Solvent extraction process development and on-site trial-plant for phenol removal from industrial coal-gasification wastewater

A phenol removal process was developed for the coal-gasification wastewater. Based on extraction principles and experimental results, an extracting solvent was selected in consideration of phenol removal, solvent recovery and COD removal for the coal-gasification wastewater. The extraction process conditions were studied, and a flowsheet for phenol removal was proposed. An on-site trial-plant of 2 t/h wastewater was set up for testing and industrial verification. The results of the on-site trials showed that more than 93% of the phenols and 80% of COD in the wastewater were removed. The operating cost of the proposed process was approximately balanced by the economic return of the recovered phenols.