What is the Application of Sludge after Drying?
With the improvement of environmental protection awareness, the urban sewage treatment industry has been developing rapidly and the production of urban sludge is increasing day by day. The problem of sludge disposal and utilization is increasingly concerned by people. Sludge dryer is designed for dewatering and drying the urban sewage. What are the dried sludge used for?
Heavy Metal Recycling
In the wastewater treatment process of smelters, printed circuit board plants, electroplating plants and other enterprises, the sludge produced contains a large number of heavy metals (copper, nickel, gold, silver). If these metal components are discharged, it will be a major pollution. Considerable economic benefits can be obtained through smelting and extraction.
Incineration Power Generation
The calorific value of the dried sludge is about 1300 to 1500 kcal. Three tons of dried sludge can be equivalent to one ton of 4500 kcal coal. The dried sludge can be mixed with a certain proportion of coal for incineration, helping to reduce fuel consumption costs.
Used as Filler for Cement or Bricks
After being treated by dewatering equipment and sludge dryer, the sewage can be used as filler for making bricks or cement to reduce damage to land resources and environment. The cost of sludge bricks is low and the material is stable.
Organic Fertilizer
The nitrogen, phosphorus and potassium content of the sludge is higher than that of agricultural fertilizers such as pig manure, cow manure and chicken manure. And the organic matter content is as high as 70%. After drying, the water and harmful substances in the sludge have been removed, but the nutrients in the sludge are enriched and retained. The dried sludge is a good soil conditioner because of its organic composition containing crude protein. It can also be made into high quality organic fertilizer with agricultural fertilizer, which not only has better fertilization effect, but also can increase the nutrient elements of farmland and improve the soil structure.