Why to dry sludge and the difficulties of sludge drying

According to statistics, sludge drying treatment plays an important role in the sludge treatment process on the market. Today, I'm going to talk about two major issues of sludge treatment.

1、 Why to dry sludge

Sludge contains a lot of water and organic matter, which is easy to rot and stink. Meanwhile, the sludge also contains heavy metals, pathogens, pathogens and other harmful substances. Sludge drying has achieved the national goal of sludge treatment and disposal: "reduction, harmless, stable and resource-based". The advantages are as follows:

1) Sludge drying can reduce the moisture content of sludge, reduce the volume of sludge, and facilitate the subsequent transportation and storage of sludge.

2) Most of the domestic sludge treatment is landfill. Sludge drying can not only reduce the volume, but also kill the harmful bacteria in the sludge, save space for sludge landfill, and avoid the pollution of sludge to the environment.

3)The dried sludge can be used as fertilizer, building materials and energy.

2、 What is the difficulty of sludge drying?

In the process of sludge drying treatment, mechanical dewatering can only remove the free water in the sludge and part of the gap water between the particles, while the water with strong binding force between the capillary water and the sludge particles needs to use the equipment of sludge drying machine, use high-temperature technology to destroy the combined water in the sludge cells, and realize the deep sludge dewatering sludge drying machine needs energy in the drying process (coal , oil, natural gas, etc.) fuel produces heat and high treatment cost. At the same time, due to high-temperature drying, odor or toxic gas and dust are easy to be generated in the drying process, which has the risk of dust explosion and other problems. Odor or toxic gas and dust need special treatment to meet the national emission standards before they can be discharged. Because the investment and operation cost of sludge dryer are generally high, which also leads to high requirements and conditions for the construction of sludge drying project, and limited area for popularization and application.

Environmental protection enterprises should continue to innovate in science and technology, develop new drying technologies and new energy, integrate these new technologies into the field of sludge drying, and improve sludge production efficiency.