vantages : Where the atmospheric air is cooler than the outlet water, advantage can be taken of the air cooling efEect. If the water is muddy the coils can be easily brushed clean without stopping the machine. The condenser, absorber, weak liquor and rectifier coils can be placed on the roof, thus saving space in the engine room and requiring a cheaper building. Any dirt on them can be seen. They can be galvanized and kept painted so as to protect them from the corrosion of salt water. TUBULAR TYPE. The Tubular Type has the following advantages: All machinery can be placed in the engine room without having any splashing of water. The water can be pumped through the coils and delivered anywhere without repumping. There is less pipe surface to renew. With some kinds of water the pipes corrode and scale less. TYPE TO USE. AH types of the Carbondale system are designed so they will produce the same results, and that type should be selected which is most suitable for the conditions of operation. Generally the selection depends on the quality of the cooling water and whether the apparatus is to go in the engine room or on the roof. ADVANTAGES OF THE CARBONDALE ABSORPTION SYSTEM. (1) It takes very little steam, viz: 30 lbs. per hour per ton refrigerating effect. THE ABSORPTION REFRIGERATING MACHINE 81 (2) If exhaust siaam or waste heat is available it takes no live steam except that required to run the small ammonia pump. (3) It has no heavy moving parts and cannot be materially damaged by a careless engineer. (4) It has no oil to clog and insulate the pipes. (5) It takes a minimum amount of care and at- tention. (6) It does not require heavy foundations, can be placed on the top floor of a building and makes no noise or vibration. (7) It can easily and economically produce low temperatures. 8?, THE ABSORPTION KEFEIGERATING MACHINE CHAPTEK XIII. Columbus Absorption Machine — Description of Principal Parts — Generator — ^Ammonia Condenser — Cooler — ^Absorb- er — Ammonia Pump — Exchanger — Steam Condenser — Fore Cooler and Distilled Water Storage Tank. The principal parts of the Columbus improved ab- sorption ice machine are shown in Fig. 33. These parts are the generator, ammonia condenser, ammonia cooler, absorber, ammonia pump, exchanger, steam condenser and feed water heater, and the fore cooler and distilled water tank. The generator consists of a large semi-steel cylin- der, and may be divided into two parts, viz., the bot- tom half, or generator proper, and the top half, or rectifier. The lower half, or generator proper, con- tains a series of extra heavy wrought iron pipe coils, the inlets of which connect through the bottom of the generator by a manifold to the steam pipe from the steam boiler. The outlets of these coils are also connected by a manifold to a pipe which returns to the steam condenser. Around these coils is a twenty- six degree aqua ammonia, continuously supplied by the ammonia pump, and from which, as steam passes through the inside of the coils, the anhydrous gas is driven off. This gas then passes to the upper half, or rectifier, which contains a series of deflecting or baffle plates, and, by the arrangement of these deflect- ing or baffle plates the moisture in the anhydrous gas is taken out, and allows the gas to pass out of the top of the rectifier perfectly dry. From here this gas THE ABSORPTION REFRIGEHATIXG MACHIXE 83 is taken to the ammonia condensers. This boiling process having taken place, there is left, in the bottom of the boiler, a very weak charge of aqua ammonia (known as poor liquor) which is automatically driven off through the exchanger and cooling coils to the ab- GCNERATOR STEAH CDNDtNS£n FIG. 23. — SECTIONAL VIEW OF COLUMBUS ABSORPTION MACHINE. sorber. The steam on passing through the coils in this boiler is next taken into the steam condenser. AMMONIA CONDENSER. The ammonia condensers are of two types, viz., sub- merged and atmospheric. The submerged type con- sists merely of oblong extra heavy wrought iron pipe coils submerged in an oblong steel tank. The atmos- 84 THE ABSORPTION EEFBIGERATING MACHINE pheric is a series of oblong extra heavy wrought iron pipe coils placed on a deck or tower, and by means of sprinkler troughs over the top water is allowed to circulate over the outside of the coils. The anhydrous ammonia, on leaving the rectifier, passes through these condensing coils and the tem- perature is reduced below the boiling point of sat- urated ammonia at the pressure of the ammonia boil- er. This leaves the anhydrous ammonia in a liquid state, and it is then passed from these coils to the expansion valve, where it is expanded through the coils in the freezing tank, producing refrigeration. After passing through these freezing tank coils the rich gas is taken through the coil in the distilled water tank, and from there back to the absorber. COOLER. The construction of the cooler is similar to the condenser in both the atmospheric and submerged types. Poor liquor being drawn oil automatically from the generator through the exchanger, must be reduced in temperature before going to the absorber, as the colder the poor liquor, the more readily will it absorb the rich gas with which it comes in contact in the absorber. This reduction in temperature is accomplished by passing the poor liquor through the cooler coils, over which water is circulated, the same as over the ammonia condensers. From these coils the poor liquor is taken to the absorber and sprayed in at the top. ABSORBER. The absorber consists of a large semi-steel cylin- der containing extra heavy wrought iron pipe coils, very similar to the generator proper. The gas having been driven out of the aqua ammonia in the gen- erator, and having been condensed and expanded through the freezing tank coils, it is necessary to re- THE ABSORPTION REFKIQERATINO MACHINE 85 claim it, or mix it again with the poor liquor left in the bottom of the generator, so as to form the original aqua ammonia which is pumped into the generator. Thus the poor liquor is automatically passed through the exchanger and cooling coils, en- tering the absorber through a spray pipe near the top. The cold gas from the freezing tank, after pass- ing through the distilled water tank coil, enters the absorber and is sprayed upward through a spray pipe in the bottom of the absorber. In this manner the rich gas is re-absorbed by the poor liquor, and forms the original twenty-six degree aqua ammonia. All of this action takes place in the shell of the absorber, and being a chemical action, heat is generated. This heat is carried off by means of water being circulated through the pipe coils inside of the absorber and leaves a charge of rich ammonia at a temperature below that at which anhydrous is driven out; conse- quently it is in a complete liquid form, in which shape it is much easier to handle than in gaseous form. AMMONIA PUMP. The duplex fly-wheel ammonia pump used is the only moving part of the machine and this is so con- structed that either side is sufficiently large to take care of the machine independent of the other, there- by giving practically a duplicate plant. The am- monia stuffing boxes on this pump are of special de- sign, and any leakage that may take place around the ammonia stuffing box is returned through leakage chamber and bypass into the suction line. By this construction it is only required to pack against a liquid instead of gas, and to prevent loss of ammonia to pack only against the suction pressure, ranging from one to twelve pounds. The pump is used for circulating the ammonia, taking its suction from the bottom of the 86 THE ABSORPTION REFEIGEKATING MACHINE absorber, after the rich gas has been re-absorbed by the poor liquor, and discharging it through the exchanger shell into the top of the rectifier and from there into the ammonia boiler. EXCHANGER. The exchanger consists of a semi-steel cylinder con- taining an extra heavy wrought iron pipe coil, acting merely as an equalizer, or what may be plainer, a feed water heater for ammonia. The poor liquor coming from the ammonia boiler at a high temperature passes through the coil in this exchanger where it is partially cooled, and from here into the poor liquor cooler coils. The lower the tem- perature of this poor liquor the less work has to be done in the cooler coils and absorber. The rich am- monia taken from the absorber by the ammonia pump is discharged through the shell of the exchanger, and, of course, the higher the temperature of this am- monia on entering the generator the less work to be done there. Thus the forward ilow of rich ammonia is heated, and at the same time the return poor liquor cooled, thus economizing in both steam and water. STEALS! CONDENSER AND FEED WATER HEATER. The feed water heater consists of a semi-steel shell containing one or more circular coils. The boiler feed pump, taking its suction from the warm water which passes from the ammonia condenser coils, discharges it into the shell of this heater and from there direct to the steam boiler. The steam from the generator coils, after serving its purpose in boiling the aqua ammonia, passes through the shell of this heater and the same action takes place as in the exchanger. Thus the water going into the steam boiler is heated to a very high tem- perature, and at the same time the distilled water is THE ABSORPTION REFRIGERATING MACHINE 87 condensed and stored in the distilled water tank. This also is a saving in fuel as well as condensing water. FORE COOLER AND DISTILLED WATER STORAGE TANK. The fore-cooler and distilled water storage tank is a circular tank made of sheet steel and contains two coils. The distilled water after passing from the feed water heater or steam condenser is sprayed into the top of this tank and passes downward over the two coils. Through the top coil is circulated cold water, which carries off a great deal of the heat from the distilled water as it passes over. Through the bottom coil is circulated the return rich gas from the freezing tank, which, though it has performed its work in the freezing tank, is still at a very low temperature, and by passing it through the fore-cooler brings the tem- perature down to just a few degrees above the freezing point, thus leaving a minimum amount of work to be done in the freezing tank. In the top of this distilled water tank is placed a large opening, so that any foul gas coming over from the condenser, and which condenses at a lower tem- perature than the steam, is allowed to pass out into the atmosphere. This tank is also fitted with a goose- neck water sealed overflow pipe, so that, if for any reason, the ice cans in the freezing tank are not filled, surplus distilled water can be carried ofE and either allowed to go to waste or stored in an auxiliary tank. This prevents any undue pressure in the distilled '.vater tank, or the backing of the distilled water into the steam condensers. As a summary, the operation of this machine may be defined as follows: Steam admitted to coils in the ammonia boiler drives off the gas, which ascends through the rectifier where it is dehydrated. Trom there this gas passes to the condenser, is liquefied, and then expanded into 88 THE ABSOEPTION REFRIGERATING MACHINE the freezing tank coils. After passing through these coils it goes through a coil in the distilled water tank, and thence to the absorber where it is re-absorbed by the poor liquor returning from the ammonia boiler, which poor liquor has first been cooled by passing through poor liquor cooler and exchanger coil. This enriched liquor is then pumped through the exchanger shell to the ammonia boiler, and commences the same continuous cycle of operation again. THE AIISORPTIOX REFRIOEHATINQ MACHINE 89 CHAPTER XIV. Description of Polar Absorption Machine — Various Parts of Machine — (Jeneral Construction — Operation — Kfhciency^ Installation. The Polar Refrigerating Machine, of the absorption type, consists of a still for evaporating dry ammonia gas from a solution of aqua ammonia; a condenser for liquefying the gas; a brine cooler, expansion coils or other apparatus in which the liquid ammonia expands again into a gas, thus producing the cold; an absorber in which the gas is absorbed by weak aqua ammonia from the still, which is thereby enriched, and an am- monia pump which returns the rich liquor from the absorber to the still, in order that the gas may be re- evaporated, thus making a continuous process. The generator, analyzer, rectifier and heater or ex- changer form the still in Fig. 24, which shows a dia- gram of the machine. The charge of aqua ammonia in the generator is heated by steam passed through coils A. The latent heat of the steam is the principal factor used for this purpose, the steam being condensed in the coils from which it may be trapped and returned to the boiler at practically the temperature correspond- ing to the pressure under which it is condensed. The heat derived from the steam drives the ammonia gas out of the solution under pressure and it passes upward through the analyzer where any water held in sus- pension is removed by a series of trays which act as baffle plates. The gas then passes to the rectifier through pipe B where any moisture is condensed, trap- 90 THE ABSORPTION REFRIGERATING MACHINE THE ABSORPTION' REFRIGERATING MACHINE 91 ped off and returned to the generator through pipe 0. In some cases, owing to local conditions, such as the quality of the water, location of the rectifier, etc., at- mospheric and double-pipe rectifiers are installed, shown in Figs. 25 and 26, instead of the submerged type shown in Fig. 24. Their operation is similar. The anhydrous gas thus formed then passes to the condenser through pipe D, where it is cooled by contact with the water cooling coils, E, and thus liquefied or condensed. Condensers of the atmospheric and double- pipe type, shown in Figs. 27 and 28, are also installed, but they are not as efficient as the shell and coil type of condenser shown. Local water conditions frequently make one of the open types preferable, but it is neces- sary to allow considerably more floor space for them. The liquid anhydrous ammonia falls to the bottom of the condenser which serves as a reservoir, or, in some cases, where a condenser of several sections is used, a separate receiver is installed and all sections are drained into it. The ammonia liquid is then conducted by pip- ing to a brine cooler, or some form of expansion coil located in a brine tank or in rooms or boxes to be re- frigerated, being fed into the cooler or coils through an expansion or regulating valve F, which allows a very fine adjustment of feed. After passing this regulating valve the liquid may then absorb the heat from the brine, or room, or articles to be refrigerated, and in taking up this heat passes or is changed from the liquid to the gaseous form again. The ammonia, again in the form of anhydrous gas, passes to the absorber, shown in Figs. 24 and 29, by pipe G, where it comes into intimate contact with the weak ammonia liquor from the bottom of the gene- rator. The higher pressure in the generator causes the weak aqua, left after the gas is evaporated, to flow through the honter or exchanger to the absorber by THE ABSORPTION REFRIGERATING MACHINE THE ABSORPTION KEFKIGERATINO MACHINE 93 8^ i > K o a: 94 THE ABSORPTION REFRIGERATING MACHINE pipes H and I. Upon entering the absorber the weak aqua passes through a regulating valve and it is sprayed out over the cooling coils K, through which the cooling water from the condenser is circulated, and which re- moves the heat generated in the absorber, owing to the absorption of the gas by the aqua ammonia. In some eases the weak aqua on its way to the heater from the absorber is passed through a weak liquor cooler. Hori- zontal tubular absorbers are also built, for use with salt or scale-forming water, where frequent cleaning is necessary. These are held to be more efficient than the vertical tubular absorbers, owing to the counter current of ammonia and cooling water, but require more floor space. The rich or strong liquor thus formed in the ab- sorber by the union of the returning gas and weak liquor is then removed by a small, slow-moving am- monia pump, through the pipe J, which returns the strong aqua ammonia through the heater to the gen- erator. The heater is simply an economizer, and serves as an exchanger of heat between the strong and the weak aqua, cooling the weak liquor before it goes to the absorber and heating the strong liquor on its return to the generator. From the heater the strong liquor passes to the analyzer through the pipe L, and thus ilows down through the analyzer trays, being further heated before reaching the generator. The brine cooler, as its name indicates, is a vessel in which brine is cooled by the ammonia for the pur- pose of distributing the refrigeration produced by the machine. The shell and coil type, illustrated in Figs. 34 and 30, is the most efficient type of brine cooler made. It consists of a shell with continuously wound coils running through it, the whole vessel being in- cased in heavy insulation. The brine is pumped through the coils where it is cooled and from there it THE ABSORPTION REFBIGERATIXG MACJIIXE 96 THE ABSORPTION EEFEIGERATING MACHINE passes to the rooms or apparatus which are to be re- frigerated, returning to a brine storage tank, from whence it is again taken by the pump and passed through the cooler, etc., in a continuous operation. In conjunction with the stills and absorbers these coolers, in a number of cases, are commercially cooling brine to thirty-five degrees below zero. CONSTRUCTION OF THE MACHINE. The closed vessels of the machine are all made with either heavy cast-iron or steel shells and heads. All continuously wound coils are welded throughout and made of wrought-iron, lap-welded, extra heavy pipe projecting through stuffing boxes in the heads and term- inating in headers or junction boxes outside of the shells. The generators and submerged rectifiers have oval coils. The coils on condensers and absorbers are provided with valves and tees so arranged that any one coil may be cut out and opened for cleaning purposes, while the vessel is in operation. All openings in shells for connections are either flanged or tapped, and when tapped, are re-enforced with stuffing boxes and glands, and all valves and fittings are extra heavy to guard against leakage. Each pipe line between vessels is protected by one or more valves easily accessible and care is always taken in erecting the piping to see that it is properly supported. Draining connections are made to the absorber to facilitate emptying the various vessels of ammonia should the occasion require. All vessels are provided with automatically closing liquid level gauges and pressure gauges mounted on a deco- rative cast-iron gauge board. The ammonia pumps are controlled by automatic governi)rs in order to main- tain a constant aqua ammonia level in the absorber. The coils in the generators are constructed so as to allow of free drainage of the steam condensed in them. In condensers, absorbers and coolers of the shell and THE ABSORPTION BEFEIGERATING MACHINE 88 THE ABSORPTION EEFHIGEKATING MACHINE coil type the double wound coils are frequently used, which, in comparison with the single wound coils, will permit the same amount of water or brine to be cir- culated through them with about half the friction pres- sure. Absorbers and coolers with double coil winding are illustrated in Figs. 39 and 30, respectively. This type of double wound coil is always used for the con- denser and absorber where warm condensing water is encountered. On exhaust steam machines the generator coils are also frequently of the double wound type. OPERATION' OF THE MACHINE. The skill required to operate the Polar machine is such as is needed to run a boiler. The engineer has under his control the weak liquor valve and the usual expansion valve or valves depending upon the apparatus to which the high pressure side of the machine is con- nected. These are the only valves needing adjustment while the machine is in operation. The valves for the steam to the generator and the ammonia pump are controlled by automatic regulators, that for the am- monia pump adjusting itself for any given positions of the expansion and weak aqua valves. The machine has but one moving part, the ammonia pump, its mo- tion being extremely slow ; and because of this lack of moving parts the machine can be operated continuously twenty-four hours a day for an entire season without undue wear and tear. Different degrees of temperature may be maintained by very slight changes in the ex- pansion and weak liquor valves. EFFICIENCY. The machine receives its power directly from the latent heat of steam without the wasteful losses ex- perienced in a steam engine. The steam condensed in the generator coils may be returned to the boiler at a temperature corresponding to its pressure and always much above that of the average feed water. All hot or THE ABSOUPTION nEFRIGERATING MACHINE 99 ;old parts of the machine arc thoroughly insulated to avoid any loss to or from the atmosphere or surround- ings. This type of machine permits using the exhaust FIG. 29. — ISBELL-PORTER ABSORBER, PUMP GOVERNOR ATTACHED. steam from the ammonia, brine, water, or other auxil- iary pumps in the generator coils. With this use of exhaust steam the machine surpasses in efficiency the 100 THE ABSOKPTION REFEIGEEATING MACHINE most approved form of steam engine that may be used in driving a compressor and also gives an extremely low coal consumption for a plant so equipped. In cold storage work one still and condenser may be used to operate two different sets of absorbers and coolers operating on high and low temperature brine respect- ively, which is the most efficient manner of carrying high and low temperature rooms in a cold storage warehouse. The machine operates as economically on zero temperatures as at twenty degrees above zero. Where low temperatures are essential, low back pressure may be maintained and a large volume of low pressure gas absorbed by slightly increasing the weak liquor feed and the speed of the ammonia pump. INSTALLATION. The absorption machine is absolutely noiseless in operation and free from vibration, owing to the absence of heavy moving parts. This also obviates the neces- sity of building large and heavy foundations, as the machine may be placed upon any substantial floor. For these reasons, the machine is particularly adapted for use in large steel buildings, hospitals, apartment houses, as well as in the regular line of cold storage ware- houses, fish freezers and ice making plants. The differ- ent parts of the machine are symmetrically arranged, compact in appearance and, when necessary, may be placed in an extremely small area, although it is of course advisable to have sufficient room around the vessels so that they may be properly and conveniently cared for. A supply of condensing water is of course essential to the operation of any refrigerating machine. The amount of water must be determined by its temperature and quality. The surfaces of the Polar machine are designed and arranged so that the water from the con- denser will be sufficient for use in the absorber through THE ABSORPTION REFRIGERATING MACHINE 101 FIG. 30. — ISBELL-PORTER BRINE COOLER, SHELL TYPE. 103 THE ABSORPTION EEFRIGEKATING MACHINE which it is passed on leaving the condenser, and the water from the machine may at all times be used in the building, for boiler feed and sanitary purposes, cooking, washing, etc. One of the most important uses of the machine is in connection with plate ice plants. Its high efficiency at low temperatures in connection with a brine cooler makes it possible to freeze and harvest plate ice in forty-eight hours, or less, with the same, or better, econ- omy than may be obtained when the freezing is done at temperatures considerably above zero. Til 12 ABSORPTION REFRIGERATING MACHINE 103 CHAPTER XV. Description of Vogt Absorption Machine — Construction of Generator, Rectifier, Separator, Condenser, Weak Liquor Cooler, Exchanger, Aqua Ammonia Pump, Absorber and Brine Cooler — Operation of Machine. The latest type of Vogt absorption machine is il- lustrated in Fig. 31. It embodies several new features and improvements in construction, yet adheres strictly to the well-known principle of the Vogt machine, that of not having any spiral coils or bent pipes submerged in ammonia. The generator consists 'of two or more horizontal cylinders mounted one above the other. These cylin- ders contain the steam heating coils which are made of extra heavy straight pipe connected with steel return bends. On top of uppermost horizontal cylinder is placed the analyzer, which consists of a cylinder con- taining a series of perforated trays and baffle plates. The rectifier or dehydrator is of the double pipe type. The gas from generator enters at the top and travels downward through the annular space between the two pipes and out at the bottom. The strong liquid is used as a rectifying medium and enters the coils at the bottom and passes through the inner pipe in an upward direction and out at the top. A separator con- taining a series of baffle plates is used with rectifier in order that the watery vapors that have condensed in rectifier may be separated and trapped back to gen- erator. The condenser is of the double pipe type. The gas from separator enters at the top and travels downward 104 THE ABSORPTION KEFEIGBKATING MACHINE through the annular space between the two pipes and out at the bottom. The cooling water enters at the bot- tom and passes through the inner pipe in an upward direction and out at the top. The weak liquor cooler is of the double pipe type, and built exactly like the condenser. The weak liquid enters at the top and travels through the outside pipe like the gas in the condenser. Both the condenser and weak liquid cooler coils are connected up with flushing headers so that each coil may be shut o£E, the flow of water reversed and mud blown out without interfering with the operation of any other coil. The water bends can be easily disconnected without disturbing the am- monia joints, leaving the inner pipe open at each end for cleaning and inspection. The exchanger is of the double pipe type. The weak liquid from the generator enters at the top and travels downward through the outside pipe and out at the bottom. The strong liquid from rectifler enters at the bottom and passes upward through the inner pipe and out at the top. All the double pipe constructions of the Vogt machine are made with stuffing boxes on one end of each pipe only; the other end is held firmly threaded in a flange having a tongue and groove joint and bolted to header. The aqua ammonia pump is of the double-acting, fly-wheel type, of heavy design and usually operates at from 18 to 35 revolutions per minute. It is regulated by a Mason oil governor so as to maintain a constant speed under varying steam pressures. The speed of pump can be instantly changed by simply inserting a key and turning to the right for a lower, and to the left for a higher speed. The absorber, shown in Fig. 31, is the horizontal tubular type. The shell, piade of flange steel, is riv- eted or welded to heavy steel heads at each end, through which the tubes are inserted and expanded. The tubes THE ABSOBPTION REFniGEHATING MACHINE 106 106 THE ABSORPTION REFRIGERATING MACHINE are made of extra heavy charcoal iron and arranged so that with the baffle heads bolted on each end, the cooling water will pass eight or more times the entire length of the absorber, thus increasing the circulation of the cooling water, and the efficiency of the cooling surface. The gas enters the bottom of the absorber through perforated pipes. The weak liquid enters the top of the absorber through a number of spray nozzles, and any ammonia gas that has passed through the liquid in the shell without being absorbed by same will be in- stantly absorbed by the weak liquid spray at the top. An automatic regulator is used in connection with the absorber to automatically control the flow of weak liquid to same. The brine cooler, shown in Fig. 31, is of the hori- zontal tubular type. It is almost identical in construc- tion with the horizontal tubular absorber Just described. The liquid ammonia is contained in the shell, from one- half to three-quarter full; the brine is circulated through the tubes eight or more times the entire length of the cooler. When located in a room exposed to at- mospheric temperatures the cooler is usually insulated with sheet cork and lagged with hard wood. While the type of machine illustrated is their latest and preferred construction, the manufacturers of the Vogt machine, when required, use their vertical tubular absorber, and when the cooling water makes it necessary, will use at- mospheric type absorber, condenser and weak liquid cooler. A liquid anhydrous ammonia receiver is usually connected in on liquid line from bottom of ammonia condensei to brine cooler ; this is not shown in the illus- tration, because with the shell type brine cooler, the same can be used as a receiver and a separate receiver omitted if desired. OPERATION OP VOGT MACHINE. The operation of the Vogt type absorption machine may be summarized as follows: THE ABSORPTION UEFBIOERATING MACHINE 107 The strong charge of aqua ammonia is drawn from the absorber and pumped to the bottom of the rectifier and travels upward through the inner pipes, and out at top, and on to the bottom of exchanger; the liquid travels up\<'ard through the inner pipes and out at top and on to analyzer, where the liquid falls in a spray from one pan to another until it reaches the top cylin- der of generator; it then flows the entire length of top pipe, overflows to the second pipe, travels the entire length of second pipe and overflows into bottom pipe. After having traveled the entire length of the three horizontal cylinders over the steam heating coils, the remaining weak liquid is taken off at the end of bot- tom cylinder farthest away from the strong liquid in- let, and conducted to the top of the exchanger ; here the weak liquid travels dowiiwnid through the outside pipe and out from bottom to top of the weak liquid cooler, and downward through the outside pipe of same, and out at the bottom, and on to the regulating valve on the absorber. From the regulator the weak liquor is admitted to the absorber in quantities proportional to the liquid pumped out of the bottom of absorber. The gas generated from the strong aqua by the steam coils, passes out at the top of each horizontal cylinder and up to analyzer where the gas passes through the strong liquid spray, and on through a series of baffle plates to remove moisture from same. From the analyzer the gas is conducted to top of the rectifier and travels downward through the outside pipe and out at bottom to the separator; here the moisture that may yet remain in the gas is separated and drained from bottom of separator and admitted to the top cylin- der of the generator. The gas from the separator passes to the condenser at the top and the liquefied ammonia is taken out at the bottom and conducted either to a receiver or direct to the brine cooler. The gas generated by the evaporation of the liquid ammonia in the brine 108 THE ABSORPTION REFRIGERATING MACHINE cooler is conducted from top of brine cooler to bottom of the absorber. Here the weak aqua rapidly re-absorbs the gas, forming again a strong solution of aqua am- monia, and the double cycle of circulation is thus com- pleted. THE ABSOHPTION KEFHIGEKATIXG MACHIXE 109 CHAPTER XVI. Description of the York Absorption Machines — Shell and Coil Generators — Multitubular Generator — Analyzer — Dehy- drator — Condenser — Absorber — Exchanger — Weak Aqua Cooler — Aqua Pump — Brine Coolers — The Kcveral Types of Each Apparatus Outlined. Two types of generators are built, one known as the horizontal shell type with a vertical analyzer, and the other known as the multi-tubular type, having a hori- zontal analyzer. The shell and coil type generator is made of flanged steel, having a tensile strength of from 55,000 to 60,000 pounds per square inch. The flanges are made of steel and the heads of air furnace iron. All seams are welded, no rivets whatever being used. The ends of the shell are annealed and flanged over the steel rings which are shrunk on the shell. The flanged portions of the shell are machined so as to form the male part of a male and female joint with the head. After comple- tion the generator is subjected to a hydraulic test of 500 pounds per square inch. The shell contains a ser- ies of continuously welded trombone style coils, made of extra heavy lap-welded wrought-iron pipe. When desired, these coils are also made up with special return bends. The vertical analyzer used on this generator has a welded shell, air furnace iron heads, and steel flanges, constructed same as generator shell, and is connected to the generator by means of a large steel nozzle welded to generator shell, at one end, as shown in Fig. 32, 110 THE ABSOKPTION KEFEIGERATING MACHINE and contains a series of improved perforated cast iroE trays. The multi-tubular generator consists of one or more shells, placed one on top of the other, and supported by cast iron stands. The shells are welded and the heads are of air furnace iron, with steel flanges, same as generator shell described heretofore. The heating surface is of double tube construction. The tubes being made of extra heavy lap welded pipe, the inner or Sas Oui*l Strang Avua - Intti 'Drain HiatAcjuaOuUt FIG. 32. — YOEK SHELL AND COIL GENERATOR AND VERTICAL ANALYZER. steam inlet tubes being connected to a steam chamber, and extending to the rear of the outer tube which is closed at rear end, and which is connected to a drain chamber at the front end. Bach shell is provided with a gas outlet; strong aqua inlet; weak aqua outlet; pump-out; gauge and purge connections. When more than one shell is used, they are usually operated in series, but they are connected in such a manner that they can be operated in multiple. THE ABSOEPTION EEFKIGEUATIXG SIACHINE 111 The horizontal analyzer consists of a welded steel shell, having long cast iron trays, placed in a horizontal position. A gas inlet and outlet connection is pro- vided, also a strong aqua inlet and outlet, and a drip connection from dehydrator, as shown in Fig. 33. Two types of dehydrators are built, the submerged type and the atmospheric type. The submerged de- hydrator consists of a rectangular tank, having one or more extra heavy continuously welded trombone style coils, each coil made to drain to bottom pipe, which is Outtt MWa.4fua.OuM FIG. 33. — HORIZONTAL ANALYZER AND MULTI-TUBULAR GENERATOR. connected to a high pressure separator, which separates the weak liquor condensed in the dehydrator and returns it to the analyzer; the gas passing through the sep- arator to the ammonia condenser. The atmospheric type dehydrator consists of one or more coils, return bend type. A drain connection is made from each return bend to the separator, and each coil is provided with a cooling water sprinkling device. The ammonia condenser is made in three types, the atmospheric, double pipe counter current, and the shell and coil type. The atmospheric type consists of 113 THE ABSOKPTION EEFEIGBHATING MACHINE Tllli ABSORPTION KEFRIGERATING MACHINE 113 coils made up with return bends. They are provided with slotted pipe or galvanized trough sprinkling device, and are made with either a vertical or horizontal preliminary coil. The illustration, Fig. 34, shows a condenser having a horizontal preliminary. The double pipe counter current ammonia con- denser consists of one or more coils having a pipe within FIG. 35. — YORK DOUBLE-PIPE AMMONIA CONDENSER. a pipe. The cooling water passes through the inner pipe and the ammonia through the outer pipe. In the condenser shown in Fig. 35, numbers one and two in-l dicate the gas inlet and liquid outlet, while four and five indicate the water connections, and three represents the purge out. The shell and coil ammonia condenser is made with a welded flange steel shell with air furnace iron heads 114 THE ABSOEPTION EEFEIGEEATING MACHINE and steel flanges, and contains a number of extra heavy contimionsly welded coils, as shown in Fig. 40. The joints on shell are made same as the generator and analyzer, and both shell and coils are tested with a hydraulic pressure of 500 pounds per square inch. TYPES OF APPAEATUS. The absorber is made in three types, the horizontal tubular, vertical shell and coil, and atmospheric type. The horizontal tubular type consists of a welded shell with cast iron water heads and heavy flanged steel tube heads, into which are expanded the tubes. The water chambers at each end are divided into a number of parts, causing the water to pass repeatedly ays out ,S.JlOvcr/law WaimvlnUi WaUeOuUi -(SaalnUi ftufga Jn. FIG. 36. — YORK HORIZONTAL TUBE ABSORBER. back and forth through the tubes and various water chambers, the water entering the top set of tubes and finally leaving the bottom set. The gas and weak aqua enters the shell at the bottom through perforated distributing pipes and the strong aqua overflowing at the top as shown in Fig. 36. The vertical shell and coil absorber consists of a welded shell with steel flanges and air furnace iron heads, made in the same way as the generator and subjected to the same hydraulic test. It contains a series of continuously welded extra heavy pipe coils, and is provided with a perforated gas and weak aqua dis- tributing spreader in the bottom, and a strong aqua THE ABSORPTION RKl-niGERATING MACHINE 115 1h 116 THE ABSOEPTIOII EBFEIGEEATING MACHINE THE AHSOliPTIoN REFRIGERATING MACHINE 117 118 THE ABSOEPTION REFEIGEKATING MACHINE overflow at the top. The cooling water enters the coils at top and leaves at the bottom. The atmospheric absorber shown in Fig. 37, consists of one or more coils, made up with return bends. The weak aqua enters the bottom pipe which has a per- forated gas distributing pipe, the strong aqua over- flowing from the top pipe. Each coil is provided with either a slotted pipe sprinkling device or a galvanized sprinkling trough. Each absorber, regardless of type, is furnished with a strong aqua tank or receiver, from which the aqua ammonia pump takes its suction; the strong aqua from the absorber overflowing into the tank. This is a cylindrical tank supported on cast iron stands, and is made of flanged steel shell, with welded longitudinal seams; the heads are of flanged steel welded to shell. It is provided with glass liquid level gauges with auto- matic cocks. The exchanger is made in two types, the double pipe type, and the vertical shell and coil type. The double pipe type consists of one or more coils, having a pipe within a pipe, assembled with gland flttings; the strong aqua passing through the inner pipes, and the weak aqua between the inner and outer pipes, as indicated in Pig. 38. The vertical shell and coil exchanger is made sim- ilar to the shell and coil condenser (Fig. 40). It has a welded flange steel shell with heavy air furnace iron heads and steel flanges, and contains a number of con- tinuously welded coils, made of extra heavy lap welded pipe. All joints are made as explained under head of shell and coil generator, and are subjected to the same hydraulic test. The strong aqua enters the bot- tom of shell and overflow's at top, while the weak aqua enters the coils at top of shell and leaves same at the bottom. THE ABSORl'TION HEFRIOERATINQ MACHINE 119 The weak aqua cooler is made in two types, the double pipe, and the atmospheric type. The double pipe type is constructed similar to the double pipe ammonia condenser, having a pipe within a pipe, with gland fittings; the weak aqua entering the outer top pipe and leaving at the bottom, while FIG. 40. — SHELL AND COIL EXCHANGER, CONDENSER, BRINE COOLER AND ABSORBER. the cooling water enters the inner bottom pipe and leaves the top one. The atmospheric type weak aqua cooler consists of one or more straight coils, made up with return bends, or continuously welded, with slotted cooling water sprinkling device or galvanized trough on top; the 130 THE ABSORPTION EEFEIGERATING MACHINE weak aqua entering the bottom pipe of coil and leaving at the top. The aqua ammonia pump is a double acting type, and is capable of handling any strength of aqua without becoming gas bound. Each pump is provided with a suitable cast iron base which acts as a drip pan, and is furnished with a suitable speed regulator which auto- matically regulates the speed of the pump. The brine coolers are made in three types, the double pipe counter current; vertical shell and coil, and horizontal shell and tube. The double pipe counter current type consists of one or more coils, having a pipe within a pipe with gland fittings. It is shown in Fig. 39. Numbers one and two indicate the ammonia outlet and inlet, while four and five show the brine inlet and outlet, and num- ber three is the purging out connection. The vertical shell and coil brine cooler is made practically the same as the shell and coil ammonia condenser (Fig. 40), having a welded flange steel shell, air furnace iron heads and steel flanges, and is sup- ported by means of cast iron legs attached to the lugs which are provided on the bottom head. It contains a number of coils continuously welded and made of extra heavy lap welded pipe. The liquid anhydrous ammonia is injected into the bottom and the gas leaves the top of shell. The brine is pumped into the bottom of coils and leaves the top. The horizontal shell and tube brine cooler is made very similar to the shell and tube absorber shown in Fig. 36. It has a welded flange steel shell and tube heads, and east iron brine heads. The shell is filled with extra heavy tubes expanded into tube head. The brine chambers at each end are divided into a number of compartments; the brine entering the bottom of brine head, passing through the tubes and compart- ments at a high velocity, and leaving at the top. The shell is supported on heavy cast iron stands. THE ABSORl'TION RKKRIGEKATING MACHINE 121 CHAPTER XVII. Voorhees' Multiple Effect Receiver — Prevention of Evapora- tion at the Expansion Valve — Tables Showing Gains Made. Referring to "Refrigerating Machines, Compression, Absorption," on page 15, is given a copyrighted table which is here reproduced as follows: Condenser pressure 140 lbs. 170 lbs. 200 lbs. Condenser temperature 80° 90° 100* Refrigerator pressure. lbs 431 lb. .441 lb. ,451 Ibi Refrigerator temperature, 29° 19.0% 20.8% 22.5% Refrigerator pressure, 15 lbs 420 1b. .430 lb. .440 1b. Refrigerator temperature, 0° 14.4% 16.2% 18.0% Refrigerator pressure, 30 lbs 415 1b. .425 1b. .434 1b. Refrigerator temperature. 17° 11,0% 13.4% 15.2% Copyright In United States and Great Britain. In the above table the pounds of ammonia per min- ute per ton of refrigeration and the per cent of this amount of ammonia that is evaporated at the expan- sion valve are given for 0, 15 and 30 pounds gauge back pressure, and for 140, 170 and 200 pounds con- denser pressure, together with ammonia temperatures due to these back and condenser pressures. An inspection of this table will show that from 11.69{> to 22.5% of the liquid ammonia is evaporated at the expansion valve in cooling the liquid ammonia from its temperature due to the condensing pressure, to that due to its back pressure. The ammonia so evaporated at the expansion valve does practically no actual refrigeration in the refrig- erator and requires just as much power to get it back into the condenser as does an equal amount of vapor formed from ammonia liquid evaporated in the refrigerator. 132 THE ABSORPTION EEFEIGEEATING MACHINE If this evaporation at the expansion valve could be prevented, in whole or in part, the capacity of the re- frigerating machine would be increased and the power to operate it would be reduced. For example, at 200 pounds condenser and pounds back pressure the per cent of ammonia evaporated at the expansion valve is 22.5%. If this evaporation could be entirely prevented the capacity of the machine would be increased 29%: 100 77.5 The Voorhees Multiple Effect Eeceiver (patented), hereafter called M. E. E., is designed to prevent nearly all of such evaporation at the expansion valve. The device is simplicity itself, but in order to use it the refrigerating system must be operated at two different back pressures. This may be done by means of a Multiple Effect Compressor, hereafter called M. E. C. (for description, see January, 1907, and February, 1911, Ice and Refrig- eration), or through a multiple effect absorption sys- tem, or by using two different back pressures, one on each side of the piston of a double-acting compressor, or by two compressors or two absorbers. Briefly, the M. E. E. takes out most of the vapor, at a high pressure expansion valve, that would other- wise be formed at the low pressure expansion valve and the resultant liquid ammonia so cooled and freed from vapor is again expanded through the low pressure ex- pansion valve. In the figure, which is diagrammatic and which has the relative size of the M. E. E. greatly exaggerated for clearness, the ordinary cycle of operations (if the M. E. E. and high pressure refrigerator were not used and if the M. E. C. were operated as a common com- pressor at one back pressure) is as follows: THE ABSORPTION REFRIGERATING MACHINE 123 Assume 200 pounds condenser and 15 pounds back pressure; under these conditions the liquid ammonia flows from the condenser through the dotted pipe to expansion valve B, where its pressure is reduced from 200 to 15 pounds and its temperature from 100° F. to 0° F., thereby evaporating 18% of its weight in so cooling itself. Now, if in place of having the liquid ammonia from the condenser go directly to expansion valve B, it passes the float-governed expansion valve A, and into the M. E. E., it is evident that the ammonia C I CONDENaCR receiver; 5a S» Sr: COOLS AMMONl/\ Cmqrt PRESSUR E . REPRICE RAT0R3 1,5 V ^^ - FORECOOLE.R ) Cools v//\ter pnzh •iultiple EFFECT :oMPRes)of> 15 SINI^LE ACTIN(^ TYPE c LO\A) PRESSURE) C REFRIGERATOR OR ) (FREEZINCi-TAw ic FKItZta WATER^ liquid will cool itself to the temperature due to the pressure in the* M. E. E. and that the vapor so formed will flow out of the top of the SI. E. E. to the high pressure suction inlet of the M. E. C and the result- ant cold liquid ammonia free from vapor will flow from the M. E. E. past expansion valve B, whereat its pres- sure is finally reduced to 15 pounds, and a small quan- tity of* vapor is so formed in further cooling the liquid to 0° F. 134 THE ABSORPTION REFEIGEEATING MACHINE If the pressure in the M. B. E. were the same as that in the low pressure refrigerator all the vapor that would ordinarily be formed at expansion valve B would be formed in the M. E. E., and the liquid ammonia would be cooled to the refrigerator temperature, which, in this ease, would be the exact duplicate of the accumu- lator of a flooded system. This, however, is not the ease, for the pressure in the M. E. E. is a little higher than that in the low pressure refrigerator (and there- fore the liquid ammonia is a little warmer than the low pressure refrigerator), dependent upon the require- ments of the refrigerating system. In its simplest application the M. E. E. has a pressure just enough higher than that of the low pres- sure refrigerator to take care of the maximum possible quantity of vapor that would otherwise be formed at the low pressure expansion valve. If two back pressures are to be used they should be used to their maximum advantage. In all applications of refrigeration the refrigeration is either done at two different back pressures or could to advantage be so done; particularly when it is remembered that the capacity and economy of a compressor increases as the back pressure increases. The two back pressures are determined by the nature of the refrigeration to be done. When any part of the refrigeration of a system could be done at a higher back pressure the whole plant is operated at a daily loss of capacity and increased cost for coal if it is not so done. For high temperature work a high back pressure is used and for low temperature work a low back pressure is used. So for ice making use high back pressure to cool the water to say 34° F. and low back pressure to freeze the water into ice. In cold storage or packing houses use high back pressure for the cooling rooms and low back pressure for the freezing rooms. In breweries use high back pressure for the Baudelot THE ABSORPTION REFRIGERATING MACHINE 125 coolers and low back pressure for the cellars. In air cooling for blast furnaces use high back pressure to partly cool the air and low back pressure to finish the cooling, thus cooling the air in two stages, etc. Looking again at the figure, let us consider an ice making plant with 90° condensing water and 15 pounds back pressure. This will give us 200 pounds condensing pressure and 100° liquid ammonia from the condenser and 100° water from the flat cooler. To cool one pound of this 100° water in a forecooler requires 66 B. T. TJ. (100—34X1=66). To cool the 34° water to 33°, freeze it into ice and cool the ice to the brine tempera- ture requires 154 B. T. U., or, in all, 220 B. T. U., and to this must be added the various losses due to exposure, meltage from the cans, etc. — in all about 10% more. But such losses apply to the forecooler nearly as much as to the rest of the system, so that in cooling the water from 100° to 34° we used 30% of the refrigera- tion required for the whole process (66^220^.30). Now all of this 30% could be done at a higher back pressure than 15 pounds, and if it were so done it is evident that the ice making capacity of the 15-pound back pressure compressor would be increased thereby by 43% (.70+.30-f-.70=1.43). The high back pressure can be anything desired ac- cording to the quality of refrigeration to be done by it, so long as the temperature due it is not too high. In this case it could be anything from 15 pounds to 50 pounds, according to the refrigeration to be done in the forecooler. With the use of a M. E. C. and a M. E. E. this high back pressure automatically regulates itself with- out any attention whatsoever on the part of the engineer to the speed of the compressor or the high pressure ex- pansion valve. The automatic float expansion valve A in the II. E. E. takes care of this at all times and under all conditions. 136 THE ABSOEPTION EEFEIGERATING MACHINE In the figure we see that the high pressure refrig- erator which is now used as a forecooler to cool the water from 100° to 34° is connected to the M. E. E. just as a flooded system refrigerator would be connected to an accumulator, so the liquid from the M. E. E. circulates from the M. E. E. through the high pressure refrigerator (forecooler), the resultant vapor and some liquid returns to the M. E. E. and the vapor rises and joins that formed at expansion valve A, and passes out to the high pressure suction inlet of the M. E. C. Here we see the M. E. E. has the compound func- tions, 1st, of cooling all the liquid ammonia for both high and low pressure refrigerators ; 3d, of acting as an accumulator for the high pressure refrigerator (fore- cooler) ; 3d, of regulating the quantity of ammonia used in the high pressure refrigerator (forecooler). With such a system, which can easily be applied to any exist- ing plant, the following advantages result : More ice for less power per ton of ice; the same quantity of ice for less power per ton of ice for a slower speed of com- pressor. The ice making case above cited is less severe than most of the Southern ice making conditions. With a Multiple Effect Eeceiver the increase in capacity of a common compressor made multiple effect would (if the volumetric efficiency remained constant) be proportionate to the absolute back pressures used, plus the gain of the M. E. E. When using a compressor M. E. C. the volumetric efficiency is greatly increased over that of a common compressor because the high back pressure gas comes into a comparatively cool cylinder just after suction of the low back pressure vapor — in place of coming in con- tact with a hot cylinder just after discharging a cylin- der of hot gas into the condenser (see p. 20. Eef. Maeh. Comp. Abs.). All common compressors are usually built with large enough engines to operate at high back pressure THE ACSORPTIOX REFRIGERATING MACHINE 127 60 such engines will be powerful enough, if such a compressor is made M. E. C, and even if not, a slightly higher boiler pressure would make them so. Cut out a short piece of your suction pipe, put in a M. E. C. device, put a collar on the piston rod and a link motion to be actuated by collar to move valve in M. E. C. device, and your compressor is made M. E. C. When you remember the cost saved of foundations, extra engine room space, attendance, oil, waste, repair of same, and at the same time the cost to change the simple compressor engine to a compound one you will see where the money inducement lies. A new compressor M. E. C. would cost practically the same as an old style compressor. The following table will give a guide as to what can be done as to extra capacity and saving to power : ComparlBon of Ice Making Capacities and Horse Power of Compres- sion Machines for 00° Condensing Water, 15 lb. Back Pressure and 200 lb. Condensing Pressure, with Present Compressor Oper- ated at a Constant Speed Under These Conditions, and with Some AddUions to or Modincatlons of Ice Making Plants. Increased Decreased ice-making h. p. per capacity. ton ice. Present compressor and present apparatus. . 0% 0% Present compressor with a M. E. R. and an additional small compressor to take care of vapor at high back pressure from M. E. R 18% 4% Present compressor made M. E. C. with M. E. R. to take care of vapor from M. E. R. at high back pressure 21% 12% Present compressor with an additional com- pressor to take care of vapor from fore- cooler at high back pressure 43% 7% Present compressor with M. E. R. and an additional compressor to take care of vapor from forecooler and M. E. R 69% 10% Present compressor made multiple effect to take care of vapor from forecooler at high back pressure 43% 18% Present compressor made multiple effect with M. E. R. to take care of vapor from fore- cooler and M. E. R. at high back pressure 70% 25% Present compressor with engine changed from simple to compound non-condensing en- gine will use about 28% less steam. The ice manufacturer of the future, whether he makes can or plate ice, need no longer be tied down to the great losses of the present day. The can ice man can make up his distilled water with the use of a multiple effect still and the plate ice man has all the 138 THE ABSORPTION EEFEIGBKATING MACHINE water he wants anyway. (See table of ice making possibilities, p. 54, Eef. Mach. Comp. Abs.) It will be noticed that to run two old style com- pressors, one at high and one at low back pressure, would only save 7% of the power and that naturally has kept machine builders from generally so dividing the compressors for ice plants, as the saving is too small to bother with. But when 70% gain in capacity and 26% saving in power becomes possible by changing the present compressor to a M. E. C. and using a M. E. E., the matter would seem too attractive to let pass without most careful consideration. In most all application of refrigeration, the refrig- eration can be divided into high temperature refrigera- tion and low temperature refrigeration. The following are some of the gains for M. B. C. and M. E. K. for very much less horse-power per ton of refrigeration than if one compressor at the low back pressure were used, or if two common compressors were used at two back pressures : Increase of refrigeration M. E. C. and M. E. B. Brewery cellars and Baudelots 46% Ice making and brewery 70% Low temperature cold storage and Ice making 77% Air cooling for blast furnaces 102% Low temperature and high temperature refrigeration for cold storage or packing house 107% Street pipe line refrigeration and cooling offices and theaters. 197% In ice making it is evident that to cool water from, say, 100° to 32°, and freeze it into ice with liquid am- monia at 100°, if the water is cooled from 100° to 34° and the liquid ammonia is cooled from 100° to 15° without using any refrigeration at the low back pres- sure for this cooling of water and ammonia, the capac- ity of the compressor for freezing ice at the low back pressure will be greatly increased. Any make of compressor operated its present speed, whether single or double acting, retaining the same size piston and same length of stroke, changed to a THE ABSORPTION REFRIGERATING MACHINE 129 Multiple Effect Compressor and used in connection with a Multiple Effect Eeceiver, will then operate at two different hack pressures, a low back pressure the same as at present for freezing the ice and a higher back pressure to cool the water before it goes to the cans and to cool the liquid ammonia before it goes to the expan- sion valve. The gain in ice making capacity and saving in horse-power per ton of ice for various condensing water temperatures is as follows : Condensing water Per cent Increased Ice Per cent decreased h. p. temperature. making capacity. per ton ice. 100° 80% 35% 90° 70% 25% 80° 58% 22.6% 70° 48% 88% 20% 60° 17.5% 60° 29% 16% 130 THE ABSORPTION EEI'KIGEEATING MACHINE CHAPTEE XVIII. Voorhees' Multiple Effect Absorption System, Used with Voorheea' Multiple Effect Eeceiver. It is often desired to do refrigerating by taking up heat at two or more different planes of temperature. Such refrigeration has been done in the past either by taking up the heat at the lower plane of temperature or by employing as many different refrigerating ma- chines as there are planes of temperature. The Voorhees Multiple Effect Absorption System (patented) consists of an absorption apparatus having two or more sets of refrigerators and absorbers ar- ranged to maintain different pressures in the refrig- erators and absorbers so that the refrigeration may be done at two or more planes of temperature without requiring a complete absorption machine for each plane of temperature. The different pressures in the refrig- erators and absorbers are controlled by the tempera- ture and per cent of strength of the absorbent in the absorbers. For a given absorber temperature a low absorber pressure requires a less strength of absorbent than does a higher absorber pressure. Low tempera- ture in the refrigerator requires less absorber pressure than does high temperature in the refrigerator; and when the absorbent in an absorber is saturated with gas at a low pressure it will still have a capacity, even at a higher temperature, to absorb more gas at a higher pressure. In general, in an absorption ammonia system em- THE ABSORPTION REFRIGERATING MACHINE 131 bodying my invention, aqua ammonia from a single still by being exposed, seriatim, to ammonia gas in a series of absorbers, each absorber being at a higher pressure than the absorber before it in the circuit, can seriatim absorb more and more ammonia gas and be- come resaturated in each absorber. During absorption, the liquor which has absorbed gas in the lowest pressure absorber is passed to that absorber in which the next higher pressure is main- tained, and so on; though if preferred the several absorbers may be connected in parallel to the still so that different portions of the weak liquor from the still may pass through the several absorbers and may be discharged thence into the still from the several absorbers separately. This improved method and device requires much less apparatus than when refrigeration at a number of different temperature planes is conducted accord- ing to the prior methods, and there is a great saving in cooling water and steam, as well as a great saving in the first cost of apparatus. A Multiple Effect Eeceiver was fully described in Ice and Refrigeration (August and September, 1909), and it automatically partly evaporates and cools the liquid ammonia for the low pressure refrigerator with- out the use of cooling coils at the pressure of the high pressure refrigerator and so makes the ammonia of the low pressure system just that much more effective. An adaptation of the multiple effect absorption sys- tem and the M. E. R. is shown in the accompanying illustration, where 90° condensing water is used. As- suming that the reader is familiar with the common ab- sorption system, the illustration should practically ex- plain itself with this brief additional description. Heavy lines show new parts. Here 100° liquid anhy- drous ammonia flows past expansion valve A, where its pressure is reduced in the M. E. E. to 37 pounds. 132 THE ABSORPTION BEFEIGEEATING MACHINE SO that part of it evaporates and thus cools the balance to 24°. This 24° F. liquid ammonia flows through regu- lating valve B to the forecooler and through expansion valve C to the freezing tank coil. The gas from the freezing tank coil at 15 pounds pressure flows to the C D 90°. CON DEN3 I NGi WATER i CONDEMSER RECTIFIER ■»- 78^ MORE ICE — LOW PRESS. LK^. Pui I mi ]^ ■ ,t- . r*l S ■ ■ > HlGiH VOORHEES MOUTlPUE EFFECT ABSORPTION SYSTEM S[> MULTIPLE EFFECT RECEIVER low pressure absorber and the combined gases from the M. E. R. and forecooler at 37 pounds flow to the high pressure absorber. The forecooler cools the water from 100° to 34° and the freezing tank coil cools the brine to 16°, which freezes the water into ice and cools the ice to 16°; 20% weak liquor from the generator flows into the low pressure absorber and in absorbing THE ABSORPTION REFBIGERATING MACHINE 133 the 15-pound gas becomes 30% liquor, and is pumped by the low pressure liquor pump to the high pressure absorber (in place of, as of old, via the dotted line to the exchanger). This 30% liquor now absorbs the 37- pound gas in the high pressure absorber and becomes 36% liquor and is then pumped by the high pressure pump to the generator via the exchanger and analyzer as of old. We see the M. E. R. cooled the liquid ammonia from 100° to 24° and the forecooler cools the water from 100° to 34°, both at 37 pounds back pressure and so take just that much refrigerating load off the low pressure apparatus so it can do just that much more freezing. Formerly 14% of the refrigeration was used to cool the ammonia from 100° to 24° and 30% to cool the water from 100° to 34° at 15 pounds back pressure. Now all the refrigerating capacity of the low pressure system is devoted to freezing ice, whereas of old only 56% was so devoted. Therefore the old absorber, ex- changer, liquor pump, generator, etc., will, with the M. E. R. and the high pressure absorber and liquor pump, do 100% of freezing; therefore 100 -r-. 56 = 1.78, i. e., the low pressure apparatus will now make 78% more ice. The following table shows what gains in ice making can be had by the addition to the old absorption system of an extra absorber and liquor pump and a multiple effect receiver for various temperatures of condensing water: % More Ice by Temp. Cond. Water. M. B. A. & M. E. R 100° 94% 90" 78% 80° 63% 70° *9% 60° 37% B0° 26% Any absorption machine, as for ice making, cold storage or any other purpose, can be made "Multiple Effect" and its capacity greatly increased by installing an extra absorber and liquor pump under this patent. 134 THE ABSOEPTION HEFRIGERATING MACHINE CHAPTBK XIX Useful Tables COMPARISON OF FAHRENHEIT AND CENTEGRADE THER- MOMETER SCALES. °p. "C. °E. "0. °F. °C. °P. °C. °F. °C. "P. °C. 330 165.6 267 130.6 206 96.7 143 61.7 80 26.7 19 - 7.2 329 165. 266 130. 205 96.1 142 61.1 79 26.1 18 - 7.8 S28 164.4 265 129.4 204 95.6 141 60.6 78 25.6 17 - 8.3 327 163.9 261 128.9 203 95. 140 60. 77 25. 16 - 8.9 326 163.3 263 128.3 202 94.4 139 59.4 76 24.4 15 - 9.4 325 162.8 262 127.8 201 93.9 138 58.9 75 23.9 14 -10. 324 162.2 261 127.2 200 93.3 137 58.3 74 23.3 13 -10.6 323 161.7 260 126.7 199 92.8 136 57.8 73 22.8 12 -11.1 322 161.1 259 126.1 198 92.2 135 57.2 72 22.2 11 -11.7 321 160.6 258 125.6 197 91.7 134 66.7 71 21.7 10 -12.2 320 160. 257 125. 196 91.1 133 56.1 70 21.1 9 -12.8 319 169.4 256 124.4 195 90.6 132 55.6 69 20.6 8 -13.3 318 168.9 255 123.9 194 90. 131 55. 68 20. 7 -13.9 317 158.3 254 123.3 193 89.4 130 54.4 67 19.4 6 -14.4 316 157.8 253 122.8 192 88.9 129 53.9 66 18.9 5 -15. 315 157.2 252 122.2 191 88.3 128 53.3 65 18.3 4 -15.6 3U 156.7 251 121.7 190 87.8 127 52.8 64 17.8 3 -16.1 313 156.1 250 121.1 189 87.2 126 52.2 63 17.2 2 -16.7 312 155.6 249 120.6 188 86.7 125 51.7 62 16.7 1 -17.2 311 155. 248 120. 187 86.1 124 61.1 61 16.1 -17.8 310 154.4 247 119. 4 186 85.6 123 60.6 60 15.6 - 1 -18.3 309 153.9 246 118.9 185 85. 122 50. 69 15. - 2 -18.9 308 153.3 245 118.3 184 84.4 121 49.4 58 14.4 - 3 -19.4 307 152.8 244 117.8 183 83.9 120 48.9 57 13.9 - 4 -20. 306 152.2 243 117.2 182 83.3 U9 48.3 56 13.3 - 5 -20.6 305 151.7 242 116.7 181 82.8 118 47.8 55 12.8 - 6 -21.1 304 151.1 241 116.1 180 82.2 117 47.2 54 12.2 - 7 -21.7 303 150.5 240 115.6 179 81.7 116 46.7 63 11.7 - 8 -23.2 302 150. 239 115. 178 81.1 115 46.1 52 11.1 - 9 -22.8 301 149.4 238 114.4 177 80.6 114 45.6 51 10.6 -10 -23.3 300 148.9 237 113.9 176 80. 113 45. 50 10. -11 -23.9 299 148.3 236 113.3 175 79.4 112 44.4 49 9.4 -12 -24.4 298 147.8 235 112.8 174 78.9 111 43.9 48 8.9 -13 -25. 297 147.2 234 112.2 173 78.3 110 43.3 47 8.3 -14 -25.6 296 146.7 233 111.7 172 77.8 109 42.8 46 7.8 -15 -26.1 295 146.1 232 111.1 171 77.2 108 42.2 45 7.2 -16 -26.7 294 145.6 231 110.6 170 76.7 107 41.7 44 6.7 -17 -27.2 293 145. 230 110. 169 76.1 106 41.1 43 6.1 -IS -27.8 292 144.4 229 109.4 168 75.6 105 40.6 42 5.6 -19 -28.3 291 143.9 228 108.9 167 75. 104 40. 41 5. -20 -28.9 290 143.3 227 108.3 166 74.4 103 39.4 40 4.4 -21 -29.4 289 142.8 226 107.8 165 73.9 102 38.9 39 3.9 -22 -30. 288 142.2 225 107.2 164 73.3 101 38.3 38 3.3 -23 -30.6 287 141.7 224 106.7 163 72.8 100 37.8 37 2.8 -24 -31.1 286 141.1 223 106.1 162 72.2 99 37.2 36 2.2 -25 -31.7 285 140.6 222 105.6 161 71.7 98 36.7 35 1.7 -26 -32.2 284 140.0 221 105. 160 71.1 97 36.1 34 1.1 -27 -32.8 283 282 139.4 138.9 220 104.4 159 158 70.6 70. 96 95 35.6 35. 33 0.6 -28 -33.3 219 103.9 Water freezes —29 —33.9 281 138.3 218 103.3 157 69.4 94 34.4 -30 -34.4 280 137.8 137.2 217 216 102.8 102.2 156 155 68.9 68.3 93 92 33.9 33.3 32 0. -31 —32 —35. 279 31 -0.6 -35.6 278 136.7 215 101.7 154 67.8 91 32.8 30 -1.1 —33 -36.1 277 136.1 214 101.1 153 67.2 90 32.2 29 -1.7 —34 -36.7 276 275 135.6 135. 213 100.6 152 151 66.7 66.1 89 88 31.7 31.1 28 27 -2.2 -2.8 -35 -37.2 \tT A _ l..^1_ —36 —37.8 274 134.4 Wattr boils 150 65.6 87 30.6 26 -3.3 —37 -38.3 273 133.9 133.3 212 100. 149 148 65. 64.4 86 85 30. 29.4 25 24 -3.9 -4.4 -38 —39 —38.9 272 211 99.4 -39.4 271 270 132.8 132.2 210 209 98.9 98.3 147 146 63.9 63.3 84 83 28.9 28.3 23 22 -5. -5.6 leresry 269 131.7 208 97.8 145 62.8 82 27.8 21 -6.1 freezes 268 131.1 207 97.2 144 62.2 81 27.2 20 -6.7 -40 -04 THE ABSORPTION REFRIGERATING MACHINE 135 COMPARISON OF CENTEGRADE, FAHRENHEIT AND REAUMUR SCALES. 0. F. R. C. F. R. C. F. R. +100° + 212.0° +80.0° +53° +127.4° +42.4° + 6° +42.8° +i-T 99 210.2 79.2 52 126.6 41.6 B 41.0 4.0 98 208.4 78.4 51 123.8 40.8 4 39.2 3.2 97 206.6 77.6 50 122.0 40.0 3 37.4 2.4 96 204.8 76.8 49 120.2 39.2 2 35.6 1.6 95 203.0 76.0 48 118.4 38.4 1 33.8 0.8 94 201.2 75.2 47 116.6 37.6 Zero 32.0 2;ero 93 199.4 74.4 46 114.8 36.8 - 1 30.2 - 0.8 92 197.6 73.6 45 113.0 36.0 2 28.4 1.6 91 195.8 72.8 44 111.2 35.2 3 26.6 2.4 90 194.0 72.0 43 109.4 34.4 4 24.8 3.2 89 192.2 71.2 42 107.6 83.6 B 23.0 4.0 88 190.4 70.4 41 105.8 32.8 6 21.2 4.8 87 188.6 69.6 40 104.0 32.0 7 19.4 5.6 86 186.8 63.8 39 102.2 31.2 8 17.6 6.4 85 185.0 68.0 38 100.4 30.4 9 15.8 7.2 84 183.2 67.2 37 98.6 29.6 10 14.0 8.0 83 181.4 66.4 36 96.8 28.8 11 12.2 8.8 82 179.6 65.6 35 95.0 28.0 12 10.4 9.6 81 177.8 64.8 34 93.2 27.2 13 8.6 10.4 80 176.0 64.0 33 91.4 26.4 14 6.8 11.2 79 174.2 63.2 32 89.6 25.6 15 6.0 12.0 78 172.4 62.4 31 87.8 24.8 16 3.2 12,8 77 170.6 61.6 30 86.0 24.0 17 1.4 13.6 76 168.8 60.8 29 84.2 23.2 18 -0.4 14.4 75 167.0 60.0 28 82.4 22,4 19 2,2 1S.2 74 165.2 59.2 27 80.6 21.6 20 4.0 16.0 73 163.4 58.4 26 78.8 20.8 21 5.8 16.8 72 161.6 B7.6 25 77.0 20.0 22 7.6 17.8 71 1B9.8 56.8 24 75.2 19.2 23 9.4 18.4 70 158.0 56.0 23 73.4 18.4 24 11.2 19.2 69 156.2 55.2 22 71.6 17.6 25 13.0 20.0 68 154.4 64.4 21 69.8 16.8 26 14.8 20.8 67 152.6 63.6 20 68.0 16.0 27 16.6 21.6 66 150.8 52.8 19 66.2 15.2 28 18.4 22.4 65 149.0 52.0 18 64.4 14.4 29 20.2 23.2 64 147.2 61.2 17 62.6 13.6 30 22.0 24.0 63 145.4 60.4 16 60.8 12.8 31 23.8 24.8 62 143.6 49.6 IB 59. 12.0 32 25.6 25.6 61 141.8 48.8 14 57.2 11.2 33 27.4 26 4 60 140.0 48.0 13 B5.4 10.4 34 29.2 27.2 69 138.2 47.2 12 53.6 9.6 35 31.0 28.0 68 136.4 46.4 11 B1.8 8.8 36 32.8 28.8 B7 134.3 45.6 10 BO.O 8.0 37 34.6 29.6 66 132.8 44.8 9 48.2 7.2 38 36.4 30.4 65 131.0 44.0 8 46.4 6.4 39 38.2 31.2 64 129.2 43.2 7 44.6 B.8 40 40.0 32.0 °R, CONVERSION OP THERMOMETER DEGREES. multiply by 4 and divide by 5. °C to "C to "F, multiply by 9, divide by 5, then add 32. "R to "C, multiply by 5 and divide by 4. "R to "F. multiply by 9, divide by 4, then add 32. "F to "R, first subtract 32, then multiply by 4 and divide by 9. OF to "C, first subtract 32, then multiply by B and divide by 9. 136 THE ABSORPTION EEFEIGEKATING MACHINE PROPERTIES OF SATURATED AMMONIA— (Wood) Tempera- ture. Pressure, absolute. III r ■tfa ro-w 1. I! 1^ Is ■0 pp. > J 3" u ft.S 1* It 1 - 40 - 35 - 30 420.66 425.66 430.66 1540.9 1773.6 2035.8 10.59 12.31 14.13 579.67 576.69 573.69 48.23 48.48 48.77 631.44 528.21 524.92 24.37 21.29 18.66 .0234 .0236 .0237 .0410 .0467 .0635 - 25 - 20 - 15 435.66 440.66 445.66 2329.5 2657.5 3022.5 16.17 18.45 20.99 570.68 567.67 564.64 49.06 49.38 49.67 521.62 518.29 514.97 16.41 14.48 12.81 .0238 .0240 .0242 .0609 .0690 .0779 -10 - 5 450.66 4B5.66 460.66 3428.0 3877.2 4373.5 23.77 25.93 30.37 561.61 658.56 556.50 49.99 50.31 50.68 511.62 508.25 604.82 11.36 10.12 9.04 .0243 .0244 .0246 .0878 .0988 .1109 + B + 10 + 15 465.66 470.66 475.66 4920.5 5522.2 6182.4 34.17 38.55 42.93 553.43 549.35 546.26 50.84 61.13 51.33 501.69 498.22 494.93 8.06 7.23 6.49 .0247 .0249 .0250 .1241 .1384 .1640 + 20 + 25 + 30 480.66 485.66 490.66 6905.3 7695.2 8B96.0 47.95 53.43 59.41 543.15 540.03 536.92 51.61 51.80 52.01 491.54 488.23 484.91 5.84 5.26 4.75 .0252 .0253 .0254 .1712 .1901 .2105 + 35 + 40 + 45 49B.66 500.66 505.66 9493.9 10512 11616 65.93 73.00 80.66 533.78 530.63 527.47 52.22 52.42 52.62 481.56 478.21 474.85 4.31 3.91 3.56 .0256 .0257 .0260 .2320 .2583 .2809 + 50 + 55 + 60 BIO. 66 B1B.66 B20.66 12811 14102 15494 88.96 97.93 107.60 524.30 521.12 517.23 52.82 53.01 53.21 471.48 468.11 464.72 3.25 2.96 2.70 .0260 .0260 .0265 .3109 .3379 .3704 + 65 + 70 + 75 525.66 530.66 535.66 16993 18605 20336 118.03 129.21 141.25 514.73 611.52 508.29 53.38 53.57 53.76 461.35 457.85 454.53 2.48 2.27 2.08 .0266 .0268 .0270 .4034 .4405 .4808 + 80 + 85 + 90 540.66 545.66 550.66 22192 24178 26300 154.11 167.86 182.8 504.66 501.81 498.U 53.96 54.15 54.28 450.70 447.66 443.83 1.91 1.77 1.64 .0272 .0273 .0274 .5252 .6649 .6098 + 95 +100 +105 555.66 560.66 565.66 28565 30980 33550 198.37 215.14 232.98 495.29 491.50 488.72 54.41 54.54 64.67 440.88 436.96 434.08 1.51 1.39 1.289 .0277 .0279 .0281 .6622 .7194 .7757 +110 +115 +120 570.66 575.66 580.66 36284 39188 42267 251.97 272.14 293.49 485.42 482.41 478.79 54.78 54.91 55.03 430.64 427.40 423.76 1.203 1.121 1.041 .0283 .0285 .0287 .8312 .8912 .9608 +125 +130 +135 585.66 590.66 595.66 45528 48978 52626 316.16 340.42 865.16 475.45 472.11 468.75 65.09 55.16 65.22 420.39 416.94 413.53 .9699 .9061 .8457 .0289 .0291 .0293 1.0310 1.1048 1.1824 +140 +145 +150 600.66 605.66 610.66 55483 60550 64833 392.22 420.49 450,20 465.39 462.01 458.62 65.29 55.34 55.39 410.09 406.67 402.23 .7910 .7408 .6946 .0295 .0297 .0299 1.2642 1.3497 1.4696 +1BB +160 +166 615.66 620.66 625.66 69341 74086 79071 481.54 514.40 549.04 455.22 451.81 448.39 55.43 55.46 55.48 399.79 396.35 392.94 .6511 .6128 .5765 .0302 .0304 .0306 1.5358 1.6318 1.7344 The critical pressure of ammonia is 115 atmospheres; critical temperature at 266° F. (Dewar) ; critical volume .00482 (calcu- lated). THE ABSOUPTION KEFRIOEKATING MACHINE 137 PROPERTIES OF SATURATED AMMONIA. CALCnLATBD FROM THE ORIGINAL FORMULA OF PROF. DB VOLSON ■WOOD BT OEO. DAVIDSON, M. E. Compiled especially for and originally published In Ice and Refrigeration tor December, 1904. Tempera- Pressure, h •Ed sj . 1- a ^ d ture. absolute. P % p.* ad Op ■0 S3 1 ^ ^ 1^ §.»• s . *•* «d «« Pi :§2 o . o . B. Author of "Indicatimg the Befriaeratino Machine" and *'27ie Absorption Mefrigeraiina Machine" 'PHIS BOOK has much data in a form that is applicable -^ to practically all problems of capacity and economy of refrigerating machines and it should be of great value to all engineers, salesmen and owners of refrigerating machines. It is a complete treatise on the vital features of compression and absorption machines and their com- binations, and the operation of their various parts. Price: Bonnd in Cloth, $2.00. Fnll Morocco, $2.50. l!Se by Nickerson & Collins Co. ^'i.'^A'^rTL!!: THE ABSORPTION REFBIGERATINQ MACHINE 157 2! Recognized Authority in all matters relating to Mechan- ical Refriger- ation A MONTHLY REVIEW of the Ice, Ice Making, Refrigerating, Cold Storage and kindred trades TEEE oldest publication of its kindin the world, and the only medium through which can be obtained all the reliable technical and practical information re- latingtotheacienceofmeohanicalicemakin^andrefrigeration. ICE AND REFRIGERATION is invaluable to anyone owmng or operating, or in any way intorested in ice making or refrigerating machinery. It has won the confidence of all classes of the trade throughout the world by its absolute independence and im- partiality. It aims to bea thoroughly lepresentatire paper, catering to no partic- ular class, but striving to become indispensable toall. 1 1 is not shackled by any pet theoriea.andnomanorclassofmenhaa any private pull with it. Its columns are open to the entire trade: to anyone who has anything of mterest or value to say. SUBSCRIPTION PRICE In U. S., Canada and Mexico, $2.00 per year In all other countries, - - - 3.00 per year Payable in advance. Remit by post office or express vioney orders, or 6y bank dr^ft on Chicago or New York. NICKERSON & COLLINS CO. PtjBUSHERB Chicago, U. S. A. 158 THE ABSOKPTION REFRIGERATING MACHINE By the Author of 'Indicating the Refrigerating The Absorption T-k n • J • Refrigerating Keiris^eratin g; Machine and O ' O "Refrigerating -« y|- -I • Machines* MaCnine compression, ___^_^_^^^____ Absorption. By GARDNER T. VOORHEES, S. B. A complete, practical, elementary treatise of the absorption system of refrigeration, and its broad general principles of operation, showing also_ its development. Profusely illustrated with original drawings by the author. ni>Tr>r< 3 Bound in Clotli^ $2.00 *^^^^^ ] Bound inFullMorocco,. . . 2.60 Sent prepaid to any address upon receipt of price. NICKERSON & COLLINS CO., Publishers CHICAGO, U. S. A. Indicating- the ofthei^lctfoftolre Ammonia Compressor ipr En -|-k C * A * *"^ oteam isngine K Plfl OTf^Tft T1 n O" wi* Practica 1 Instruc- -^^^■'-'-■'^S^^**'-'^-"6 tions Relating to the ■~~~~~— ^~^~^^^^"^^^^~"' Construction and Use "\T_._1_;,__ _of the Indicator and iVlaCnlne Reading and Comput- ^_^^_^__^_^^_ ing Indicator Cards, ing . By GARDNER T. VOORHEES, S. B. The book contains a simple elementary description of the Indicator and Simple Practical Tables for apply- ing the true^ compression .curve to the Indicator Card. So simple are these tables that any man competent to run a compressor can use them. PnTPTT J Bound in Cloth $1.00 ""*'*' (Bound in Flexible Morocco, . 1.60 Sent prepaid to any address on receipt of price NICKERSON & COLLINS CO., Publishers CHICAGO, U.S. A. THE ABSORPTION UEFUIGERATING MACHINE 159 GardnerT.Voorhees Refrigerating Engineer and Arcliitect S. B. Massachusetts Institute of Technology, Class of '90, Member of the American Society of Mechan- ical Engineers, Member of the American Society of Refrigerating Engineers. Best possible refer- ences given. MECHANICAL REFRIGERATION In All Its Applications, as Cold Storage Warehouses, Ice Fac- tories, Street Pipe Line Refrigera- tion, Breweries, Factories, Hotels, Clubs, Hospitals, Office Buildings, Theatres, Banks, Skating Rinks, Etc., Etc. EXPERT WORK, TESTS, APPRAISING, ETC ETC. 53 STATE STREET (Cable Address. "Coldmaker"] Boston, Mass. : : U. S. A. JJ 160 THE ABSORPTION EBFEIGEEATING MACHINE DE LA VERGNE MACHINE CO. Manufacturers of COMPRESSION REFRIGERATING MACHINES IN SIZES FROM 5 TO 600 TONS CAPACITY 600 TON HORIZONTAL MACHINE FOR GOOD REASONS, BASED ON PRACTICAL EXPERIENCE WE ADVOCATE THE USE OF AMMONIA COMPRESSION REFRIGERATING MACHINERY IN ALL CASES WHERE MECHANICAL REFRIGERATION IS REQUIRED DE LA VERGNE MACH. CO. 1 1 38 EAST 1 3STH STREET NEW YORK Missing Page g CQ n o 69 O i 9' a el" 2.2 - M ^ 50.0 eg-p- i|§ 11 »■ ig.e C Eh OS f 1 S" S. H I I g'' a? 2 S.S. s » » ffig p a 2 "■ «■ an P c+ p o IV fv ^ °p ?«! ;3.i- £=2 ^ A U O ? s. P 'O o P" o g. re P" ^1 pi s* <» re 5 P PS— ffiffi B re "^ u M r^ r* , P* e o OB ^ < ' A A {B HI H o 3 O a 1 £ 2 M CO g 01 ca (t) > ^ o 3 ■-0 •Ti 5' W »3 o -i Cfl ca. D > sr M Pi e S 3 o 9 09 > e Ammonia V^es and Fittings \ For the trade a specialty We manufacture all of the con- stituent parts, and are therefore able to guarantee uniform excel- lence in all parts of the plant. Branch Offices in all the Principal Cities General Western Office: Monadaock .Block Chicago . York Manufacturing Co. Main Office and Works YORK, PA. YORK MANUFACTURING CO. The Largest Ice Machine iManufacturers in the World We Build Both Absorption and Compression Systems Absorption Plants Of either Exhaust Steam or High Pressure Type Compression Plants Of either Vertical Single -Acting or Horizontal Double-Acting Compressors • * » Generator and Analyzer All seams welded and shell flanged over steel rings to form male and female joints with heads.