Biogas slurry concentration method based on membrane separation

Abstract

The invention relates to the technical field of biogas slurry treatment, in particular to a biogas slurry concentration method based on membrane separation. The method mainly comprises the following steps of biogas slurry pretreatment, ultrafiltration membrane system circulation treatment, reverse osmosis membrane system circulation treatment and the like, wherein physical filtration modes such asa plate-and-frame filter press, a fiber bundle filter, a bag filter, a security filter and the like are sequentially adopted in the biogas slurry treatment process, no chemical agent is added in theprocess, so that concentrated biogas slurry is not interfered by chemical agents, and the problem that an ultrafiltration membrane system is easy to block is solved. In addition, concentrated solutionobtained by an ultrafiltration membrane system and a reverse osmosis concentration system is subjected to repeated circulation treatment to obtain the concentrated solution meeting the standard, andmeanwhile, permeate liquid obtained by the ultrafiltration membrane system and the reverse osmosis concentration system is used for backwashing and chemical cleaning, so that the utilization rate of the biogas slurry is improved, and a large amount of fresh water resources are saved, thereby greatly improving the economic and environmental benefits of the biogas slurry fermentation engineering.

Description

technical field [0001] The invention belongs to the technical field of biogas slurry treatment, in particular to a biogas slurry concentration method based on membrane separation. Background technique [0002] As an excellent organic fertilizer, biogas slurry can replace or partially replace chemical fertilizers on the basis of ensuring high crop yield and high quality, and can be used as base fertilizer, topdressing fertilizer or foliar fertilizer. A large number of tests have proved that biogas slurry is a high-quality, full-effect organic fertilizer. However, due to the low nutrient content of biogas slurry, more than 95% of which is water, it has been used for agricultural production and has not been commercially produced so far. With the development of membrane technology, biogas slurry membrane concentration technology will also usher in development opportunities. [0003] This process aims to explore ways to increase the synergistic value of biogas slurry, utilize b...

AI Technical Summary

Problems solved by technology

However, the current biogas slurry concentration process has problems such as high energy consumption, complicated equipment, large amount of chemical agents added, and easy clogging of the membrane, resulting in short service life of the membrane and high concentration cost.

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