Hydrolysis reactor automatic switching control method for ammonia production system

Abstract

The invention discloses a hydrolysis reactor automatic switching control method for an ammonia production system, which comprises the following steps: preheating a second reactor, and controlling thepressure of the second reactor to ensure that the pressure of the second reactor is stable to finish preheating preparation before switching of the second reactor; continuously adjusting the temperature of the second reactor to a first preset temperature value; controlling the urea flow according to a second preset flow value matched with the minimum ammonia demand; reducing switching fluctuations, meanwhile, when the temperature, the pressure and the urea flow of the second reactor are respectively in a preset deviation range, controlling the second reactor and the first reactor to increase and decrease the load in a preset mode until the urea flow of the first reactor meets the requirement, and finishing switching. The switching process is small in switching fluctuation, the pressure ofthe ammonia gas main pipe is effectively controlled to be stable, the ammonia gas yield meets the boiler requirement, and NOX overdischarge and ammonia gas leakage exceeding the standard of a boiler system are prevented; the production condition is continuous and stable, the workload of operators is reduced, the production efficiency is improved, and safe production is ensured.

Description

technical field [0001] The invention relates to the technical field of automatic control of a hydrolysis reaction system, in particular to an automatic switching control method of a hydrolysis reactor in an ammonia production system. Background technique [0002] As people's awareness of the safety of liquid ammonia is getting deeper and deeper, more and more countries have begun to use urea as a source of NH3. The United States and Europe have begun to use urea as an indirect denitrification reducing agent in large quantities since the 1990s. [0003] Urea and water can produce a mixture of ammonia and CO2 at a certain temperature and pressure, and this reaction is an endothermic reaction. The urea hydrolysis reaction can reach different chemical equilibrium states at different temperatures and pressures. Generally, this reaction is carried out at 150°C to 300°C. Under this temperature and normal pressure, the chemical reaction speed of urea hydrolysis is very slow, and it...

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Problems solved by technology

[0008] In view of this, the purpose of the present invention is to provide a method for automatic switching control of the hydrolysis reactor in the ammonia production system, to solve the problem that the existing hydrolysis reactor switching control is generally manually operated, and the stable production of ammonia cannot be controlled, resulting in excessive ammonia gas. row and so on

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