RAIL TRANSPORTATION INDUSTRY WASHWATERS TREATMENT, RECOVERY AND RECYCLE USING ULTRAFILTRATION MEMBRANE

The treatment, recovery, and recycle of internal and external rail car and engine maintenance cleaning solutions through membrane technology is a well established application with several advantages: fresh water usage is decreased significantly; maintenance, waste hauling, heat energy, and chemical usage costs are reduced; waste is recovered as essentially fresh cleaner; and cleaning consistency is improved. Designed as either a point source or end-of-pipe waste treatment method, membrane technology will decrease, and often eliminate, loading and costs on downstream POTW's and other effluent treatment processes.The ultrafilter (UF) operates as a kidney. As rail cars and parts are cleaned, spent cleaning solutions with dirt and oil are fed to the UF membrane system where colloidal and suspended solids, greases, and other contaminants are separated out. Membrane filtrate (permeate) contains excess and dissolved cleaner chemicals and is returned to the cleaning process. This relatively tough duty application calls for the use of membranes designed to optimize performance in terms of cost, ease of use, cleanability, energy efficiency, and maximum solids concentrate.This paper surveys the performance of membrane systems operating on wastewaters at rail transportation industry sites. Productivity, filtrate quality, and operating costs on a number of installations show that membrane filtration is an economically viable and accepted technology for this industry.