System for recovering residual pressure energy of CO2 generated by low-temperature methanol washing process

Abstract

The utility model discloses a system for recovering residual pressure energy of CO2 generated by utilizing a low-temperature methanol washing process, which comprises a CO2 gas tank, a filter, a gas inlet valve group, a pressure reducing valve, a cantilever turbine, a circulating water pump and a downstream network pipe, the output end of the CO2 gas tank is communicated with the input end of the filter through a shunt pipe, and the CO2 gas generated by the low-temperature methanol washing process is filtered; the output end of the filter is connected with the input end of the air inlet valve set through a CO2 air pipe, the output end of the air inlet valve set is communicated with the input end of the cantilever turbine through a CO2 air pipe, the rotating shaft end of the cantilever turbine is connected with the circulating water pump, and the output end of the cantilever turbine is communicated with the downstream net pipe through an exhaust pipe. CO2 excess pressure energy generated by the low-temperature methanol washing process is fully utilized, energy waste is avoided, the obtained energy can drag the circulating water pump to operate to provide circulating water for other processes, a motor is replaced to drive the circulating water pump, and the electricity utilization cost is saved.

Description

Technical Field

[0001] This utility model relates to the field of residual pressure energy recovery technology, and in particular to a CO2 residual pressure energy recovery system using a low-temperature methanol washing process. Background Technology

[0002] The large amount of CO2 gas generated in the low-temperature methanol washing process is pressurized. This gas needs to be depressurized by a pressure reducing valve before being supplied to downstream processes. Existing pressure reducing systems are specifically as follows: Figure 1 As shown, in this situation, a large amount of residual pressure energy is consumed by the pressure reducing valve, which can easily lead to a huge waste of energy. Utility Model Content

[0003] The purpose of this invention is to provide a CO2 residual pressure energy recovery system that utilizes the low-temperature methanol washing process. This system can fully utilize the CO2 residual pressure energy generated by the low-temperature methanol washing process, avoid energy waste, and the obtained energy can drive the operation of the circulating water pump, replacing the motor-driven circulating water pump and saving electricity costs.

[0004] This invention provides a CO2 residual pressure energy recovery system utilizing a low-temperature methanol washing process, comprising: a CO2 tank, a filter, an inlet valve assembly, a pressure reducing valve, a cantilever turbine, a circulating water pump, and a downstream pipeline.

[0005] The output end of the CO2 gas tank is connected to the input end of the filter through a split pipe to filter the CO2 gas stored in the CO2 gas tank after being produced by the low-temperature methanol washing process. The output end of the filter is connected to the input end of the inlet valve group through a CO2 gas pipe. The output end of the inlet valve group is connected to the input end of the cantilever turbine through a CO2 gas pipe. The rotating shaft end of the cantilever turbine is connected to the circulating water pump. The output end of the cantilever turbine is connected to the downstream network pipe through an exhaust pipe.

[0006] Preferably, the diversion pipeline is equipped with a first manual gate valve.

[0007] Preferably, the diversion pipe is equipped with a first electric switching valve, one end of which is connected to the CO2 gas tank via the diversion pipe and a first manual gate valve, and the other end of which is connected to the filter via a CO2 gas pipe.

[0008] Preferably, a pressure reducing valve is also included, which is connected in parallel with the cantilever turbine via a CO2 gas pipe.

[0009] Preferably, the pressure reducing valve is closed when the cantilever turbine is running, and put into use when the cantilever turbine or the circulating water pump stops.

[0010] Preferably, a diaphragm coupling is provided between the cantilever turbine and the circulating water pump.

[0011] Preferably, the intake valve assembly consists of a quick-closing valve and a regulating valve.

[0012] Preferably, the exhaust pipe connecting the cantilever turbine and the downstream network pipe is equipped with a second electric switch valve and a second manual gate valve.

[0013] Preferably, the cantilever turbine is constructed of precipitation-hardened stainless steel.

[0014] Because of the adoption of the above technical solution, this utility model has the following advantages and positive effects compared with the prior art:

[0015] 1. This utility model utilizes a low-temperature methanol washing process to generate CO2. After passing through a manual gate valve, the CO2 is diverted to an electric switch valve via a branch pipe. This valve is then connected to a filter and an intake valve assembly via a CO2 gas pipe. The CO2 then enters a cantilever turbine, which drives the impeller shaft system to rotate. The turbine is connected to a circulating water pump via a diaphragm coupling. The rotation of the circulating water pump provides circulating water for other processes. The turbine is connected to an exhaust pipe, which is connected to a downstream network pipe. This fully utilizes the residual pressure energy of the CO2 generated by the low-temperature methanol washing process, avoiding energy waste. The obtained energy can drive the circulating water pump to provide circulating water for other processes, replacing the motor-driven circulating water pump and saving electricity costs.

[0016] 2. The CO2 residual pressure energy recovery system provided by this utility model, which utilizes the low-temperature methanol washing process, includes a CO2 tank, a pressure reducing valve, a cantilever turbine, a circulating water pump, and a downstream network pipe. After passing through a manual gate valve, the CO2 is connected to an electric switching valve via a diversion pipe. It is then connected to a filter and an inlet valve group through a CO2 gas pipe, and finally enters the cantilever turbine. The rotating shaft of the cantilever turbine is connected to the circulating water pump, and the turbine is connected to an exhaust pipe. The exhaust pipe is connected to the downstream network pipe. This system can fully utilize the CO2 residual pressure energy generated by the low-temperature methanol washing process, avoiding energy waste. The obtained energy can drive the circulating water pump, replacing the motor-driven circulating water pump and saving electricity costs. Attached Figure Description

[0017] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings, wherein:

[0018] Figure 1 This is a schematic diagram of an existing system in the background art of the present utility model embodiment;

[0019] Figure 2 This is an example diagram of the CO2 residual pressure energy recovery system using the low-temperature methanol washing process described in this embodiment of the invention;

[0020] in,

[0021] 1-CO2 gas tank; 2-First manual gate valve; 3-First electric switch valve; 4-Filter; 5-Inlet valve assembly; 6-Circulating water pump; 7-Cantilever turbine; 8-Second electric switch valve; 9-Pressure reducing valve; 10-Second manual gate valve; 11-Downstream network pipe. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise ratios, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0023] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0024] Example 1

[0025] like Figure 2As shown, this utility model provides a system for driving a circulating water pump 6 using the residual pressure energy of CO2 generated by a low-temperature methanol washing process. The system includes: a CO2 tank 1, a filter 4, an inlet valve assembly 5, a pressure reducing valve 9, a cantilever turbine 7, a circulating water pump 6, and a downstream network pipe 11. The output end of the CO2 tank 1 is connected to the input end of the filter 4 via a diverter pipe, filtering the CO2 gas (i.e., the residual pressure energy of CO2) stored in the CO2 tank 1 after being produced by the low-temperature methanol washing process. The output end of the filter 4 is connected to the input end of the inlet valve assembly 5 via a CO2 pipe. The output end of the inlet valve assembly 5 is connected to the input end of the cantilever turbine 7 via a CO2 pipe. The shaft end of the cantilever turbine 7 is connected to the circulating water pump 6. The output end of the cantilever turbine 7 is connected to the downstream network pipe 11 via an exhaust pipe. This can be understood as follows: CO2 tank 1 stores CO2 gas produced from the low-temperature methanol washing process. This gas carries residual pressure energy, which is the basis for subsequent energy conversion. The input end of filter 4 is connected to the output end of CO2 tank 1 through a split pipe, filtering out large particulate impurities in the CO2 gas. Because the gas coming out of the process may contain impurities, if these impurities are not removed, they may damage subsequent valves, turbines, and other equipment, affecting the normal operation and service life of the equipment. The output end of filter 4 is connected to the input end of inlet valve group 5 through a CO2 gas pipe, which plays a role in regulating gas flow and pressure. It can precisely control the amount of gas entering the cantilever turbine 7 according to the system's operating requirements, ensuring that the turbine can operate stably and efficiently. The output end of inlet valve group 5 is connected to the input end of cantilever turbine 7 through a CO2 gas pipe. Cantilever turbine 7 is the core component of the entire system. It converts the residual pressure energy of CO2 gas into mechanical energy. When CO2 gas enters the turbine, the gas expands and does work, driving the turbine impeller to rotate. The shaft end of the cantilever turbine 7 is connected to the circulating water pump 6, allowing the mechanical energy generated by the turbine impeller rotation to be directly transferred to the circulating water pump 6, enabling it to start operating and providing the necessary circulating water for other processes. The output end of the cantilever turbine 7 is connected to the downstream network pipe 11 via an exhaust pipe. This means that after the CO2 gas completes its work in the turbine, the remaining low-pressure gas enters the downstream network pipe 11 through the exhaust pipe, providing CO2 gas for other processes and achieving comprehensive resource utilization.

[0026] The aforementioned system utilizes the residual pressure energy of CO2 generated by the low-temperature methanol washing process. Through a series of connected and converted devices, the pressure energy of the gas is ultimately converted into the mechanical energy of the rotating circulating water pump 6. Specifically, CO2 gas with a certain pressure exits from the gas tank, passes through filter 4 to remove impurities, and then enters the cantilever turbine 7 after being regulated by the inlet valve group 5. Inside the turbine, the gas expands and does work, driving the impeller to rotate, which in turn drives the circulating water pump 6 at the shaft end to rotate, realizing the transfer and conversion of energy from gas to machinery. The flow of CO2 gas in the entire system is orderly, starting from the gas tank, passing through filter 4, inlet valve group 5, cantilever turbine 7, and finally reaching the downstream network pipe 11. Each component plays a specific role in the gas flow process, and the system design ensures the full utilization of CO2 gas, meeting both the needs of circulating water and the CO2 usage requirements of other processes. The residual pressure energy of CO2 generated in the low-temperature methanol washing process is effectively recovered and converted into useful mechanical energy to drive the circulating water pump 6, reducing resource waste. In chemical production and other processes, the efficient use of energy is of great significance for reducing costs, improving economic benefits and protecting the environment.

[0027] In one embodiment, a first manual gate valve 2 is provided on the diversion pipeline to cut off or open the fluid when needed. For example, when the filter 4 needs to be inspected, maintained, or replaced, the CO2 gas flowing to the filter 4 through the diversion pipeline can be cut off by closing the first manual gate valve 2, thus disconnecting the filter 4 from the fluid connection of the entire system, facilitating operation; it serves the functions of cutting off and opening, but the manual gate valve can also coarsely adjust the fluid flow rate to some extent. By partially opening the gate valve, the flow rate of CO2 gas flowing through the diversion pipeline can be limited, which may be used in certain special cases, such as adjusting the system's operating parameters or adapting to different process requirements. The first manual gate valve 2 is used to close the gas inlet and outlet during the maintenance of the entire system.

[0028] In one embodiment, a first electrically operated switch valve 3 is provided on the diversion pipe. One end of the first electrically operated switch valve 3 is connected to the CO2 gas tank 1 via the diversion pipe and a first manually operated gate valve 2, and the other end of the first electrically operated switch valve 3 is connected to the filter 4 via a CO2 gas pipe. The system incorporates both the first electrically operated switch valve 3 and the first manually operated gate valve 2, achieving a combination of automated and manual control. The manually operated gate valve can be used as a backup or in special circumstances such as emergency maintenance or initial commissioning, while the electrically operated switch valve is used for automatic control during normal system operation, improving the system's flexibility and reliability and enabling it to better adapt to different operational needs. Through the cooperation of the electrically operated switch valve and the manually operated gate valve, the flow rate of CO2 gas to the filter 4 can be more precisely controlled.

[0029] The system utilizes the high-pressure CO2 gas generated by the low-temperature methanol washing process to enter the CO2 tank 1. After passing through the first manual gate valve 2, it enters the filter 4 through the first electric switch valve 3 connected to the diversion pipe to filter large particulate impurities. Then, it enters the cantilever turbine 7 through the inlet valve group 5 composed of a quick-closing valve and a regulating valve. The expansion and work drive the impeller to rotate, the impeller drives the shaft to rotate, the shaft drives the coupling to rotate, and the coupling drives the circulating water pump 6 to rotate to provide circulating water for other processes. The low-pressure CO2 after expansion and work enters the downstream network pipe 11 through the second electric switch valve 8 and the second manual gate valve 10 to provide the required CO2 for other processes.

[0030] In one embodiment, a pressure reducing valve 9 is also included. The pressure reducing valve 9 is connected in parallel with the cantilever turbine 7 via a CO2 gas pipe and is used to regulate the pressure of the CO2 gas. When the CO2 gas pressure in the system is too high, exceeding the pressure that the cantilever turbine 7 can withstand or the pressure required by downstream processes, the pressure reducing valve 9 can automatically reduce the gas pressure. A key purpose of its parallel connection with the cantilever turbine 7 is to provide protection. If the pressure of the CO2 gas entering the cantilever turbine 7 suddenly increases, exceeding the turbine's normal operating range, it may damage the turbine, such as causing impeller deformation or shaft seal damage. The pressure reducing valve 9 can release excess pressure in a timely manner, ensuring that the turbine operates under normal pressure conditions, extending the equipment's service life, and also ensuring the safe and stable operation of the entire system. Simultaneously, the presence of the pressure reducing valve 9 helps optimize the performance of the entire system. In the system, different components may have different pressure requirements. By reasonably setting the pressure parameters of the pressure reducing valve 9, the CO2 gas entering each component can be kept at its optimal pressure, thereby improving the system's operating efficiency. The parallel connection of the pressure reducing valve 9 with the cantilever turbine 7 provides a bypass channel for the CO2 gas. When maintenance or repair of the turbine is required, or when not all gas needs to pass through the turbine to perform work during startup, the state of the pressure reducing valve 9 and related valves can be adjusted to allow some or all of the CO2 gas to bypass the cantilever turbine 7 and flow directly to the downstream pipeline after pressure reduction treatment via the pressure reducing valve 9. This ensures flexible distribution and pressure control of the gas flow without affecting the overall system operation. This parallel setup allows the pressure reducing valve 9 to operate independently of the cantilever turbine 7 to a certain extent.

[0031] In one embodiment, when the cantilever turbine 7 is running, the pressure reducing valve 9 is in the closed state. When the cantilever turbine 7 or the circulating water pump 6 stops, the pressure reducing valve 9 is activated. When the cantilever turbine 7 is running normally, the main purpose of the system is to utilize the residual pressure energy of the CO2 gas to drive the cantilever turbine 7 to rotate, thereby driving the circulating water pump 6. At this time, the pressure reducing valve 9 is in the closed state to ensure that the gas from the CO2 tank 1 can flow preferentially and efficiently to the cantilever turbine 7. Only by allowing sufficient pressure and flow of gas through the turbine can it reach its optimal operating state, achieve effective energy conversion, and provide sufficient power to the circulating water pump 6. When the cantilever turbine 7 stops running, the CO2 gas that was originally flowing to the turbine suddenly has nowhere to go. If not handled in time, the gas will accumulate in the pipeline, causing the system pressure to rise rapidly. Similarly, when the circulating water pump 6 stops working, although it no longer consumes energy converted from the cantilever turbine 7, CO2 gas will still flow out of the gas tank. The pressure reducing valve 9 can promptly reduce the excess gas pressure, releasing the pressure and preventing safety risks such as pipe rupture or equipment damage caused by excessive system pressure. The pressure reducing valve 9 also plays a crucial protective role when the cantilever turbine 7 or the circulating water pump 6 stops. It can prevent uncontrolled gas pressure caused by equipment shutdown, allowing the system to smoothly transition to a new operating state or a safe shutdown state.

[0032] In one embodiment, a diaphragm coupling is provided between the cantilever turbine 7 and the circulating water pump 6, which is easy to install, has a large axial and radial compensation range, and avoids damage to the unit caused by errors during installation or operation.

[0033] In one embodiment, the intake valve group 5 consists of a quick-closing valve and a regulating valve, and adopts a servo pump-controlled electro-hydraulic actuator, which has the characteristics of rapid response, small error and high precision, ensuring smooth adjustment of turbine start-up, operation and shutdown.

[0034] In one embodiment, a second electrically operated switch valve 8 and a second manually operated gate valve 10 are provided on the exhaust pipe connecting the cantilever turbine 7 and the downstream network pipe 11. The second manually operated gate valve 10 is used to shut off the gas inlet and outlet during system maintenance.

[0035] In one embodiment, the cantilever turbine 7 adopts a precipitation-hardened stainless steel structure. The cantilever turbine 7 is an energy-saving and high-efficiency turbine, its material is precipitation-hardened stainless steel, the impeller and blades are integrally forged and milled, and an external protective coating is added. It adopts a high-speed design, which reduces the diameter of the impeller and reduces the overall size and floor space of the unit.

[0036] The working process of this system is as follows: High-pressure CO2 gas generated by the low-temperature methanol washing process enters CO2 tank 1, passes through the first manual gate valve 2, and then through the first electric switch valve 3 connected to the diversion pipe to enter the filter 4 to filter large particulate impurities. The pressure reducing valve 9 is in the closed state, and then passes through the intake valve group 5 composed of a quick-closing valve and a regulating valve to enter the cantilever turbine 7. The expansion and work drive the impeller to rotate, the impeller drives the shaft to rotate, the shaft drives the coupling to rotate, and the coupling drives the circulating water pump 6 to rotate to provide circulating water for other processes. The low-pressure CO2 after expansion and work enters the downstream network pipe 11 through the second electric switch valve 8 and the second manual gate valve 10 to provide the required CO2 for other processes.

[0037] This system can operate stably for a long time under conditions of extreme pressure and flow fluctuations. It is simple to operate and highly automated. It meets the downstream CO2 demand while also meeting the requirements of other process circulating water, forming a perfect match with the overall process.

[0038] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they shall still fall within the protection scope of the present invention.

Claims

1. A CO2 residual pressure energy recovery system utilizing a low-temperature methanol washing process, characterized in that, include: CO2 gas cylinders, filters, inlet valve assemblies, pressure reducing valves, cantilever turbines, circulating water pumps, and downstream piping. The output end of the CO2 gas tank is connected to the input end of the filter through a split pipe to filter the CO2 gas stored in the CO2 gas tank after being produced by the low-temperature methanol washing process. The output end of the filter is connected to the input end of the inlet valve group through a CO2 gas pipe. The output end of the inlet valve group is connected to the input end of the cantilever turbine through a CO2 gas pipe. The rotating shaft end of the cantilever turbine is connected to the circulating water pump. The output end of the cantilever turbine is connected to the downstream network pipe through an exhaust pipe.

2. The CO2 residual pressure energy recovery system utilizing the low-temperature methanol washing process according to claim 1, characterized in that, The diversion pipeline is equipped with a first manual gate valve.

3. The CO2 residual pressure energy recovery system utilizing the low-temperature methanol washing process according to claim 2, characterized in that, The diversion pipe is equipped with a first electric switch valve. One end of the first electric switch valve is connected to the CO2 gas tank through the diversion pipe and a first manual gate valve. The other end of the first electric switch valve is connected to the filter through the CO2 gas pipe.

4. The CO2 residual pressure energy recovery system utilizing the low-temperature methanol washing process according to claim 2, characterized in that, It also includes a pressure reducing valve, which is connected in parallel with the cantilever turbine via a CO2 gas pipe.

5. The CO2 residual pressure energy recovery system utilizing the low-temperature methanol washing process according to claim 1, characterized in that, When the cantilever turbine is running, the pressure reducing valve is in the closed state. When the cantilever turbine or the circulating water pump stops, the pressure reducing valve is put into use.

6. The CO2 residual pressure energy recovery system using the low-temperature methanol washing process according to claim 1, characterized in that, A diaphragm coupling is provided between the cantilever turbine and the circulating water pump.

7. The CO2 residual pressure energy recovery system using the low-temperature methanol washing process according to claim 1, characterized in that, The intake valve assembly consists of a quick-closing valve and a regulating valve.

8. The CO2 residual pressure energy recovery system utilizing the low-temperature methanol washing process according to claim 1, characterized in that, The exhaust pipe connecting the cantilever turbine and the downstream network is equipped with a second electric switch valve and a second manual gate valve.

9. The CO2 residual pressure energy recovery system using the low-temperature methanol washing process according to claim 1, characterized in that, The cantilever turbine is constructed of precipitation-hardened stainless steel.

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