一、Product Introduction
AOA low-consumption and high-efficiency water purifier adopts the AOA technology of Peng Yongzhen, academician of the Chinese Academy of Engineering, a distinguished expert of Guangxi Biqingyuan Environmental Protection Investment Co., Ltd., which is a new type of low-consumption and high-efficiency process, with the characteristics of "LEC": low energy consumption (Low Energy) / high efficiency (Efficiency) / traditional non-membrane process (Conventional). The full name of this technology is continuous flow anaerobic/aerobic/anoxic sludge double reflux process, which is the world's first and internationally leading, and was first applied to the second phase of the Cenxi Sewage Treatment Plant project (30,000t/d) by Biqingyuan, and the technology won the first prize of the 2020 Guangxi Science and Technology Progress Award.
The AOA low-consumption and high-efficiency water purifier produced based on this technology further reduces the operating energy consumption, strengthens the biological specific space, optimizes the separation of slurry and water, and deeply denitrizes and removes phosphorus, overcoming the shortcomings of insufficient carbon source, poor sludge sedimentation effect and unstable water quality in the traditional process. The equipment occupies a smaller area, has higher effluent stability, lower investment and operating costs, and can meet China's more stringent effluent discharge standards in the future, which can effectively carry out advanced treatment of sewage and realize resource utilization, and is suitable for decentralized sewage treatment fields such as villages and towns, communities, hospitals, shopping malls, service areas, fisheries, and aquaculture.
二、Process
In the AOA low-consumption and high-efficiency water purifier, the sewage first enters the anaerobic zone, and the sludge in the anaerobic zone converts the external carbon source into an intracellular carbon source to achieve the purpose of COD removal, and the phosphorus bacteria complete the phosphorus release reaction. Subsequently, the sewage enters the aerobic zone, and the polyphosphate bacteria complete the excessive phosphorus absorption to achieve the purpose of phosphorus removal under aerobic conditions, and the nitrifying bacteria complete the nitrification reaction. Finally, the sludge enters the anoxic zone and uses the carbon source previously stored in the anaerobic zone to remove the nitrate nitrogen in the mixed solution to complete the denitrification effect. The sludge is returned to the anaerobic zone to provide sludge for the biochemical tank, and the other sludge is returned to the anoxic zone, where the internal carbon source contained in the reflux sludge is enhanced for denitrification and deep denitrification. The process accomplishes phosphorus removal by discharging a certain amount of sludge at the end of the aerobic zone. At the same time, the equipment is filled with high-efficiency PPC new filler to strengthen the treatment effect and reduce sludge production.
三、Technical advantages:
(1) Save drug consumption. In the traditional post-denitrification process, the organic carbon source in the wastewater is mainly removed by aeration in the aerobic section, while in the endogenous denitrification process, the organic carbon source in the raw water is mainly absorbed and utilized by microorganisms in the anaerobic stage and removed. Most of the organic matter is stored as an intracellular carbon source for the subsequent denitrification process. There is no need for additional carbon sources.
(2) Save energy consumption. Compared with traditional pre-denitrification, the effluent from the aerobic zone in the endogenous denitrification process directly enters the anoxic zone for denitrification, saving a lot of energy consumption in the internal circulation. At the same time, because the organic matter is mainly used by microbial storage and subsequent denitrification, the aeration energy consumption required for aerobic removal of organic matter is eliminated.
(3) High denitrification efficiency. As with the traditional post-denitrification process, the post-endogenous denitrification process can theoretically achieve complete nitrogen removal when the carbon source is sufficient. The nitrate or nitrite nitrogen produced in the aerobic stage can be converted to N2 by endogenous denitrification in the anoxic section and removed. Nitrate or nitrite nitrogen in the effluent is reduced, which greatly improves the denitrification efficiency of the process.
(4) The output of residual sludge is less. In the endogenous denitrification process, the carbon source in the wastewater is mainly stored by microorganisms in the anaerobic section for subsequent denitrification. Only some of the organic carbon sources are used by microorganisms for growth and proliferation during the aerobic phase, thus reducing sludge production in the system.
(5) Simple process control. The HRT of this process was 12-16 h, and the reaction time was moderate. Only a second set of sludge reflux is added, i.e. sludge is returned to the anoxic zone, and no additional control is required. The process is simple, the operation is convenient, and it is suitable for practical application in a variety of environments.
