Abstract: Described is a semipermeable capillary having a tubular semipermeable wall composed of a membrane-forming material (2) and a tubular strengthening layer (1). The tubular strengthening layer includes an elongated tape having mutually overlapped longitudinal edges. The tubular strengthening layer has an open cohesive structure that is embedded in the membrane-forming material whereby the mutually overlapping longitudinal edges are joined together by the membrane-forming material and a continuous phase is formed between the semipermeable wall and the strengthening layer.

Abstract: A device for preparing a spray-dried product is described, the distance between the distribution element and a fluidized bed in the device being such that the particles have essentially reached their critical moisture content. A method showing the mixing of the primary liquid droplets delivered by the distribution element and solid particles is also specified.

Abstract: A device for preparing a spray-dried product includes a drying chamber with a distribution element placed therein for atomizing liquid to be spray-dried, an element for supplying drying gas, an element supplying a stream of solid particles to a stream of droplets atomized from the distribution element, and one or more fluidized beds, each having at least one bottom plate with openings which has gas supply structure opening out at the underside thereof. These fluidized beds are placed connected to each other inside the drying chamber, opposite the distribution element, the above in such a way that the combined streams of droplets from the distribution element and solid particles fall essentially into the first bed, and conveyance of material from the first bed to the second bed can take place.

Abstract: An apparatus is described for treating polluted water. The apparatus comprises a supply system for polluted water; an activated-sludge reactor; one or more filter membrane modules; an air supply system and a discharge system for the treated water. The filter membrane modules comprise hollow membranes within a casing. Said filter membrane modules on one side adjoin the activated-sludge reactor and on the other side adjoin air distribution means. The activated-sludge reactor communicates, via a bypass line, with a sludge receiving container which adjoins the air distribution means. The apparatus functions in such a way that the water to be treated and air supplied are flowing in the same direction through the hollow membranes, the permeate flowing through the membranes towards the space between the casing and the membranes, where it is discharged via permeate discharge system.

Abstract: A membrane for membrane filtration is disclosed, comprising a polymer matrix formed by coagulation with a liquid coagulant from a casting syrup, which polymer matrix is linked to hydrophilic groups belonging to a compound which has a hydrophilic chain section, is not coagulated by the liquid coagulant, is coupled on either side to a hydrophobic chain, is anchored in the polymer matrix by non-chemical bonding, and is composed of a compound which has a molecular weight of at least 2000 and can be used as a thickening agent.

Abstract: Described is a device for obtaining a foam spray-dried product of predetermined bulk density. Thereto a nozzle for spraying a foaming gas comprising liquid is surrounded by a tube for supplying a gas which comprises dry particulate material to the jet of nozzle.Means are present to accurately control the ratio of solids in the liquid to be sprayed and the dry particulate material.The method described that the dry particulate material is made to collide with the jet from the nozzle and that the speed of the gas transporting said dry material is lower than 20 m/sec and preferably from 6 to 12 m/sec.

Abstract: The invention relates to a membrane assembly, provided with a carrier which carries a layer of a macromolecular substance with membrane action, said carrier being a composite carrier comprising on the one side a layer (2) having an open, cohesive structure, whereby layer (6) of the macromolecular substance extends into layer (2), and on the other side a supporting layer (3) on the side turned away from layer (6) having membrane action.The carrier comprises, preferably, completely or partially a knitted or woven textile product. The supporting layer (3) is advantageously a plastic non-woven. The macromolecular substance is expediently a polymer, said substance taking care for the connection of the supporting layer (3) to the remaining parts of the composite carrier.A device for the production of the present membrane assembly is also described.

Abstract: In the cyclic preparation of a length of curds by draining a mixture of whey and curds in an upright column, formed by a permeable casing, the preparation cycle consists of at least three parts: a thickening phase and an extrusion phase from the column and a lateral discharge phase of the length of curds. The mixture is supplied to one end of the casing and a length of the thickened mass of curds is removed periodically at the other end of the casing. The whey/curds column inside the casing is moved forwards at slow speed in the longitudinal direction of the casing during the thickening phase of the preparation cycle, the thickening phase and the extrusion phase taking place at the same time. The discharge phase of the cycle takes place when the column is stationary, within a time span which is less than 20% of the thickening phase and extrusion phase.

Abstract: An apparatus for preparing a curd mass by draining a mixture of whey and curds in an upright column consists of a permeable sleeve or circular or rectangular cross-section, one or more sleeves being surrounded, with some clearance, by a tube monted on a worktable. The apparatus further comprises means at one end of the tube, above or under the worktable, for feeding the mixture of whey and curds and means at the other end of the sleeve, under or above the worktable, for receiving and discharging a drained and extruded curd mass. The free space between the sleeve or sleeves and the tube is subdivided into various compartments, lying one above the other, with the aid of sealing dividers. Each compartment is provided with inlet and outlet connections for whey or cleaning liquid. The sleeve or sleeves disposed inside the same tube forms or form a fixed assembly with the partitions and with said tube.

Abstract: Semipermeable membrane consisting of a polymer, embodying [--SO.sub.3 --] groups; said [--SO.sub.3 --] groups may be present in the continuous polymer chains or may be present in links between continuous polymer chains. The membrane may have been formed either by in situ coagulation of a polymer solution in the pores of a porous substrate or by interfacial crosslinking of a water-soluble phenolic polymer with a sulphonyl halide compound to form an [--SO.sub.3 --] groups embodying polymer in the pores of a substrate.

Abstract: A liquid solution is passed through a multi-stage evaporation plant while using recirculated vapor, fed through a mechanical compressor in order to increase the pressure and temperature of the vapor.The plant comprises a number of evaporators connected in series and split up into a plurality of groups, which comprise a decreasing number of evaporators; as seen in the flow direction--the vapor being fed in parallel, streams through said groups.

Abstract: A scrubber for separating powder particles from a gas stream comprising a closed vertical cylindrical housing having a tangential inlet for the gas stream and a concentric discharge pipe passing through the top of the housing for the removal of the purified gas stream; in which means are provided for flushing the lower portion of the inner wall of the housing. The flushing means comprises an annular gutter surrounding the housing and communicating with said inner wall by means of a large number of narrow passages. The level of the gutter is well above the lower end of the discharge pipe.

Abstract: Method and plant for preparing a non-caking powder by spray-drying a mixture of a concentrate of minimally 48% dry substance, such that in an uninterrupted drying operation the mixture is passed through the so-called sticky-zone, after which a subsequent cooling, rewetting and crystallization is performed, the latter three operations remaining spaced from said sticky-zone.