Deep slag removing method for biogas slurry with high solid content

Abstract

The invention discloses a deep slag removing method for biogas slurry with high solid content, and belongs to the field of environment protection. The deep slag removing method includes: cultivating and acclimating compound microorganisms; applying the acclimated compound microorganisms to condition fresh biogas slurry with high solid content; subjecting the conditioned biogas slurry to solid-liquid separation through deep slag removing equipment so as to realize deep slag removing. The deep slag removing method for the biogas slurry with high solid content has the advantages that the difficulty in treatment of the biogas slurry with high solid content is solved, extracellular polymeric substances among particles of the biogas slurry can be peeled off by means of a microorganism method, inert pollutants are enabled to be destabilized, deep slag removal and biogas slurry pollution load reduction are realized by a mechanical dehydration technology, and then the biogas slurry can be conveniently subjected to subsequent simple biochemical treatment before standardized discharging.

Description

technical field [0001] The invention belongs to the field of environmental protection, and more specifically relates to a deep slag removal method for biogas liquid with high solid content. Background technique [0002] With the rapid development of my country's economy, various types of organic wastewater with high concentration and high solid content are produced, such as large-scale livestock and poultry breeding wastewater produced by large-scale breeding, and wastewater produced by kitchen waste treatment. Usually, high-concentration organic wastewater is first processed by anaerobic digestion to produce biogas. The biogas slurry produced is rich in nutrients such as nitrogen, phosphorus, and potassium and trace elements beneficial to plant growth and development. Therefore, biogas slurry has been widely used as an organic fertilizer. agriculture and forestry. However, due to the strong seasonality of agricultural and forestry production, the demand for fertilizers als...

AI Technical Summary

Problems solved by technology

A lot of research has been done on the treatment and resource utilization of biogas slurry with high solid content at home and abroad. Traditional treatment processes often use chemical, physical, and biological methods to remove nutrients in biogas slurry, such as A / O process, SBR process, and RAT process. Or its multiple combined processes, with complex treatment process, long cycle, high cost, difficult to meet the discharge standards, and the nutrients in the biogas slurry cannot be effectively utilized

For example, the existing technology with the publication number CN 105692962A realizes biogas slurry concentration and standard discharge through secondary biogas production, flocculation sedimentation, fine filtration, ultrafiltration, reverse osmosis and other process steps, but the hydraulic retention time needs 5 to 15 days, and The use of membrane treatment components requires high solid content in the feed water, which is easy to clog and has the disadvantages of high operating costs.

Invention patent CN104785012A uses multi-stage filtration and sedimentation to remove pollutants in the biogas slurry, but the process is cumbersome, the impact resistance is poor, and the effluent quality is difficult to meet the discharge standards stably

[0006] Biogas slurry with high solid content is difficult to treat and meet discharge standards. The main reason is that after anaerobic digestion, the alkalinity of the biogas slurry increases, the buffering property of pH increases, the content of extracellular polymers increases, and the particle size becomes finer. Pollutants such as COD and ammonia nitrogen are inert. Morphology exists, and traditional solid-liquid separation methods cannot be used for good separation to achieve the purpose of removing pollutants, resulting in a relatively long follow-up biochemical treatment cycle, complicated technical process routes, and ultimately making it difficult to meet discharge standards

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