Research And Application Of Microorganisms In The Advanced Decolorization Of Coking Wastewater

The ingredient of coking wastewater is very complex. It mainly contains many kinds of high consistency organic matter that are virulent and difficult to be degraded. At present, the biological methods were wildly used at home and abroad for coking wastewater treating, such as conventional active sludge and method for entirely mixing. The outstanding achievements about biological methods on organic matter treating such as COD, NH3-N, benzene, phenol were got in our country. Nevertheless, the coking wastewater was black and the chrominance of output was so high after currently biological treatment that it is yellow and could not satisfy the country standard for discharging. Therefore, in order to find a highly effective and economical way on treating coking wastewater, a great lot of research was done in the recent years.The main purpose of this subject is to extract the colored matter from the wastewater from secondary sedimentation tanks of coke-plant with macro porous adsorption resin and would be the only carbon source which was utilized to domesticate coking sludge germs,dyeing germs and soil germs. The high efficient degradation germs isolated were enriched and then would be added to the coking wastewater for the degradation of the colored matter. The germs would also be mixed and also be applied in the system to degrade the colored matter in the coking wastewater. The feasibility and degradation characteristic would be estimated through analyzing chrominance and COD of wastewater after experiment.Through the research of microorganisms in the advanced decolorization of coking wastewater, some conclusions had been gotten.1. Some chromophores such as carbonyl compound and ester maybe exist in the colored matter from the IR data.2. The germs, which were domesticated with the colored matter, had strong degradation ability on the wastewater from secondary sedimentation tanks of coke-plant. The removing efficiency of chrominance and COD were about 55% and 60% under the experimental circumstance of 30℃, 72h and 140 rpm, respectively. The chrominance fell from 150-fold to 66.21-fold and the COD fell from 320 mg/L to 128 mg/L. The quality of output water had approached the china Primary Effluent Standard.3. Biodegradation includes sludge adsorption and the decomposition of colored matter. After sludge adsorption, the colored matter absorbed could be oxidized under the aerobic condition and most of the colored matter would be degraded. The decolorization mechanism is in the research. But it is currently considered that the chromophore of the colored matter is decomposed.