Industrial Practice To Treat Chemical Wastewater By The Hydrolysis +A/O Process

This subject was about study of pilot test and industrial practice, for applyingthe hydrolysis(acidification)+A/O new process combination to treat chemicalwastewater of Lanzhou petro-chemical company. With the cooperation betweenBeijing Huanlike company and Lanzhou petro-chemical company, we used thehydrolysis(acidification)+A/O process and conducted some industrial tests inwastewater treatment plant of Lanzhou petro-chemical company ,based on these tests,we had reformed and begun to run 5.5×104t/d industrial treatment installation. Thissubject had successfully treated highly concentrated refractory mixed chemicalwastewater. So we would like to consider this subject creative, applicable andvaluable for promotion.The chemical wastewater was a complex system, which component parts werepoisonous and the amount of every part changed rapidly. The experimental resultsshowed that synthetic pollution-control should be used in order to deal with severaldifferent kind of the chemical wastewater. We depend much on site tests andadjustments to determine the operation condition of the treatment environment.During the 3-month industrial treatment test in the company, the relations amongoperation indexes as pH, temperature, dissolved oxygen, degree of alkali etc andtreatment effect were being studied. Also we tested cases of excessive treatmentvolume and wastewater and all these tests had satisfying results.The industrial installation used the hydrolysis(acidification)+A/O process. Aftertreating chemical wastewater by hydrolysis(acidification), BOD5/CODCr ofwastewater had rising tread, BOD5/CODCr of wastewater was from 0.2 to 0.37,andthe results indicated that the hydrolysis(acidification) processing raise biochemistryperformance of mixed chemical wastewater. The A/O biological denitrification was akind of new and rising technology in the field of modern biological engineering.Optimization of processing could make its whole treatment system more efficient byadding suspended carriers to A/O biological treatment process. Compared with theactivated sludge method, it was more efficient, stable and controllable. After havingtreated the chemical wastewater by facultative-aerobicmicrobe, the CODCr removalrate was about 85% and NH3-N removal rate is about 85%.Pilot test and industrial practice of the hydrolysis(acidification)+A/O newprocess combination was introduced for treatment of highly concentrated refractorymixed chemical wastewater. The test results showed that it had high pollutant removalratio and a strong resistance to rush loading. The output water had reached to theGB8978-96 Grade 1 standard.The subject had researched and developed a suit of economical and effectivetechnology for treating the chemical wastewater, not only bringed the importantsignificance to contaminated treatment for Lanzhou region, but also played a modelrole for whole chemical system. Therefore, it had extensive application prospect.