Combined anaerobic fermentation process for organic solid wastes

Abstract

The invention discloses a combined anaerobic fermentation method of organic solid wastes. The organic solid wastes used for the combined anaerobic fermentation include domestic wastes, excess sludge, feces, kitchen waste, straws, etc. The method comprises the following steps: carrying out different pre-processing processes to obtain organic materials with a granularity less than 5 mm; passing through a cutting pump, adjusting the C / N ratio, adjusting the water content, etc. to obtain a homogeneous fermentation substrate with a solid holdup of 2 to 10%; hydrolyzing and acidifying the fermentation substrate in the presence of a hydrolase; fermenting for a period of 15 to 25 days under the condition of stirring at a middle temperature of 32-38 DEG C to obtain biogas, which can be used for energy supply or output of a system; aging and desalting the biogas liquid to obtain a liquid humic acid fertilizer; and processing the biogas residues to a granular humic acid fertilizer. The fermentation substrate has proper C / N ratio to obviate feedback suppression of the substrate during the fermentation of a single material and simultaneously can enhance the hydrolysis effects of celluloses, lignin, hemicelluloses, etc. The method has the advantages of easy flow pattern control, low energy consumption, and no generation of sewages, and can obtain the high-quality biogas fluid and the high-quality granular humic acid fertilizer.

Description

technical field [0001] The invention belongs to the technical field of environmental protection for solid waste treatment, in particular to a method for resource utilization of organic solid waste combined with anaerobic fermentation. Background technique [0002] Organic solid waste mainly includes domestic garbage, feces, kitchen waste, residual sludge from municipal sewage treatment plants, straw, etc. With the development of society and economy and the increase of population, the output of organic solid waste increases at an average annual rate of 10%. Is biodegradable substances up to between 30-70%. Improper disposal of these solid wastes not only occupies land, pollutes rivers, destroys ecological landscapes, but also spreads diseases and affects environmental sanitation and residents' health. One of the major environmental issues to be addressed. The current treatment methods of organic waste include sanitary landfill, incineration, composting and anaerobic ferment...

AI Technical Summary

Problems solved by technology

If the facilities are built separately for various wastes, the investment will be large, and the scale effect will not be brought into play. Moreover, the inhibitory factors of a single material are obvious, and the material adjustment is difficult.

The biogas slurry and biogas residue produced during the fermentation of organic waste also have good utilization value. However, in the past, the biogas slurry was often used as sewage and needed to be treated to meet the discharge standards. The treatment is difficult and wastes liquid humus fertilizer.

The use of biogas residues can only obtain compound fertilizers through the ratio of nutrient elements, and does not have the function of water and fertilizer retention. Therefore, it cannot meet the actual needs

[0008] However, if organic solid waste is pretreated and combined with anaerobic fermentation, it can solve the problem of single fermentation material, poor homogeneity of fermentation substrate, low fermentation efficiency, and reduce the inhibition of fermentation products. At the same time, it can expand the scale of biogas utilization and improve Improve the quality of biogas slurry and residue, comprehensively solve the pollution of organic solid waste, and improve the level of resource utilization, harmlessness and reduction

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