Technological Development And Application On Bio-Treatment Of High-Concentration Acrylic Acid Wastewater

The "biological" treatment of high concentration acrylic acid and its esters wastewater was put forward in this paper, and the schedual from laboratory to pilot and then to industrialization was identified. Experimental study have shown that anaerobic process as a high concentration acrylic acid and its esters major wastewater treatment is feasible, pilot study determined the technical parameters of acrylic acid and its esters biological wastewater treatment, identified and solved the problems in the operation of the technology. Based on the small scale and the pilot study, the acrylic acid and its esters of acidic wastewater biological treatment plant of 5t/h was established, using the combined technology of UASB and aerobic contact oxidation. The parameters and the operation cost of the industrial plant was determined, which achieved the success of the technology development. The results of the industrialized operation showed:with an influent water CODcr of 2323lmg/L, the effluent CODcr was 713.5mg/L, CODcr removal rate was 96.6%, anaerobic volume load of 2.41kgCOD/m3-d. After secondary treatment, the effluent water meets the discharge standard, with a total cost of 30 yuan/t waste,2 million yuan invested per ton water.This paper develops a new process of UASB and aerobic contact oxidation system, which has the advantages of maintaining the pH balance of the anaerobic system, reducing the usage of alkaline substances, improving the tolerance of microorganisms in high VFA, and improving the adaptability of the microbial strains to acrylic acid. This technology is of significance for the treatment of high concentration organic chemical wastewater which has no alkalinity, high volatile fatty acid, and has the inhibition effect on the growth of microorganism.This project finally achieved the industrialized application of high concentration acrylic acid and its ester wastewater biological treatment, and built up the industrial plant which operates with full load. Compared with other industrial processing methods (such as direct incineration method and catalytic wet oxidation process), its investment per ton water and water cost per ton greatly reduced, possessing significant economic benefits, technical and practical applicability and a wide range of application prospects.