A method for synergistic denitrification and dephosphorization of nano-iron and microorganisms

Abstract

The invention provides a method for simultaneously removing phosphorous and nitrogen through the synergistic effect of nanoscale-iron and microbes. The method is characterized in that firstly limonite ore is broken and sieved so as to obtain particulate materials with the required particle size, the particulate materials mainly comprising nanoscale iron and having millimeter particle size and the porous structure characteristic are prepared through high temperature reduction under a hydrogen or carbon monoxide atmosphere, the nanoscale iron in the particulate materials slowly release nascent hydrogen atoms and hydrogen gas, and nitrate is chemically reduced; meanwhile, the particulate materials have relatively high void ratio, and abundant function anaerobic microbe denitrifying bacteria adhere to the inner parts and the outer surfaces of the particulate materials and reduce the nitrate by using hydrogen released through reaction between the nanoscale-iron and water as electron donors; adherent dependent nitrate iron-oxidizing bacteria also have the effect of reducing the nitrate; the nitrate in wastewater is removed under the chemical action of the nanoscale-iron and the synergistic effects of the anaerobic microbes; ferrous and ferric hydroxides are continuously formed on the inner surfaces and the outer surfaces of the porous particulate materials through the chemical reaction of the nanoscale-iron and water and the synergistic effect of the anaerobic microbes, so that the chemical adsorption of phosphorous in water is promoted, thus the effect of simultaneously removing phosphorous and nitrogen is achieved.

Description

1. Technical field [0001] The invention relates to a method for advanced treatment of slightly polluted water, in particular to a method for advanced treatment of domestic sewage for preventing water body eutrophication. 2. Background technology [0002] Due to my country's rapid economic development and accelerated urbanization, a large amount of nutrients nitrogen and phosphorus have entered lakes and other water bodies, resulting in serious eutrophication in lakes such as Chaohu Lake, Taihu Lake, Dianchi Lake and urban landscape water bodies. In order to control environmental pollution, the state has invested heavily in the construction of urban sewage treatment facilities to increase the treatment rate of urban domestic sewage. However, at present, the aerobic activated sludge process is commonly used in urban domestic sewage treatment, and scholars at home and abroad are also vigorously studying biological phosphorus removal technology, but the concentrations of total n...

AI Technical Summary

Problems solved by technology

However, the dosage of nano-iron is very high, and the mass ratio of nano-iron to nitrate nitrogen should reach 1:40, which shows that the reaction and utilization efficiency of nano-iron with nitrate and nitrite is not high, resulting in the reduction of nitrate in water treated by nano-iron , The cost of nitrite is high, and there are still obstacles in the promotion and application of technical and economic aspects

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