Light-driven waste water nitrogen-removal method and equipment

Abstract

The invention relates to light-driven waste water nitrogen-removal method and equipment. The method is characterized in that a semiconductor photoanode, a resistor and a biological cathode of a nitrogen-removal biomembrane attached with electrodephile breathing are connected in series to form a nitrogen-removal circuit, the method comprises the following steps: introducing the to-be-processed sewage containing nitrate in a cathode chamber of electrochemical equipment; light irradiates the surface of the semiconductor photoanode to generate photo-induced electron; the photo-induced electron is conducted to biological cathode, the nitrogen-removal biomembrane attached with electrodephile breathing is used to complete nitrogen removal. According to the invention, light is taken as the only energy and electron source for microbe nitrogen removal, an electron donor is not added for exogenous part, extra electric energy is not required; the biological cathode is attached with the nitrogen-removal biomembrane attached with electrodephile breathing, microbe is taken as a catalyst for denitrification, and the method has the advantages of low cost, environmental protection and continuous development.

Description

technical field [0001] The invention belongs to the technical field of water treatment, and more specifically relates to a light-driven wastewater denitrification method and equipment. Background technique [0002] Nitrate is one of the most common pollutants in water bodies. In the sewage treatment system, due to insufficient carbon-to-nitrogen ratio in sewage, a large amount of nitrate remains in the effluent, which cannot meet the requirements of the total nitrogen standard. The discharge of nitrate into the environmental water body along with the sewage is one of the important factors causing the eutrophication of the water body; at the same time, the nitrate also has great hidden dangers to human health, and is a key factor in inducing degenerative hemoglobinemia. Therefore, in drinking water treatment Nitrate is also an important control indicator. The denitrification method of reducing nitrate to harmless nitrogen is the most important means to remove nitrate in wate...

AI Technical Summary

Problems solved by technology

However, in many water quality situations (such as the secondary effluent of sewage treatment plants and surface water), the electron donor content available to these microorganisms is extremely low, and it is necessary to artificially add electron donors to the water, which undoubtedly greatly increases the removal of nitrate. processing cost

At the same time, other problems caused by the existing method of adding electron donors from external sources cannot be ignored. For example, when adding organic electron donors such as methanol and glucose, they may be excessively added due to fluctuations in the concentration of nitrate in water, resulting in secondary pollution. secondary pollution; at the same time, due to the rapid proliferation of heterotrophic microorganisms, frequent backwashing of the system is required, which further increases energy consumption

Although the autotrophic biological denitrification process with hydrogen addition can better avoid secondary pollution and excessive microbial proliferation, there are certain safety hazards in the storage and use of hydrogen, which limits the wide application of this technology

Images