The Experimental Study Of Removal Organic Compounds From Nanofiltration Enrichment Water

This subject was supported by urban wastewater reuse and water security technology of research and demonstration, leading under the major science and technology projects of national water pollution control and management (2008 ZX07314-003).The Nanofiltration enrichment water produced by using desalination technology was the test water.The influent is high levels of salt, low COD load, high nitrogen, low ammonia and low turbidity. The experiment chose SBR and Biological contact oxidation process to be used separately to wipe off the organic matter from nanofiltration enrichment water, by means of consulting lots of literature. The research was as follows:The SBR reactor was used to cultivate activated sludge which could be quickly acclimated by increasing gradually salinity of influent and adding moderately glucose. At steady state, SVI was about 55~57ml/g, the effluent of CODcr was 50~55mg/L, about 58% removal, and the effluent of TN was 10~15mg/L, and the removal rate was about 70%. Most of the organics were removed in aerobic phase, while the total nitrogen removal occured mainly in the anoxic phase.In order to find a better operating condition, the main factors of SBR and Biological contact oxidation were studied. (1) When the temperature was 30~35℃, the sludge concentration was 3500 mg / L, pH was 7.6~7.9, the optimum condition of SBR system is hypoxia time of 3 h , aeration time of 4 h, settling time of 1h, then the removal rates of COD and TN were 54.8% and 72.2%, the effluent turbidity was 1.85 NTU. (2)The optimum condition of bio-contact oxidation process was hydraulic retention time of 8h, gas-water ratio of 2:1, temperature of 20~25℃, filler particle(volcanic) size of 15~20 mm conditions, and the removal rates of COD and TN were 65% and 70%, the effluent turbidity was 1.57 NTU.The economic and technical advantages of two processes was simulated and analyzed by from investment and operation costs of engineering. When the influent was aunified quality and quantity, while the effluent was also aunified, SBR was more advantages.