CN-121823847-A - Semi-coke wastewater treatment method

CN121823847ACN 121823847 ACN121823847 ACN 121823847ACN-121823847-A

Abstract

The invention discloses a semi-coke wastewater treatment method, which comprises the steps of recycling semi-coke through phenol and ammonia to form semi-coke wastewater, introducing the semi-coke wastewater into a high-load enhanced aerobic unit, a chemical destabilizing high-efficiency oxidation unit and an AO biochemical treatment unit which are sequentially connected, wherein the high-load enhanced aerobic unit comprises a high-load aerobic tank and a sedimentation tank, mixing the semi-coke wastewater in the high-load aerobic tank with domesticated activated sludge for aeration, introducing a mud-water mixture formed after aeration into the sedimentation tank for sewage separation, sequentially carrying out chemical destabilizing, primary sedimentation, high-efficiency oxidation reaction, coagulation flocculation and secondary sedimentation on upper wastewater separated by the sedimentation tank in the chemical destabilizing high-efficiency oxidation unit, sequentially carrying out primary anoxic tank, primary aerobic tank, secondary anoxic tank, secondary aerobic tank and biochemical sedimentation on supernatant after secondary sedimentation in the AO biochemical treatment unit, and recycling the treated water. The invention reduces the dosage of the medicament, reduces the output of the residual sludge, reduces the energy consumption and the operation cost, and improves the stability.

Inventors

WANG WENBIAO
FENG KAI
ZHENG SHAOJIE
YUE SIQI
CHEN HAO
ZHANG JINBIAO
HAN DONGCHUAN
HU QINGWEI

Assignees

上海泓济环保科技股份有限公司

Dates

Publication Date: 20260410
Application Date: 20251217

Claims (9)

1. The method for treating the semi-coke wastewater is characterized in that semi-coke wastewater is formed by recycling semi-coke through phenol ammonia; The semi-coke wastewater is introduced into a high-load enhanced aerobic unit, a chemical destabilization high-efficiency oxidation unit and an AO biochemical treatment unit which are sequentially connected, and the output treated water body is recycled; the high-load enhanced aerobic unit comprises a high-load aerobic tank and a sedimentation tank; The semi-coke wastewater is mixed with the domesticated activated sludge in the high-load aerobic tank for aeration; the mud-water mixture formed after aeration enters the sedimentation tank for sewage separation; the upper wastewater separated by the sedimentation tank enters the chemical breaking and stabilizing high-efficiency oxidation unit; The sludge concentration of the high-load aerobic tank is maintained at 8g/L to 12g/L; The chemical destabilization high-efficiency oxidation unit sequentially comprises chemical destabilization, primary precipitation, high-efficiency oxidation reaction, coagulation flocculation and secondary precipitation; firstly adding a chemical destabilizing agent into the upper wastewater separated by the sedimentation tank and stirring the chemical destabilizing agent to realize the chemical destabilization; Performing solid-liquid separation on the primary precipitation of the chemically-destabilized wastewater, and performing the efficient oxidation reaction on supernatant; the wastewater subjected to the efficient oxidation reaction is subjected to coagulation flocculation; Carrying out secondary sedimentation on the coagulated and flocculated wastewater; And the supernatant subjected to secondary sedimentation sequentially passes through a primary anoxic tank, a primary aerobic tank, a secondary anoxic tank, a secondary aerobic tank and a biochemical sedimentation tank in the AO biochemical treatment unit, and the treated water body is recycled.
2. The method for treating semi-coke wastewater according to claim 1, wherein the high-load enhanced aerobic unit further comprises a sludge regeneration tank; the sludge at the bottom of the sedimentation tank is pumped to the sludge regeneration tank through a sludge reflux pump; The sludge regenerated in the sludge regeneration tank enters the high-load aerobic tank to be used as the domesticated activated sludge; the sludge concentration of the sludge regeneration tank is controlled to be 15g/L to 20g/L.
3. The method for treating semi-coke wastewater according to claim 2, wherein 10mg/L to 50mg/L of the multi-functional nutrient for supplementing carbon sources, phosphorus sources and micro-growth auxiliary factors required by microorganisms is introduced into the sludge regeneration tank.
4. The method for treating semi-coke wastewater according to claim 1, wherein a composite biological modifier is added into the high-load aerobic tank; The composite biological modifier comprises a particle material with an adsorption-carrier synergistic effect and a functional regulating component for improving the flocculation structure and sedimentation performance of sludge.
5. The method for treating semi-coke wastewater according to claim 4, wherein the composite biological modifier comprises a porous adsorption matrix, a microporous biological carrier, an iron-based response particle, an alkaline coagulant aid and a cationic polymer; wherein the porous adsorption matrix comprises 5 to 20% by weight; The weight of the microporous biological carrier accounts for 50 to 70 percent; The weight of the iron-based response particles is 10 to 20 percent; the weight ratio of the alkaline coagulant aid to the cationic polymer is 5-10%.
6. The method for treating semi-coke wastewater according to claim 1, wherein the chemical destabilizing agent is an inorganic acidic solution; And adding a composite oxidant containing an activating component into the efficient oxidation reaction.
7. The method for treating semi-coke wastewater according to claim 1, wherein the primary aerobic tank is provided with a nitrifying liquid which flows back to the primary anoxic tank; after the biochemical sedimentation tank performs solid-liquid separation, the bottom sludge flows back to the primary anoxic tank.
8. The method for treating semi-coke wastewater according to claim 1, wherein a composite nutrient for supplementing carbon sources and micro-growth promoting factors required by denitrifying microorganisms is added to both the primary anoxic tank and the secondary anoxic tank.
9. The method for treating semi-coke wastewater according to claim 1, wherein fixed bed flat plate fillers are arranged in the primary aerobic tank and the secondary aerobic tank; The fixed bed flat plate filler is a flat plate flexible structural material, and the specific energy of the surface area and the surface roughness provides a stable adhesion growth interface for microorganisms.

Description

Semi-coke wastewater treatment method Technical Field The invention relates to the technical field of wastewater treatment, in particular to a semi-coke wastewater treatment method. Background The semi-coke is a solid fuel obtained by dry distillation of coal under medium and low temperature conditions, and the production process of the semi-coke can be accompanied with a large amount of circulating water and wastewater discharge in links of cooling, cleaning and the like. The waste water sources are various, and the waste water comprises the cooling bottom water of the carbonization furnace, the waste water generated in the coke quenching process, the oil-water mixed liquid discharged in the separation and collection link and the pollutants carried out in the circulating water of the system. Overall, the semi-coke wastewater has extremely complex components, and the detected pollutant types can reach hundreds. The organic pollutant has high content including various phenol compounds, tar component, benzene and its direct or indirect derivative, and great amount of polycyclic aromatic hydrocarbon, and the inorganic pollutant has high concentration of ammonia nitrogen, sulfide, cyanide, etc. The chromaticity of the wastewater is extremely deep, the Chemical Oxygen Demand (COD) can reach 30000-40000 mg/L, the ammonia nitrogen concentration is in the range of 5000-15000 mg/L, and even if the content of phenolic substances is low, the concentration is often more than 1800mg/L, thus having serious harm to the environment and biological systems. Therefore, it must be treated effectively to meet the relevant emission standards for discharge. At present, the systematic treatment technology of semi-coke wastewater is still in an exploration stage, and generally refers to a coking wastewater treatment route with similar components and water quality characteristics. In the prior engineering practice, the sectional treatment is generally adopted, namely, firstly, the physical and chemical pretreatment is carried out to recycle oil, available phenols and ammonia substances, and common methods comprise mechanical separation and oil removal, steam stripping and deacidification and deamination and organic solvent extraction and dephenolization. However, even after pretreatment, the wastewater remains a significant amount of nondegradable components and biologically toxic compounds, which can pose significant challenges for subsequent biochemical treatments. For example, inhibitory components such as phenols, cyanide, sulfide and the like can severely inhibit the activity of flora in a system at a concentration higher than a microbial tolerance threshold, and particularly the inhibition effect on nitrifying bacteria is more remarkable, and the nitrogen removal rate and the organic matter degradation rate are directly reduced, so that the system is low in operation efficiency and unstable. In the advanced treatment process, fenton oxidation, ozone oxidation or physical and chemical refining treatment technology based on an adsorbent is often adopted in order to further reduce the concentration of pollutants and improve the quality of effluent. Although the process can improve the treatment depth to a certain extent, the problems of high operation cost, high energy consumption, large medicament consumption and the like generally exist, and the process is unfavorable for large-scale long-term stable application. Therefore, how to reduce the dosage of the medicament, reduce the output of the residual sludge, reduce the energy consumption and the operation cost, improve the stability and simplify the operation and maintenance, not only reduce the volume of a treated structure, but also reduce the land occupation and the construction investment cost is a technical problem which needs to be solved by the technicians in the field. Disclosure of Invention In view of the above-mentioned shortcomings of the prior art, the invention provides a semi-coke wastewater treatment method, which aims to reduce the dosage of the agent, reduce the residual sludge yield, reduce the energy consumption and the operation cost, improve the stability, simplify the operation and maintenance, reduce the volume of the treated structure and reduce the land occupation and the construction investment cost. In order to achieve the above purpose, the invention discloses a semi-coke wastewater treatment method, which comprises the steps of recycling semi-coke preparation wastewater through phenol ammonia to form semi-coke wastewater; The semi-coke wastewater is introduced into a high-load enhanced aerobic unit, a chemical destabilization high-efficiency oxidation unit and an AO biochemical treatment unit which are sequentially connected, and the output treated water body is recycled; the high-load enhanced aerobic unit comprises a high-load aerobic tank and a sedimentation tank; The semi-coke wastewater is mixed with the domesticated activated sludge in the hi