Study On The Integrated Utilization Of Wastewater From Avermectins

The wastewater from avermectins production was high concentration organic wastewater, which have mostly rudimental culture medium ,mycelium and metabolize production and a small quality of avermectins. The composition of wastewater was rather complexity and high concentration contamination, the COD achieved 27000～30000mg/L. The rivers which the wastewater poured into directly without any treatment from the avermectins factories were polluted seriously, which had been a hard nut to crack of the healthy development of the industry. In this paper ,the way of comprehensive utilization of the wastewater was studied to make it reclaimed and reduce pollution. Meanwhile, the quality of avermectins wastewater was inspected.The avermectins wastewater was by way of part of ferment culture medium, designed different concentration of avermectins wastewater, which separate fermented Streptomyces avermitilis,S.cacat var.asoensis,Saccharopolyspora spinosa,Bacil-lus thurgiensis and Streptomyces hyroscupicusvar.Jingganggensis yen. The biology mensuration of ferment and compositive benefit were analyzed, and the conditions of fermentation process was optimized. One Streptomyces avermitilis strain A-25# and the other one S.cacat var.asoensis strain S-17# which could grow well and produce mycelium in wastewater had been screened out after domestication and selection. The optimum technological parameters of wastewater pretreatment and fermentation process were found out. The results showed that the wastewater concentration of 40% fermented avermictins strain, the result of biology mensuration was approximately 3186ug/ml. compare with common water, the result enhance 18%. The wastewater concentration of 60% fermented S.cacat var.asoensis strain, the result of biology mensuration was approximately 9250ug/ml. The wastewater was cycled and contamination of wastewater was reduced largely which could lighten the stress of wastewater treatment obviously. By means of comprehensive utilization of avermectins wastewater to produce avermectins and S.cacat var.asoensis, not only the wastewater pollution to environment could be reduced, but also the aim at balancing the cost of the wastewater further treatment and even at gaining economic profit could be achieved. In addition, it was easy for most of averectins factories of small scale to accept because of its simpleness and feasibility. Compared with the traditional method, the new way had many strongpoints and was a tendency of avermectins industry to develop. Both of the technology routes had obvious economic and social benefits.