Abstract: The invention relates to an improved separation device in which a plate unit containing the filter comprises a separate abutment ring and a cassette which can be easily connected thereto, said cassette comprising at least one filter together with, if required, a frame belonging thereto so as to support the filter. If the filter consists of a flexible membrane, this is fitted into a special frame. However, if the filter is a rigid self-supporting filter of a porous material, for example, a ceramic filter or the like, a separate frame is not needed to support the filter.

Abstract: The invention concerns a method and a device for separation of separable constituents from a liquid medium. The separation device comprises only one cell or a stack of a plurality of adjacent cell, whereby each cell consists of a plate unit containing a filter, an inlet for supplying the liquid medium into a chamber, and outlet for discharging the reject and an outlet for discharging the permeate. The liquid medium is subjected to a strong turbulence created by a convenient designed rotor, possible combined with sound waves, whereby the deposition of separable constituents on the filter is prevented or essentially reduced.

Abstract: Water is recovered from sludge, such as from sewage treatment plants, or wood processing or food processing industries, by either electrically ionizing the sludge or treating the sludge with ultrasound, and then adding coagulant to the sludge to effect coagulation. Prior to or substantially simultaneously with coagulation, the sludge is vigorously mixed, and then the sludge is flocculated and water is mechanically removed from the flocculated sludge. Water removal can be optimized by adding news print pulp, or a tenside, to the sludge just prior to mechanical removal. Free water may also be removed by filtering just prior to mechanical removal, and mechanical removal can take place in two consecutive stages, first a low pressure (1-5 bar) stage to produce a cake, and then the cake is broken up and subjected to a high pressure (5-60 bar) stage.

Abstract: Waste plastic material is treated so as to make possible its utilization as a binder component in road surfacing materials, as a fuel, or for other desirable purposes. The waste plastic material is made at least partially fluid by mixing it with a solvent. The solvent is waste fats produced in refining or by treating animal and/or vegetable fats, crude fatty acids obtained as byproducts of refining fats, or fatty acids or pitch obtained by distilling hydrolyzed fats. The solvent is typically mixed with waste plastic material in the ratio of less than 1:2, preferably about 1:3, and at a temperature of between about 150.degree.-250.degree. C.