Method for deep denitriding of waste water in low carbon nitrogen ratio through denitrification

Abstract

The invention discloses a method for deep denitriding of waste water in a low carbon nitrogen ratio through denitrification. The method comprises the following steps: (1) performing denitriding by utilizing corn cores as an additional carbon source and a biomembrane carrier in a first section reactor A; (2) performing further denitriding by utilizing bamboo charcoal as a fixed bed to load microorganisms in a second section reactor B; (3) setting water inlet points respectively on the two sections of the reactors for raw water, and the water inlet points can be shifted in proportion according to different qualities of the raw water. The method has the following advantages that (1) an organic matter can be slowly released, secondary pollution cannot be generated, and the COD exceeding of effluent cannot be caused; (2) the method has a better removing effect on nitrate nitrogen in the waste water in the low carbon nitrogen ratio and besides can remove ammonia nitrogen in the waste water; (3) secondary pollution cannot be generated, and the standing time of the nitrate nitrogen can be prolonged, so that the quality of the effluent is improved; (4) the denitriding effect of the waste water can be improved, and the removing rate of the nitrate nitrogen is more than 80%, so that the effluent is steady; (5) the technology is simple, easy to operate, low in cost, small in floor space, short in standing time and free from power consumption, and the method has a good application prospect.

Description

technical field

[0001] The invention relates to a method for deep denitrification of sewage with a low carbon-to-nitrogen ratio and belongs to the technical field of water treatment. Background technique

[0002] At present, most sewage treatment plants in my country have a large amount of secondary effluent discharge, and face the problem of unstable effluent total nitrogen concentration (of which nitrate nitrogen accounts for about 78%), which cannot meet the first-level B standard for pollutant discharge of urban sewage treatment plants. Therefore, denitrification has become the main goal of advanced treatment of secondary effluent.

[0003] Ion exchange, reverse osmosis, and biological denitrification can all remove nitrate, but ion exchange and reverse osmosis processes have not been widely used because they cannot completely remove nitrate nitrogen, are expensive, and have high treatment costs.

[0004] The biological denitrification process is a cost-effective denitr...

Examples

Embodiment 1

[0027] (1) After the corn cob is exposed to the sun, cut it according to the specification of 1 cm, and put it in the reactor A, as a solid carbon source and a microbial film carrier;

[0028] (2) The bamboo charcoal made of bamboo is broken, sieved to obtain 2-4mm bamboo charcoal, soaked in clean water, and used for hanging film;

[0029] (3) Put soaked bamboo charcoal in fixed bed reactor B as biological filler, feed COD concentration of 100 mg / L, nitrate nitrogen concentration of 20 mg / L, ammonia nitrogen concentration of 4 mg / L, total phosphorus concentration The simulated wastewater is 1 mg / L, and the continuous water inlet method is used to hang the film. The removal rate of the indicator pollutants COD, nitrate nitrogen, and ammonia nitrogen in the effluent water remains basically stable, respectively 90%, 80%, and 98%. The film hanging is successful. ;

[0030] (4) Reactors A and B are connected in series, the incoming sewage passes through reactor A and then through ...

Embodiment 2

[0034] Other conditions are constant, change the nitrate nitrogen volume load in embodiment 1 to be 0.25kgNO 3 -N / (m 3 ·d), the hydraulic retention time of A reactor and B reactor are 1.6h and 0.3h respectively.

[0035] Utilize this inventive method to process domestic sewage, and processing result is as follows:

[0036] Influent COD concentration 42.60 mg / L, effluent COD concentration 5.09 mg / L; influent ammonia nitrogen concentration 3.47 mg / L, effluent ammonia nitrogen concentration 0.69 mg / L; influent nitrate nitrogen concentration 21.64 mg / L, effluent nitrate nitrogen concentration 3.90 mg / L.

technical field

[0001] The invention relates to a method for deep denitrification of sewage with a low carbon-to-nitrogen ratio and belongs to the technical field of water treatment. Background technique

[0002] At present, most sewage treatment plants in my country have a large amount of secondary effluent discharge, and face the problem of unstable effluent total nitrogen concentration (of which nitrate nitrogen accounts for about 78%), which cannot meet the first-level B standard for pollutant discharge of urban sewage treatment plants. Therefore, denitrification has become the main goal of advanced treatment of secondary effluent.

[0003] Ion exchange, reverse osmosis, and biological denitrification can all remove nitrate, but ion exchange and reverse osmosis processes have not been widely used because they cannot completely remove nitrate nitrogen, are expensive, and have high treatment costs.

[0004] The biological denitrification process is a cost-effective denitr...

Examples

Embodiment 1

[0027] (1) After the corn cob is exposed to the sun, cut it according to the specification of 1 cm, and put it in the reactor A, as a solid carbon source and a microbial film carrier;

[0028] (2) The bamboo charcoal made of bamboo is broken, sieved to obtain 2-4mm bamboo charcoal, soaked in clean water, and used for hanging film;

[0029] (3) Put soaked bamboo charcoal in fixed bed reactor B as biological filler, feed COD concentration of 100 mg / L, nitrate nitrogen concentration of 20 mg / L, ammonia nitrogen concentration of 4 mg / L, total phosphorus concentration The simulated wastewater is 1 mg / L, and the continuous water inlet method is used to hang the film. The removal rate of the indicator pollutants COD, nitrate nitrogen, and ammonia nitrogen in the effluent water remains basically stable, respectively 90%, 80%, and 98%. The film hanging is successful. ;

[0030] (4) Reactors A and B are connected in series, the incoming sewage passes through reactor A and then through ...

Embodiment 2

[0034] Other conditions are constant, change the nitrate nitrogen volume load in embodiment 1 to be 0.25kgNO 3 -N / (m 3 ·d), the hydraulic retention time of A reactor and B reactor are 1.6h and 0.3h respectively.

[0035] Utilize this inventive method to process domestic sewage, and processing result is as follows:

[0036] Influent COD concentration 42.60 mg / L, effluent COD concentration 5.09 mg / L; influent ammonia nitrogen concentration 3.47 mg / L, effluent ammonia nitrogen concentration 0.69 mg / L; influent nitrate nitrogen concentration 21.64 mg / L, effluent nitrate nitrogen concentration 3.90 mg / L.