Efficient Powder Immobilized Bacteria And Its Application In The Treatment Of Coking Wastewater Study

The preparation of immobilized high-efficiency bacteria by growth of the cells on powder materials has been studied in this article. Three aspects have been mainly investigated: the cultivation and acclimation of high-efficiency bacteria, the best ratio of the mixed materials and the properties of coking wastewater degradation by the immobilized high-efficiency bacteria.Three kinds of bacteria preserved in the laboratory have been adopted, and have good capability of pollutants degradation. The best mix ratio is 3∶1∶3. The optimum culture conditions have been found: 25～30℃, additional amount of bacteria is 2mL, table speed is 125r/min around. The original water quality are COD 2480 mg·L^-1, phenol 38.71 mg·L^-1, NH₃-N 88.78mg·L^-1, and the degradation rate by high-efficiency bacteria treated 3 days are 74.07%, 83.49%, 65.05% respectively.Through the comparison of quantity of cells absorbed on the eight kinds of materials, activated carbon, zeolite, sawdust and middlings have been chosen to use as materials of immobilized high-efficiency bacteria. According to the quantity of cells absorbed on unit mass of mixed materials, the best ratio of the four materials are 25.00%, 25.00%, 37.50% and 12.50% respectively. The optimum culture conditions of high-efficiency bacteria growing on the mixed materials have been found: 30℃, additional amount of bacteria is 2mL and table speed is 120r/min around.Under the condition of same running time, the degradation rate on coking wastewater by immobilized high-efficiency bacteria is significantly higher than by free cells. The best degradation conditions of them have been found: additional amount is 4g, pH 7～8, 30℃and table Speed is 125r/min. The original water quality are COD 2410 mg·L^-1, phenol 38.20 mg·L^-1, NH₃-N 87.50mg·L^-1, and the degradation rate by immobilized high-efficiency bacteria treated 3 days are 83.14%, 88.47%, 70.52% respectively.The performance of immobilized high-efficiency bacteria have been studied under conditions of different ways of preservation, different time of preservation. And the availability of extensive cultivation has also been investigated.