Abstract: Waste oily water is concentrated by expelling permeate water away from the oil component through ceramic membranes of a cross-flow filter. The filter is in a circulation ring, and is routinely cleaned in situ. The ring has two sight-glass reservoirs between which the cleaning fluid is see-sawed during cleaning cycles, the reverse, oscillating chemical flow being triggered by sight glass float switches. Large annual throughputs are achieved by linking in more processor rings, under control of a single PLC (Programmable Logic Controller), for automated processing. High membrane filter rates are achieved, in the range of 1 to 2 million litres per year per square meter of filter membrane surface area. The system is fail-safe and environmentally friendly.

Abstract: A practicable, compact local system is used to separate emulsified oil from water, enabling re-use or disposal to drain of most of the water. The treated water meets regulatory guidelines for safe disposal to drain. The system can separate highly emulsified oil/water mixes. It uses a ceramic cross-flow membrane filter with pore sizes in the range of 0.005 micron to 1.2 micron, operating at pressures in the range 25 to 150 psi (gauge). Removal of up to about 95% of the water can be achieved. High separation flux rates are achieved by computer controlled cleaning cycles, made practical by providing minimal permeate collection spaces downstream of the filter on the water discharge side. Two independently operable systems may share a modest cabinet.