Patent ID: 7270755

Claim:
The method of filtering contaminated particulates from a process liquid having a predetermined specific gravity to enable re-use of the filtered and de-contaminated process liquid, comprising: a) drawing particulate contaminated process liquid from a source thereof; b) applying pressure of from approximately 20 to 150 psi to the particulate contaminated process liquid drawn from said source; c) delivering an initial quantity of said pressurized particulate contaminated process liquid into a filter chamber having an inlet port, an outlet port and a composite filter bed formed by distinct super-buoyant filter particles having a specific gravity lower than one half that of the said predetermined specific gravity of said process liquid and have a particle size of 0.1 microns to 1.0 mm, whereby said filter bed has the capacity to float on top of said process liquid, wherein said super-buoyant particles are restrained by a bed support adapted to resist the process fluid pressure required to move said process liquid through said filter bed at said pressure; d) continuing the delivery of said pressurized particulate contaminated process liquid into the inlet port of said filter chamber to effect displacement of a composite mass of distinct filter particles comprising said filter bed from adjacent said inlet port to adjacent said outlet port where displacement of said filter bed is terminated; e) continuing the delivery of said pressurized particulate contaminated process liquid into said filter chamber after displacement of said filter bed has terminated, whereby continued delivery of said pressurized process liquid into said filter chamber results in said process liquid being forced to flow through the now stationary composite mass of distinct super-buoyant filter particles whereby said particulates are captured and retained by said composite mass of distinct filter particles; f) discharging filtered and de-contaminated process liquid from said filter chamber through said outlet port and delivery to at least one storage reservoir; and g) backwashing said filter bed to remove contaminants from said super-buoyant particles.