Abstract: Apparatus for separating contaminant from water, the contaminant being of lower density than water. The apparatus comprises a settlement chamber, initial separating means, and an entry port for introducing the liquid to be separated into the initial separating means for flow therethrough into the settlement chamber. A contaminant outlet opens from an upper region of the settlement chamber. A pump intake is located towards the lowermost part of the settlement chamber, and feeds a pump. The outlet from the pump is directed to a molecular separation filter capable of separating water from contaminant. Water discharges from the molecular separation filter, and can be further treated by an optional activated carbon filter. Contaminant leaving the molecular separation filter is directed back into the initial separating means.

Abstract: A filter element comprises a relatively rigid fluid-permeable cylinder (5), around which is provided a body (7) of non-woven fibrous filter material. A jacket (6) of permeable material is positioned around the outer surface of the filter material, and is heat-shrunk onto the filter material in order to hold this under substantially uniform radial compression over the whole of its area.

Abstract: A filter assembly (1) comprises a fluid tight housing (6, 7). First and second coupling means (10 and 11) are provided on the housing, each coupling means providing adjacent flow channels into the housing. A filter element is located within the housing, the element having a fluid tight external wall (20) and a filter medium (19) housed within the wall. A first flow path is established between the first and second coupling means through the filter element, while a second flow path between the first and second coupling means is established within the housing but outside the external wall of the filter element.

Abstract: A filter housing comprises a body (1) designed to provide at least one flow path (8) therein. A filter may be secured to the body in operative connection with the flow path. The flow path opens into a substantially planar external face (9) of the body, and behind that external face the body is formed with passages (15a) lying one to each side of the opening, each passage having an internal wedge face facing away from the external face (9) and lying in a plane that makes an acute angle with the plane of the external face. When two such housings are placed with their planar external faces one in contact with the other and with their flow paths in axial alignment, they may be connected together by drawing wedge members (20) into the passages of the respective housings to draw the housings tightly together.

Abstract: A filter pack comprises a first housing member (1) having an inlet port and an outlet port (4) for compressed air; the outlet port being connectable to a piece of equipment, for example a spray gun. A second housing member (6) is removably fitted into the first housing member through an opening (5) therein and has a section (8) protruding from the opening. A retaining ring (12) releasably secures the two housing members together. The second housing member is at least partially filled with activated carbon filter material (18). A wall area (19) of the second housing member is formed with an inlet into the interior thereof, and the wall area combines with part of the first housing member to form a chamber (15) in communication with the inlet and outlet ports. The protruding section (8) of the second housing member has an outlet (9) for connection to an airline, the flow path from the inlet port to the outlet of the second housing member being through the chamber and then through the filter material.

Abstract: Apparatus for removing entrained liquid from a gas stream comprises a cylindrical casing (67) designed to be mounted so that its axis is substantially vertical. An inlet port (62) and a gas outlet port (63) are provided adjacent to the upper end of the casing and drain means (80) are provided at the lower end of the casing whereby separated liquid may be drained therefrom. A gas outlet tube (75) coaxial with the inner surface of the casing, extends downwardly from the upper end thereof, the outlet tube communicating at its upper end with the gas outlet port (63). A plurality of baffles (72) are arranged in an annulus around the outer surface of the outlet tube (75), the baffles being located downstream of the inlet port (62) and shaped to impart a spinning movement to the incoming gas stream. An impingement plate (77) is located downstream of the baffles and has an upper surface extending transversely across the path of the air stream leaving the baffles.

Abstract: A filter element comprises coaxial inner and outer relatively rigid, permeable cylinders (5, 8), each cylinder being circumferentially continuous and sandwiched between the two cylinders, a spirally-wound cylindrical filter structure comprising a plurality of layers of microporous non-woven fibrous material (9), each pair of adjacent layers being separated by a layer of strong, fluid-permeable, flexible support material (10), the filter structure being under substantially uniform radial compression over the whole of its area. The compression is preferably such as to compress the filter structure by from 25% to 45% of its original thickness, and materially increases the efficiency of filters incorporating the structure. A method of effecting the compression during manufacture is also described.

Abstract: Apparatus for treating a supply of compressed air containing carbon monoxide but substantially devoid of free water and of relative humidity sufficient for comfortable breathing, to render it suitable for breathing purposes. The apparatus comprises four sequential filters for preliminary removal of bulk liquids, particulates, carbon dioxide, oil and water aerosols, and hydrocarbon vapors and odors and a pressure vessel (21) having a heater (39) at its inlet to which the air is supplied without any drying treatment. The heater comprises at least one heating element formed of a material which exhibits a rapid increase in electrical resistance at a temperature of from 101.degree. C. to 110.degree. C. From the heater the air passes to and through a bed of granular catalyst material within the pressure vessel, the catalyst oxidising CO in the air to CO.sub.2. A temperature sensor (37) within or immediately downstream of the catalyst bed controls the heater to maintain a mean bed temperature of not less than 100.