Precision Tube Finishing Inc.

Year Submitted: 2003

Process: Parts Cleaning

Industry: Metal Fabrication

Wastes Reduced: Electrolyte Waste

Substance: Phosphoric/Sulfuric

Equipment: Filtration

Location: Houston TX

No. of employees: 16

Contact: Jim Toney

Phone: (281) 856-7400

Description:

Precision Clean Piping, Inc., electrochemically cleans stainless steel piping components for high-purity applications in the microelectronics, biotechnology, pharmaceutical and health care industries, using a specialized electropolishing process. Tubing diameters typically range from 1/8-inch to 1-inch. The process drives large electric currents through the components by means of a strong, circulating electrolyte (a blend of concentrated phosphoric and sulfuric acids).

P2 Application:

The solution to the problem was to make the electrolyte suitable for other related processes and find other users to whom it could be passed on. The main objections held by potential users of the solution was that it contained sediments and that its iron content was too high. Those problems are mitigated by modifying the electrolyte reservoir, adding a "V" bottom for drainage and a series of baffles to encourage settling of the most egregious solids where they can be drained off and otherwise disposed. A self-cleaning, spiral-wound, stainless steel prefilter is being installed to remove fine particles.

Environmental Benefits:

Approximately 20 tons of solution can be sold for reuse rather than being deep-well injected as a hazardous waste.

Details of Reductions

Additional Information :

Revenue from acid sales is minimal, but avoided disposal and handling costs are well over $30,000 per year. In addition, steps taken to improve purity of used electrolyte in order to win loyalty of potential "reusers" are expected to generate quality improvements in the tubing polishing process itself. Finally, useful life-expectancy of the electrolyte is expected to improve by about 1/3 without reducing its subsequent value to other users.

Source: TCEQ