阅读说明：本技术 一种超临界二氧化碳透平干气密封失效保护装置及方法 (Supercritical carbon dioxide turbine dry gas seal failure protection device and method ) 是由 刘光旭 黄彦平 王俊峰 于 2020-05-20 设计创作，主要内容包括：本发明提供了一种超临界二氧化碳透平干气密封失效保护装置及方法,保护装置包括：气缸冷却结构,对透平气缸中干气密封附近区域的缸体进行冷却；二氧化碳保护单元,具有向气缸冷却结构提供二氧化碳冷却气的冷却支路,同时具有向透平轴承附近区域提供二氧化碳保护气的保护支路。方法将壁温超限与透平停机和引入二氧化碳冷却气启动联锁控制,通过外接二氧化碳冷却气对透平气缸中干气密封的附近区域缸体进行冷却；将泄漏压力超限与透平停机和引入二氧化碳保护气启动联锁控制,通过外接二氧化碳保护气对失效干气密封失效时的透平轴承进行喷气保护。本发明确保干气密封不被高温损坏,还可防止透平干气密封实现后泄漏的高温气体引燃轴承处的润滑油。(The invention provides a supercritical carbon dioxide turbine dry gas seal failure protection device and a supercritical carbon dioxide turbine dry gas seal failure protection method, wherein the protection device comprises the following components: the cylinder cooling structure is used for cooling the cylinder body in the area near the dry gas seal in the turbine cylinder; and a carbon dioxide protection unit having a cooling branch for supplying carbon dioxide cooling gas to the cylinder cooling structure and a protection branch for supplying carbon dioxide protection gas to the region near the turbine bearing. The method comprises the steps of performing interlocking control on wall temperature overrun, turbine shutdown and carbon dioxide cooling gas introduction, and cooling a cylinder body in the vicinity of a dry gas seal in a turbine cylinder through the external carbon dioxide cooling gas; and (3) carrying out interlocking control on the leakage pressure overrun, turbine shutdown and the start of introducing carbon dioxide protective gas, and carrying out air injection protection on the turbine bearing when the failure dry gas seal fails through the external carbon dioxide protective gas. The invention ensures that the dry gas seal is not damaged by high temperature, and can prevent the leaked high-temperature gas from igniting the lubricating oil at the bearing after the dry gas seal of the turbine is realized.)

1. A supercritical carbon dioxide turbine dry gas seal failure protection device, the protection device comprising:

the cylinder cooling structure is used for cooling the cylinder body in the area near the dry gas seal in the turbine cylinder;

and a carbon dioxide protection unit having a cooling branch for supplying carbon dioxide cooling gas to the cylinder cooling structure and a protection branch for supplying carbon dioxide protection gas to the region near the turbine bearing.

2. The supercritical carbon dioxide turbine dry gas seal failure protection device of claim 1 wherein the cooling branch comprises a carbon dioxide storage tank, a carbon dioxide pump, a heater and an electrically operated shutoff valve connected by piping, and an outlet of the cooling branch is connected to an air inlet of the cylinder cooling structure.

3. The supercritical carbon dioxide turbine dry gas seal failure protection device of claim 1 wherein the protection branch comprises a carbon dioxide storage tank and a pneumatic shut-off valve connected by a pipeline, the outlet of the protection branch being disposed in the region near the turbine bearing.

4. The supercritical carbon dioxide turbine dry gas seal failure protection device of claim 1 wherein the cooling branch is disposed in parallel with the protection branch and is connected to the same carbon dioxide storage tank.

5. The supercritical carbon dioxide turbine dry gas seal failure protection device of claim 1, wherein the protection device comprises a pressure transmitter for monitoring dry gas seal leakage pressure in real time, a temperature transmitter for monitoring wall temperature of a cylinder cooling structure in real time and a control unit, and the pressure transmitter and the temperature transmitter are electrically connected with the control unit.

6. The supercritical carbon dioxide turbine dry gas seal failure protection device according to claim 5, wherein when the detected temperature value of the temperature transmitter exceeds a limit, the control unit controls the turbine to stop and automatically switches on the cooling branch to introduce carbon dioxide cooling gas to cool the area near the dry gas seal in the turbine cylinder; when the detection pressure value of the pressure transmitter exceeds the limit, the control unit controls the turbine to stop and automatically switches on the protection branch to introduce carbon dioxide protection gas to perform jet protection on the area near the turbine bearing.

7. The supercritical carbon dioxide turbine dry gas seal failure protection apparatus of claim 1 wherein the cylinder cooling structure is disposed in the block in the area near the dry gas seal in the turbine cylinder in a spiral configuration, serpentine configuration or annular configuration.

8. A method for protecting the dry gas seal failure of a supercritical carbon dioxide turbine, which is characterized in that the dry gas seal failure protection device of the supercritical carbon dioxide turbine is used for protecting the failure of the dry gas seal failure protection device of any one of claims 1 to 7.

9. A supercritical carbon dioxide turbine dry gas seal failure protection method is characterized in that wall temperature overrun, turbine shutdown and carbon dioxide cooling gas introduction are controlled in an interlocking mode, and a cylinder body in the vicinity of a dry gas seal in a turbine cylinder is cooled through the external carbon dioxide cooling gas;

and (3) carrying out interlocking control on the leakage pressure overrun, turbine shutdown and the start of introducing carbon dioxide protective gas, and carrying out air injection protection on the turbine bearing when the failure dry gas seal fails through the external carbon dioxide protective gas.

10. The supercritical carbon dioxide turbine dry gas seal failure protection method of claim 9 wherein the cylinder wall temperature in the vicinity of the dry gas seal in the turbine cylinder is monitored in real time while the dry gas seal leakage pressure is monitored in real time.

Technical Field

The invention relates to the technical field of advanced turbine equipment, in particular to a supercritical carbon dioxide turbine dry gas seal failure protection device and method.

Background

The supercritical carbon dioxide power conversion technology has the technical advantages of system simplification, high efficiency, small volume, easy realization of module construction and the like, a supercritical carbon dioxide turbine is one of core equipment of the system, and the turbine is obviously different from a conventional steam turbine in that the operating working medium of the turbine is high-temperature high-pressure carbon dioxide and the outlet pressure is high.

The shaft end seal of the supercritical carbon dioxide turbine adopts dry gas seal, and the bearing adopts a sliding bearing, which is the technical scheme adopted by the supercritical carbon dioxide turbine at present. However, in the existing dry gas seal at the present stage, mainly aiming at medium and low temperature application scenes, the seal ring of the dry gas seal is usually made of rubber and cannot meet the requirement of the working condition with the temperature of more than 300 ℃, so the turbine cylinder needs to be provided with a cooling structure to reduce the temperature of the cylinder at the dry gas seal structure to be less than 300 ℃. When the turbine is stopped, the cooling structure of the turbine cylinder still needs to be continuously cooled, and if the cooling fails, the dry gas seal is damaged. In addition, the end face of the dry gas seal is abraded, external foreign matters fall into the dry gas seal, the dry gas seal is damaged due to cooling failure or other reasons, the end part of the turbine is sealed and fails, high-temperature and high-pressure carbon dioxide in the turbine is sprayed to the site, lubricating oil in the turbine bearing box can be ignited, and the safety of the site is critical.

At present, a supercritical carbon dioxide turbine is still in a research and development stage, a turbine shutdown protection facility is not seen when the dry gas seal of the supercritical carbon dioxide turbine fails, and a related protection method is very important for performance test of the supercritical carbon dioxide turbine. In view of the above, the invention provides a dry gas seal failure protection device for a supercritical carbon dioxide turbine, which provides emergency protection for the operation of the supercritical carbon dioxide turbine.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a supercritical carbon dioxide turbine dry gas seal failure protection device and method capable of providing emergency protection for the operation of a supercritical carbon dioxide turbine.

One aspect of the invention provides a supercritical carbon dioxide turbine dry gas seal failure protection device, comprising:

the cylinder cooling structure is used for cooling the cylinder body in the area near the dry gas seal in the turbine cylinder;

and a carbon dioxide protection unit having a cooling branch for supplying carbon dioxide cooling gas to the cylinder cooling structure and a protection branch for supplying carbon dioxide protection gas to the region near the turbine bearing.

According to one embodiment of the dry gas seal failure protection device for the supercritical carbon dioxide turbine, the cooling branch comprises a carbon dioxide storage tank, a carbon dioxide pump, a heater and an electric stop valve which are connected through pipelines, and an outlet of the cooling branch is connected with an air inlet of a cylinder cooling structure.

According to one embodiment of the dry gas seal failure protection device for the supercritical carbon dioxide turbine, the protection branch comprises a carbon dioxide storage tank and a pneumatic stop valve which are connected through a pipeline, and an outlet of the protection branch is arranged in the area near a turbine bearing.

According to one embodiment of the dry gas seal failure protection device for the supercritical carbon dioxide turbine, the cooling branch and the protection branch are arranged in parallel and connected with the same carbon dioxide storage tank.

According to one embodiment of the supercritical carbon dioxide turbine dry gas seal failure protection device, the protection device comprises a pressure transmitter for monitoring the dry gas seal leakage pressure in real time, a temperature transmitter for monitoring the wall temperature of the cylinder cooling structure in real time and a control unit, wherein the pressure transmitter and the temperature transmitter are electrically connected with the control unit.

According to one embodiment of the supercritical carbon dioxide turbine dry gas seal failure protection device, when the detection temperature value of the temperature transmitter exceeds the limit, the control unit controls the turbine to stop and automatically switches on the cooling branch to cool the area near the dry gas seal in the turbine cylinder; and when the detection pressure value of the pressure transmitter exceeds the limit, the control unit controls the turbine to stop and automatically switches on the protection branch to perform air injection protection on the area near the turbine bearing.

According to one embodiment of the dry gas seal failure protection device for the supercritical carbon dioxide turbine, the cylinder cooling structure is arranged in the cylinder body in the area near the dry gas seal in the turbine cylinder and is of a spiral structure, a serpentine structure or an annular structure.

The invention also provides a supercritical carbon dioxide turbine dry gas seal failure protection method, which utilizes the supercritical carbon dioxide turbine dry gas seal failure protection device to carry out failure protection.

The invention also provides a supercritical carbon dioxide turbine dry gas seal failure protection method, which comprises the steps of controlling the wall temperature overrun, turbine shutdown and carbon dioxide cooling gas introduction to start interlocking, and cooling a cylinder body in the vicinity of the dry gas seal in a turbine cylinder through the external carbon dioxide cooling gas; and (3) carrying out interlocking control on the leakage pressure overrun, turbine shutdown and the start of introducing carbon dioxide protective gas, and carrying out air injection protection on the turbine bearing when the failure dry gas seal fails through the external carbon dioxide protective gas.

According to one embodiment of the supercritical carbon dioxide turbine dry gas seal failure protection method, the cylinder body wall temperature of the area near the dry gas seal in the turbine cylinder is monitored in real time, and meanwhile, the dry gas seal leakage pressure is monitored in real time.

Compared with the conventional scheme, the supercritical carbon dioxide turbine dry gas seal failure protection device and method mainly complete turbine dry gas seal protection under the condition of the over-temperature of the cylinder cooling structure and turbine bearing protection when the dry gas seal fails, on one hand, the dry gas seal is ensured not to be damaged by high temperature, on the other hand, the leaked high-temperature gas after the turbine dry gas seal is realized can be prevented from igniting lubricating oil at the bearing, emergency protection is provided for the supercritical carbon dioxide turbine operation, and safe operation is ensured.

Drawings

FIG. 1 illustrates a schematic diagram of a supercritical carbon dioxide turbine dry gas seal failure protection apparatus according to an exemplary embodiment of the present invention.

Description of reference numerals:

the system comprises a turbine 1, a cylinder 2, a bearing 3, a lubricating oil tank 4, a lubricating oil pump 5, a carbon dioxide storage tank 6, a carbon dioxide pump 7, a heater 8, an electric stop valve 9, a pneumatic stop valve 10, a pressure transmitter 11 and a temperature transmitter 12.

Detailed Description

All of the features disclosed in this specification, or all of the steps in any method or process so disclosed, may be combined in any combination, except combinations of features and/or steps that are mutually exclusive.

Any feature disclosed in this specification may be replaced by alternative features serving equivalent or similar purposes, unless expressly stated otherwise. That is, unless expressly stated otherwise, each feature is only an example of a generic series of equivalent or similar features.

FIG. 1 illustrates a schematic diagram of a supercritical carbon dioxide turbine dry gas seal failure protection apparatus according to an exemplary embodiment of the present invention.

As shown in fig. 1, the supercritical carbon dioxide turbine dry gas seal failure protection device includes a cylinder cooling structure 2 and a carbon dioxide protection unit according to an exemplary embodiment of the present invention. The cylinder cooling structure 2 cools the cylinder block in the area near the dry gas seal in the turbine cylinder, and the main function of the cylinder cooling structure is to reduce the temperature of the turbine cylinder near the dry gas seal so as to ensure that the dry gas seal is not damaged by high temperature.

According to the invention, the cylinder cooling structure 2 is arranged in the cylinder block in the area near the dry gas seal in the cylinder of the turbine 1 and may be of a spiral, serpentine or annular configuration.

Because the bearing 3 is connected with the lubricating oil tank 4 through the lubricating oil pump 5, the lubricating oil from the lubricating oil tank 4 is conveyed to the bearing 3 through the lubricating oil pump 5, when the dry gas seal fails, the high-temperature and high-pressure carbon dioxide in the turbine 1 is sprayed to the site, and the lubricating oil in the turbine bearing tank can be ignited, so that the safety of the site is critical. The carbon dioxide protection unit can provide carbon dioxide cooling gas to the cylinder cooling structure 2 for cooling, and can provide carbon dioxide protection gas to the region near the turbine bearing for protection.

Specifically, the carbon dioxide protection unit of the present invention has a cooling branch for supplying carbon dioxide cooling gas to the cylinder cooling structure 2, and has a protection branch for supplying carbon dioxide protection gas to the area near the bearing 2 of the turbine 1. The carbon dioxide cooling gas of the present invention is a carbon dioxide gas obtained by pressurizing and heating a carbon dioxide gas source from a carbon dioxide storage tank or the like, and the carbon dioxide shielding gas of the present invention is a carbon dioxide gas obtained directly from a carbon dioxide gas source from a carbon dioxide storage tank or the like without any other treatment.

Wherein, the cooling branch road includes carbon dioxide storage tank 6, carbon dioxide pump 7, heater 8 and the electronic stop valve 9 that links to each other through the pipeline, and the export of cooling branch road links to each other with the air inlet of cylinder cooling structure 2. When a carbon dioxide cooler is needed to be provided for the cylinder cooling structure 2 to cool the cylinder body, the low-temperature carbon dioxide flowing out of the carbon dioxide storage tank 6 enters the cylinder cooling structure 2 after being pressurized by the carbon dioxide pump 7 and heated by the heater 8, and the cooling of the cylinder body of the turbine cylinder near the dry gas seal is completed.

The protection branch comprises a carbon dioxide storage tank 6 and a pneumatic stop valve 9 which are connected through a pipeline, and an outlet of the protection branch is arranged in the area near the turbine bearing 3. When the bearing 3 needs to be protected, carbon dioxide in the carbon dioxide storage tank 6 is sprayed to the position near the turbine bearing 3 through a pipeline, so that the bearing protection is realized.

Preferably, the cooling branch is arranged in parallel with the protection branch and is connected to the same carbon dioxide storage tank 6, but the present invention is not limited thereto.

According to the invention, the protection device also comprises a pressure transmitter 11 for monitoring the dry gas seal leakage pressure in real time, a temperature transmitter 12 for monitoring the wall temperature of the cylinder cooling structure in real time and a control unit (not shown), wherein the pressure transmitter 11 and the temperature transmitter 12 are electrically connected with the control unit to realize automatic interlocking control in the operation process.

When the detected temperature value of the temperature transmitter 11 exceeds the limit, the control unit controls the turbine 1 to stop and automatically switches on the cooling branch to cool the area near the dry gas seal in the turbine cylinder; when the detection pressure value of the pressure transmitter 12 exceeds the limit, the control unit controls the turbine 1 to stop and automatically switches on the protection branch to perform air injection protection on the area near the turbine bearing. Therefore, dry gas sealing failure protection can be achieved through the device.

The failure protection method of the invention specifically comprises the following steps: the wall temperature is over-limited, the turbine is shut down and carbon dioxide cooling gas is introduced to start interlocking control, and the cylinder body in the area near the dry gas seal in the turbine cylinder is cooled by the external carbon dioxide cooling gas; and simultaneously, the leakage pressure is over-limited, the turbine is shut down and carbon dioxide protective gas is introduced to start interlocking control, and the turbine bearing when the failure dry gas seal fails is subjected to air injection protection through the external carbon dioxide protective gas. The temperature monitoring can be realized by monitoring the wall temperature of the cylinder body in the area near the dry gas seal in the turbine cylinder in real time, and the pressure monitoring can be realized by monitoring the dry gas seal leakage pressure in real time.

That is, through real-time supervision cylinder cooling structure wall temperature, with wall temperature transfinite and turbine shut down and cooling branch start-up interlocking control, the cooling branch is through external carbon dioxide air supply and cool down cylinder cooling structure after rising the temperature to the carbon dioxide pressure boost. The leakage pressure is subjected to real-time monitoring, the leakage pressure is subjected to over-limit and turbine shutdown and the protection branch is started to be interlocked and controlled, and the protection branch is externally connected with a carbon dioxide source and carries out protection on a turbine bearing when the failure dry gas seal fails.

The present invention will be further described with reference to the following specific examples.

The structure of the dry gas seal failure protection device of the supercritical carbon dioxide turbine in the embodiment adopts the structure shown in figure 1.

The working process of the supercritical carbon dioxide turbine dry gas seal failure protection device is as follows:

A. controlling a pressure transmitter and a temperature transmitter to respectively monitor the dry gas seal leakage pressure and the wall temperature of the cylinder cooling structure in real time;

B. and performing logic judgment and control based on the measurement data.

When the wall temperature of the cylinder cooling structure measured by the temperature transmitter exceeds the limit, the turbine is automatically stopped, the electric stop valve is automatically opened, the heater is automatically put in, low-temperature carbon dioxide flowing out of the carbon dioxide storage tank is pressurized by the carbon dioxide pump, and the heated low-temperature carbon dioxide enters the cylinder cooling structure to complete cooling of the cylinder body of the turbine cylinder near the dry gas seal. When the wall temperature of the cylinder cooling structure is lower than the limit value, the electric stop valve is automatically closed, and the heater is automatically cut off;

when the dry gas seal leakage pressure measured by the pressure transmitter exceeds the limit, the turbine is automatically stopped, the pneumatic stop valve is automatically opened, and low-temperature carbon dioxide flowing out of the carbon dioxide storage tank is sprayed to the position near the turbine bearing through a pipeline, so that the high-temperature gas leaked after the dry gas seal of the turbine is realized is prevented from igniting lubricating oil at the bearing.

The invention is not limited to the foregoing embodiments. The invention extends to any novel feature or any novel combination of features disclosed in this specification and any novel method or process steps or any novel combination of features disclosed.