Study On Emulsion Wastewater Of Mechanical Processing Industry

The paper studied the treatment of emulsion wastewater generated from mechanical machining process, in the bearing manufacturing enterprise’s wastewater treatment project. According to the actual wastewater qualities, the current emission standards and the existing treatment methods, this study executed the following works and realized an effective process for the treatment.(1)Both the advantages and disadvantages of the existing references about waste emulsion waste water treatments were summarized. Co-coagulation process was adopted for the primary treatment based on the influent qualities and the effluent standards.(2) Coagulant experiments were carried out to investigate the effects of dosage, pH, and procedure on the wastewater treatment process with PAC as coagulant and PAM as Co-coagulant. The optimal dosage of PAC was3000mg/L followed by a adding dosage of PAM of1.5mg/L under a pH of8.0were selected.(3) According to the coagulant experiment results, an integrated emulsion wastewater treatment system was designed, which consisted of oil collection, co-coagulation, suspended carbon biological absorption and bio-contact oxidation units.(4) The effluent was measured and assessed after final acceptation and the COD, SS and OIL44.7mg/L,3.42mg/L and2.4mg/L were obtained respectively, which were much lower than that of the standard requirements in the Integrated Wastewater Discharge Standard (GB8978-1996). Finally, the effluent was permitted to discharge into the municipal sewage pipe network.The process and units in this study can be applied to wider cases, and can be used as references for other wastewater treatment of mechanical machining industries.