Sewage sludge treatment device

Abstract

The invention relates to a sewage sludge treatment device. The sewage sludge treatment device comprises a concentrating device (1), a first heat exchanger (2), a second heat exchanger (3), an anaerobic digestion reactor (4), an aerobic digestion reactor (5) and a sludge dewatering device (6) which communicate with one another sequentially, wherein a medium inlet of a heat exchange tube 2a in the first heat exchanger communicates with a returned sludge outlet (5a) of the aerobic digestion reactor, an outlet of the heat exchange tube (2a) communicates with a returned sludge inlet (5b) of the aerobic digestion reactor, and an inlet of a distributing pipe (5e) of a spraying member (5d) at the upper part of an internal cavity of the aerobic digestion reactor (5) communicates with the outlet of the heat exchange tube (2a) in the first heat exchanger or is connected with and communicates with the middle section of a third tube element (9). The sewage sludge treatment device has the characteristics that the efficiency of removal of volatile suspended solids from sewage sludge can be increased, meanwhile, ammonia nitrogen is reduced, and the energy consumption is lowered.

Description

technical field [0001] The invention belongs to sludge treatment equipment, in particular to a treatment device for sludge generated during the operation of a sewage treatment site. Background technique [0002] In the process of urban and industrial sewage treatment, the process of removing inorganic or organic particulate matter and biodegradable compounds through sedimentation and filtration produces a large amount of sludge, including primary sedimentation tank sludge and secondary sedimentation tank sludge. In addition to precipitable organic and inorganic particulate matter, the sludge is mainly composed of bacterial cells and microbial residues that age and die when microorganisms oxidize and decompose organic matter in sewage. At present, the commonly used sewage sludge treatment technologies mainly include anaerobic digestion and aerobic digestion, among which anaerobic digestion is widely used. [0003] The current anaerobic digestion treatment mainly includes con...

AI Technical Summary

Problems solved by technology

Deficiencies: ①The removal rate of volatile suspended solids (VSS) is 40-45%, the removal rate is low, and the effect of sludge reduction is not obvious; ②The anaerobic digestion process will produce ammonia. Under anaerobic conditions, ammonia It cannot be nitrified, resulting in a high concentration of ammonia nitrogen in the filtrate produced by sludge dehydration, some as high as 1000-1500mg / l, which is not conducive to subsequent sewage treatment; ③Under anaerobic conditions, the phosphorus-accumulating bacteria in the sludge will be stored in the cells The polymerized phosphate in the sludge is released through hydrolysis, and forms ammonium magnesium phosphate (struvite) with calcium, magnesium ions and ammonia in the sludge, which is easy to form scaling in the sludge dewatering equipment, affecting the normal operation of the dehydration equipment

Deficiencies: ①The removal rate of volatile suspended solids (VSS) is 55-60%; ②During the aerobic digestion process, aerobic microorganisms decompose organic matter, and organic nitrogen will also be converted into NH 4 + , and the aerobic reaction is an exothermic reaction, so the higher temperature in the reactor will inhibit the growth of nitrifying bacteria and nitrosifying bacteria, and it is difficult to treat NH 4 + Carry out nitrification and nitrosation reactions, resulting in NH 4 + The accumulation of the sludge and the increase of the pH value, the increase of the pH value will cause certain toxicity to the system and affect the normal operation of the system; ③The sludge aerobic digestion process will produce a large amount of foam, which will affect the operation

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