Experimental Research On Two-stage Anaerobic Treatment Of Traditional Chinese Medicine Pharmaceutical

In recent years, troditional Chinese medicine enterprises developed rapidly,thereupon the increase in production of traditional Chinese medicine also led to a sharp increase of production wastewater, with the resulting problem of water pollution increasingly severe. Due to the variety of traditional Chinese wastewater has complex composition, high concentrations of pollutants, and containing certain hazardous substances, so the treatment method for Chinese traditional medicine wastewater has not yet formed a relatively mature technology. In this paper, we study on the two-stage anaerobic treatment of traditional Chinese medicine wastewater, use the UASB as single reactor, based on the theory of SMPA. This paper discusses the factors that influence the process and the treatment effect, and discusses the characteristics of granular sludge at all stages within the reactor when the process running, providing optimum parameters of support in practical engineering applications.The study researched on Chinese traditional medicine wastewater of an enterprise in the Zhengzhou as the target. The wastewater of this company showed acidic pH because it easily acidification.With a strong sour smell, the wastewater has high concentration of organic matter, complex types, high SS and chroma.This paper studied the two-stage anaerobic treatment of traditional Chinese medicine wastewater. The results showed that, under conditions that VLR = 24.87 kgCOD/ m3·d, HRT=10 h, COD removal rate of reactor1 reached 85.3%, COD removal rate of reactor2 was 49.02%. Removal of two-stage anaerobic systems reached 92.51%. Two-stage anaerobic systems have good removal of volatile acids, VFA concentrations of reactor1 effluent below 3 mmol/L, VFA concentrations of reactor2 effluent below 2 mmol/L.pH of reactor1 effluent between 6.65 and 8.21, pH of reactor1 effluent between 7.12 and 8.48. When the volume load to 25.13 kgCOD/m3·d, daily gas production of reactor1 reached the highest 53.3 L/d, reactor2 gas production is lower, up to 7.8 L/d.The removal rate of two-stage anaerobic treatment can be further increased by 4% than single stage anaerobic process, the effluent COD of two-stage anaerobic treatment can be reduced more than 40% than single stage anaerobic process.We obtain the following results by research the influence of temperature, HRT, VLR and other environmental factors on the efficiency of two-stage anaerobic treatment system. Used the two-stage anaerobic treatment in traditional Chinese medicine wastewater, when HRT in the range of 20.8-32 h,volume loading in the range of 5.35~12.35 kgCOD/m3·d, COD removal rate can reach more than 92%. The suitbale HRT is between 20.8-32 h, the best upflow velocity determined by the concentration of organic matter in the wastewater. For example, the best upflow velocity of reactor1 is 3.5 m/h when influent COD is 10000 mg/L, this time reactor1 COD removal rate of 84.99%.Studies on granular sludge characteristics of each anaerobic reactor showed that properties of granular sludge within reactor1 are better than that within reactor2 in all respects.