Underwater As3+ efficient biological oxidation method

Abstract

Provided is an underwater As3+ efficient biological oxidation method and belongs to the field of water treatment. The invention includes the following steps: step (1) establishment of biological oxidation filtering pool; step (2) As3+ oxidization bacterination; step (3) a bacterial culture domestication process after the As3+ oxidization bacterination; step (4) raw water containing the As3+ is oxygenated by aeration, dissolved oxygen DO is controlled in 4mg / L-5mg / L and is inflated into the biological oxidation filtering pool and then the As3+ is oxygenized into As5+; (5) bacteria residual bodies and free floating bacteria are cleaned by utilizing the process of the filtering pool back wash to keep balance of biomass live weight in the biological oxidation filtering pool. The invention provides a method utilizing biotechnology to oxygenate the As3+ to form the As5+. The method is simple and efficient in process. Utilizing biological catalysis oxidation function of the As3+ oxygenating bacteria, the whole process only needs simple aeration and the dissolved oxygen Do is controlled in 4mg / L-5mg / L without any chemical oxidant so as to be friendly to environment.

Description

Technical field:

[0001] The invention relates to the field of water treatment. Background technique:

[0002] In the removal process of As in water, there are two links, namely As 3+ must first be oxidized to As 5+ , and then the efficient and complete removal of As can be achieved by adsorption, filtration or membrane filtration technology. In these two links, As 3+ Oxidized to As 5+ Steps determine the complexity and economy of the entire As removal process. The present invention specifically utilizes the As 3+ Bacteria with the ability to oxidize, build up As 3+ Biological oxidation filter, the arsenic-containing raw water is simply aerated, and the As in the water is reduced without adding any other chemical oxidizing substances. 3+ Efficient and rapid oxidation to form As in filters 5+ , creating good preconditions for the complete removal of As in water.

[0003] In natural water bodies, arsenic mainly exists in two forms: inorganic and organic. In general, i...

Examples

Embodiment example 1

[0040] Raw water As 3+ The concentration is 2.3mg / L, the carrier of the biological oxidation filter is quartz sand, the thickness of the filter layer is 1.0m, and the thickness of the supporting layer is 0.3m. The first inoculation method mentioned above is used for inoculation. The concentration of the inoculum suspension was 10 6 / ml, the total inoculum volume for three times is 3L. The filtration rate of the filter is 13m / h. The backwash intensity is 10L / m 2 .s, the backwash lasts 3 minutes, and the backwash cycle is 96 hours. Effluent As 3+ The concentration is 0.006mg / L, and the oxidation rate is 99.74%.

Embodiment example 2

[0042] Raw water As 3+ The concentration is 2.3mg / L, the carrier of the biological oxidation filter is quartz sand, the thickness of the filter layer is 1.0m, and the thickness of the support layer is 0.3m. The second inoculation method mentioned above is used for inoculation. The bacterial suspension concentration was 10 6 cells / ml, the total amount is 3L, and the bacterial suspension is concentrated to 30ml after centrifugation. Bacteria are fixed and embedded, and combined with quartz sand to make a carrier filler with bacterial biological activity, which is directly loaded into the filter tank. The filtration rate of the filter is 13m / h. The backwash intensity is 10L / m 2 .s, the backwash lasts 3 minutes, and the backwash cycle is 96 hours. Effluent As 3+ The concentration is 0.008mg / L, and the oxidation rate is 99.65%.

Technical field:

[0001] The invention relates to the field of water treatment. Background technique:

[0002] In the removal process of As in water, there are two links, namely As 3+ must first be oxidized to As 5+ , and then the efficient and complete removal of As can be achieved by adsorption, filtration or membrane filtration technology. In these two links, As 3+ Oxidized to As 5+ Steps determine the complexity and economy of the entire As removal process. The present invention specifically utilizes the As 3+ Bacteria with the ability to oxidize, build up As 3+ Biological oxidation filter, the arsenic-containing raw water is simply aerated, and the As in the water is reduced without adding any other chemical oxidizing substances. 3+ Efficient and rapid oxidation to form As in filters 5+ , creating good preconditions for the complete removal of As in water.

[0003] In natural water bodies, arsenic mainly exists in two forms: inorganic and organic. In general, i...

Examples

Embodiment example 1

[0040] Raw water As 3+ The concentration is 2.3mg / L, the carrier of the biological oxidation filter is quartz sand, the thickness of the filter layer is 1.0m, and the thickness of the supporting layer is 0.3m. The first inoculation method mentioned above is used for inoculation. The concentration of the inoculum suspension was 10 6 / ml, the total inoculum volume for three times is 3L. The filtration rate of the filter is 13m / h. The backwash intensity is 10L / m 2 .s, the backwash lasts 3 minutes, and the backwash cycle is 96 hours. Effluent As 3+ The concentration is 0.006mg / L, and the oxidation rate is 99.74%.

Embodiment example 2

[0042] Raw water As 3+ The concentration is 2.3mg / L, the carrier of the biological oxidation filter is quartz sand, the thickness of the filter layer is 1.0m, and the thickness of the support layer is 0.3m. The second inoculation method mentioned above is used for inoculation. The bacterial suspension concentration was 10 6 cells / ml, the total amount is 3L, and the bacterial suspension is concentrated to 30ml after centrifugation. Bacteria are fixed and embedded, and combined with quartz sand to make a carrier filler with bacterial biological activity, which is directly loaded into the filter tank. The filtration rate of the filter is 13m / h. The backwash intensity is 10L / m 2 .s, the backwash lasts 3 minutes, and the backwash cycle is 96 hours. Effluent As 3+ The concentration is 0.008mg / L, and the oxidation rate is 99.65%.

Images