A dairy plant generated substantial wastewater due to large-scale production, with initial simple treatment proving ineffective. After professional intervention, an efficient treatment process was designed:

Wastewater first passes through a mechanical bar screen to intercept large solids like curds and packaging fragments. It then enters an oil separation tank to separate milk fats and casein particles via sedimentation.

Subsequently, the dissolved air flotation (DAF) system utilizes chemicals and microbubbles to remove suspended solids and partial organic matter.

The pre-treated wastewater flows into a UASB (Upflow Anaerobic Sludge Blanket) reactor, where organic matter is decomposed by granular sludge under anaerobic conditions, producing biogas. In the following bio-contact oxidation tank, microorganisms degrade remaining organic matter and remove ammonia nitrogen under aerobic conditions.

Finally, disinfection ensures the effluent meets discharge standards. The plant also achieved resource recovery: biogas is used for on-site power generation, reducing operational costs. Additionally, sludge production was significantly minimized, alleviating disposal burdens. Treatment costs per tonne of wastewater were effectively controlled, achieving a true environmental and economic win-win.

To reduce production costs and minimize water waste, a small to medium-sized slaughterhouse implemented a wastewater reuse system. After research and comparison, the facility selected the following treatment process:
Pretreatment + Flotation + Coagulation-Sedimentation + Anaerobic Treatment + Aerobic Treatment + Advanced Treatment + Reuse.

The specific steps are as follows:

Pretreatment Stage:
Wastewater passes through a bar screen for debris removal and enters an equalization tank for homogenization, eliminating large suspended solids and stabilizing water quality/quantity.

Primary Treatment Stage:
Dissolved Air Flotation (DAF) is used to remove oils and suspended solids. This is followed by coagulation-sedimentation to further eliminate colloidal substances and suspended particles.

Biological Treatment Stage:

Anaerobic Treatment: Utilizes hydrolytic acidification technology to break down complex organic compounds into simpler molecules.

Aerobic Treatment: Effluent then enters an aerobic unit employing a bio-contact oxidation process to degrade residual organic matter, ammonia nitrogen, and other pollutants.

Advanced Treatment Stage:
Ultrafiltration (UF) membrane separation removes micro suspended particles, dissolved organic matter, odor compounds, and other contaminants, significantly enhancing effluent quality.

Reuse Stage:
The treated wastewater meets reuse standards for production processes. It is recycled for slaughterhouse cleaning, toilet flushing, and other non-potable purposes, achieving closed-loop water reuse.

A cold beverage factory generates substantial wastewater during production. This effluent contains high concentrations of oils and sugars, along with significant suspended solids (SS) and organic pollutants.

Treatment Process:

The facility employs the following treatment train:

Bar Screen → Equalization Tank → Coagulation-Sedimentation → Hydrolytic Acidification → Aerobic Biological Treatment → MBR (Membrane Bioreactor) → Advanced Treatment

1. Bar Screen: Removes large suspended solids.

2. Equalization Tank: Stabilizes water quality and flow rate.

3. Coagulation-Sedimentation: Eliminates suspended solids and partial organic matter through chemical flocculation.

4. Hydrolytic Acidification: Breaks down complex organic compounds into simpler biodegradable molecules.

5. Aerobic Biological Treatment: Uses microorganisms to further degrade organic pollutants.

6. MBR (Membrane Bioreactor): Combines biological treatment with membrane filtration to remove residual SS and dissolved organics.

7. Advanced Treatment: Implements activated carbon adsorption to eliminate trace contaminants and odors.

Treatment Effectiveness:

The final effluent meets China’s National Discharge Standards, allowing:

- Safe discharge into natural water bodies

- Reuse in production processes (e.g., equipment cleaning, cooling systems)