Complete Text (Part 16)

are provided with hooks and such other devices as are necessary for the hanging of meats, and are rented to the butchers by the year. Certain 96 w. ICE .«. AND .. REFRIGERATION .°. AUGUST, 1893. hours are stipulated during which the meats can be stored or removed, no access to the storage being al- lowed in the intervals. As it can be seen in the figures, the air blower Vis in close connection with the ‘air cooler,” its aspiration desired through the flue P, which can be put in connec- tion with the aspiration of the blower, and any vitiated air can be evacuated by pipe G (Fig. 1.). The discharg- ing pipe 4 A of the blower (Figs. 1, 2, 3, 4) has a diame- ter of 2 feet 8 inches, about; the exhausting pipe C C of 3 1fig. Section By AB. 7 = —- 3 = in Fy : Return of warm ae Blower ; = eon a ae ee Pte aS; if ae ah oe Yy Atr cooler Diveck Expansion Coiks c! c ZZ YS : Hl i 2 SS — 5 1 | oa CREFELD COLD STORAGE TypeN’s. System Fixavy. Gener yp stern fsa 4 af dispositions of oler and pipes ie ” 7 ff Mix cooking Opparatus. or SE Sere Steam Engine Gas pump (ice machine Ye Yj, Wi nol a 7 coldair Meat Repat Plan -fig2. causing the warm air of the meat room to pass through the cooler before it can be discharged again, dried and cooled, in the room. Whenever it is judged necessary to introduce fresh air from the outside for purposes of ventilation or any other, it can be supplied to any extent feet, nearly. The ice and refrigerating machine hasa ca- pacity of 34,000 thermal units per hour. Besides cool- ing the air it produces 825 pounds of ice per hour. The ‘air cooler” is of a peculiar construction. It was invented by Mr. Fixary, and is used not only in AUGUST, 1893. 97 this storage but in those of Lisbon, Brussels, Cologne and many others. The Fixary arrangement may be properly called an ‘‘Exchanger of Temperatures.” It acts very much like what is called a ‘‘ Regenerator” in a heat engine, the very formation of the last being taken advantage of to produce the useful results. As we have already said, it applies to systems of cold-making in which the volatile liquid is directly expanded in coils, or any other contrivance, without the intermediary of brine. The apparatus consists essentially of the coils /, /’ (Fig. 5), which are enclosed in the compartments C, C’ of a wooden ‘box B, perfectly insulated. These coils are made to communicate alternately with the aspiration of the gas pump of the ice machine by means of proper pipes and devices. For instance, the coil /’ being in operation, the volatile liquid—liquefied gas ammonia, figs : Longitudinal Section by its passage around the active coil /’, on the surface of which its moisture is deposited as frost. When this coil J is covered with frost, the position of the cocks R, R' and of the valves Vand /’ is simultaneously re- versed, the closing of # and opening of R’ making of 7 the active coil and of 7’ the inactive one; but by the change in the valves V and V’', the warm current of air from the rooms is directed first from 4 to C’ in which it circulates around the now inactive but frost covered coil 7’ from top to bottom, passing then into C, around the now active coil /, to be then further cooled before it returns finally through 4' to the meat room. When this coil / is, in its turn, covered with frost, things are brought back to their original state, and so on. In this manner, the warm air from the rooms is first brought in contact with the inactive frost covered coil, thus cov- ered by a preceding operation; it begins to cool there Fig. Plan ofmeat room. mL ’. “Ve Op SAS |ée in mw ts | 7A CREFELD COLD STORAGE General disposhions of meat room a ancreulohon for instance—is admitted by the pipe 4 through the expanding valve din this coil /’, the cocks R, R being so disposed and arranged that the opening of one or the other directs the liquid in one coil or the other. The volatile liquid, the liquefied ammonia in this case, expanded and, by this expansion, having produced cold, returns to the pump as gas (Fig. 2) by the pipe 4’ to be compressed and liquefied again by cooling in the condenser, as is usual in this class of mechanical com- pression machines. The warm air, exhausted or as- pirated from the meat room by the blower, is discharged in the air cooling apparatus in A (Fig. 5), traverses the compartment C from top to bottom around the inactive coil J, previously covered with frost by a freezing oper- ation, then enters the compartment C’, toward which it is directed by the action of the valves V andV’, and then returns to the room through 4’ after having been cooled by melting the frost of the coil, being further and more completely cooled by its passage around the active coil, of which the surface is free from frost, the water result- ing from the thawing out of the frost being evacuated by the purging cocks . By this disposition, as it can be seen, the frost formed on the cold metallic surface by the condensation of the moisture of the air is taken advantage of to cool and deprive of moisture, to a certain extent, a fresh quantity of air. The air is in continuous circulation; its velocity is small, and it is thoroughly dried, cooled and purified outside of the meat room be- fore it returns to it. In fact, the ‘‘air cooler” is, so to speak, a ‘‘double expander,” one-half of which only is in operation at a time, the other getting ready to be utilized by its frost being thawed out. In cases when the temperature of the air should * See E, Fixary’s patent, No, 330,884, Novembes 24, 1885, 98 «. ICE ... AND .*. REFRIGERATION .-. AUGUST, 1893. have to be éc/ow the freezing point, that is, were the meats to be congealed, or for some other applications, it is obvious that the thawing out of the frost on the coil, which has been active, could not be obtained by passing the returning air from the rooms around it. In this case, the thawing out is secured by suppressing completely the circulation of the air around the frost covered coil by the closing of proper valves, and directing it around the other coil, made then the active coil, while the working of proper cocks admits én the snow covered coil a certain amount of hot compressed gas as it escapes from the pump in its way to the condenser of the machine. In this case, of course, the cold which has produced the frost is lost, but the surfaces are kept clean. Temperatures of air of —12°C. (10° to 11° F.) have been readily ob- tained in Germany, it is claimed, by this method. The experiments made by the syndicate of the Paris butchers, by the butchers of Brussels and Cologne, the extensive and detailed official reports which they have published on this question, have proved, theyclaim, that by this system it has been possible ‘to preserve for many weeks meats and other perishable articles without freezing them, a practice which deteriorates the fibers and destroys, to quite an extent, the nutritious palatable qualities of meats "—<‘that, in case tempera- tures below freezing point are required, this system gives equally satisfactory results.” Resume.—We have come to the end of this rapid ex- amination. We can sum up as follows: None of the installations described can, in any man- ner, compare as to importance with the immense cold storage and packing houses of this country. They are more particularly intended for the daily wants of a com- paratively small population, or a portion of a large one. However, certain principles and practices seem to have been followed very uniformly, and that, too, in France as well asin Belgium, Portugal and Germany, and to have given very satisfactory results which cannot be ignored, as they have been vouchsafed by hypercritical author- ities. First, Air is the constant vehicle of cold resorted to. Second, Air thoroughly dried and cold is the ultimate agent of conservation, its temperature being confined within a few degrees above the freezing point. Third, There is no piping in the meat room. The air may be cooled by different contrivances, but it is invariably cooled in special rooms, distinct {rom the meat room. Fourth, The circulation of the air is considered an essential feature. It is obtained either naturally by the difference in the specific gravity of the air at different temperatures or artificially by means of a blower, but, in all cases, the velocity of the current is very small. We see also, that, without an exception, the prac- tice recommended by Tellier is followed. The lowering of temperature of the air does not reach below 30° F. It seems to be a confirmed opinion of the continental engineers that meats should not be frozen. In fact, the conditions of the installation do not seem to require the congelation. The meats, at least in all the examples we have quoted, are brought on foot to the abattoirs; they are there slaughtered and removed to the cold storage a few hours after, or, at any rate, they are not intended for transportation at a long distance after slaughtering, and the time during which they have to be preserved is limited to the wants of a market, one week at the most. It is certain, at all events much safer and satisfactory, that, within these limits and in such con- ditions it will be always preferable and cheaper and safer in order to insure to the preserved meats all the mer- chantable and palatable quality of fresh meats, not to carry the cooling to the point of congelation. As to the mode adopted to cool the air, the use of a cold brine spray (Schroeder system, first type) has certainly some advantage, as avoiding the formation of frost of the other methods; but it is certainly more cumbrous, it re- quires much more room and to a certain extent it goes against its object, which is to obtain dry air. There is likely to be some danger of the air charging itself with saline particles in solution mechanically carried by the current of air. The system is not as clean and neat as when the air is cooled by its contact with cold metallic surfaces. It is true that the condensation of the moist- ure, as frost, on these surfaces has the disadvantage of diminishing the conductibility of co/d from the cold pro- ducing agent to the air; but if we adopt ‘‘é fo/o” the statements of certain continental engineers, the use of very effective devices can obviate this inconvenience. It is one which is not so serious, if we consider the comparatively high temperature of the air, which it is not intended to underreach. Undoubtedly, the pipe system in the rooms, as practiced in breweries and cold storages here and elsewhere, admits of a greater exten- sion of application on a larger scale, the room is better utilized, and, for that matter, the air of the rooms is fully as dry and pure as with other dispositions more cum- brous and expensive. Let the volatile liquid be ex- panded directly in the pipes of the cellar, or let cold brine be circulated in their interior; it is always possible to regulate the temperature, at pleasure, by speeding or slacking the refrigerating machine. Air can just as well be renewed, if desired, by the opening of proper venti- lating flues. The objections of the condensation of the moisture as hoar frost on the cold pipes, condensation which certainly taxes unduly the production of the machine, is the only one to be considered in the case, it seems to us. It remains for whatever it may be worth on the point of economy. The practice of freezing the meats, however, is far from being absolutely condemned in Europe. In the ‘Official Report” which we have quoted, in France, it is at least advised strongly, if not absolutely recommended, whenever meats will have to undergo a transportation involving many days or weeks after slaughtering. When once congealed, meats should be kept in that state, their thawing out at any time (excepting for the purpose of salting) being like- ly to produce a deterioriation of the quality. If such practice is resorted to the meat should be completely frozen throughout. This freezing of the meats, and their subsequent thawing out, if properly, gradually and carefully conducted by experienced hands, will not prac- tically change their nutritious, and but slightly,if at all, their merchantable qualities. We have seen stated in the report mentioned that sheep transported from La Plata in this frozen state had been sold in Paris like fresh meat. As regards beef carcasses the difficulty ap- pears to be in their size. Even if success has been, or can be, obtained otherwise, the recommendations of the commission, however, must not be disregarded. The dressing and quartering of the larger meats in pieces not very voluminous, though it may necessitate more