Control system and method for urea hydrolysis reactor based on heat feedforward signal

Abstract

The urea hydrolysis reactor control method based on the heat feed-forward signal of the present invention comprises the following steps: 1) Obtain the transfer function from the load of the hydrolysis reactor to the amount of heating steam; 2) Generate a path of heating steam through the transfer function according to the load instruction of the hydrolysis reactor The amount signal is converted into the corresponding first heating steam door opening signal; 3) The second heating steam door opening signal is generated by the pressure deviation signal of the hydrolysis reactor through the door opening control function to obtain the deviation value; 4) The first heating steam regulating door opening signal is introduced into the heating steam regulating door opening automatic control logic as a feed-forward signal to determine the opening reference value; 5) The heating steam regulating door opening reference value and deviation value are weighted and output to obtain variable load Heating steam door opening signal under working conditions. The control system of the present invention includes a PLC controller for receiving the load instruction of the hydrolysis reactor, the pressure setting value and the measurement signal of the hydrolysis reactor.

Description

technical field [0001] The invention relates to a technology for producing ammonia by urea hydrolysis for denitrification in a thermal power plant, in particular to a control system and method for a urea hydrolysis reactor based on a heat feedforward signal. Background technique [0002] In recent years, domestic and foreign power generation companies have paid more and more attention to the potential dangers in the use of liquid ammonia. In some special areas and coal-fired power plants that are close to cities and residential areas, urea hydrolysis to ammonia has become an important method for the preparation of SCR denitrification and reduction. The recommended process for the agent. [0003] The urea hydrolysis ammonia production process has been gradually applied in the SCR denitrification reducing agent preparation section of thermal power plants. Ammonia production system; CN202430017U, a urea hydrolyzer applied to flue gas denitrification; CN201458752U; urea hydroly...

AI Technical Summary

Problems solved by technology

Due to the large size of the hydrolysis reactor and a large amount of high-temperature urea solution stored in the container, the working temperature of the hydrolysis reactor changes slowly under the action of thermal inertia, coupled with the heat conduction process of the heating steam, from the gas phase outlet valve action to the heating steam valve action The elapsed time will be very long, the response speed of the hydrolysis reactor to the load changing command is very slow, the steam valve moves frequently during the load changing process, and the heat waste is very serious

On the other hand, the shutdown process of the urea hydrolysis plant is relatively slow. When the ammonia gas supply needs to be cut off quickly due to a fault in the SCR area, how to control the emergency shutdown of the urea hydrolysis plant is also an urgent problem to be solved.

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