Urea ammonia production system with injected steam as auxiliary heat source

Abstract

The invention discloses a urea ammonia production system with injected steam as an auxiliary heat source and relates to the technical field of industrial waste gas purification environmental protection and energy. The invention particularly relates to the urea ammonia production system with the injected steam as the auxiliary heat source, the system comprises an injected steam auxiliary heating system and a urea pyrolytic reaction system, and the injected steam auxiliary heating system is connected with the urea pyrolytic reaction system through a steam-air heat exchanger. According to the system, urea is pyrolyzed by heating dilution air under the assistance of a steam injection type heat pump; compared with other heating methods, a method of the invention has the advantages that low-grade low-temperature and low-pressure steam is injected through high-grade high-temperature and high-pressure steam, the cold end loss of the system is effectively reduced, meanwhile, the electric heating power required by urea pyrolysis is reduced, and the method is good in safety, moderate in operation and investment cost and good in 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

Images