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CN-121990683-A - Sulfate type anaerobic hydroxylamine oxidation high-efficiency denitrification method

CN121990683ACN 121990683 ACN121990683 ACN 121990683ACN-121990683-A

Abstract

A sulfate type anaerobic hydroxylamine oxidation high-efficiency denitrification method belongs to the field of industrial sewage treatment. The invention aims to solve the problems that the existing denitrification technology still has unstable reaction, low denitrification efficiency and easy inhibition of microbial communities when dealing with complex wastewater containing hydroxylamine and sulfate. The method comprises the steps of preparing inoculated sludge, setting the running conditions of the reactor, and running the reactor. The method is used for efficient denitrification by oxidizing the acid salt type anaerobic hydroxylamine.

Inventors

  • ZHONG YUNNA
  • XIE GUOJUN
  • WU RUI
  • HU SHUSHAN
  • YANG TAO

Assignees

  • 广东粤海水务股份有限公司
  • 哈尔滨工业大学水资源国家工程研究中心有限公司
  • 哈尔滨工业大学

Dates

Publication Date
20260508
Application Date
20260304

Claims (10)

  1. 1. A sulfate type anaerobic hydroxylamine oxidation high-efficiency denitrification method is characterized by comprising the following steps: 1. Preparation of inoculation sludge: Pretreating anaerobic ammonia oxidation granular sludge, secondary sedimentation tank activated sludge and river sediment, and uniformly mixing to obtain mixed liquor; The concentration of suspended solids in the mixed solution is 8.5g SS L -1 ~10.5g SS L -1 ; The mass ratio of the anaerobic ammonia oxidation granular sludge to the secondary sedimentation tank activated sludge to the river sediment is 2 (0.6-1.2); 2. Reactor operating conditions set up: Before inoculation, removing residual oxygen in the reactor, establishing an anaerobic environment, setting the reactor to operate in a double water inlet mode, respectively feeding hydroxylamine solution and sulfate solution, controlling the flow rate through a peristaltic pump, and then introducing the mixed solution into the reactor to serve as an inoculum; 3. The reactor is operated: ① The reactor is operated from day 1 to day 21, the hydraulic retention time is set to be 16-18 days, and the low hydroxylamine water inlet load is maintained; ② The hydraulic retention time is set to be 11-15 days from 22 days to 75 days when the reactor is operated, so that the hydroxylamine water inlet load is further improved; ③ The operation of the reactor is carried out for 76 to 168 days, the hydraulic retention time is set to 9 to 11 days, and the water inlet load of the hydroxylamine is increased to be high, thus the sulfate type anaerobic hydroxylamine oxidation high-efficiency denitrification method is completed.
  2. 2. The sulfate-type anaerobic hydroxylamine oxidation high-efficiency denitrification method according to claim 1, wherein the particle size of the anaerobic ammonia oxidation granular sludge in the first step is more than 0.5mm, and SVI is 20 mL/g-40 mL/g.
  3. 3. The sulfate type anaerobic hydroxylamine oxidation high-efficiency denitrification method according to claim 1, wherein the MLSS of the secondary sedimentation tank activated sludge in the first step is 7000mg/L to 10000mg/L.
  4. 4. The method for efficiently denitrifying sulfate-type anaerobic hydroxylamine oxidation according to claim 1, wherein the mass percentage of gravel in the river sediment in the step one is lower than 15%.
  5. 5. The sulfate type anaerobic hydroxylamine oxidation high-efficiency denitrification method according to claim 1, wherein the pretreatment of the anaerobic ammonia oxidation granular sludge and the secondary sedimentation tank activated sludge in the first step is to clean by using a culture medium, and the pretreatment of the river sediment in the first step is to remove coarse particle impurities by filtering through a screen after the river sediment and the culture medium are uniformly mixed.
  6. 6. The sulfate type anaerobic hydroxylamine oxidation high-efficiency denitrification method according to claim 1, wherein in the third ①, the low hydroxylamine water inflow load is maintained, specifically, hydroxylamine water inflow load rate is 3.8mg N L -1 d -1 ~5.7mg N L -1 d -1 , and sulfate water inflow load rate is 2.3mg S L -1 d -1 ~3.9mg S L -1 d -1 .
  7. 7. The sulfate type anaerobic hydroxylamine oxidation high-efficiency denitrification method according to claim 1, wherein in the step III ②, the hydroxylamine water inlet load is further improved, specifically, the hydroxylamine water inlet load rate is 8.6mg N L -1 d -1 ~11.5mg N L -1 d -1 , and the sulfate water inlet load rate is 2.3mg S L -1 d -1 ~3.9mg S L -1 d -1 .
  8. 8. The sulfate type anaerobic hydroxylamine oxidation high-efficiency denitrification method according to claim 1, wherein the step III ③ is characterized in that the high hydroxylamine water inlet load is specifically hydroxylamine water inlet load rate of 13.8mg N L -1 d -1 ~14.4mg N L -1 d -1 and sulfate water inlet load rate of 2.3mg S L -1 d -1 ~3.9mg S L -1 d -1 .
  9. 9. The method for efficient denitrification of sulfate-type anaerobic hydroxylamine oxidation according to claim 1, wherein the pH of the reactor is 7.0-8.0 in the operation cycle of steps three ①、② and ③.
  10. 10. The method for efficient denitrification of sulfate-type anaerobic hydroxylamine oxidation according to claim 1, wherein the temperature in the operation cycle of steps three ①、② and ③ is 30±2 ℃.

Description

Sulfate type anaerobic hydroxylamine oxidation high-efficiency denitrification method Technical Field The invention belongs to the field of industrial sewage treatment. Background With the continuous increase of the discharge amount of industrial and municipal wastewater, the problem of nitrogen-containing and sulfur-containing composite pollution is increasingly prominent. Waste water from industries such as chemical industry, coking industry, smelting industry, pharmacy industry, landfill leachate industry and the like often contains high-concentration hydroxylamine (NH 2 OH) and sulfate (SO 42-) pollutants. If the complex wastewater is not fully treated and directly discharged, the complex wastewater not only can cause eutrophication of the receiving water body, but also can cause secondary pollution such as stink of hydrogen sulfide, heavy metal dissolution and the like, and the complex wastewater is a threat to the ecological system and human health. At present, a coupling process of sulfur autotrophic short-cut denitrification-anaerobic ammoxidation (Anamox) is often adopted for treating the wastewater containing nitrogen and sulfur. Wherein, sulfur autotrophic short-cut denitrification uses sulfide and the like as electron donors to reduce nitrate (NO 3-) and generate nitrite (NO 2-), and then cooperates with Anamox to improve denitrification efficiency. However, such processes are generally significantly limited by environmental conditions and intermediates, NO 2- salts act as key electron acceptors for Anamox, are susceptible to substrate fluctuations during operation, and are often limited by inadequate NO 2- supply. In addition, the system is sensitive to operating parameters such as pH, temperature, dissolved oxygen and the like, and is often characterized by long start-up domestication period and insufficient operating stability, so that the engineering popularization and application of the system are limited. In recent years, researchers have gradually discovered that NH 2 OH has a unique intermediate role in the nitrogen recycle system. Hydroxylamine can be used as an intermediate product of ammonia oxidation, and can be directly oxidized into nitrogen (N 2) by microorganisms under specific conditions, so that the NO 2- generation process is bypassed, and a novel anaerobic hydroxylamine oxidation denitrification path is realized. The method has the advantages of high reaction rate, low energy requirement, flexible substrate types and the like, and provides a new technical direction for high-efficiency autotrophic denitrification. However, the existing anaerobic hydroxylamine oxidation system still faces multiple challenges in engineering application, namely (1) the reaction mechanism is complex, the stability of functional flora is poor, the anaerobic hydroxylamine oxidation process involves hydroxylamine oxidizing bacteria, sulfate reducing bacteria and other multifunctional microorganisms, the metabolic pathways of the anaerobic hydroxylamine oxidation system are in cross coupling, and the anaerobic hydroxylamine oxidation system is easily influenced by fluctuation of inflow water quality and environmental conditions, so that the system is easy to be unstable and difficult to operate for a long time. (2) The intermediate products have obvious inhibition effect, namely, intermediate products such as sulfide, sulfite, elemental sulfur and the like are often generated in the sulfate reduction process, and the substances have potential toxicity to anaerobic hydroxylamine oxidizing bacteria, can inhibit the metabolic activity of the anaerobic hydroxylamine oxidizing bacteria, and cause the reduction of the reaction rate. (3) The lack of a substrate regulation mechanism is that the conversion of hydroxylamine as an electron donor or acceptor strongly depends on the oxidation-reduction state of a reaction system, but the lack of an effective substrate supply and electron flow regulation means in the prior art leads to large fluctuation of system operation and low reaction efficiency. In summary, the existing denitrification technology still has the problems of unstable reaction, low denitrification efficiency and easy inhibition of microbial communities when dealing with complex wastewater containing hydroxylamine and sulfate. Disclosure of Invention The invention aims to solve the problems that the existing denitrification technology still has unstable reaction, low denitrification efficiency and easy inhibition of microbial communities when dealing with complex wastewater containing hydroxylamine and sulfate, and further provides a sulfate type anaerobic hydroxylamine oxidation efficient denitrification method. A sulfate type anaerobic hydroxylamine oxidation high-efficiency denitrification method is carried out according to the following steps: 1. Preparation of inoculation sludge: Pretreating anaerobic ammonia oxidation granular sludge, secondary sedimentation tank activated sludge and river s