Difficultly Biodegradable Industrial Wastewater Treatment By Micro Aerobic Hydrolysis Acidificationhybrid Aerobic Process

High-concentrated and difficultly biodegradable with complicated components and bio-toxicity, antibiotic wastewater and dyeing wastewater are the main pollution sources of industrial wastewater in China. These two kinds of wastewater are focus and major problems in China's current study of industrial wastewater control. Hydrolysis acidification and aerobic processes are dominating in industrial wastewater treatment, the form and function efficiency of the processes are still hotspots of industrial wastewater treatment technology study and application.In recent decade, our research team has studied systematically and profoundly on hydrolysis acidification and aerobic technology of difficultly biodegradable industrial wastewater treatment, and has developed some news high-concentrated and difficultly biodegradable wastewater treatment technology such as hybrid hydrolysis acidification reactor, hybrid aerobic bio-reactor and micro-aerobic hydrolysis acidification reactor. These examinations and news technology application strengthen the efficiency of hydrolysis acidification and aerobic processes, and extend the application of the processes.On the base of these examination and study in recent years, a new treatment process of micro-aerobic hydrolysis acidification—hybrid aerobic technology was established. Based on the research achievements of small-scale and middle-scale experiments, this paper applied the technology to large-scale difficultly biodegradable industrial wastewater treatment, and studied did the productive research. The effect and efficiency of micro-aerobic hydrolysis acidification—hybrid aerobic system treatment antibiotic wastewater and dyeing wastewater, and the process and mechanism of the system high-efficiency treatment difficultly biodegradable wastewater were studied. In the paper , start-up of bio-treatment system, efficiency of long-time system circulate, a contrast to other processes, and control and mechanism of sludge bulking were all studied.In the end of the paper, advanced treating of dyeing wastewater effluent of micro-aerobic hydrolysis acidification—hybrid aerobic system were studied. With the study based on large-scale industrial wastewater treatment projects, the results of the research have important indicative function in promoting application of hydrolysis acidification and aerobic processes, as well as the difficultly biodegradable industrial wastewater treatment.The research shows that the pretreatment of high concentration wastewater by micro-aerobic hydrolysis acidification reactor is effective, thus greatly improving the biodegradability of wastewater. As the reduce of organics is not the target of micro-aerobic hydrolysis acidification reactor, aciditication degree, BOD5/COD and variation of SCOD were adopted to estimate the hydrolysis acidification function of difficultly biodegradable wastewater treatment by micro-aerobic hydrolysis acidification reactor, which is exact and exercisable in estimating the efficiency of the reactor application in practicality projects. For both high-concentrated antibiotic wastewater treating and difficultly biodegradable dyeing wastewater treating, micro-aerobic hydrolysis acidification reactor exhibited an excellent pretreatment function, and it's helpful for subsequent aerobic treatment.Hybrid aerobic bio-reactor process is a new and efficient aerobic treating process. The process exhibited characteristics of being efficient and stable in antibiotic wastewater treatment. The long-time circulation proved that the hybrid aerobic bio-reactor process is more efficient than the traditional activated sludge processes; and that the removal effect of wastewater organics of micro-aerobic hydrolysis acidification—hybrid aerobic bio-reactor process could reach to 89.1%. In a contrast of parallel running to batch-flow CASS technology, hybrid aerobic bio-reactor showed its all-around advantages, which is more suitable for high-concentrated and difficultly biodegradable wastewater treatment. Meanwhile, used hybrid aerobic bio-reactor has a good treating effect on difficultly biodegradable dyeing wastewater treatment. In the paper, dynamic model of hybrid aerobic bio-reactor for difficultly biodegradable wastewater treatment was proposed.There generally exists high concentration SO42- in industrial wastewater. High-sulfide sludge bulking usually takes place in aerobic wastewater treatment. Based on the characteristics of high-sulfide sludge bulking occurring in practicality project, a new theory of the mechanism of high-sulfide sludge bulking was gained. According the causes of high-sulfide sludge bulking, a method of"DO-pH"was brought to control high-sulfide sludge bulking. The results demonstrated that the method is simple and effective, suitable for high-sulfide sludge bulking in aerobic wastewater treatment.Advanced treatment and recycling application of dyeing wastewater was studied based on good treating effect of micro-aerobic hydrolysis acidification—hybrid aerobic system treatment for dyeing wastewater. An advanced treatment process of"two-stage coagulation—clarification—filtration—softening"was put forward. In the treating process, a new advanced treatment concept of core of water quality, clear-waster combined treatment and divided recycling was also put forward. The results of test and running shows that the investment and running of dyeing wastewater advanced treatment system is economic, with the reusing rate of advanced-treated wastewater up to 66.7%, and the project investment can be recovered within one and a half years.