Biogas slurry decarbonization and deamination method and system

Abstract

The invention provides a biogas slurry decarbonization and deamination method and a biogas slurry decarbonization and deamination system. The method comprises the following steps: preheating to-be-treated biogas slurry and then feeding the biogas slurry to the upper part of a stripping tower; feeding stripping steam to the lower part of the stripping tower, carrying out countercurrent heat and mass transfer on the stripping steam and the preheated biogas slurry to be treated, and stripping carbon dioxide and ammonia gas in the preheated biogas slurry to be treated into a gas phase to obtain ammonia-carbon mixed steam; sending to-be-treated biogas slurry and / or a spraying agent to the upper part of the stripping tower, carrying out countercurrent heat and mass transfer on the to-be-treated biogas slurry and / or the spraying agent and the ammonia-carbon mixed steam, and removing ammonia gas from the ammonia-carbon mixed steam so as to enrich carbon dioxide at the top of the stripping tower and enrich ammonia gas in the middle of the stripping tower, the spraying agent comprises fresh water. According to the biogas slurry decarbonization and deamination method and system, efficient removal of ammonia carbon in the biogas slurry and recovery of carbon dioxide and ammonia gas can be achieved.

Description

technical field [0001] The invention relates to the technical field of biogas slurry treatment, in particular to a method and system for decarbonization and deamination of biogas slurry. Background technique [0002] After anaerobic fermentation of livestock manure, straw, kitchen waste, sludge, etc., biogas slurry containing high concentration of ammonia nitrogen will be produced. The direct discharge of biogas slurry with high concentration of ammonia nitrogen will cause the following problems: eutrophication of the water body, which will cause the deposition and transformation of pollutants, causing pollution to surface water and groundwater systems; rich and oxidized soil, causing algal blooms, leading to a decrease in dissolved oxygen, threatening The survival of aquatic organisms such as fish; the pollution of soil and water bodies will eventually act on human beings through the food chain, causing damage to human health; ammonia nitrogen is an important fertilizer res...

AI Technical Summary

Problems solved by technology

The direct discharge of biogas slurry with high concentration of ammonia nitrogen will cause the following problems: eutrophication of water body, which will cause the deposition and transformation of pollutants, causing pollution to surface water and groundwater systems; soil eutrophication will cause algae to multiply, lead to a decrease in dissolved oxygen, and threaten The survival of aquatic organisms such as fish; the pollution of soil and water bodies will eventually affect human beings through the food chain, causing damage to human health; ammonia nitrogen is an important fertilizer resource and chemical raw material, and direct discharge causes resource waste and poor economic benefits

[0003] In related technologies, the focus of biogas slurry treatment is to remove suspended solids and organic matter in biogas slurry, and there are few studies on ammonia nitrogen removal methods, and the removal effect is poor

The more commonly used method is to flash the biogas slurry. The flash evaporation method is a primary treatment, and the ammonia nitrogen removal effect is poor. The treated biogas slurry will still contain high ammonia nitrogen, which is difficult to meet the discharge requirements.

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