Method for improving anaerobic digestion performance of sludge and synchronously enlarging cultivation by functional bacteria

Abstract

The invention relates to a method for improving anaerobic digestion performance of sludge and synchronously enlarging cultivation by functional bacteria. The method comprises the following steps of: collecting and screening the functional bacteria; enlarging cultivation of the functional bacteria; preparing functional bacteria solution; inoculating the functional bacteria solution into an anaerobic digestion reactor containing sludge after carrying out anaerobic digestion for 10-15 days on the sludge, further carrying out anaerobic digestion on the sludge for 15-30 days, hydrolyzing protein which is difficult to degrade in the sludge into low molecular weight organic matters by the functional bacteria; hydrolyzing the low molecular weight organic matters to form methane by mathanogenic bacteria; and carrying out multiplication of bacteria cells by the functional bacteria, so as to finally obtain sludge digestion residue containing the methanogenic bacteria and the functional bacteria. Compared with the prior art, advantages enrichment and expansion of the functional bacteria are achieved by the method; the obtained sludge digestion residue contains target functional bacteria, and can be used as an inoculant to be applied to anaerobic digestion treatment of the sludge by circulating inoculation; and the anaerobic digestion efficiency of the sludge is lastingly improved, and the treatment cost is reduced.

Description

technical field [0001] The invention belongs to the fields of environmental protection and resource comprehensive utilization, and relates to a process for anaerobic digestion treatment of sludge, in particular to a method for improving the anaerobic digestion performance of sludge by using functional bacteria and simultaneously expanding cultivation. Background technique [0002] Sludge from urban sewage treatment plants is the main secondary pollutant produced by sewage treatment. It is estimated that the national dry sludge output will reach 7 million to 12 million tons per year during the 12th Five-Year Plan period. If such a huge amount of sludge is not properly disposed of, it will cause serious secondary pollution to the environment. Biological treatment of sludge includes aerobic treatment, fermentation and anaerobic digestion. Sludge anaerobic digestion is a sludge treatment process widely used at present. It refers to the degradation of carbohydrates, proteins, f...

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Problems solved by technology

[0006] It can be seen that the current biological bacteria pretreatment method is generally used for aerobic or facultative fermentation of sludge, and is rarely connected with anaerobic digestion of sludge; the biological bacteria used are aerobic or facultative bacteria, and it is difficult to Obtain a competitive advantage in the anaerobic environment of the sludge anaerobic digestion process, and the sludge anaerobic digestion reactor is easily replaced by the indigenous anaerobic bacteria in the reactor, which means that these biological bacteria can only be used for sludge Before anaerobic digestion, each feeding is a fresh bacterial agent that needs to be re-expanded and cultivated with a special medium, which greatly increases the cost of pretreatment; and this type of biological bacteria utilizes the relatively easily degradable organic matter in the sludge. However, it is difficult to strengthen the hydrolysis of a large amount of relatively refractory organic matter remaining in the late stage of sludge anaerobic digestion.

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