Integrated apparatus and method integrated in anaerobic digester to implement high-fiber material slurrying and scum shell breaking

Abstract

The invention discloses an integrated apparatus and method integrated in an anaerobic digester to implement high-fiber material slurrying and scum shell breaking, the apparatus is composed of a material conveying unit, a chamber unit mounted in the anaerobic digester and a slurry breaking unit, the slurry breaking unit is combined with the chamber unit that has special structural design, inner slurry is circulated during operation, multiple breaking treatments are carried out on high-fiber material, the size of the material discharged out of a material breaking chamber is limited through slurry breaking outlets distributed on the outer wall of the chamber, larger specific surface area for the material is provided, better contact of anaerobic microorganisms with the material is provided, and gas producing efficiency is improved; the integrated treatment implementing high-fiber material slurrying and scum shell breaking in the anaerobic digester enables reduced investment cost, simplified operation steps, lower energy consumption and promising market prospect.

Description

Technical field: [0001] The invention relates to the technical field of anaerobic digestion, in particular to an integrated device integrated in an anaerobic digestion reactor to realize pulping of high-fiber raw materials and removal of scum crusts and a method thereof. Background technique: [0002] Biomass such as straw, plant crops, and cow dung have high fiber content, and they are used as raw materials for anaerobic digestion. They generally need to be pretreated before entering the reactor. For straw, dry cow dung, etc. It also needs to be soaked for a long time, and the current mechanical pretreatment process and equipment have high energy consumption and poor effect. Biochemical pretreatment has problems such as long time and difficult control effect. It presents the characteristics of different sizes and lengths, heterogeneous phase, easy agglomeration, poor fluidity, and floating, which lead to problems such as uneven mixing with anaerobic sludge, long biochemical...

AI Technical Summary

Problems solved by technology

[0002] Biomass such as straw, plant crops, and cow dung have high fiber content, and they are used as raw materials for anaerobic digestion. They generally need to be pretreated before entering the reactor. For straw, dry cow dung, etc. It also needs to be soaked for a long time, and the current mechanical pretreatment process and equipment have high energy consumption and poor effect. Biochemical pretreatment has problems such as long time and difficult control effect. It presents the characteristics of different sizes and lengths, heterogeneous phase, easy agglomeration, poor fluidity, and floating, which lead to problems such as uneven mixing with anaerobic sludge, long biochemical reaction time, and the interaction between microorganisms and fiber substances in the digested feed liquid , form a biofilm on the surface of the raw material and gradually grow, and the biogas generated in the reactor adheres to the biofilm, which further promotes the floating of the raw material mass, accumulates on the upper layer of the reactor feed liquid, dehydrates and dries to form crusts and feed liquid stratification

[0003] The formation of raw material scum and crust layer has a great impact on the gas production efficiency and operation stability of the anaerobic digestion reactor: First, the floating crust of a large amount of high-fiber raw materials directly leads to the gas produced in the anaerobic digestion reactor Biogas cannot enter the gas storage tank through the crust layer, but can only gather in the lower part of the crust layer, increasing the buoyancy of the crust layer, and what’s more, the scum will block the discharge pipe and cause the reactor to burst; second, a large amount of biogas In the digestate, not only the partial pressure of biogas in the digestate is increased, but more CO in the biogas 2 Dissolved in the biogas slurry, the pH value of the biogas slurry will drop, affecting gas production; third, the crust prevents the raw material from fully contacting with the digestive juice and effectively decomposing, and the utilization rate of the raw material is less than 50%; fourth, the crust seriously affects the Solid, liquid and gas three-phase mass transfer, heat transfer and fluidity in the reactor are not conducive to gas production

[0004] At present, the method of stirring (mechanical stirring, hydraulic reflux stirring and biogas reflux stirring, etc.) is mainly used to solve the problem of anaerobic digestion of high-fiber raw materials. However, stirring can only cure the symptoms but not the root cause. The process can be temporarily relieved by disturbance, but it has not fundamentally solved the characteristics of the high-fiber raw materials in the reactor, which are of different sizes, heterogeneous, floating, and poor fluidity. Once the stirring is stopped, the high-fiber raw materials will be on the liquid level again. coalesce rapidly, forming crusts

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