Study on the culture and degradation characteristics of dominant phenol-degrading bacterium for coal chemical wastewater

To culture dominant phenol-degrading bacterium for bioaugmentation treatment of coal chemical wastewater, 3 phenol-degrading bacterium such as PDB-1, PDB-2 and PDB-3 were enriched and screened from activated sludge in the coal gasification wastewater treatment plant. The culture conditions such as temperature, pH and additional carbon source were analyzed. At last, the degradation effects of raw water were investigated. Results indicated that PDB-2 was the best bacterial strain with the strongest phenol-degrading ability. The degradation rate was 96.6% in 24 h under the initial phenol concentration of 400mg/L. The degradation rates were respectively 89.5% and 96.1% in 24 h and 36h under the initial phenol concentration of 800mg/L. Under the initial phenol concentration of 400mg/L, the dominant phenol-degrading bacterium grew best with the temperature of 30 degrees C and pH of 7 similar to 7.5, and 100mg/L or 200mg/L addition of glucose could further increase the 24 h degradation rate. When the preprocessed coal gasification wastewater was used to acclimate PDB-2, the total phenol and COD concentration of raw water were 18.2 mg/L and 193 mg/L with the corresponding 48h degradation rate of 95.8% and 92.5%.