Biological Treatment of Wastewaters Produced by Oil Extraction

摘要

The wastewater from Weizhou Terminal Disposal Plant is discharged during the oil extraction process. The quality of the wastewater is as follows: The concentration of Cl~- ranged from 11000 to 12000 mg/L, with an average of 348 mg/L; the value of COD ranged from 150 to 400 mg/L; total sulphur was 21mg/L. It is shown that the COD can't reach the discharge standard of the National Wastewater Discharge Standard of GB8978-1996 (NWDS) with either single anaerobic treatment or aerobic biological treatment, but the effect of the combined treatment processes including the two methods is much better. The quality of outflow is stable and the COD can be kept in the range of 14 mg/L to 67 mg/L, i.e., the outflow water quality can satisfy the first class in NWDS with the combined treatment process.