Method and device for treating residual sludges

Abstract

The invention provides a method and a device for treating residual sludges. The method for treating residual sludge comprises the steps of mixing the residual sludges and conditioners evenly, placing the mixture in a ventilation location for 7-16 d, artificially stirring once every 12-36 h, after mixing the residual sludges and a conditioner for 7-16 d, adding earthworms to form compost, waiting for 56 - 63 d to obtain an earthworm fecal sludge product. The earthworm fecal sludge product is applied in high efficient fertilizers or soil conditioners. By adding cow dung as conditioners, the adverse effects of residual sludge on the earthworms are alleviated, and the growth and reproduction of earthworm in the compost are improved, the earthworm biomass balance is ensured, the organic matter degradation ability of earthworm in the compost is enhanced, thus the composting efficiency is improved. The method and device for treating residual sludges provide an effective way for the resource utilization of sludges in towns and villages.

Description

technical field [0001] The invention belongs to the technical field of biological treatment, and in particular relates to a method for treating excess sludge and an excess sludge treatment device. Background technique [0002] During the "Thirteenth Five-Year Plan" period, my country will continue to strengthen the construction of domestic sewage treatment facilities in villages and towns, and the production of biological sludge will also continue to increase. Activated sludge method is currently the most widely used sewage biological treatment technology. The biggest disadvantage of this technology is that it produces a large amount of excess sludge. The excess sludge has high water content, high organic content, high microbial activity, and is easy to rot and smell Potential heavy metal and pathogenic microorganism hazards. If the excess sludge is not properly disposed of, it will pose a serious threat to land resources, water environment and sanitation environment in vil...

AI Technical Summary

Problems solved by technology

[0004] 1. The investment and operation costs of anaerobic digestion technology are high, and a large amount of sludge residue and digestive juice remain, which cannot achieve the final treatment purpose

[0005] 2. The aerobic digestion technology has a great influence on the temperature and cannot effectively kill the pathogenic bacteria in the sludge. The dehydration performance of the digested sludge is poor, and the long-term aeration leads to high energy consumption.

[0006] 3. The investment cost of aerobic composting technology is relatively high, and fixed fermentation tanks, stirring and ventilation equipment are required; a large amount of malodorous gas is produced during the process of microbial decomposition of organic matter; the loss of nitrogen is large, and the agricultural value of compost products is reduced

[0007] 4. In the sludge treatment system of earthworm composting, the residual sludge has high moisture content and low porosity, which can easily create an anaerobic environment and hinder the respiration of earthworms; the C / N ratio in the residual sludge is low, which may cause protein poisoning symptoms in earthworms ; Inorganic salts, heavy metals, pathogenic microorganisms, etc. contained in the remaining sludge do not use the growth and reproduction of earthworms; in terms of organic matter degradation and stability, the degradation rate of organic matter in traditional earthworm composting is low, and the stability of sludge needs to be improved; In the process of composting sludge, organic acids and ammonia gas that are toxic to earthworms will be produced, and these organic substances can cause earthworms to die in trace amounts

[0008] None of the above methods is an ideal biological treatment technology for excess sludge. However, compared with anaerobic digestion, aerobic digestion and aerobic composting, the above-mentioned shortcomings in the process of earthworm composting lead to limited function of earthworms and unsatisfactory compost stabilization effect. As a result, vermicomposting cannot be carried out efficiently for a long time

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