Urban domestic sludge treatment process

Abstract

The invention discloses an urban domestic sludge treatment process.The process includes the following steps of 1 preparation of dewatered sludge, wherein sludge which is concentrated and dewatered by an urban sewage treatment plant is adopted; 2, conditioning of sludge, the dewatered sludge is conveyed to a slurry regulating pool, a chemical conditioning agent is added, and the mixture is stirred and mixed to be uniform through a stirrer in the regulating pool; 3, slurry radiation treatment, wherein slurry obtained after chemical conditioning is conveyed to a radiation workshop through a conveyor belt for radiation treatment; 4, slurry low-temperature pyrohydrolysis; slurry obtained after radiation treatment is beaten into a reaction kettle through a slurry conveying pump, a reaction kettle keeps closed in the work period, after slurry enters the reaction kettle, the temperature is raised continuously in the continuous stirring process, when the temperature is raised to 85-95 DEG C, timing is started, and the temperature is maintained at 90 + / -5 DEG C for 30-35 minutes; 5, slurry obtained after low-temperature pyrohydrolysis can be directly dewatered through a membrane filter press, the moisture content is lowered to 60% or below, the number of fecal coliform groups is smaller than or equal to 100 / g (mL), the slurry obtained after low-temperature pyrohydrolysis can also be combined with anaerobic digestion which has been developed and matured for stabilizing treatment, and methane gas utilization is achieved.

Description

technical field [0001] The invention relates to a process for treating urban domestic sludge, in particular to a process for treating sludge by using electron irradiation technology, and belongs to the technical field of environmental protection. Background technique [0002] With the promulgation of the new environmental protection law and the implementation of the "Water Ten Measures", people gradually focus on sludge treatment. At present, the sludge treatment technologies mainly include sludge thickening, sludge dehydration, sludge drying and sludge stabilization. Sludge drying requires a lot of heat sources, and it is only economical in places with direct heat sources such as thermal power plants and cement plants. At the same time, because sludge contains a large amount of extracellular polymers, which inhibit sludge cracking and limit sludge dehydration and stabilization treatment, how to improve the sludge cracking rate has become a limiting factor for sludge treatm...

AI Technical Summary

Problems solved by technology

High-temperature thermal hydrolysis requires high temperature and high pressure (temperature at 160-180°C, pressure at 2.8-8.0bar), which requires high equipment and devices. It is a process with high cost and high energy consumption, and there are also huge potential safety hazards

Maillard reaction will also occur in the process of high-temperature thermal hydrolysis of sludge, resulting in refractory substances, brown or even black macromolecular substances, and secondary pollution problems