Abstract: Disclosed is a continuous filter comprising a chamber provided with a cylindrical upper portion and a conical lower portion and having at its upper end portion a feed opening for a slurry to be filtered and at its lower end portion a discharge opening for the filtration cake, a porous support disposed inwardly of, and spaced from, the side wall of the chamber, a filter medium provided on the porous support, an outer annular filtrate-collecting space and an inner, slurry- and cake-holding space defined by the porous support, an agitation shaft extending from the slurry feeding end portion to the cake discharge end portion through said slurry- and cake-holding space, and a spiral or vane-like blade on the agitating shaft for shaving the cake on the filter medium and moving it to the discharge end portion of the chamber.

Abstract: A low temperature food drying process dries foods to the substantially absolutely dry state without deterioration by using a low humidity drying gas. This process comprises, in combination, the steps of (a) contacting a food with a low humidity drying gas having a dew point of -75.degree. to 0.degree. C., to dry the food at a temperature less than 60.degree. C., (b) passing the water-containing gas discharged from the step (a) through an adsorbing bed capable of adsorbing water preferentially to effect dehumidification of the discharged wet gas to a low humidity drying gas having a dew point of -75.degree. to 0.degree. C., (c) recycling the so regenerated low humidity gas having a dew point of -75.degree. to 0.degree. C. to the step (a) and using the regenerated gas for drying again, and (d) regenerating the adsorbing bed in which water has been adsorbed, whereby the food is dried to the substantially absolutely dry state.

Abstract: A liquid food, a medicine or a natural food to be dried is subjected to vacuum evaporation and drying with a dry gas simultaneously or alternately, and by this drying method, the substance is effectively dried without freezing of the substance. A gas containing volatile components, which is discharged from the drying step, is introduced into an absorption layer and is regenerated to a drying gas while the volatile components of the substance, such as aroma, are recovered in the form of a liquid. In this drying method, the drying process is carried out entirely in a closed circuit system.

Abstract: A process for concentrating or liquefying a specified component of a gaseous mixture, characterized by a combination of a step comprising passing a starting gaseous mixture containing a dilute gaseous substance to be selectively separated into one adsorbing layer of an adsorbing device consisting of a pair of adsorbing layers to allow it to adsorb the gaseous substance to be selectively separated, releasing the remainder of the gaseous mixture, and before the amount of the adsorbed gas in the adsorbing layer reaches saturation, switching the passing of the starting gaseous mixture over to the other adsorbing layer; a step comprising maintaining the pressure of the inside of the adsorbing layer which has adsorbed the gaseous substance lower than the pressure of the starting gaseous mixture fed, feeding a part of the gas released from the other adsorbing layer or an inert gas from outside the system to desorb the adsorbed gas, again passing the starting gaseous mixture after the end of desorption, and switching