Municipal sludge can be roughly divided according to its source: sewage sludge mainly refers to the sludge from sewage treatment plant; Sludge in pipe network refers to sludge from drainage collection system; River lake sludge refers to the deposited sludge from rivers, lakes, reservoirs, ditches and canals. If the sludge is not treated in time or correctly, it will cause serious environmental pollution. The emergence of municipal sludge dryer solves this problem. The municipal sludge dryer uses heat energy to send the dewatered sludge into the dryer and contact with hot air to dry the sludge.
"Four changes" after drying sludge by municipal sludge dryer:
(1) Reduction: sludge from the original high water content, large volume into small water content, small volume, easy to store, transport and facilitate the next step of utilization.
(2) Stabilization: the content of organic matter in the sludge before drying is very high, which is easy to corrupt and produce stench. After drying, some organic matter which is easy to corrupt is decomposed and dried, so it is not easy to corrupt, and the odor is greatly reduced, which is convenient for transportation and disposal.
(3) Harmless: before drying, the sludge has high water content and contains a large number of pathogenic bacteria, parasitic eggs and viruses, which is easy to cause large-scale spread of infectious diseases. After drying, pathogenic bacteria and parasite eggs in the sludge are killed in the drying process, so as to achieve the harmless and sanitary sludge.
(4) Recycling: municipal sludge dryer drying sludge at the same time to change harm into benefit, comprehensive utilization, environmental protection purposes. The sludge is rich in nitrogen, phosphorus and potassium. The dried sludge can be used as agricultural organic fertilizer; The sludge without pollution after drying can be landfilled; The dried sludge can be incinerated; The municipal sludge after drying is mixed with fly ash in a certain proportion to make building materials.