What are the disposal methods for sludge?

1. Sludge thickening

The sludge produced by sewage treatment plants has a water content of up to 99%, and needs to be thickened before subsequent disposal of the sludge. The water content of sludge after thickening is about 95%.

2, sludge dewatering and drying

The sludge with 95% water content is high, which is not convenient for the later disposal of sludge. So it is necessary to carry out sludge mechanical dewatering or sludge drying treatment. Sludge mechanical dewatering equipment has stacked screw dewatering machine, plate and frame filter press, etc., which can dewater sludge to 80%-85%. Sludge drying equipment adopts dehumidification heat pump drying technology and low temperature waste heat drying technology, which can dry sludge to 10%.

Sludge drying

3, sludge disposal methods

(1) sanitary landfill

This disposal method is simple, easy to implement, low cost, and the sludge does not require a high degree of dewatering, and adaptability. The gas produced by the landfill is mainly methane, which can cause explosion and combustion if proper measures are not taken.

(2) land use

Sludge land use has the advantages of less investment, low energy consumption, low operating costs, the organic part can be converted into soil conditioner components, etc. It is a disposal method with more development potential.

(3) incineration

Sludge drying and incineration is a more common disposal method. It can make all the organic matter carbonized, kill pathogens, can reduce the volume of sludge to a greater extent; but its disadvantage lies in the large investment in treatment facilities, high treatment costs, high equipment maintenance costs, and the production of strong carcinogenic substances dioxin.

(4) Sludge composting

An important aspect of sludge composting for agricultural use, it is the use of microorganisms in the sludge fermentation process.