Nitrogen resource heat-extraction recovery method

Abstract

The invention discloses a nitrogen resource heat-extraction recovery method. Through a pretreatment unit, an analytical unit, a deamination unit, an ammonia absorption unit and a crystallization dewatering unit which are sequentially connected, ammonia nitrogen in a liquid phase is transferred to a vapor phase through a physical method, then by additionally adding CO2, the ammonia nitrogen and ammonia nitrogen in the vapor phase generate a chemical reaction in the liquid phase to generate an ammonium bicarbonate solution, the ammonium bicarbonate solution separates crystals out after supersaturation, and solid ammonium bicarbonate is obtained by centrifugal dewatering. According to the nitrogen resource heat-extraction recovery method, nitrogen resources in leachate of refuse landfills andkitchen sludge anaerobic fermentation biogas liquid are recovered, meanwhile, engineering investment and the operation cost of a subsequent sewage treatment system are greatly lowered, and the goalsof energy saving and consumption reduction are achieved. The nitrogen resource heat-extraction recovery method is also suitable for recovery of nitrogen resources in other types of high-ammonia-nitrogen wastewater in the coal chemical industry.

Description

technical field [0001] The invention relates to the technical field of treatment of landfill leachate and kitchen sludge anaerobic fermentation biogas slurry, in particular to a method for thermal extraction and recovery of nitrogen resources. Background technique [0002] Landfill disposal of domestic waste in my country began in the 1980s and 1990s, and developed from simple landfill to standardized landfill. At present, about 60% of domestic waste in my country is disposed of in sanitary landfills, and landfills will inevitably cause secondary pollution of leachate. Ammonia nitrogen is a long-term pollutant in landfill leachate, and with the increase of landfill time, the concentration of ammonia nitrogen gradually increases, and the concentration of ammonia nitrogen in old leachate with landfill time of more than 10 years can be as high as 3000mg / L or more. With the increase of landfill use time and the development of waste incineration power generation in the past 10 y...

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Problems solved by technology

High concentration of ammonia nitrogen and low C / N ratio have brought great difficulties to the standard treatment of leachate and kitchen sludge anaerobic fermentation biogas slurry. Membrane bioreactors are used to treat landfills with imbalanced C / N ratios. For old leachate or kitchen sludge anaerobic fermentation biogas slurry, the cost of adding carbon sources often accounts for more than 50% of the operating cost, and the system has poor ability to resist water volume and water quality shock loads, and the effluent water quality is unstable

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