Quick starting method of efficient autotrophic nitrogen removal system based on MBBR

Abstract

The invention discloses a quick starting method of an efficient autotrophic nitrogen removal system based on an MBBR and belongs to the technical field of biological nitrogen removal for wastewater. The problems are solved that in the prior art, for a related system, the inoculation amount is large, starting time is long, and the nitrogen removal efficiency is low. According to the method, the same segment of denitrification autotrophic nitrogen removal is coupled, a denitrification pond is arranged in front, water outlet backflow of autotrophic nitrogen removal is achieved, nitrate and organic matter are removed at the first stage, and autotrophic nitrogen removal is conducted at the second stage. According to the method, three kinds of operation modes can be achieved and include the parallel operation mode, the dual-series A operation mode and the dual-series B operation mode, and the water outlet directions of four reaction ponds are controlled by communication valves to achieve serial connection or parallel connection or separate operation of the reaction ponds; through means such as inoculation and feeding, an autotrophic nitrogen removal technology is quickly started; according to treatment demands, different technology arrangement modes are achieved. The quick starting method has the advantages that the inoculation proportion is low, staring is conducted quickly, the nitrogen removal efficiency is high, and the tolerance to water inlet organic matter is good.

Description

Technical field [0001] The invention belongs to the technical field of wastewater biological denitrification, and specifically relates to a rapid start method of an MBBR-based high-efficiency autotrophic denitrification system. Background technique [0002] In the 1990s, when the phenomenon of anaerobic ammonia oxidation was discovered, people realized a new type of autotrophic denitrification process. Under anoxic conditions, microorganisms represented by planomycetes directly use nitrite as electron acceptor. Carbon dioxide is the main carbon source, and the biological denitrification process that oxidizes ammonia nitrogen into nitrogen. Because the traditional biological denitrification process often limits the denitrification performance due to the lack of carbon source when treating high ammonia nitrogen and low C / N wastewater, additional organic matter is required. Therefore, the operating cost is increased and the risk of secondary pollution is easily caused. It is not con...

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Problems solved by technology

[0002] In the 1990s, when the phenomenon of anammox was discovered, people realized a new type of autotrophic denitrification process. body, carbon dioxide is the main carbon source, and ammonia nitrogen is oxidized into nitrogen. Because the traditional biological denitrification process often limits the denitrification performance due to the lack of carbon source when dealing with wastewater with high ammonia nitrogen and low C / N, it is necessary to add additional organic matter. , thus increasing the operating cost and easily causing the risk of secondary pollution, which is not conducive to the safe and economical operation of the system. Compared with the traditional nitrification and denitrification process, the autotrophic denitrification process has more advantages. First, the autotrophic denitrification process has more advantages. Anaerobic ammonium oxidation reaction requires partial nitrosation as a pretreatment process. According to its stoichiometric relationship, it can theoretically save 62.5% of feeding power consumption, and it does not need to add additional organic carbon sources, saving 100% of the cost of external carbon sources. In addition, the sludge output is less, which saves the sludge disposal cost. Finally, it can not only reduce the excessive emission of greenhouse gases such as carbon dioxide, but also consume carbon dioxide. However, the theoretical total nitrogen of the autotrophic denitrification process The removal rate is 89%, and it may be difficult to ensure that the effluent reaches the standard for projects with high requirements for effluent total nitrogen

Although the inoculation rate of this technology is low and the startup time is fast, the NH removed by the system in the stable phase 4 + -N and generated NO 3 - The ratio of -N is 8%-15%, which has a certain gap with the chemical ratio (11%). Generally speaking, the system feed water contains a certain amount of BOD 5 It will lead to the occurrence of denitrification phenomenon and cause the ratio to be too small, and the existence of certain nitrite oxidizing bacteria (NOB) in the system will make the ratio too large. It is worth noting that the existence of NOB will compete with AnAOB for nitrous acid The salt matrix makes AnAOB lack a suitable matrix ratio, causing the system to collapse; in addition, the high concentration of ammonia nitrogen in the influent water used by this technology and the large amount of water lead to a high total nitrogen removal load, but the concentration of ammonia nitrogen in the effluent still reaches about 150 mg / L, which cannot be approached. High processing requirements, need other processes to continue processing

[0009] CN108083581A discloses a low-energy autotrophic denitrification municipal sewage treatment system and method, which adopts the form of serial anaerobic decarburization-autotrophic denitrification to first inoculate the residual sludge of the sewage treatment plant to start the anaerobic carbon removal reactor, and the anaerobic decarbonization reactor involved The start-up process of the oxygen decarbonization reactor takes 60-90 days, and the subsequent start-up process of the autotrophic denitrification reactor needs to inoculate the whole pool with 3000 mg / L anammox sludge for early anaerobic start-up, and artificially distribute water to meet the anaerobic requirements. Ammonia oxidizing bacteria substrate requirements, the reactor start-up process takes 90-120 days, and the whole process starts up 150-210 days. The pre-anaerobic decarbonization tank of this method uses a sludge system, and it is easy for the sludge to enter the post-treatment system after long-term operation. It affects the whole process, and sludge bulking is prone to occur. In addition, this method requires too much anammox bacteria, making inoculation difficult and difficult to achieve long-term large-scale expansion of multiple projects. The manual water distribution in the early stage was successfully started. There is a certain risk of whether the anammox strains can adapt to the actual wastewater

This method also has too much demand for provenance microbial biomass, which is difficult to meet the start-up of large-scale engineering projects, and the start-up process is water distribution operation, so it is impossible to predict whether the cultivated autotrophic denitrification functional microorganisms can use the actual engineering water quality, and the sponge filler can be used in actual projects. It is easy to wear during operation, and when the biofilm forms a certain thickness, it is prone to clogging, which affects mass transfer or the filler becomes heavy and hinders fluidization.

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