Sludge treatment process

　　Welcome to those who need to call to order! A typical sludge treatment process consists of four stages of treatment or disposal. The first stage of sludge thickening, the main purpose is to make the initial sludge volume reduction, reduced the subsequent processing volume structures or equipment capacity; the second stage of sludge digestion, sludge organic matter decomposition; the third stage of sludge dehydrated sludge further volume reduction; fourth stage of sludge disposal, the use of sludge in some way will eventually be consumptive. Above stage filtrate or supernatant produced still contains large amounts of pollutants, and should therefore be sent back to the sewage treatment system. After more than a typical sludge treatment process, treated sludge can achieve the "four modernizations":

　　(1) Reduction: Due to the high water content of the sludge, bulky, and there was liquidity. After processing by the above process, the sludge volume was reduced by a factor of more than ten minutes, and converted into solid from liquid, easy to transport and consumptive.

　　(2) Stabilization: the high organic content of the sludge, easy to corruption and bad odors. After digestion stage treating the above process, part of the organic matter is decomposed transformed perishable, non-perishable, greatly reduce the stench, easy to transport and disposal.

　　(3) harmless: sludge, especially in primary sludge contains a large amount of pathogenic bacteria, viruses and parasite eggs, it could easily lead to large-scale spread of infectious diseases. After the above process of digestion stage, marriage can kill most of the eggs, pathogenic bacteria and viruses, greatly improve the health indicators of sludge.

　　(4) Resources: sludge is a resource, which contains a lot of calories, calorific value between 10000 ~ 15000kJ / kg (dry mud), higher than coal and coke. In addition, the sludge also contains a wealth of NPK, organic fertilizer with a higher fertilizer efficiency. Through the above process of digestion stage can be organic matter into biogas, which allows heat to use, but can also further improve its fertility. Sludge thickening processes are often used gravity concentration, flotation enrichment centrifuge enrichment, and so on. Sludge digestion can be divided into anaerobic digestion and aerobic digestion in two categories. Sludge dewatering can be divided into natural drying and mechanical dewatering two categories. Conventional mechanical dewatering processes are frame filter press dewatering, belt filter press dewatering, centrifugal dehydration. Many ways sludge disposal, mainly agriculture and forestry use, sanitary landfill, incineration and production of construction materials.