Details

Autor(en) / Beteiligte

• Hicks, Douglas C.
• Fearn, Wayne A.
• Pleass, Charles M.
• Staples, David

Titel

Development, testing and the economics of a composite/plastic seawater reverse osmosis pump

Ist Teil von

• Desalination, 1989, Vol.73 (1-3), p.95-109

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

1989

Link zum Volltext

Quelle

Elsevier ScienceDirect Journals Complete

Beschreibungen/Notizen

• Plastics, polymers and composites are increasingly found to be cost effective alternatives to metallic components in a wide range of applications. The reverse osmosis (RO) desalination industry is an example where plastics, because of their inertness in saline waters and the ease with which they can be fabricated, have received wide acceptance for use in low pressure applications. However, polymeric materials have not been used extensively in high pressure RO components other than in the membrane housing. Currently available positive displacement, high pressure, seawater pumps, designed for use in small to mid-sized RO systems, rely on combination of metal alloys such as nickel-aluminum-bronze and stainless steels to economically inhibit corrosion. These positive displacement pumps require a transmission to convert rotary motor input linear pumping motion, and dynamic seals or diaphragms to isolate the transmission oil from the seawater in the pump head. Frequent maintenance, susceptibility to electrolysis, the potential for oil contamination of the membrane and seawater contamination of the transmission oil, make them a major operational expense item and at worst, a risk. Responding to the demand for a noncorrodible, low maintenance seawater RO pump, the authors have designed and tested a line of seawater lubricated, axial piston pumps constructed almost entirely from polymers and composites. the pump, referred to as the DELPUMP 1 1 DELPUMP is a Trademark of ISTI Delaware, Inc. of Lewes, Delaware, USA , utilizes the seawater being pumped to cool and lubricate all bearings and to refill the cylinders. As a result, maitenance requirements and risks of contamination have been eliminated. A further benefit by constructing the pump from predominantly nonmetallic materials and by having no two metallic components in electrical contact is the problem of electrolysis has been eliminated. This paper describes the general design and operating principle behind the pump as well as the economics for its use as a substitute for conventional oil lubricated pumps. A summary of operational data from commercial installation operators and plant assemblers for current commercially available pumps is given. Data is presented from a series of in-house endurance test sequences performed on the DELPUMP line.