CN-122006591-A - Urea hydrolysis system

CN122006591ACN 122006591 ACN122006591 ACN 122006591ACN-122006591-A

Abstract

The invention relates to the technical field of urea hydrolysis, and discloses a urea hydrolysis system, which comprises a drain tank hot water circulation heat preservation module, a closed loop circuit formed by a urea dissolving tank and the like, a bidirectional flow regulation and cavitation prevention assembly arranged between an inlet of a circulating pump and a buffer tank, a heating medium intelligent switching module, a gradient drain recycling management and control module, a drain recycling branch and a multi-parameter water quality closed loop monitoring unit, a steam condensation recycling strengthening module, a drain anti-scaling pretreatment module, a pipeline equipment scaling reduction module, a system emergency guarantee module, a drain water automatic guiding module and a system operation stability, energy conservation and economy improvement module, wherein the steam and drain heating self-adaptive switching is realized through temperature and flow cooperative control three-way valves, the steam consumption is reduced, the gradient drain recycling management and control module utilizes a drain recycling branch and a multi-parameter water quality closed loop monitoring unit, the drain gradient utilization is realized, the steam condensation recycling strengthening module captures steam by means of a steam condensation recycling device to reduce steam dissipation, and the drain anti-scaling pretreatment module is used for reducing pipeline equipment scaling, and the system emergency guarantee module is used for automatically guiding drain when water quality is abnormal.

Inventors

LI JINHONG
ZHANG WEIDONG
CUI SHENGDONG
DING CONG
LI ZHIQIANG

Assignees

华能嘉祥发电有限公司

Dates

Publication Date: 20260512
Application Date: 20260127

Claims (10)

1. A urea hydrolysis system, comprising: The drain tank hot water circulation heat preservation module is characterized in that a closed loop is formed by a urea dissolving tank, a urea solution storage tank, a urea hydrolyzer, a heating coil, a drain tank, a buffer tank and a circulating pump, a bidirectional flow regulation and cavitation prevention assembly is connected in series between an inlet of the circulating pump and the buffer tank, and the drain tank hot water forced circulation is driven by the circulating pump; The intelligent heating medium switching module is characterized in that temperature and flow cooperative control three-way valves are arranged at the inlet and the drainage outlet of the heating coil, the inlet is respectively connected with a steam pipeline and a drainage box hot water pipeline, and the outlet is in butt joint with the heating coil to realize self-adaptive switching of steam heating and drainage heating; the gradient drainage recycling management and control module is used for arranging a drainage recycling branch on the outlet branch of the circulating pump, integrating a multi-parameter water quality closed-loop monitoring unit, collecting water quality data in real time and matching different recycling scenes to realize drainage gradient utilization; the steam condensation recovery strengthening module is used for sealing and connecting a steam capturing condensation recovery device of the spiral condensation and noncondensable gas separation integrated component at the exhaust end of the drain tank, prolonging the retention time of steam and separating noncondensable gas; the hydrophobic anti-scaling pretreatment module is characterized in that a honeycomb flow guiding and magnetic descaling assembly is arranged in the buffer box to guide the uniform flow of the hydrophobic liquid and intercept and remove scale induced impurities; And an abnormal working condition backflow switching unit is arranged between the recycling branch and the drain tank, and is used for automatically guiding the drain tank to reduce the steam generation amount of the drain tank from the source when the water quality is abnormal.
2. The urea hydrolysis system according to claim 1, wherein the bidirectional flow regulating and cavitation preventing assembly comprises a flow sensor, an adjustable throttle valve and a cavitation preventing cavity, the flow sensor monitors the circulating flow in real time and feeds back the circulating flow to the adjustable throttle valve, and the cavitation preventing cavity inhibits cavitation at an inlet of the circulating pump through a negative pressure buffer structure.
3. A urea hydrolysis system according to claim 1, wherein the temperature and flow cooperative control three-way valve is in wired signal linkage with a temperature monitoring element of related equipment, and the valve opening proportion is dynamically adjusted by collecting real-time temperature and drainage circulation flow data of the solution in the equipment.
4. The urea hydrolysis system according to claim 1, wherein the multi-parameter water quality closed-loop monitoring unit integrates the functions of pH value and suspended matter content monitoring, is provided with a data storage and trend analysis sub-module in a matched mode, and early warns of potential exceeding risk by analyzing water quality change trend.
5. A urea hydrolysis system according to claim 1, wherein the spiral condensing channel of the spiral condensing and noncondensable gas separation integrated component adopts a tapered structure, the cross section of the spiral condensing channel gradually decreases from the inlet to the outlet, and the noncondensable gas separation area is provided with a light gas floating guide plate for guiding the separation of noncondensable gas.
6. The urea hydrolysis system according to claim 1, wherein the honeycomb flow guiding units of the honeycomb flow guiding and magnetic descaling assembly are made of corrosion-resistant high polymer materials, the internal flow guiding channels are arranged in a hexagonal shape, the magnetic descaling units are embedded into the honeycomb structure, and the arrangement state of scale ions in water is changed through the action of a strong magnetic field.
7. The urea hydrolysis system of claim 1, wherein the abnormal condition backflow switching unit comprises an emergency backflow valve, a flow monitor and a control module, the flow monitor monitors the flow change of the recycling branch in real time, and when the flow is lower than a preset range or the water quality monitoring unit sends out an exceeding signal, the control module immediately triggers the emergency backflow valve to open so as to guide the drain water back to the drain tank.
8. The urea hydrolysis system according to claim 1, wherein the heating coil is provided with a heat-insulating sheath and a heat-exchanging strengthening coating, the heat-insulating sheath is made of flame-retardant heat-insulating material, and the heat-exchanging strengthening coating is coated on the inner wall of the coil.
9. The urea hydrolysis system according to claim 1, wherein the temperature and flow cooperative control three-way valve is internally provided with a wear-resistant sealing valve seat and a flow balancing hole, the wear-resistant sealing valve seat is made of ceramic materials, and the flow balancing hole is used for balancing flow resistance of two heating media.
10. The urea hydrolysis system of claim 1, wherein the multi-parameter water quality closed loop monitoring unit and the system linkage control module establish a data interaction channel, water quality monitoring data are transmitted to the control module in real time, and the control module adjusts the rotation speed of the circulating pump and the opening degree of the recycling branch valve by combining the running state of the equipment, so that the dynamic matching of water quality, flow and equipment requirements is realized.

Description

Urea hydrolysis system Technical Field The invention relates to the technical field of urea hydrolysis, in particular to a urea hydrolysis system. Background The urea hydrolysis system is widely applied to the field of denitration, ammonia gas is generated by hydrolyzing urea solution, a reducing agent is provided for flue gas denitration reaction, and the running stability, energy conservation and economy of the urea hydrolysis system directly influence the overall efficiency of the denitration process. In industrial application, the urea hydrolysis process needs to maintain a specific temperature zone, relies on hot water circulation and steam heating to provide heat, and simultaneously accompanies a large amount of drainage, so that the problems of drainage recycling, system scaling prevention, steam generation prevention and the like are very important for long-term operation of the system. In the existing urea hydrolysis system, the drainage recycling branch is lack of a perfect abnormal condition backflow switching mechanism, and an accurate guide and return control structure is not arranged for water quality abnormality, and the drainage recycling branch is processed by means of simple water quality monitoring or manual intervention. This kind of structural design defect leads to when the hydrophobic quality of water appears unusual, can't in time leading back the hydrophobic case with unusual hydrophobic from the retrieval and utilization branch road, and unusual hydrophobic continuously gets into the retrieval and utilization link and not only can influence subsequent equipment operation, still can indirectly lead to the hydrophobic incasement operating mode unbalance, and then causes the phenomenon of steam bleeding, causes heat energy loss in a large number, influences system overall operation stability simultaneously. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a urea hydrolysis system to solve the problems that the working conditions in the hydrophobic tank are unbalanced, so that the phenomenon of steam generation is caused, a large amount of heat energy is lost, and the overall operation stability of the system is influenced. In order to achieve the above purpose, the invention provides a urea hydrolysis system, comprising: The drain tank hot water circulation heat preservation module is characterized in that a closed loop is formed by a urea dissolving tank, a urea solution storage tank, a urea hydrolyzer, a heating coil, a drain tank, a buffer tank and a circulating pump, a bidirectional flow regulation and cavitation prevention assembly is connected in series between an inlet of the circulating pump and the buffer tank, and the drain tank hot water forced circulation is driven by the circulating pump; The intelligent heating medium switching module is characterized in that temperature and flow cooperative control three-way valves are arranged at the inlet and the drainage outlet of the heating coil, the inlet is respectively connected with a steam pipeline and a drainage box hot water pipeline, and the outlet is in butt joint with the heating coil to realize self-adaptive switching of steam heating and drainage heating; the gradient drainage recycling management and control module is used for arranging a drainage recycling branch on the outlet branch of the circulating pump, integrating a multi-parameter water quality closed-loop monitoring unit, collecting water quality data in real time and matching different recycling scenes to realize drainage gradient utilization; the steam condensation recovery strengthening module is used for sealing and connecting a steam capturing condensation recovery device of the spiral condensation and noncondensable gas separation integrated component at the exhaust end of the drain tank, prolonging the retention time of steam and separating noncondensable gas; the hydrophobic anti-scaling pretreatment module is characterized in that a honeycomb flow guiding and magnetic descaling assembly is arranged in the buffer box to guide the uniform flow of the hydrophobic liquid and intercept and remove scale induced impurities; And an abnormal working condition backflow switching unit is arranged between the recycling branch and the drain tank, and is used for automatically guiding the drain tank to reduce the steam generation amount of the drain tank from the source when the water quality is abnormal. Preferably, the bidirectional flow regulating and cavitation preventing assembly comprises a flow sensor, an adjustable throttle valve and a cavitation preventing cavity, wherein the flow sensor monitors the circulating flow in real time and feeds back the circulating flow to the adjustable throttle valve, and the cavitation preventing cavity inhibits cavitation at an inlet of the circulating pump through a negative pressure buffer structure; The three components form closed loop linkage control, the flow sensor transmits moni