A system for producing ammonia from urea with ejected steam as an auxiliary heat source

Abstract

The invention relates to a urea ammonia production system using steam injection as an auxiliary heat source, which relates to the technical field of industrial waste gas purification, environmental protection and energy, in particular to a urea ammonia production system using steam injection as an auxiliary heat source, including an injection steam auxiliary heating system and urea A pyrolysis reaction system, wherein the ejected steam auxiliary heating system is connected to the urea pyrolysis reaction system through a steam-air heat exchanger. In the present invention, urea is pyrolyzed by auxiliary heating of dilution air through a steam injection heat pump. Compared with other heating methods, the method of the present invention injects low-grade low-temperature and low-pressure steam through high-grade high-temperature and high-pressure steam, effectively reducing the cold end of the system. At the same time, it reduces the electric heating power required for urea pyrolysis. It has good safety, moderate operation and investment costs, and has a good application prospect.

Description

technical field [0001] The invention relates to the technical fields of industrial waste gas purification, environmental protection and energy, and in particular to a urea ammonia production system using ejected steam as an auxiliary heat source. Background technique [0002] my country's energy endowment determines that thermal power will dominate in the short and long term. Thermal power generation mainly uses gas or coal to heat steam to drive steam turbines to generate power. The combustion process will produce harmful gas pollutants such as nitrogen oxides and sulfur dioxide. The removal of nitrogen oxides is mainly through the oxidation of nitrogen oxides in the ammonia and flue gas in the SCR reactor under the catalytic action of the catalyst. Reduction reaction to achieve the purpose of removing nitrogen oxides. The ammonia gas required in this method can be mainly obtained by methods such as liquid ammonia evaporation, urea hydrolysis, pyrolysis and other decompos...

AI Technical Summary

Problems solved by technology

Heating the dilution wind with an electric heater as the heat source for urea pyrolysis is currently a common method for thermal power units in China. The overall system is relatively simple, but this technology consumes a lot of energy and costs a lot.

Flue gas heating exchange has the problems of low heat exchange efficiency, huge heat exchange equipment, and high investment costs

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