The integrated sewage treatment equipment is a device that integrates the first sedimentation tank, first and second stage contact oxidation tanks, second sedimentation tanks, and sludge tanks, and conducts air blowing and aeration in the first and second stage contact oxidation tanks, effectively combining the contact oxidation method and activated sludge method, while possessing the advantages of the two and overcoming their shortcomings, further improving the level of sewage treatment.

1、 Description of sewage treatment process flow

This project adopts the biofilm method: anoxic aerobic (A/0) treatment process. The A/O (anoxic+aerobic biological contact oxidation) process is a mature biological treatment process that has the advantages of high volumetric load, fast biodegradation speed, small footprint, low infrastructure investment and operating costs. It can replace the ordinary activated sludge method used in urban sewage treatment, and is particularly suitable for the treatment of medium and high concentration industrial wastewater, with low investment, less land occupation, and high treatment efficiency. The process adopts a combination of biological contact oxidation and precipitation, which is mature and reliable. The sludge is precipitated in the equipment, and a portion of the sludge is further oxidized and decomposed due to the action of dissolved oxygen. A portion of the sludge is pumped to the sand settling tank, and the system sludge only needs to be regularly pumped in the sand settling tank. The working programs of the main control equipment such as the wind turbine and submersible sewage pump in the system are fed into the PLC machine to achieve automatic operation, reducing operational workload and unnecessary human damage.

1. Grille:

The sewage discharged from production is collected through the pipeline network system, and then enters the subsequent treatment system after passing through the coarse grid. Coarse grids are mainly used to intercept large floating objects in sewage, ensuring the normal operation of subsequent treatment structures and effectively reducing treatment loads, providing assurance for the long-term normal operation of the system.

2. Sewage regulation tank:

Used to regulate water volume and uniform water quality, so that sewage can enter the subsequent treatment unit more evenly. Setting up a pre aeration system in the regulating tank can improve the impact resistance of the entire system, reduce the foul odor of sewage in anaerobic conditions, and reduce the design scale of subsequent treatment units. A submersible sewage pump is installed in the sewage tank to lift the sewage to the subsequent treatment units.

3. Anoxic pool:

Install elastic fillers in the anoxic tank to intercept small suspended solids in wastewater and remove some organic matter. The nitrification solution from the anoxic tank after reflux is used for denitrification and denitrification, which improves the removal rate of ammonia nitrogen in wastewater. The sewage after anaerobic treatment enters the aerobic biological treatment tank.

4. Contact oxidation tank:

Most of the organic matter in the original wastewater is degraded and purified here. Aerobic bacteria use fillers as carriers and organic matter in wastewater as food to decompose the organic matter into inorganic salts, thus achieving the purpose of purification. The survival of aerobic bacteria requires sufficient oxygen, that is, sufficient dissolved oxygen in sewage, to achieve the purpose of biochemical treatment. The air in the aerobic tank is provided by a fan, and a new type of semi soft biological filler is used inside the tank. The filler has a large surface area ratio, long service life, easy film formation, and corrosion resistance. The bottom of the tank is equipped with a microporous aerator, which increases the transfer rate of dissolved oxygen. At the same time, it has the advantages of light weight, non aging, non clogging, and long service life. Two major accessories in the contact oxidation tank:

Filler: This process adopts a new type of three-dimensional elastic filler, which is a dense and efficient biochemical filler. The filler has advantages such as large specific surface area, long service life, easy film formation, and corrosion resistance. At the same time, the filler has a certain degree of stiffness, which can cut the bubbles in the sewage at multiple levels, increasing the efficiency of dissolved oxygen. Additionally, it is not easy to agglomerate between the filler and the filler, avoiding blockage of the oxidation tank.

Aerator: This process uses a microporous aerator, which has a higher dissolved oxygen transfer rate than other aerators. Its biggest characteristics are non aging, light weight, long service life, and it also has advantages such as corrosion resistance and non clogging.

5. Sedimentation tank:

After being treated in a biological contact oxidation tank, the effluent flows into a secondary sedimentation tank to further precipitate and remove the detached biofilm and some organic and inorganic small particles. The sedimentation tank is based on the principle of gravity, and when wastewater containing suspended solids flows from bottom to top, gravity acts as a force to precipitate the substances. The effluent after sedimentation in the secondary sedimentation tank is clearer and more transparent. The secondary sedimentation tank is a vertical flow sedimentation tank, which uses a sludge pump to regularly lift mud and gas into the sludge digestion tank. The treated water after sedimentation enters the subsequent treatment equipment.

6. Disinfection tank：

After sedimentation, the virus and Escherichia coli indicators of the sewage still do not meet the discharge standards. In order to eliminate the virus and Escherichia coli, chlorine disinfectant is added for disinfection treatment, and a folded plate form is used to directly discharge into nearby municipal pipelines relying on its own gravity.

7. Sludge digestion tank:

The remaining sludge discharged from the sedimentation tank is subjected to aerobic digestion and stabilization treatment in the tank to reduce the volume of sludge and improve its stability. The amount of sludge after aerobic digestion is relatively small. Regularly contact the environmental sanitation department for sludge removal and transportation or for sludge dewatering treatment and transportation. The supernatant is refluxed to the regulating tank using the supernatant.

8. Fan:

Used for air supply to the contact oxidation tank, pre aeration of the regulating tank, and aerobic digestion treatment of the sludge digestion tank.

2、 Introduction to Integrated Sewage Treatment Equipment

1. The sewage treatment consists of a secondary pool, made of steel structure with a shallow burial depth. The steel structure pool adopts the domestically pioneered interpenetrating network anti-corrosion coating for anti-corrosion. It is an interpenetrating polymer network formed by the interpenetration of rubber and plastic networks. It is resistant to acid, alkali, salt, gasoline, kerosene, aging, impact and wear, and can bring rust and rust prevention. After applying this coating to the equipment, the anti-corrosion life can generally reach more than 12 years.

2. The AO biological treatment process in sewage treatment equipment adopts a push flow biological contact oxidation tank, which is superior to a fully mixed or two or three stage series fully mixed biological contact oxidation tank for treatment. And it has a smaller volume than activated sludge tanks, strong adaptability to water quality, good impact resistance, stable effluent quality, and no sludge bulking. At the same time, a new type of elastic three-dimensional filler has been used in the biological contact oxidation tank, which has a large actual specific surface area and is convenient for microbial biofilm formation and removal. Under the same organic load conditions, it has a higher removal rate of organic matter than other fillers and can improve the solubility of oxygen in air in water.

3. Due to the use of a biological contact oxidation tank in the AO biological treatment process, the volumetric load of the filler is relatively low, and the microorganisms are in the stage of self oxidation, resulting in a relatively low sludge production. In addition, the moisture content of the sludge produced by the biological contact oxidation tank is much lower than that of the sludge produced by the activated sludge tank. Therefore, the amount of sludge generated by sewage treatment equipment is relatively small, and generally only needs to be discharged once in about 90 days.

4. The integrated sewage treatment equipment not only adopts conventional blower noise reduction measures (such as vibration isolation pads, silencers, etc.), but also sets up new sound-absorbing materials on the inner wall of the blower room, making the noise during operation less than 50 decibels, reducing the impact on the surrounding environment.

5. The fiberglass integrated sewage treatment equipment is equipped with a fully automatic electrical control system and equipment damage alarm system, ensuring good equipment reliability.

6. The integrated sewage treatment equipment can be buried below the surface, and the surface can be used as green or square land. Therefore, this equipment does not occupy the surface area, does not require building houses, and does not require heating and insulation.

(Source: New Horizon of Water Treatment)