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Pilot Chemcial Company

Year Submitted: 2011

Process: Filtration

Industry: Chemical Manufacturing

Wastes Reduced: Solid waste

Location: Houston TX

No. of employees: 27

Contact: Russell D. Brown

Phone: 281-448-3222 x30


During product filtration, product was being lost in the filter cake and was not recoverable for recycle. The facility faced two issues, lost product (less yield) and disposal fees. The waste was going to incineration at $730/cubic yard (CUYD). The facility was generating about 13 CUYD per month, costing $9100/mth in incineration disposal costs. The waste contained up to 30% product (up to 7800 lbs valued at $1.80 per pound equaling $14,040). The annual cost of disposal and lost product was about $282,000. Administrative and Engineering Controls were implemented to reduce waste generation by 25% and improve product yields.
(Note: 1 CUYD = ~2000 lbs)

P2 Application:

The product is forced through a pressure leaf filter. A filter media "cake" is formed on the filter leaves. The product is forced through the filter media to remove solids. The filter system was manual. The operator controlled all aspects of filtration including determination of  when the filter was beginning to foul and the cake needed to be changed. The operator would pressure the liquid out of the filter, de-pressure, then open the filter and clean the spent filter media from the filter leaves, collecting it in a 30 CUYD hopper container. Sometimes the filter would not be completely clear of liquids and the filter would be open, losing product to the waste hopper. Additionally, sometimes the spent filter cake would not be properly dried. It would be "wet" with product. Through the use of procedures and process control systems, Pilot Chemical was able to automate the filter and optimize the operation, resulting in a 25% reduction in waste. The automated filter-cleaning system uses pneumatic controls and nitrogen to remove spent filter media. The system now uses time and pressure measurements to control process actions.

  • Total Cost Savings: $187,300.00
  • Comments: Product recoverd for sale totaled = $160,000(88,920 lbs/year).

Details of Reductions

  • 39.0 - Cubic Yard of   Spent Filter Media
Source: TCEQ

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