Technological process and equipment for treating municipal sludge with earthworms

Abstract

The invention provides a technological process for treating municipal sludge with earthworms. The technological process comprises the following steps: flattening and inoculating, wherein adding an attractant into sludge, conveying the sludge to a conveyor belt in a treatment chamber, flattening the sludge with the flattening thickness of 5-10cm, and inoculating earthworms; earthworm treatment, wherein keeping the temperature of the treatment chamber to be 15-25 DEG C, shading and ventilating, and treating earthworms for 2-7 days; sludge conveying, wherein conveying the sludge treated by earthworms from the treatment chamber to an adjacent drying chamber by utilizing a conveying belt; heating dispelling, wherein a heating device at the bottom of the drying chamber is used for heating the sludge, the temperature is controlled to be 40 DEG C or lower, heating is conducted for 1-2 days, earthworms are dispelled with strong light into the treatment chamber for treatment of flattened sludgein the treatment chamber of a next time of conveying; reducing water content, wherein, continuous heating drying of sludge is carried out until water content is lower than 60% and the temperature is lower than 30 DEG C, and heating and drying are conducted for 2-7 days. On the other hand, the invention provides equipment for treating municipal sludge with earthworms, the earthworms are automatically recycled, the process of manually separating the earthworms is reduced, and the efficiency of treating sludge with earthworms is improved.

Description

technical field [0001] The invention relates to the field of agricultural waste treatment, in particular to a technological process and equipment for earthworm treatment of municipal sludge. Background technique [0002] Now the sewage treatment plant produces a large amount of sludge every day. The sludge of the sewage treatment plant is the sedimentary material and the scum on the surface of the sewage produced during the purification process of urban domestic sewage and industrial wastewater. It is a solid-liquid mixture. There is no external force. Under the action, the solid-liquid ratio is relatively stable, and the water content can reach more than 95%. After dehydration, the water content is 70-80%. According to the process of sewage treatment, sludge can be divided into primary sedimentation sludge, humic sludge, remaining activated sludge and digested sludge. Untreated sludge entering the environment will directly cause secondary pollution to water bodies and the ...

AI Technical Summary

Problems solved by technology

[0004] Among these methods, surface disposal is being gradually discontinued due to the prohibition of current environmental protection regulations; sanitary landfill is difficult to continue due to pressures such as shortage of land resources, secondary pollution, and residents' opposition; sea disposal will pollute the ocean and have a negative impact on the ocean. Ecosystems and human food chains pose a threat, which has been explicitly prohibited by international conventions; using incineration to treat municipal sludge will consume a lot of energy, and the incineration process will inevitably produce highly stable and highly toxic substances such as dioxins. Secondary pollution to the environment; sludge high-temperature composting technology itself generates a certain amount of heat, and the high temperature lasts for a long time. It achieves a higher degree of humification and improves effective nutrients, but the composting time is long, the area is large, and the operability is not strong, which is conducive to the breeding of diseases and insect pests

[0005] Using urban sludge as farmland fertilizer will directly cause serious environmental pollution. Even if urban sludge is treated by composting, although it can reduce the hazards of various pathogenic bacteria, insect eggs and other biological substances, it still cannot eliminate pollution such as heavy metals. hazards

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