Abstract: A fish extract having a high nutritive value and being free of fish smell and bitterness is advantageously obtained when fish bodies are directly charged in a reaction vessel without subjecting them to the conventional cutting and slurrying treatments and are treated with two kinds of proteinases at different pH values of 9 to 10 and of 5 to 6 at 50.degree. to 60.degree. C.

Abstract: This invention relates to a box, particularly suited for the packing of a quadrangular object and a method of manufacturing the same. The box of this invention is made of elements including a sheet of paperboard in such way that the cover can be freely opened and closed.

Abstract: Yeast is produced by fermenting hydrocarbons in an aqueous nutrient medium which includes sulfate, chloride and phosphate ions. When the fermentation is completed the nutrient medium has become depleted in mineral content and a large portion of it is purged. A calcium source is added to precipitate the phosphate ion out as calcium phosphate. The precipitated calcium phosphate is added to the yeast, which in itself is an excellent source of protein. The resulting product is suitable for use as an enriched animal feed. Meanwhile the removal of the phosphate ion eliminates a pollutant from the purge stream.

Abstract: This disclosure teaches a direct fired heater with a double casing. The double casing includes a somewhat conventional inner casing having a burner penetrating therethrough and an outer casing spaced from the inner casing to form a passage in flow communication between the atmosphere and the burner. The outer casing surrounds the burner and is provided with an acoustic inner surface to minimize escape of noise. Design of refractory linings with respect to thickness and density allows for maintenance of skin temperature of the inner casing above the condensation ranges of SO.sub.2 and SO.sub.3.