Abstract: A washing apparatus includes a bubbling wash section for impinging bubbles in washing liquid to a material such as a machined work to be washed so as to remove solids such as sludges and oils adhered to the material to be washed, and a sludge removal and oily water separation section for removing sludges or the like mixed with the washing liquid at the bubbling wash section and for separating oily water in the washing liquid, the washing liquid passed through said sludge removal and oily water separation section being returned to the initial bubbling wash section for circulation. An activated carbon filtration section for connection with the bubbling wash section is optionally provided.

Abstract: A device for fining bubbles of gas contained in liquid includes at least two flow channel members confronting each other to form a flow channel therebetween. An inlet and an outlet are provided on one side and the other side of the flow channel members. A recess surface including a first recess and a second recess is formed on at least one of confronting surfaces of the flow channel members. The first recess and the second recess extend from the inlet to the outlet, respectively, and intersect each other at plural positions where the flow of the liquid premixed with gas in the first recess collides with that in the second recess.

Abstract: A washing apparatus includes a bubbling wash section for impinging bubbles in washing liquid to a material such as a machined work to be washed so as to remove solids such as sludges and oils adhered to the material to be washed, and a sludge removal and oily water separation section for removing sludges or the like mixed with the washing liquid at the bubbling wash section and for separating oily water in the washing liquid, the washing liquid passed through said sludge removal and oily water separation section being returned to the initial bubbling wash section for circulation. An activated carbon filtration section for connection with the bubbling wash section is optionally provided.

Abstract: A liquid purifying apparatus comprising; a cylindrical casing having a bottom and a tapered side wall which is formed so that an inner diameter of the cylindrical casing is made larger at an upper portion than a lower portion; a roll filter member inserted in the casing having fastening band arranged to surround the roll filter member and formed cylindrically so that the cylindrical fastening band having a diameter which is substantially equal at every portion along an axis thereof to the inner diameter of the casing at its lower portion; and a tapered gap defined between the casing and the roll filter member so that the gap is enlarged toward its upper portion.

Abstract: An impeller for a rotary fluid machine of the centrifugal type is disclosed which is adapted to be constructed as a liquid pump or gas compressor. The impeller comprises a disc having a boss which is fitted on a drive shaft, and a plurality of blades which are uniformly spaced apart circumferentially and axially project from at least one side of the disc. Each blade has a front and a rear surface, and a fluid path is defined between the front surface of a blade and the rear surface of an adjacent blade. The fluid path is arranged to extend from around the boss to the outer periphery of the disc. The width of the fluid path decreases gradually from around the boss toward the outer periphery of the disc, but the fluid path has a constant depth. The front and the rear surface of each blade are substantially arranged along circular arcs having different radii of curvature which are struck from a common center point.

Abstract: Disclosed is a compost producing apparatus in which materials used for compost such as straws, fallen leaves, dungs, etc., are piled and rotted to produce the compost. In this apparatus, a liquid and air are mixed and agitated together so as to obtain the liquid containing minute air bubbles, and then the liquid is supplied to the materials so as to feed the material with water content as well as oxygen, to thereby promote propagation of organic substances to produce the compost uniformly ripened in a short time.

Abstract: A liquid filter assembly is provided including a roll filter disposed within a casing. A contaminated liquid is supplied to a space adjacent to one end face of the roll filter for passage therethrough. A filter member formed of a material such as non-woven fabric covers the end face of the roll filter where the liquid is supplied, and the filter member is in turn covered by a filter retaining disc so that the filter member is normally urged against the roll filter. The retaining disc is formed with a number of openings to pass the liquid therethrough, thus preventing the liquid pressure from being directly applied to the roll filter.

Abstract: Apparatus for supplying air into a liquid can be used as an aeration apparatus for a biochemical waste water treatment system operating according to an activated sludge process, for example, or as an air bubble generator to be used in a solid particle flotation system. A liquid in a tank is circulated by a pump. An air intake device is disposed in a suction pipe connected to the pump. The air withdrawn by the air intake device is mixed and agitated with the liquid in the pump, whereby minute air bubbles are distributed throughout the liquid. The liquid containing air bubbles is fed from the pump to an injector disposed within the tank, and ejected thereby into the tank in the form of jet water streams.

Abstract: A centrifugal pump includes an impeller and a volute casing. The impeller comprises a main disc and a plurality of vanes which project axially from at least one side of the disc. A fluid passage is formed between each pair of adjacent vanes. The passage has a constant depth and a gradually decreasing width from an inlet to an outlet thereof. Each fluid passage assures a flow of the fluid along the front surface of the associated vane and prevents the occurrence of a vortical flow therein. The volute casing has an inner surface which is substantially U-shaped in section and effectively converts the kinetic energy imparted to the fluid by the impeller into hydraulic pressures.