GB999467A - Improvements in the storage of perishable animal and vegetable materials and apparatus therefor - Google Patents

Abstract

999,467. Storing animal and vegetable materials. WHIRLPOOL CORPORATION. May 9, 1963 [July 2, 1962], No. 25279/62. Heading A2D. [Also in Division B1] Perishable animal and vegetable materials subject to respiratory deterioration changes on storage in air containing normal quantities of oxygen and carbon dioxide are stored in an atmosphere containing an amount of carbon dioxide greater than that found in ambient air and an amount of oxygen less that that found in ambient air, which atmosphere is produced by burning a carbonaceous fuel in the presence of air in amounts necessary to support substantially complete combustion of the fuel and at a combustion temperature that is beneath the temperature of reaction of oxygen with the nitrogen of the air to prevent formation of oxides of nitrogen, and is passed to a non gas-tight storage chamber for the materials where it continuously replenishes atmosphere escaping from the chamber. Animal and vegetable materials mentioned: apples, grapes, berries, tomatoes, peaches, pears, oranges and bananas; potatoes, carrots, celery, asparagus, onions, beans and peas; milk, butter, cheese and eggs; meat and meat products; grains, nuts, cut flowers, flower bulbs and tobacco. Under preferred conditions, the storage chamber is refrigerated, the atmosphere has 25-100% relative humidity (preferably 85-100%), a temperature between 29‹ and 120‹F. (preferably 29-55‹F.), 1-10% by volume oxygen and 1-15% by volume carbon dioxide. The amount of carbon dioxide may be regulated by passing the atmosphere through a scrubbing tower. A cylindrically-shaped catalytic burner 14, Fig. 2, for the combustion of the mixture of air and vapourised hydrocarbon fuel at a temperature in the range from 1200‹ to 2000‹F., below that at which substantial amounts of nitrogen oxides are formed, has an annular catalytic bed 36 mounted between perforated stainless steel annuli 34, 35, an inlet 28 for the mixture, an outlet 15 for the combustion products and an igniter 41. The air and gaseous fuel are pre-mixed by a blower to provide 20-25% excess air over that required for combustion. Ignition at first takes place within the space 40 until this heats the catalytic bed 36 to a temperature high enough to support combustion. The temperature at which the combustion reaction takes place is regulated by circulation of water in a jacket 37. This water may have been previously employed in chilling the flue gas produced. Catalysts mentioned are chromealumina containing 20% chromic oxide in the form of #-inch extruded pellets and platinum-alumina.