Method and equipment for dewatering municipal sludge with high dryness

Abstract

The invention relates to a method and equipment for dewatering municipal sludge with high dryness. The method comprises the following steps: putting to-be-treated sludge in a sludge treatment machine, and mixing and stirring with ferric sulfate or polymerized ferric sulfate; adding quick lime, and keeping on mixing and stirring to obtain treated sludge having neutral pH; and starting a feed pump of a filter press, pumping the treated sludge in the high-pressure diaphragm frame filter press, squeezing to obtain dewatered sludge cake, opening a filter plate, and delivering the dewatered sludge cake on a belt conveyer to the outside. The equipment comprises the sludge treatment machine, a sludge inlet pipe, the feed pump of the filter press, the high-pressure diaphragm frame filter press, a squeezing water pump, a squeezing water tank and the belt conveyor. According to the method, the dewatered sludge cake has a water content of less than 60 percent, has good ventilation after being ground, is suitable for growth and reproduction of microorganisms, can be directly subjected to aerobic fermentation, can be used for directly realizing reduction, harmlessness and resource of sludge, and is beneficial to sustained development.

Description

technical field [0001] The invention belongs to the technical field of sludge treatment, and relates to a high-dry dehydration method and equipment for municipal sludge. Background technique [0002] A large amount of sludge is produced in the process of municipal and industrial sewage treatment, most of which are directly used for agriculture without pretreatment or after simple treatment, and some are even piled up randomly. Pathogens in sludge pose potential threats to human health, and heavy metals and toxic and harmful organic substances pollute the surface Water and groundwater systems, the odor emitted by sludge pollutes the air, takes up a lot of land, has poor stability, and brings great harm to the environment. At present, the disposal methods of municipal sludge include aerobic composting, landfill, incineration, throwing into the sea, and making construction materials. [0003] Municipal sludge contains a large amount of organic matter, nitrogen and phosphorus a...

AI Technical Summary

Problems solved by technology

The most effective method of sludge modification is chemical modification, and the most classic, economical and effective modifiers are ferric chloride and lime; usually the dosage of ferric chloride and lime is 1 / 2 of the dry weight of sludge 15-50%, when ferric chloride is used as the conditioner, the chloride ion content in the water contained in the dewatered cake is very high, and the pH of the dehydrated cake is usually greater than 12, and subsequent aerobic fermentation cannot be carried out, and it cannot be used for greening and soil improvement. Not to mention agricultural use

[0006] In the past, people focused on how to reduce the moisture content of the mud cake, but no one has dehydrated and dehydrated the sludge.

Images