CN-122006416-A - Waste heat utilization and regeneration system and method based on carbon capture system

Abstract

The invention provides a waste heat utilization and regeneration system and method based on a carbon trapping system, and relates to the technical field of carbon trapping and heat exchange, wherein the system comprises an absorption tower, a lean-rich liquid heat exchanger, a regeneration tower and a rich liquid storage tank which are sequentially connected; the system is also provided with a waste heat utilization device and a controller, the controller responds to a signal that the system enters an abnormal operation condition, the storage tank is controlled to receive the rich liquid, the waste heat utilization device and the driving unit are synchronously started, and the rich liquid is driven to flow through the regeneration tower through the circulation loop to complete regeneration. The invention can effectively utilize the system waste heat, realize the deep regeneration of the solvent under the abnormal operation condition, obviously shorten the restarting time of the system, improve the operation flexibility and be beneficial to reducing the degradation loss of the solvent.

Inventors

• Fan Zian
• LIU HANMING
• GAO SHIWANG
• ZHANG YUANXUE
• ZHAO XU
• WEI JINGXUAN
• YUAN XUMING
• YU LINBO
• ZHANG ZHENZHONG

Assignees

• 中国华能集团清洁能源技术研究院有限公司
• 华能洋浦热电有限公司

Dates

Publication Date

20260512

Application Date

20260324

Claims (10)

1. 1. The waste heat utilization and regeneration system based on the carbon trapping system is characterized by comprising an absorption tower, a lean-rich liquid heat exchanger, a regeneration tower and a rich liquid storage tank which are sequentially connected through related pipelines; The rich liquid storage tank is connected with the regeneration tower through a circulation loop, and the circulation loop comprises a driving unit; the system also comprises a waste heat utilization device for recovering and utilizing the residual heat of the system; And the controller is used for responding to a signal indicating that the system enters an abnormal operation condition, controlling the rich liquid storage tank to receive rich liquid, and starting the waste heat utilization device and the driving unit to drive the rich liquid in the storage tank to flow through the regeneration tower through the circulation loop for regeneration treatment.
2. 2. The system of claim 1, wherein the recirculation loop further comprises a rich liquor transfer line and a recirculation regeneration line, wherein an inlet of the rich liquor storage tank is in communication with the regeneration column via the rich liquor transfer line, and an outlet of the rich liquor storage tank is connected with the regeneration column via the recirculation regeneration line.
3. 3. The system of claim 2, wherein the waste heat utilization device comprises: The waste heat switching valve group is respectively communicated with the high-grade waste heat source and the medium-low grade waste heat source; The auxiliary heater is arranged on the circulating regeneration pipeline and is connected with the medium-low grade waste heat source.
4. 4. The system of claim 3, wherein a zoned heating coil is disposed within the rich liquid storage tank and is connected to the waste heat switch valve block.
5. 5. The system of claim 4 wherein the controller is further configured to obtain absorber type identification information for the rich liquid and adjust the output power of the zone heating coils to reduce the localized heating temperature when the type identification information corresponds to a pre-stored heat sensitive absorber.
6. 6. The system of claim 2 wherein a high efficiency mass transfer member is disposed within said regeneration column, and wherein the connection end of said recycle regeneration line to said regeneration column is an adjustable reflux port switchable to a different position on or in the top of the column.
7. 7. A method for waste heat utilization and regeneration based on a carbon capture system, applied to the system of any one of claims 1 to 6, comprising: responding to the abnormal operation condition of the system, and introducing rich liquid in the system into the rich liquid storage tank; And driving the rich liquid in the storage tank to flow through the regeneration tower for regeneration treatment through the circulation loop by utilizing the residual heat of the system.
8. 8. The method of claim 7, wherein utilizing residual heat from the system comprises heating the rich liquid in the storage tank with high grade waste heat and heating the rich liquid flowing in the circulation loop with medium grade waste heat.
9. 9. The method of claim 7, further comprising monitoring a CO 2 loading of the rich liquid and stopping the regeneration process when the CO 2 loading drops to a preset threshold.
10. 10. The method of claim 7, wherein the abnormal operating condition comprises a system shutdown or a load below a preset threshold.

Description

Waste heat utilization and regeneration system and method based on carbon capture system Technical Field The invention relates to the technical field of carbon capture and heat exchange, in particular to a waste heat utilization and regeneration system and method based on a carbon capture system. Background In the field of carbon capture, a chemical absorption method has become a main technical path for reducing emission of large-scale fixed sources CO 2 in coal-fired power plants and the like due to high maturity and strong adaptability. The process is usually based on a closed-loop circulation system formed by an absorption tower and a regeneration tower, and utilizes organic solvents such as amines and the like to selectively capture CO 2 in the flue gas, and realizes rich liquid desorption and lean liquid regeneration through thermal driving. To improve energy efficiency, existing systems commonly incorporate lean rich heat exchangers to recover sensible heat and employ reboilers to provide the heat energy required for desorption. Along with the improvement of the flexibility requirement of a double-carbon target propulsion and electric power system, the carbon trapping device increasingly faces unstable operation conditions such as frequent peak shaving, staged shutdown and the like. In this context, how to ensure the safety, economy and recoverability of the system during large fluctuations or interruptions in load has become a common challenge in engineering practice. However, the current technology system mainly performs an optimal design around steady state continuous operation, and lacks a systematic coping mechanism for energy dynamic management and solvent state regulation under abnormal working conditions. On one hand, sensible heat carried by the high Wen Fuye and related parts remained after equipment is stopped is gradually dissipated due to interruption of a heat source, a cascade utilization path is not formed, and the subsequent regeneration requirement is difficult to support, on the other hand, the rich solution is easy to generate irreversible thermal/oxidative degradation under a high-temperature stagnation state, so that the performance of a solvent is attenuated, the corrosion risk is increased, and the complete thermal balance and concentration gradient are required to be reestablished during restarting, so that the operation preparation time is remarkably prolonged. Although some researches try to introduce auxiliary heat sources or protective additives, a plurality of links (such as antioxidation storage or top gas waste heat recovery) are focused, and the technical problems of slow restarting and insufficient operation flexibility caused by waste of residual heat of a system and insufficient regeneration of a solvent exist. Disclosure of Invention The invention aims to provide a waste heat utilization and regeneration system and method based on a carbon capture system, which are used for solving the technical problems of slow restarting and insufficient operation flexibility caused by waste of system heat and insufficient solvent regeneration in the prior art. In a first aspect, an embodiment of the invention provides a waste heat utilization and regeneration system based on a carbon capture system, which comprises an absorption tower, a lean-rich liquid heat exchanger, a regeneration tower and a rich liquid storage tank which are sequentially connected through related pipelines, wherein the rich liquid storage tank and the regeneration tower are connected through a circulation loop, the circulation loop comprises a driving unit, the system further comprises a waste heat utilization device and a controller, the waste heat utilization device is used for recycling and utilizing residual heat of the system, the controller is used for responding to a signal indicating that the system enters an abnormal operation condition, the rich liquid storage tank is controlled to receive rich liquid, and the waste heat utilization device and the driving unit are started to drive the rich liquid in the storage tank to flow through the regeneration tower through the circulation loop for regeneration treatment. In some alternative implementations, the circulation loop further includes a rich liquid transfer pipeline and a circulation regeneration pipeline, the inlet of the rich liquid storage tank is communicated with the regeneration tower through the rich liquid transfer pipeline, and the outlet of the rich liquid storage tank is connected with the regeneration tower through the circulation regeneration pipeline. In some optional implementations, the waste heat utilization device comprises a waste heat switching valve group which is respectively communicated with the high-grade waste heat source and the medium-low grade waste heat source, and an auxiliary heater which is arranged on the circulating regeneration pipeline and is connected with the medium-low grade waste heat source. In some altern