Method for treating sludge by utilizing microbial flocculant and microbial wall breaking

Abstract

The invention provides a method for treating sludge by utilizing a microbial flocculant and microbial wall breaking. According to the method, residual sludge is subjected to biological modification with a microbial flocculant, the modified sludge is subjected to biological wall breaking with a microbial wall breaking flora and a heavy metal chelating flora, the content of heavy metals is reduced,and sludge is subjected to aerobic fermentation with a sludge fermentation flora and a biomass fermentation flora, such that the sludge is converted into organic humus. No chemical agent is added in the whole process, no energy is input into the sludge in the dehydration process, only a small amount of mechanical power is used during stacking and turning, the sludge is modified, heated and dried by purely utilizing the activity advantage of microorganisms, and finally reduction, harmlessness, stabilization and recycling of the sludge are achieved. According to the invention, a new method for treating and disposing residual sludge and industrial sludge with high organic matter content in municipal sewage plants is opened up, and the method provided by the invention has the advantages of lowequipment investment, simple operation, safety, no pollution, low energy consumption, and good economic and environmental benefits.

Description

technical field [0001] The invention relates to the technical field of sludge treatment and disposal, in particular to a method for treating and disposing sludge by using microbial flocculants and microbial wall breaking. Background technique [0002] According to statistics from the Ministry of Housing and Urban-Rural Development, as of the end of December 2017, my country has built a total of 5,027 sewage treatment plants, with a sewage treatment capacity of 188 million cubic meters per day, and an annual output of more than 50 million tons of sludge with a water content of 80%. The "Water Pollution Prevention and Control Action Plan" stipulates that the harmless treatment and disposal rate of urban sludge at the prefecture level and above should reach more than 90% by the end of 2020. The treatment and disposal of sludge is a worldwide problem. Traditional disposal methods include landfill, incineration, and agricultural utilization. These methods not only easily cause se...

AI Technical Summary

Problems solved by technology

The use of sludge in farmland can not only provide nutrients for crops, improve and fertilize the soil, but also treat a large amount of sludge. However, if sludge is continuously applied, there will be an increase in the accumulation of harmful substances such as heavy metals in the soil, which will increase the risk of soil pollution. risk

[0006] The technology and equipment of the incineration method are complex, energy-consuming, high-investment, and accompanied by air pollution problems; the landfill method is limited by land use, and the environment around the landfill will also deteriorate; throwing into the sea will pollute the ocean and have a negative impact on marine ecology. The system and the human food chain pose a threat, and international conventions have explicitly prohibited it; the use of urban sludge treated by composting for agriculture has the advantages of being economical, simple, and recyclable, but toxic and harmful pollutants such as heavy metals, pathogenic bacteria, and organic matter are in the soil. The accumulation of is a major obstacle in the use of sludge composting

In recent years, developed countries have carried out research on promoting anaerobic digestion process technology and sludge reduction technology, and improved the anaerobic digestion performance of sludge through various pretreatments (such as pyrolysis, hydrolysis acidification, alkali treatment, etc.). Sludge reduction treatment is carried out through measures such as ozone oxidation, ultrasonic technology, decoupling metabolism, and biological decomposition treatment. However, these technical methods have not been promoted due to their limitations.

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