Device and method for strengthening autotrophic nitrogen removal and synchronous phosphorus recovery of nitrate wastewater through alkaline sludge fermentation

Abstract

The invention discloses a device and a method for strengthening autotrophic nitrogen removal and synchronous phosphorus recovery of nitrate wastewater through alkaline sludge fermentation. The devicecomprises an alkaline sludge fermentation coupling short-cut denitrification reactor and an autotrophic nitrogen removal and synchronous phosphorus recovery reactor. According to the method, under analkaline condition, hydrolysis acid production of remaining sludge is accelerated, a micromolecular organic carbon source is generated, and a large amount of ammonia nitrogen and phosphorus are released; under a high pH condition and a high fermentation environment, denitrifying bacteria are promoted to reduce nitrate into nitrite by using short-chain fatty acid, the nitrite and part of ammonia nitrogen generated by fermentation are removed under the action of anaerobic ammonia oxidizing bacteria, and the remaining ammonia nitrogen and phosphorus released by fermentation are separated and recovered in a struvite precipitation form; and the formed precipitate is beneficial to the granular growth and enrichment of anaerobic ammonium oxidation bacteria. According to the invention, by utilizing a novel short-cut denitrification and anaerobic ammonia oxidation coupled denitrification process, nitrogen pollutants in sludge and sewage are synchronously removed, and nitrogen and phosphorus resources are recovered, so that the device and the method have important economic and environmental benefits.

Description

technical field [0001] The invention relates to a process technology for alkaline sludge fermentation to strengthen nitrate wastewater autotrophic denitrification and simultaneous phosphorus recovery, belonging to the field of sewage biological treatment. Background technique [0002] With the continuous increase of sewage treatment in my country, the sludge output of urban sewage treatment plants is also increasing. By the end of 2017, the sludge production of sewage treatment plants in my country exceeded 40 million tons (according to the water content of 80% per 10,000 tons of sewage treated) 5 to 8 tons of sludge is calculated). Activated sludge has complex components and contains a large amount of organic pollutants, bacterial cells and other harmful substances. If it is not properly treated and discharged into the environment, it will cause serious secondary pollution to soil, surface water and groundwater. On the other hand, nutrients such as organic matter, nitrogen ...

AI Technical Summary

Problems solved by technology

However, there are still some limitations in the practical application of anaerobic ammonium oxidation technology. The substrates of the reaction process are ammonia nitrogen and nitrite. Wastewater, metal smelting industrial wastewater, ion exchange concentrated wastewater, etc., anaerobic ammonia oxidation technology cannot be directly applied to the denitrification treatment of such wastewater

The traditional biological denitrification method needs to add a large amount of organic carbon sources to treat nitrate wastewater, which not only consumes organic resources, but also produces a large amount of excess sludge, which increases the cost and energy consumption of sludge treatment and disposal.

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