Integrated wastewater treatment equipment is suitable for residential communities, villages, townships, office buildings, shopping malls, hotels, restaurants, sanatoriums, government agencies, schools, hospitals, highways, railways, stations, factories, mines, and tourist attractions for the treatment and reuse of domestic wastewater and similar small and medium-sized industrial organic wastewater from slaughtering, aquatic product processing, and food industries. The wastewater treated by this equipment meets the national comprehensive discharge standard B for wastewater treatment. The main treatment method is the biochemical treatment technology of contact oxidation. The design of the integrated domestic wastewater treatment equipment is mainly based on the quality parameters of domestic wastewater and similar industrial organic wastewater, with the influent BOD5 calculated at 200 mg/L.

Key Components: 1. Hydrolysis and Acidification Tank; 2. Contact Oxidation Tank; 3. Sedimentation Tank for Impurities; 4. Disinfection Treatment; 5. Anaerobic Digestion Tank for Sludge.

Hydrolysis and Acidification Tank

This process primarily focuses on the pretreatment of wastewater before it undergoes further treatment. It involves a certain degree of anaerobic fermentation of the wastewater to enhance its biodegradability, which is a crucial step before actual wastewater treatment. This step directly impacts the efficiency and duration of subsequent treatment processes, and can significantly improve treatment efficiency and reduce consumption.

2. Contact oxidation pond

The oxidation ponds are categorized into several levels based on the degree of water pollution, including standard and enhanced types. The classification is typically determined by the treatment time. Standard oxidation ponds are used for treatment times not exceeding four hours, while enhanced oxidation ponds are utilized for treatment times between 4 to 6 hours. The primary process involves the self-flow of effluent from the hydrolysis and acidification pond to the contact oxidation pond for biochemical treatment. Most organic matter in the raw wastewater is degraded and purified here. The aerobic bacteria, using the media as a carrier, feed on the organic matter in the wastewater, decomposing it into inorganic salts, thereby achieving purification. The survival of aerobic bacteria requires sufficient oxygen, which is ensured by adequate dissolved oxygen in the wastewater to achieve the biochemical treatment goal. The air for the aerobic pond is supplied by a fan, and the pond uses a new type of elastic three-dimensional media with a large surface area, long service life, easy biofilm formation, and resistance to corrosion. The bottom of the pond employs a rotational mixing aeration device, which ensures a high transfer rate of dissolved oxygen. This device also boasts advantages such as light weight, non-aging, non-clogging, and a long service life. The gas-to-water ratio in the contact pond is approximately 12:1 (0.5-5 m/h contact pond is classified as second stage).

3. Sedimentation Pool for Impurities

Wastewater flows into the sedimentation tank after being treated in a biological contact oxidation pond, where it further settles to remove detached biological slimes and some organic and inorganic particles. The sedimentation tank operates based on the principle of gravity. As the wastewater containing suspended solids moves downward, gravity causes the particles to settle. An adjustable overflow weir is installed at the upper part of the tank to regulate the water level. At the lower part, a conical sedimentation zone and a sludge gas handling unit are set up. The gas supply is provided by a fan, and sludge is transported to the sludge aerobic digestion tank via a gas-lifting method.

Sanitization processing

The disinfection pool adheres to the standard "TJ14-74" with a 30-minute cycle. For hospital wastewater, the retention time in the disinfection pool is extended to 1-1.5 hours. Our company utilizes a chlorine dioxide disinfection system, where the disinfection pool and the system adjust the dosage of disinfectant based on the water output, ensuring more disinfectant is added with higher output and less with lower output. Additional equipment can be customized as needed. (For industrial wastewater, the disinfection pool and system may not be necessary.)

5. Anaerobic Digestion Sludge Pond

The remaining sludge from the sedimentation pond undergoes aerobic digestion and stabilization treatment within the pond to reduce the sludge volume and enhance its stability. The sludge volume after aerobic digestion is reduced, allowing for its removal using a vacuum truck by extending into the bottom of the sludge pond through inspection openings (cleaned every six months). An upper clear liquid recirculation device is installed above the aerobic digestion pond, allowing the overflow of the clear liquid to be recycled into the hydrolysis and acidification pond.