ABSTRACT
Synfuels processes, such as the Lurgi dry ash gasification process, produce wastewater with high concentrations of both organic and inorganic contaminants. These contaminants are difficult to remove prior to discharge and create operational problems if recycled back into the process. The research involved the application of coupled fluid bed reactors that combine nitrification and denitrification with organics removal in hydraulically connected anoxic and oxic columns for the treatment of synfuels wastewater from the Great Plains Gasification Plant (GPGP) near Beulah, North Dakota. By-product recovery reduces organic and inorganic concentrations in the wastewater to the point of optimizing economic recovery of the products. The biochemical reactions in the denitrification process are the anaerobic conversion of the nitrate ion to the nitrite ion followed by conversion to nitrogen gas. Suspended growth biological systems such as activated sludge has proven capable of treating the wastewaters removing both organic and inorganic compounds.
