| Through experiment, UASB+SBR combined process was employed at ambient temperatures to treat the methylamine and methanol wastewater from a chemical plant in Fei City of Shandong. Considering the practicality, experiment conditions were consistent with that in application. The performances of the UASB, SBR reactors and the whole process were studied through changing the influence factors including the concentration of substrates, hydraulic loading rate, hydraulic retention time, etc. Moreover, the kinetics of system and the feasibility in practice was analyzed and discussed. The main conclusions of experiment and analysis were as follows:(1) UASB reactor finished start-up after 81 days, and the optimal hydraulic retention time was 24h. The biogas production showed a certain relativity with the temperature during steady operation stage.(2) The UASB+SBR could purify the methylamine and methanol wastewater from the chemical plant to some degree, and average COD removal rate was 68.14%.(3) The process displayed a stable removal of TN. The average removal rate of TN can be up to 72.3%, and the TN concentration in SBR effluent was below 16.56mg/L.(4) The whole system had a certain but not strong capability of resisting sudden load change.(5) The process had a capability of resisting the low temperature. When the system run at a low temperature, the biogas production and COD removal rate in UASB reactor went down, but acidification did not occur. The performance of SBR was not influenced greatly by low temperature.(6) Analyzing the kinetics of the process, the degradation of substrates of the whole system inclined to zero grade reaction and k' ,the constant of specific degradation rate for substrates was 0.0293. Concentration and removal rate of substrates, in the system can be calculated by the formula:0.0293t - 0.0626. Analyzing and discussing the feasibility of the process from two hands of both in technique and economy, the process can be viable in practice. |
PDF Full Text Request