Features of Subsurface Sewage Treatment Facilities

1. Buried below ground level, the surface above the equipment can be used for landscaping or other purposes, demonstrating strong environmental adaptability. It prevents freezing in winter and flooding in summer; in northern regions, it requires deeper burial and insulation treatment.

2. The secondary biological contact oxidation process employs plug flow biological contact oxidation, which offers superior treatment efficiency compared to complete mixing or two-stage serial complete mixing biological contact oxidation ponds. It also features a smaller volume than the activated sludge pond, strong adaptability to water quality, excellent resistance to shock loads, stable effluent water quality, and prevents sludge bulking. The pond utilizes new elastic three-dimensional packing material, which has a larger specific surface area, facilitating easy microbial attachment and detachment. Under the same organic load conditions, it achieves a high removal rate of organic matter and enhances the solubility of oxygen in water.

3. The biochemical pool employs the biological contact oxidation method, featuring a low volume load of filling material. Microorganisms are in their own oxidation stage, resulting in minimal sludge production. Sludge is to be discharged once every three months (90 days) or more, either by pumping with a manure truck or by dewatering into sludge bricks for external transport.