Vortex of Santee, California (near San Diego, 619-258-9660) operates a CP-4 screw press in an oil filtering recycling process. This came about after a Thomas Register inquiry led to tests in Tampa in 1994.
The raw material at Vortex is used automotive oil filters. These metal canisters contain a paper filter element along with automobile oil and sludge. The patented Vortex Mega Crusher process uses a 200-ton mechanical punch press to pound the filters through an extrusion die at 8,000 psi. This process separates the oil and air, rendering a near solid extrusion that does not drip oil. The solids from the used oil filters go directly to a steel furnace. All the liquids are treated as drain oil and recycled.
In this process about ten filters at a time are crushed in less than one second, generating high hydraulic pressures and velocities. The action, along with some cheese grating of the paper against the die, produces a lot of sludge in the drain waste oil. This mixture is pumped at 5 to 12 gpm into a fine rotating drum screen that is almost horizontal, 30″ in diameter and 4′ long. The paper pulp rolls into a 1-1/2″ to 10″ diameter log in the screen, building fibrous consistency. As the log rotates, it cleans the screen. The log and barrel screen also serve as an accumulator to smooth out the surges in the continuous flow process.
The log end breaks off as it rotates and drops into the Vincent CP-4 screw press hopper. The press liquor is pumped at 1.8 gpm back into the barrel screen with the unfiltered sludge. The cake drops into a continuous flow pusher centrifuge, yielding an additional 0.1 gpm of oil The cake then is blown into an extruded solids hopper. The Vortex machine can produce 45 tons of scrap steel and 3,800 gallons of oil a day from 400 barrels of used oil filters.
The recovered oil is sold to refiners who process it into usable lubricant.
The Vortex oil recovery system is run only periodically. Don Kleine, inventor of the process, points out that they would have to collect all of the used oil filters in California in order to run ten hours a day. Nevertheless, the operation is profitable and the process is available under technical license or machine purchase.
This is a higher horsepower application for a screw press than usual. The press has been upgraded to a 2 hp drive, 15 rpm screw, with 3/4″ long resistor teeth and pie-cut flights.