Abstract: A liquid filtration system for separating contaminants from liquids such as coolants used in maching operations. The invention provides the following: (a) filtration apparatus wherein filtered liquid may be withdrawn at a substantially constant rate from a chamber, although supplied thereto at a variable rate, by means of a level-responsive throttling valve in the line to the vacuum pump; (b) the invention is concerned with filtration apparatus employing parallel endless chains with transverse flights which support and transport a strip of filter material in such a way that the length remains constant (i.e.

Abstract: An improved hydrocyclone clarifier for removing contaminants from a liquid, wherein the contaminants are of higher density than the liquid. The cylindrical body, downwardly directed conical baffle, clean flow outlet at the top, and contaminated liquid return line at the bottom are provided as in prior devices of this type. In addition, an outflow line for contaminated liquid is provided on the side of the cylindrical body, and includes an adjustable orifice and flow rate or pressure sensor. Clogging is evidenced by a drop in flow or pressure and automatically initiates a cycle. Also, timing means is provided to initiate a purge cycle, if none has been performed in response to clogging within a predetermined time period. The improved hydrocyclone clarifier is also disclosed in a recirculating purification system including settling tanks.