Evaluation of effects of phenol recovery on biooxidation and tertiary treatment of SRC-I wastewater. Final technical report

• Main Authors: Mitchell, J.W., Watt, J.C., Cowan, W.F., Schuyler, S.E.
• Language: unknown
• Published: 2013
• Subjects: 01 COAL; LIGNITE; AND PEAT; BIOREACTORS; OPERATION; SRC PROCESS; WASTE WATER; CHEMICAL COMPOSITION; DEPHENOLIZATION; WATER TREATMENT; ACTIVATED CARBON; AMMONIA; BIOCHEMICAL OXYGEN DEMAND; BORON; CALCIUM; CHEMICAL OXYGEN DEMAND; CHLORIDES; COAL LIQUEFACTION; CYANIDES; DEMONSTRATION PLANTS; EXPERIMENTAL DATA; FLUORIDES; GAS CHROMATOGRAPHY; IRON; MAGNESIUM; MASS SPECTROSCOPY; NITRATES; NITRITES; OXIDATION; PESTICIDES; PHENOL; PHENOLS; PHOSPHATES; RECOVERY; SODIUM; SULFATES; SULFIDES; THIOCYANATES; VOLATILE MATTER; ADSORBENTS; ALKALI METALS; ALKALINE EARTH METALS; ANTITHYROID DRUGS; AROMATICS; CARBON; CARBONIC ACID DERIVATIVES; CHALCOGENIDES; CHEMICAL REACTIONS; CHLORINE COMPOUNDS; CHROMATOGRAPHY; Carbonic acid
• Online Access: http://www.osti.gov/servlets/purl/6868808; https://www.osti.gov/biblio/6868808; https://doi.org/10.2172/6868808

Addition of phenol recovery to the wastewater treatment scheme in the Baseline Design for the SRC-I Demonstration Plant was evaluated as a major post-Baseline effort. Phenol recovery affects many downstream processes, but this study was designed to assess primarily its effects on biooxidation and subsequent tertiary treatment. Two parallel treatment schemes were set up, one to treat dephenolated wastewaters and the other for processed nondephenolated wastewaters, a simulation of the Baseline Design. The study focused on comparisons of five areas: effluent quality; system stability; the need for continuous, high-dose powdered activated carbon (PAC) augmentation to the bioreactor; minimum bioreactor hydraulic residence time (HRT); and tertiary treatment requirements. The results show that phenol recovery improves the quality of the bioreactor effluent in terms of residual organics and color. With phenol recovery, PAC augmentation is not required; without phenol recovery, PAC is needed to produce a comparable effluent. Dephenolization also enhances the stability of biooxidation, and reduces the minimum HRT required. With tertiary treatment, both schemes can meet the effluent concentrations published in the SRC-I Final Envivornmental Impact Statement, as well as the anticipated effluent limits. However, phenol recovery does provide a wider safety margin and could eliminate the need for some of the tertiary treatment steps. Based solely on the technical merits observed in this study, phenol recovery is recommended. The final selection should, however, also consider economic tradeoffs and results of other studies such as toxicology testing of the effluents. 34 references, 30 figures and 26 tables.