Research On The Technology Of Dealing With The Fiberboard Production Wastewater Of Fast-Growing Eucalyptus

The main subject of the article was committed to a simulating lab test about the Height (Medium) density fiberboard(H(M)DF) of fast-growing eucalyptus class) wastewater’s treatment with the process of coagulation and sedimentation+UASB+Biological contact oxidation+flocculation flotation, Using field testing, theoretical analysis and engineering practice at the same time to determine the best combination of technology and process parameters of wastewater treatment, taking Guangxi wood industry company wastewater treatment as an example of engineering application and achieved the expected result.(1) The experiment and engineering practice showed that the process of coagulation and sedimentation+UASB+Biological contact oxidation+flocculation flotation was feasible to deal with the M(H)DF wastewater. When the process parameters controlled properly,(the effluent quality can achieve the I level of the "Integrated Wastewater Discharge Standard "(GB8978-1996).(2) It was proved that when the dosage of PAC and PAM was600mg/L and100mg/L respectively, with regard to hot-grinding wastewater concentration of COD was16250mg/L, the removal rate was reached at65%.(3) The experiment was confirmed the biological treatment phase of the process parameters. The removal of COD could reach67%, when the VLR was6.825kgCOD/m3·d. The removal of COD could reach89.8%, when the volumetric load of biological contact oxidation treatment was0.474kg BOD5/m3·d and the HRT was24h.(4) The experiment showed that the flocculation flotation method was better than the biological activated carbon method in the depth treatment. Based on the experience, the reason was that the residual COD’s main ingredient was poorly biodegradable material after the process of UASB+Biological contact oxidation. It was hard to reach the adsorption and degradation equilibrium.(5) The engineering design was conservatism by using the lower load than the experiment to reach the stable and qualified effluent water. In the design of building project, the mixed waste regulation pool, contact oxidation tank, secondary sedimentation tank,2#intermediate pond and rainwater regulation pool combined into a combination pool, sharing the wall,to save a lot of floor area and project investment.(6) After engineering debugging, the effluent water was better than expected. The water of secondary sedimentation tank was able to feed the landscape goldfish, which was highly praised. Acceptance by the environmental protection authorities monitoring showed that the average COD of the effluent water was about36mg/L, BOD5about2.6mg/L, the rest of the indicators were far below the I level of the "Integrated Pollutant Discharge Standard "(GB8978-1996).(7) This project can be used as a demonstration project of M(H)DF wastewater treatment in fast-growing eucalyptus and pine-based fiberboard production in southern China.