Pilot-scale Study On Hydrolysis Acidification Combined With MBBR Upgrading Treatment For Traditional Chinese Medicine Wastewater

Chinese medicine industry has developed rapidly in recent years, but the efficiency of treating Chinese medicine wastewater is very low in many existing sewageplant and the treated effluent can not reach the standard stably. With (GB21906-2008) coming into effect, looking for an ecomomic and feasible process to upgrade the treatment of Chinese medicine is helpful for the treated effluent up to the new standard. Furthermore, it also can ensure the sustainable development for Chinese medicine industry.In order to increase the quantity and stabilize the quality of treated wastewater of the Chinese medicine industry's sewageplant, the pilot-scale expriment adopted hydrolysis acidification united with two-staged MBBR process to upgrade the existing one, which included a two-phase anaerobic reactor, an anaerobic contact-reactor and a two-staged contact-oxidation reactor. The effluent of two-phase anaerobic reactor entered hydrolysis acidification reactor firstly in order to improve biodegradability of wastewater and remove some insoluble organics and COD; being a subsequent aerobic process, a two-staged MBBR ensured the efficiency of overall treatment and improved the quality of treated wastewater. This dissertation not only focused on the removal efficiency of COD treated by hydrolysis acidification untied with two-staged MBBR process, but also studied the maximal OLR and OLRr. Meanwhile, it discussed some factors which influence the hydrolysis acidification untied with two-staged MBBR process. Finally, it also compared hydrolysis acidification untied with two-staged MBBR process with the existing one which consists of anaerobic contact-reactor and two-staged contact-oxidation reactor on treating efficiency and management. This thesis aimed at finding out an ecomomic and feasible upgrading process which could make treated effluent reach the stardard.The result of study shows:(1) When CODCr of infow is around 860¹360mg/L, CODCr of effluent treated by upgrading process is 119²06mg/L, the overall COD removal rate ECOD is 85.6% which reach anticipated request and provide good quality of effluent for subsequent decloring flocculation. (2) The maximal value of OLR and OLRr in hydrolysis acidification reactor is 9.29 kg/(m³?d) and 4.6 kg/(m³?d) respectively, with the average 6.75kg/(m³?d) and 3kg/(m³?d) which are 3.5 times and 4 times of the existing anaerobic contact-reactor. The maximal value of OLR and OLRr in primary MBBR are 6.64 kg/(m³Â·d) and 5 kg/(m³Â·d) respectively, with the average 4.66kg/(m³Â·d) and 3 kg/(m³Â·d), which are 4 times and 5 times of the existing primary contact-oxidation reactor. (3) It can improve SV30 through returning aerobic sludge to MBBR. Compared with low SV30 in MBBR, high SV₃₀ in MBBR can improve the removal of COD. (4) After upgrading, the process which has two-phase anaerobic reactor combined with hydrolysis acidification and MBBR is suitable for treating refractory and high-concentration Chinese medicine wastewater, due to its higher OLR, shorter HRT and smaller covering area.The results of this study have significant value for upgrading the existing Chinese medicine wastewater treament station. Meanwhile, they can provide reliable imformation for the later engineering design.