Method for preparing carbon-based organic fertilizer from biogas slurry

Abstract

The invention provides a method for preparing carbon-based organic fertilizer from biogas slurry. The method comprises the following steps of using corn straws and charcoal as raw materials for preparing a mixed filter material; soaking the mixed filter material into biogas slurry before solid-liquid separation; after the adsorption saturation of the filter material, performing filtering to obtain a solid filter material adsorbing the biogas slurry; performing fermentation, sieving, drying and crushing to obtain the carbon-based organic fertilizer. The method has the advantages that the harmless treatment and resource utilization of two kinds of organic waste materials of stalks and biogas slurry can be realized; the biogas slurry is the biogas slurry before solid-liquid separation; the operation cost of biogas engineering on the solid-liquid separation of the fermentation products can be reduced; the crushed stalks and charcoal are used as adsorption filtering materials; the nutrition elements such as nitrogen and phosphorus in the biogas slurry can be effectively filtered and adsorbed; the additional addition of the nitrogen source of the subsequent aerobic fermentation is avoided; the charcoal can realize the foul smell substance discharge reduction in the compost process; meanwhile, the humification of the organic fertilizer compost process can be promoted; the fertilizer quality is improved; the goal of producing the carbon-based organic fertilizer is achieved.

Description

technical field [0001] The invention belongs to the technical field of biogas slurry treatment and resource utilization, and in particular relates to a method for preparing carbon-based organic fertilizer by using biogas slurry. Background technique [0002] With the rapid development of large-scale farming in my country, the discharge of livestock and poultry manure has increased sharply. The use of biogas projects to treat livestock and poultry manure is an important way to reduce environmental pollution and alleviate rural energy shortages. However, the operation of biogas projects will also produce a large amount of biogas slurry. If the biogas slurry cannot be effectively treated, random discharge will cause serious secondary pollution. If it is treated as wastewater, high operating costs will be incurred, which seriously restricts the development of the biogas engineering industry. Biogas slurry is generally rich in nutrients such as nitrogen, phosphorus, and potassiu...

AI Technical Summary

Problems solved by technology

Although this method is simple and low in cost, it faces many obstacles in its application in my country, such as insufficient land absorption capacity, seasonal and quantitative fertilizer use for crops, high transportation costs, and lower fertilizer efficiency and fertilization convenience than chemical fertilizers. , easy to pollute the water environment, etc.

The second is to produce multifunctional liquid compound fertilizers through concentration methods (membrane concentration, low-temperature evaporation, etc.) or adding nutrients (humic acid, inorganic elements, etc.). Although this method has a high degree of commercialization, it is technically difficult and expensive.

[0005] In summary, although there is a certain degree of research on the use of straw to absorb biogas slurry for the production of organic fertilizers, there are generally problems such as insufficient resource utilization of nutrients in biogas slurry and low quality of compost products.

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