Power Clean® Nutshell Filters

Fine Oil and Suspended Solids Removal

PowerClean® filters are among some of the most advanced nutshell filtration technologies available in the market. With superior design and long filtration runs, PowerClean filters are proven in removing 98% of all suspended solids and insoluble hydrocarbon particles above five microns. 


PowerClean is a simple, automatic system designed to eliminate filter plugging problems without the use of air or gas for particulate removal thanks to a quick media cleaning cycle that generates minimal volumes of backwash wastewater for disposal. Through a rapid fluidization process featuring a powerful shearing action, the contaminants are stripped from the media particles and the filter is quickly returned to service. 


  • Exceptional effluent quality.

  • Short media cleaning cycle interrupts filtration service for only 60 seconds.

  • No need for air scour, stand-by filters, or additional backwash water storage tanks..

  • Optimal protection against oil surge and upset conditions.

  • 100% black walnut media selected for its unmatched durability, oil affinity and coalescing surface properties.

  • High loading capacity and flux rate design (12.5 to 15 gpm/sq.ft.) provides greater throughput and more efficient footprint than other conventional filtration methods.


During the downflow filtration cycle, the raw water passes through the black walnut shell media which effectively removes free oil and suspended solids. Once the maximum differential pressure across the bed has been achieved, the filtration service gives way to the cleaning cycle which consists of five simple steps performed via a computerized sequence: fluidization, discharge, settling, purge, and return to filtration. The media cleanup process, which does not require a separate water source, reverses the flow direction as it is enhanced by a modified centrifugal pump that creates high shear on the media surface.

Next, the slurry of nutshells and water are pumped into an external housing containing a robust wedge-wire assembly for superior scrubbing action. The screen allows the retained oil and particulates to be discharged but prevents the media to pass through as it is recirculated back into the filter vessel through a special nozzle that helps with fluidization and thorough cleaning of the media bed for a duration of 12 minutes in a closed-loop circuit.

Finally, after a quick moment that allows the media to settle, PowerClean is ready to be turned back to filtration mode.


Nutshell filtration is typically installed as a treatment step to reuse oilfield produced water for steam generation or as a polisher before reinjection into a well.

PowerClean is also applied to purify refinery wastewater, steel mill direct spray and caster water, quench water in ethylene cracking plants, copper concentrate decant and cooling water.

Under normal conditions, PowerClean is capable of operating with oil content of up to 50 parts per million (ppm) and can reliably deliver concentrations below 2 ppm.