87-11: Reuse of Pretreated Coal Gasification Condensate in a Pilot Scale

The recycle and reuse of waste and process water streams can turn potential environmental problem discharge streams into beneficial cooling tower make-up streams. Three separate 50 days research studies using ammonia and phenol stripped coal gasification condensate from the Great Plains Coal Gasification Plant were performed. The first phase of testing did not use pretreatment for this highly contaminated wastewater. Baseline data indicated severe biological fouling, scaling and corrosion. The second phase, using non-oxidizing biocides and dispersants, was unsuccessful at reducing these problems. The make-up for the third and final phase consisted of biologically treated and filtered water with a dispersant and a phosphorus-based corrosion inhibitor. The pretreatment and corrosion control program used gave excellent results for biological fouling, corrosion and deposition control.