A sewage treatment system and process based on carbon and nitrogen separation

Abstract

The invention provides a sewage treating system and process based on carbon-nitrogen separation. The sewage treating system comprises a constant temperature heating system, a rapid coagulation reactor, a first-stage separation reactor, an anaerobic reactor, an ammoxidation reactor, a denitrification reactor, a post-aeration reactor and a second-stage separation reactor, wherein a sludge return system is arranged at the bottom part of the anaerobic reactor, so that sludge returns to the rapid coagulation reactor and circulates to the first-stage separation reactor for circulating absorption; and the rapid coagulation reactor, the first-stage separation reactor, the anaerobic reactor and the ammoxidation reactor are respectively provided with an insulating device. The sewage treating system and process provided by the invention are applicable to engineering for treating waste water containing organic matters with medium-high concentration and total nitrogen, the process combines the traditional anaerobic-aerobic process and a sludge-absorbing water feeding and short-distance nitrification technology for overcoming the defects of low energy production efficiency, poor denitrification effect, higher energy consumption and the like in the traditional anaerobic-aerobic treatment process, and the process is a sewage treating process with the effects of low operation cost and less engineering investment as well as decarbonization and denitrification effects and energy-saving and energy-producing effects.

Description

technical field [0001] The invention belongs to the technical field of sewage treatment in the discipline of environmental engineering, and in particular relates to a sewage treatment system and process based on carbon and nitrogen separation. Background technique [0002] In recent years, the high-concentration organic wastewater treatment technology has shifted from the traditional single pretreatment + activated sludge method to a more intensive and energy-saving anaerobic-aerobic combined treatment method. However, the combined anaerobic-aerobic treatment method for wastewater containing a high concentration of ammonia nitrogen in the raw water is more difficult to treat. It is often necessary to adopt physical and chemical pretreatment and then combine it with biochemical treatment methods according to the characteristics of wastewater quality. This treatment method has high investment costs, high operating costs, and is likely to cause secondary pollution. [0003] Du...

AI Technical Summary

Problems solved by technology

However, the anaerobic-aerobic combined treatment method for wastewater containing a high concentration of ammonia nitrogen in the raw water is more difficult to treat. It is often necessary to adopt physical and chemical pretreatment and then combine it with biochemical treatment methods according to the characteristics of wastewater quality.

This treatment method has high investment cost, high operating cost, and is easy to cause secondary pollution

[0003] Due to the excessive nitrogen content in the anaerobic methanogenesis system, the pH value may rise above 8.0, and the ammonium salt of fatty acids will accumulate, which will inhibit the decomposition of organic matter; the denitrification process will cause the sedimentation of anaerobic sludge to decrease, resulting in The stability of the system deteriorates; at the same time, NO 2 -N / NO 3 -N and the intermediate products of denitrification are toxic to methane bacteria. The combination of the above reasons directly leads to the instability of the anaerobic reactor and the decline in the quality of gas produced by the anaerobic system.

[0004] During the denitrification process, more carbon sources are used by denitrifying bacteria to produce nitrogen and consume a large amount of organic carbon sources, resulting in a reduction in methane production in the system, reducing the utilization efficiency of carbon sources in the system, and destroying the anaerobic reactor. Advantage

[0005] Due to the high content of total nitrogen in the sewage, the ammonia nitrogen load in the sewage will inevitably become the limiting factor in the design of the aerobic tank in the subsequent design of the aerobic treatment system. cost increase

At the same time, the dissolved oxygen consumed in the ammonia nitrogen oxidation process must also be the main limiting factor of the system air volume, and the system operation cost is relatively high

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