Study of Reverse Osmosis for Treating Oil-Shale in-Situ Wastewaters. Final Report

摘要

The results of a study to determine the feasibility of using reverse osmosis for the treatment of the three major wastewater streams evolved during modified in-situ oil shale processing: gas condensate, retort water and excess mine drainage water, are presented in this report. Data was obtained from laboratory tests on real wastewaters treated with composite reverse osmosis membranes. It was found that reverse osmosis can be used to treat retort waters to a quality suitable for reuse within the plant while it can be used to treat excess mine drainage waters for discharge to a receiving stream. Furthermore, although reverse osmosis is also a feasible process for the treatment of gas condensate, a better treatment appears to be steam stripping which alone can produce a water of a quality suitable for plant reuse. The annual operating costs of treating mine drainage waters range from $2.00 to $2.30 per 1000 gallons of permeate while the costs of treating retort waters range from $2.70 to $2.90 per 1000 gallons of permeate, exclusive of the costs of concentrate disposal. The major uncertainty in the use of reverse osmosis for treating oil shale wastewaters is membrane lifetime. Recommendations are made for a field test program to determine the long term susceptibility of composite membranes to fouling and/or degradation. (ERA citation 08:004214)