Feed gas pressurization system and control method therefor

Abstract

The present invention provides a feed gas pressurization system and a control method therefor, belonging to the technical field of low-carbon blast furnace feed gas processing equipment. The system comprises a gas supply pipeline and a liquid supplementation pipeline; a pressurizer has an inlet and an outlet, the gas supply pipeline and the liquid replenishing pipeline each being in communication with the inlet of the pressurizer; a heat recovery device has a first heat exchange channel and a second heat exchange channel for mutual heat exchange; a gas-liquid separator has a mixture inlet and a gas outlet, the outlet of the pressurizer is communicated with an inlet of the first heat exchange channel, an outlet of the first heat exchange channel being in communication with the mixture inlet of the gas-liquid separator, and the gas outlet of the gas-liquid separator being in communication with an inlet of the second heat exchange channel. The present invention purifies feed gas, and reduces the probability of subsequent equipment being blocked or failing due to impurities in the feed gas. At the same time, the purified feed gas is used to cool a gas-liquid mixture, which is beneficial for gas-liquid separation of the gas-liquid mixture, and fully utilizes heat absorbed by the gas-liquid mixture, to improve energy utilization efficiency.

Description

A raw gas pressurization system and control method thereof Technical Field

[0001] The present invention relates to the technical field of low-carbon blast furnace raw gas processing equipment, and in particular to a raw gas pressurizing system and a control method thereof. Background Art

[0002] Currently, the steel industry largely utilizes the long blast furnace-converter process, with the shorter shaft furnace plus electric furnace process being used to a lesser extent. Furthermore, coal is one of the primary fossil fuels in the steel industry. In this context, converting carbon to hydrogen or other energy sources is technically challenging and costly. Therefore, the steel industry's primary technical focus for low-carbon transformation lies in improving the utilization efficiency of existing coal gas resources and gradually optimizing its energy mix. Among comprehensive coal gas utilization methods, while specialized processes such as coke oven gas hydrogen production and liquefied natural gas (LNG) offer high added value, other methods utilizing coal gas thermal energy, such as blast furnace gas, converter gas, blast furnace gas mixed with coke oven gas as fuel, and combined gas steam cycle (CCPP) power generation, offer lower added value. However, utilizing the chemical energy of coal gas and injecting it as a reducing gas into blast furnaces can reduce the blast furnace's solid fossil energy consumption, increase the comprehensive utilization value of coal gas in the steel industry, and reduce carbon emissions. The gas resources produced by the steel industry usually contain a large amount of impurities, especially coke oven gas, which contains impurities such as tar and naphthalene. If used directly, it is easy to clog equipment, cause equipment failure, and affect the normal production.

[0003] Summary of the Invention

[0004] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a raw gas pressurization system and a control method thereof, which are used to solve the problems in the prior art that the coal gas resources generated by the steel industry usually contain a large amount of impurities, which easily clog equipment and cause equipment failure.

[0005] To achieve the above and other related objectives, the present invention provides a feed gas pressurization system, comprising:

[0006] A gas supply pipeline, used to supply raw gas to the pressurizer,

[0007] a fluid supply pipe, used for supplying coolant to the pressurizer,

[0008] The pressurizer has an inlet and an outlet, and the air supply pipe and the liquid infusion pipe are respectively connected to the inlet of the pressurizer.

[0009] The heat recovery device has a first heat exchange channel and a second heat exchange channel for exchanging heat with each other.

[0010] Gas-liquid separator, with mixture inlet and gas outlet,

[0011] The outlet of the pressurizer is connected to the inlet of the first heat exchange channel, the outlet of the first heat exchange channel is connected to the mixture inlet of the gas-liquid separator, the gas outlet of the gas-liquid separator is connected to the inlet of the second heat exchange channel, and the outlet of the second heat exchange channel is used to transport the pressurized raw gas to the outside. The gas-liquid mixture discharged from the pressurizer and the raw gas separated by the gas-liquid separator exchange heat in the heat recovery device.

[0012] Optionally, a raw gas reflux pipeline is connected between the gas outlet of the gas-liquid separator and the air inlet pipeline, and a raw gas reflux regulating valve for regulating the flow rate of the raw gas reflux pipeline is provided on the raw gas reflux pipeline.

[0013] Optionally, the gas outlet of the raw gas return pipe extends into the gas inlet pipe, and the angle between the gas outlet direction of the gas outlet and the flow direction of the raw gas in the gas inlet pipe is an acute angle.

[0014] Optionally, the length of the gas outlet extending into the gas inlet pipe is ≥500 mm, and the angle between the gas outlet direction of the gas outlet and the flow direction of the raw gas in the gas inlet pipe is 45°.

[0015] Optionally, the inlet of the pressurizer and the liquid outlet of the gas-liquid separator are connected through a return water pipe.

[0016] Optionally, the return water pipe is provided with a return water filter and a return water regulating valve for regulating the flow of the return water pipe.

[0017] Optionally, a cooler is provided between the heat recovery device and the gas-liquid separator, and the outlet of the first heat exchange channel is connected to the inlet of the gas-liquid separator through the cooler.

[0018] Optionally, a filter is provided on the air intake pipe.

[0019] Optionally, a fluid infusion regulating valve is provided on the fluid infusion pipeline.

[0020] Optionally, the gas-liquid separator is connected to a sewage pipe and a liquid level regulating pipe, and both the sewage pipe and the liquid level regulating pipe are connected to the drainage main pipe.

[0021] The gas-liquid separator is provided with a liquid level sensor, the sewage pipe is provided with a sewage on-off valve, the liquid level regulating pipe is provided with a liquid level regulating valve, and the drainage main pipe is provided with an emergency shut-off valve. The liquid level regulating valve, the sewage on-off valve and the emergency shut-off valve are respectively connected to the liquid level sensor signal and connected to the liquid level sensor signal.

[0022] Optionally, there are multiple liquid level sensors, and the liquid level regulating valve, the sewage discharge on-off valve and the emergency shut-off valve are respectively connected to different liquid level sensors.

[0023] Optionally, a flow limiting orifice plate is provided on the drainage main pipe.

[0024] Optionally, the gas outlet of the gas-liquid separator is connected to the gas supply pipe, and a first flow meter and a second flow meter are respectively provided on the gas outlet pipe. The first flow meter is used to monitor the low flow range of the gas supply pipe, and the second flow meter is used to monitor the high flow range of the gas supply pipe. The sum of the detection ranges of the first flow meter and the second flow meter covers the total flow range of the gas supply pipe.

[0025] Optionally, silencers are respectively provided on the inlet and outlet of the pressurizer.

[0026] Optionally, the inner cavity of the gas-liquid separator is cylindrical, and the gas-liquid mixture pressurized by the pressurizer enters the inner cavity along the tangential direction of the inner cavity.

[0027] The present invention also provides a control method for a raw gas pressurizing system, and provides a raw gas pressurizing system as described above, wherein the raw gas and coolant are pressurized and mixed in the pressurizer to form a gas-liquid mixture, and the gas-liquid mixture enters the gas-liquid separator through the first heat exchange channel for gas-liquid separation. The raw gas after gas-liquid separation is transported outward through the second heat exchange channel, and the gas-liquid mixture in the first heat exchange channel exchanges heat with the raw gas in the second heat exchange channel.

[0028] Optionally, the coolant portion after gas-liquid separation is returned to the inlet of the pressurizer.

[0029] Optionally, part of the raw gas transported outward is returned to the inlet of the pressurizer.

[0030] Optionally, countercurrent heat exchange is performed between the first heat exchange channel and the second heat exchange channel of the heat recovery device.

[0031] As described above, the raw gas pressurization system and control method thereof of the present invention have the following beneficial effects:

[0032] The raw gas and coolant are mixed and pressurized in the pressurizer to form a gas-liquid mixture. The coolant cools the pressurizer to prevent damage while also scrubbing impurities from the raw gas. After the gas-liquid mixture is separated in the gas-liquid separator, impurities in the raw gas remain in the coolant, purifying the raw gas and reducing the chance of subsequent equipment clogging or malfunctioning due to impurities in the raw gas. Simultaneously, after absorbing heat in the pressurizer, the coolant exchanges heat with the purified raw gas in the heat recovery unit. The gas-liquid mixture heats the purified raw gas, raising its temperature for subsequent use and fully utilizing the heat absorbed by the gas-liquid mixture. Furthermore, the purified raw gas cools the gas-liquid mixture, facilitating its separation in the gas-liquid separator and preventing the high temperature of the gas-liquid mixture from carrying excessive moisture, which could affect the operation of the blast furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] FIG1 is a schematic diagram showing the layout of a raw gas pressurization system according to an embodiment of the present invention.

[0034] FIG. 2 is a partial enlarged schematic diagram of FIG. 1 .

[0035] FIG3 is a second partial enlarged schematic diagram of FIG1 .

[0036] FIG4 is a schematic structural diagram of a gas-liquid separator according to an embodiment of the present invention.

[0037] FIG5 is a schematic structural diagram showing the connection between the gas outlet of the raw gas return pipe and the gas inlet pipe in an embodiment of the present invention.

[0038] Explanation of the accompanying symbols: air intake pipe 1, pressurizer 2, heat recovery device 3, cooler 4, gas-liquid separator 5, raw gas reflux pipe 6, raw gas reflux regulating valve 7, liquid level regulating outlet 8, air intake regulating valve 9, return water pipe 10, return water filter 11, return water regulating valve 12, sewage pipe 13, sewage on-off valve 14, liquid level regulating valve 15, liquid level regulating pipe 16, emergency shut-off valve 17, drainage main pipe 18, liquid replenishment pipe 20, liquid replenishment regulating valve 21, muffler 22, mixture inlet 23, gas outlet 24, safety valve port 25, liquid outlet 26, sewage outlet 27. DETAILED DESCRIPTION

[0039] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention.

[0040] It should be noted that the diagrams provided in the present embodiment are only schematic illustrations of the basic concept of the present invention. The diagrams only show the components related to the present invention and are not drawn according to the number, shape and size of the components during actual implementation. The type, quantity and ratio of each component during actual implementation can be changed at will, and the component layout type may also be more complex. The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read. They are not used to limit the limiting conditions for the implementation of the present invention. Therefore, they have no technical significance. Any modification of the structure, change of the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the efficacy and purpose of the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be considered as the scope of the implementation of the present invention without substantially changing the technical content.

[0041] Referring to Figures 1 to 5, this embodiment provides a raw gas pressurization system, including a pressurizer 2, a heat recovery device 3, and a gas-liquid separator 5. The inlet of the pressurizer 2 is connected to an air inlet pipe 1 and a liquid replenishing pipe 20, respectively. The air inlet pipe 1 is used to supply raw gas to the pressurizer 2, and the liquid replenishing pipe 20 is used to supply coolant to the pressurizer 2. The heat recovery device 3 has a first heat exchange channel and a second heat exchange channel for exchanging heat with each other. The outlet of the pressurizer 2 is connected to the inlet of the first heat exchange channel, and the outlet of the first heat exchange channel is connected to the mixture inlet 23 of the gas-liquid separator 5. The gas outlet 24 of the gas-liquid separator 5 is connected to the inlet of the second heat exchange channel. The outlet of the second heat exchange channel is used to supply pressurized raw gas to the outside. In this embodiment, the raw gas pressurization system is used to supply raw gas to a low-carbon blast furnace.

[0042] A raw gas reflux pipeline 6 is connected between the gas outlet 24 of the gas-liquid separator 5 and the gas inlet pipeline 1 . A raw gas reflux regulating valve 7 for regulating the flow rate of the raw gas reflux pipeline 6 is provided on the raw gas reflux pipeline 6 .

[0043] In this embodiment, the feed gas is coal gas, and the coolant is softened water. Softened water has a low hardness, which reduces scale buildup in the system's pipes, prevents clogging, and ensures heat exchange efficiency. Pressurizer 2 utilizes a screw compressor, which has the advantages of fewer parts, high reliability, and a long service life.

[0044] Specifically, in this embodiment, countercurrent heat exchange is performed between the first heat exchange channel and the second heat exchange channel of the heat recovery device 3, that is, the medium flow directions in the first heat exchange channel and the second heat exchange channel are opposite. Countercurrent heat exchange helps to increase the heat exchange efficiency between the gas-liquid mixture and the separated raw gas, thereby ensuring the heat exchange effect.

[0045] Please refer to FIG5 . In this embodiment, the outlet of the raw gas return pipe 6 extends into the air inlet pipe 1 , and the angle between the outlet direction and the flow direction of the raw gas in the air inlet pipe 1 is an acute angle.

[0046] Specifically, in this embodiment, the length of the outlet of the raw gas return pipe 6 extending into the air inlet pipe 1 is ≥500 mm, and the angle between the outlet direction and the flow direction of the raw gas in the air inlet pipe 1 is 45°.

[0047] The raw gas return pipe 6 and the raw gas intake pipe 1 are connected at 45 degrees, and the raw gas return pipe 6 is extended 500mm into the intake pipe 1 to prevent the high-pressure return gas in the raw gas return pipe 6 from directly flushing the raw gas intake pipe 1, which can reduce the noise generated by the raw gas return pipe 6.

[0048] As shown in Figure 1, in this embodiment, the gas-liquid separator 5 has a liquid outlet 26. A return pipe 10 is provided between the liquid outlet 26 and the inlet of the pressurizer 2. The inlet of the pressurizer 2 communicates with the liquid outlet 26 of the gas-liquid separator 5 via the return pipe 10. Therefore, coolant at the bottom of the gas-liquid separator 5 can be returned to the inlet of the pressurizer 2 via the return pipe 10, where it is used to cool the pressurizer 2. This allows for recycling of the coolant, reducing production costs.

[0049] At the same time, in this embodiment, a return water filter 11 and a return water regulating valve 12 for regulating the flow of the return water pipe 10 are provided on the return water pipe 10. The return water filter 11 can filter and process the coolant flowing back through the return water pipe 10.

[0050] In this embodiment, a cooler 4 is further provided between the heat recovery unit 3 and the gas-liquid separator 5. The outlet of the first heat exchange channel is connected to the mixture inlet 23 of the gas-liquid separator 5 via the cooler 4. The cooler 4 can further cool the gas-liquid mixture discharged from the heat recovery unit 3, further reducing the temperature of the gas-liquid mixture and facilitating gas-liquid separation of the gas-liquid mixture in the gas-liquid separator 5.

[0051] In this embodiment, a filter is installed on the air inlet pipe 1. The raw gas is first processed by the filter before being sent to the screw compressor for pressurization. The filter has a filtration accuracy of 10-100 mesh and can be switched or replaced online. The filter can filter some impurities in the raw gas, reducing the workload of the pressurizer 2 and the gas-liquid separator 5.

[0052] In this embodiment, an air intake regulating valve 9 is also provided on the air intake pipe 1. The air intake regulating valve 9 is located after the connection between the raw gas return pipe 6 and the air intake pipe 1, and is used to adjust the total amount of raw gas provided by the air intake pipe 1 to the pressurizer 2.

[0053] As shown in Figure 3, in this embodiment, the gas-liquid separator 5 is connected to a sewage pipe 13 and a liquid level regulating pipe 16. The sewage pipe 13 and the liquid level regulating pipe 16 are both connected to a drainage main 18. The gas-liquid separator 5 is provided with a liquid level sensor, the sewage pipe 13 is provided with a sewage on-off valve 14, the liquid level regulating pipe 16 is provided with a liquid level regulating valve 15, and the drainage main 18 is provided with an emergency shut-off valve 17. The liquid level regulating valve 15, the sewage on-off valve 14, and the emergency shut-off valve 17 are respectively connected to the liquid level sensor signal. Because the raw gas contains a certain amount of humidity, gaseous water will liquefy and precipitate during the pressurization and cooling process of the raw gas and need to be continuously discharged. In addition, because the raw gas is relatively dirty, the softened water needs to be replaced from time to time after being circulated for a period of time. Therefore, it is necessary to discharge the liquefied water in the system and replenish the softened water from time to time.

[0054] Excessive coolant in the gas-liquid separator 5 is discharged through the liquid level regulating pipe 16, and the sewage at the bottom of the gas-liquid separator 5 is discharged through the sewage pipe 13. The liquid level regulating pipe 16 and the sewage pipe 13 converge into the drainage main pipe 18. The drainage main pipe 18 is provided with an emergency shut-off valve 17 to prevent the raw gas in the gas-liquid separator 5 from leaking due to the low liquid level at the bottom of the gas-liquid separator 5.

[0055] In this embodiment, the inner cavity of the gas-liquid separator 5 is cylindrical, and the gas-liquid mixture pressurized by the pressurizer 2 enters the inner cavity along a tangential direction of the inner cavity. After being discharged from the outlet of the screw compressor, the mixture of raw gas and softened water is recovered by the heat recovery device, then cooled by the cooler 4, and finally enters the gas-liquid separator 5 for separation. The drain port 27 at the bottom of the gas-liquid separator 5 has a diameter ≥ DN80. The mixture of raw gas and softened water enters the gas-liquid separator 5 along a tangential direction of the inner cavity of the gas-liquid separator 5, allowing the mixture of raw gas and softened water to rotate along the inner wall of the gas-liquid separator 5, thereby effectively separating the raw gas and softened water.

[0056] As shown in Figure 4, in this embodiment, the gas-liquid separator 5 has a high liquid level, a low liquid level, and an excessively low liquid level from top to bottom. The distance between the low liquid level and the high liquid level is ≥500mm, and the distance between the excessively low liquid level and the low liquid level is ≥200mm. Furthermore, the total height of the liquid level in the gas-liquid separator 5 must be ≥1700mm, and the distance between the point where the liquid level regulating pipe 16, where the liquid level regulating valve 15 is located, connects to the gas-liquid separator 5 and the low liquid level must be ≥800mm.

[0057] As shown in Figure 4, the gas-liquid separator 5 is equipped with a mixture inlet 23, a gas outlet 24, a safety valve port 25, a sewage outlet 27, a liquid outlet 26, a liquid level control outlet 8, a connection port for a liquid level gauge, and a connection port for a liquid level transmitter. The mixture inlet 23 is used to receive the adsorbed gas-liquid mixture mixed in the pressurizer 2, the gas outlet 24 is used to discharge the raw gas after separation and purification by the coolant, the safety valve port 25 is used to connect to the safety valve, the sewage outlet 27 is used to communicate with the sewage pipe 13, the liquid outlet 26 is used to communicate with the return pipe 10, and the liquid level control outlet 8 is used to communicate with the liquid level control pipe 16.

[0058] In this embodiment, the sewage outlet 27 is located at the bottom of the gas-liquid separator 5, the liquid outlet 26 and the liquid level regulating outlet 8 are lower than the low liquid level of the gas-liquid separator 5, and the distance between the liquid level regulating outlet 8 and the low liquid level of the gas-liquid separator 5 is ≥800 mm.

[0059] In this embodiment, multiple liquid level sensors are used. The liquid level regulating valve 15, the sewage on-off valve 14, and the emergency shut-off valve 17 are each connected to a different liquid level sensor. Each liquid level sensor is independently configured to prevent interference with each other, thereby increasing the reliability of liquid level detection and preventing overall equipment failure due to damage to a single liquid level sensor. In this embodiment, the liquid level sensors are configured as three independent remote level gauges, and the liquid level regulating valve 15, the sewage on-off valve 14, and the emergency shut-off valve 17 are each connected to a different liquid level sensor signal.

[0060] During normal operation of the gas-liquid separator 5 , the sewage on-off valve 14 and the liquid level regulating valve 15 are both in the closed state, and the liquid level of the softened water in the gas-liquid separator 5 usually maintains a normal liquid level in dynamic balance. At this time, the liquid level regulating valve 15 does not operate.

[0061] When the liquid level in the gas-liquid separator 5 reaches or exceeds the high liquid level, triggering the high liquid level alarm, the liquid level regulating valve 15 on the liquid level regulating pipe 16 opens, discharges the softened water in the gas-liquid separator 5, and lowers the liquid level in the gas-liquid separator 5. When the liquid level in the gas-liquid separator 5 drops to the low liquid level, triggering the low liquid level alarm, the liquid level regulating valve 15 on the liquid level regulating pipe 16 closes.

[0062] In order to discharge impurities such as dust deposited at the bottom of the gas-liquid separator 5, the opening frequency of the sewage discharge on-off valve 14 on the sewage discharge pipe 13 connected to the bottom of the gas-liquid separator 5 can be pre-set according to the impurity content in the raw gas. If the impurity content in the raw gas is high, the opening frequency of the sewage discharge on-off valve 14 is increased; if the impurity content in the raw gas is low, the opening frequency of the sewage discharge on-off valve 14 is reduced. At the same time, when the liquid level is lower than the low liquid level, the emergency shut-off valve 17 on the drainage main pipe 18 is closed to prevent the raw gas in the gas-liquid separator 5 from leaking due to the low liquid level in the gas-liquid separator 5.

[0063] As shown in Figure 2, in this embodiment, a liquid replenishment regulating valve 21 is provided on the liquid replenishment pipeline 20. When the liquid level in the gas-liquid separator 5 drops to a too low level and triggers the low liquid level alarm, the liquid replenishment regulating valve 21 on the liquid replenishment pipeline 20 opens and liquid replenishment begins. When the liquid level in the gas-liquid separator 5 is replenished to a preset height, liquid replenishment is stopped.

[0064] In this embodiment, a flow-restricting orifice is installed on the main drainage pipe 18. To prevent clogging, the drainage pipe 13 at the bottom of the gas-liquid separator 5 and the liquid level control pipe 16 of the gas-liquid separator 5 are typically larger in diameter. To achieve stable and safe sewage discharge, it is necessary to control the discharge rate. Therefore, in this embodiment, a flow-restricting orifice is installed on the main drainage pipe 18. The flow-restricting orifice can reduce liquid level fluctuations caused by automatic drainage and bottom drainage of the gas-liquid separator 5, ensuring smooth discharge of sewage from the gas-liquid separator 5.

[0065] In this embodiment, the gas outlet 24 of the gas-liquid separator 5 is connected to the gas supply pipeline, and a first flow meter and a second flow meter are respectively provided on the gas outlet pipeline. The first flow meter is used to monitor the low flow range of the gas supply pipeline, and the second flow meter is used to monitor the high flow range of the gas supply pipeline. The sum of the detection ranges of the first flow meter and the second flow meter covers the total flow range of the gas supply pipeline.

[0066] In this embodiment, the pressurized raw gas is measured using a dual flow meter, which can accurately measure the flow rate according to the different flow requirements of the injection system.

[0067] In this embodiment, silencers are respectively provided on the inlet and outlet of the pressurizer 2 to reduce the noise of the pressurization system.

[0068] This embodiment also provides a control method for a raw gas pressurization system, and provides a raw gas pressurization system as described above, wherein the raw gas and coolant are pressurized and mixed in a pressurizer to form a gas-liquid mixture, and the gas-liquid mixture enters a gas-liquid separator through a first heat exchange channel for gas-liquid separation, and the raw gas after gas-liquid separation is transported outward through a second heat exchange channel, and the gas-liquid mixture in the first heat exchange channel exchanges heat with the raw gas in the second heat exchange channel.

[0069] In practice, when the raw gas pressurization system is operating, the raw gas first passes through a filter on the intake pipe 1 to remove some solid particulate impurities. After being treated by the filter, the raw gas passes through the muffler at the inlet of the pressurizer 2 and, along with the coolant, enters the screw compressor for pressurization. The coolant entering the screw compressor for pressurization can be returned via the return pipe 10 or replenished via the refill pipe 20. The amount of circulating softened water sprayed can be controlled based on the exhaust temperature at the screw compressor main unit outlet by controlling the return water regulating valve 12 on the circulating return pipe and the refill regulating valve 21 on the refill pipe 20.

[0070] In this embodiment, the mixture of raw gas and coolant is discharged after being pressurized by the screw compressor, and its temperature during discharge needs to be controlled between 80 and 85°C. After being pressurized by the screw compressor, the mixture of raw gas and coolant passes through the muffler and check valve provided at the outlet of the screw compressor, enters the heat recovery unit 3, where the heat is recovered, and then enters the cooler 4 for cooling. The mixture of raw gas and coolant enters the gas-liquid separator 5 for separation. The separated raw gas is discharged from the top of the gas-liquid separator 5 and then enters the heat recovery unit for heating. After being processed by the heat recovery unit, the temperature of the raw gas can be raised to 75°C or above.

[0071] The heated raw gas passes through the outlet check valve and is metered before exiting the system. The raw gas return pipe 6 between the inlet and outlet of the screw compressor can adjust the outlet pressure of the raw gas by adjusting the opening of the raw gas return regulating valve 7 installed thereon according to the outlet pressure setting value.

[0072] Specifically, in this embodiment, during the operation of the screw compressor main unit, it is necessary to control the outlet pressure and adjust the operating flow rate. The opening degree of the raw gas return regulating valve 7 on the raw gas return pipe 6 is often between 10% and 50%. Therefore, the diameter of the raw gas return pipe 6 before the raw gas return regulating valve 7 is usually larger than the diameter after the raw gas return regulating valve 7. In this embodiment, the pipe diameter of the raw gas return pipe 6 before the raw gas return regulating valve 7 is designed according to 100% load, and the pipe diameter after the raw gas return regulating valve 7 is designed according to 50% load, that is, the pipe diameter of the raw gas return pipe 6 before the raw gas return regulating valve 7 is twice the diameter of the pipe after the raw gas return regulating valve 7.

[0073] In this embodiment, the pressure and flow rate of the injection system are adjusted based on the low-carbon blast furnace's demand for raw gas injection by adjusting the opening of the raw gas reflux regulating valve 7 on the raw gas reflux pipe 6 to adjust the injection system's supply pressure. The raw gas supply flow rate is then jointly regulated by the variable frequency motor of the pressurizer 2 and the raw gas reflux regulating valve 7, ensuring stable operation of both the pressurization system and the low-carbon blast furnace raw gas injection system.

[0074] In this embodiment, the heat recovery unit utilizes a shell-and-tube structure, with the first heat exchange channel forming the tube side and the second heat exchange channel forming the shell side. The mixture of raw gas and softened water discharged from the screw compressor main unit flows through the tube side, while the purified raw gas for injection, discharged from the top of the gas-liquid separator 5, flows through the shell side. The heat recovery unit can recover heat exceeding 12% of the screw compressor's shaft power and reduce cooling water usage in the chiller by over 412%.

[0075] Specifically, in this embodiment, in the heat recovery device, the high-temperature raw gas and softened water mixture enters from the top and exits from the bottom, and the low-temperature raw gas separated by the gas-liquid separator 5 enters from the bottom and exits from the top to achieve countercurrent heat exchange between the two.

[0076] In this embodiment, in the cooler 4, the mixture of high-temperature raw gas and softened water discharged from the heat recovery device enters from the top and exits from the bottom, and the low-temperature cooling water enters from the bottom and exits from the top, and countercurrent heat exchange is performed between the two. The countercurrent heat exchange helps to increase the heat exchange efficiency between the gas-liquid mixture and the cooling water in the cooler 4, thereby ensuring the heat exchange effect.

[0077] In this embodiment, the 3 Based on the raw gas injection rate of / h, the specific parameters of the raw gas are as follows:

[0078] Processing result: flow rate 23456Nm 3 / h, pressure of 0.60-0.80 MPa, temperature of 75-80°C, and water content of 0.82%-1.0%.

[0079] With 40000Nm 3 Based on the raw gas injection rate of / h, the specific parameters of the raw gas are as follows:

[0080] Processing result: flow rate 37700Nm 3 / h, pressure of 0.60-0.80 MPa, temperature of 75-80°C, and water content of 0.82%-1.0%.

[0081] In summary, the present embodiment provides a raw gas pressurization system and a control method thereof, wherein the raw gas and the coolant are mixed and pressurized in the pressurizer 2 to form a gas-liquid mixture. The coolant cools the pressurizer 2 to prevent damage to the pressurizer 2 while adsorbing impurities in the raw gas. After the gas-liquid mixture is separated by the gas-liquid separator 5, the impurities in the raw gas remain in the coolant, so that the raw gas can be purified, reducing the probability of subsequent equipment being blocked or malfunctioning due to impurities in the raw gas. At the same time, after the coolant absorbs heat at the pressurizer 2, it exchanges heat with the purified raw gas in the heat recovery device 3, and the gas-liquid mixture heats the purified raw gas, increasing the temperature of the purified raw gas to facilitate subsequent use and fully utilizing the heat absorbed by the gas-liquid mixture. At the same time, the purified raw gas cools the gas-liquid mixture, which is beneficial for the gas-liquid separation of the gas-liquid mixture in the gas-liquid separator 5, and also prevents the gas-liquid mixture from carrying too much water due to the high temperature, which affects the operation of the blast furnace.

[0082] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A pressurization system for a raw material gas, characterized in that, Comprising: A gas supply pipeline for supplying raw gas to the pressurizer; A liquid supply pipeline for supplying coolant to the pressurizer; A pressurizer having an inlet and an outlet, wherein the gas supply pipeline and the liquid supply pipeline are respectively communicated with the inlet of the pressurizer; A heat recovery device having a first heat exchange channel and a second heat exchange channel for heat exchange with each other; A gas-liquid separator having a mixture inlet and a gas outlet; The outlet of the pressurizer is communicated with the inlet of the first heat exchange channel, the outlet of the first heat exchange channel is communicated with the mixture inlet of the gas-liquid separator, the gas outlet of the gas-liquid separator is communicated with the inlet of the second heat exchange channel, the outlet of the second heat exchange channel is used for delivering the pressurized raw gas outwards, and the gas-liquid mixture discharged from the pressurizer exchanges heat with the raw gas separated by the gas-liquid separator in the heat recovery device.

2. The pressurization system for the raw material gas according to claim 1, wherein: A raw gas return pipeline is communicated between the gas outlet of the gas-liquid separator and the intake pipeline, and a raw gas return regulating valve for regulating the flow rate of the raw gas return pipeline is arranged on the raw gas return pipeline.

3. The pressurization system for the raw material gas according to claim 2, characterized in that: The gas outlet of the raw gas return pipeline extends into the intake pipeline, and the angle between the gas outlet direction and the flow direction of the raw gas in the intake pipeline is an acute angle.

4. The pressurization system for the feed gas according to claim 2, wherein: The length of the gas outlet extending into the intake pipeline is ≥500 mm, and the angle between the gas outlet direction and the flow direction of the raw gas in the intake pipeline is 45°.

5. The pressurization system for the raw material gas according to claim 1, characterized in that: The gas-liquid separator has a liquid outlet, and the inlet of the pressurizer is communicated with the liquid outlet of the gas-liquid separator through a return water pipeline.

6. The pressurization system for the raw material gas according to claim 5, characterized in that: A return water filter and a return water regulating valve for regulating the flow rate of the return water pipeline are arranged on the return water pipeline.

7. The pressurization system for the raw material gas according to claim 1, wherein: A cooler is arranged between the heat recovery device and the gas-liquid separator, and the outlet of the first heat exchange channel is communicated with the inlet of the gas-liquid separator through the cooler.

8. The pressurization system for the raw material gas according to claim 1, wherein: A filter is arranged on the intake pipeline.

9. The pressurization system for the raw material gas according to claim 1, characterized in that: A liquid supply regulating valve is arranged on the liquid supply pipeline.

10. The pressurization system for the raw material gas according to claim 1, characterized in that: A sewage discharge pipeline and a liquid level regulating pipeline are communicated with the gas-liquid separator, and both the sewage discharge pipeline and the liquid level regulating pipeline are communicated with a liquid discharge main pipe; A liquid level sensor is arranged on the gas-liquid separator, a sewage discharge on-off valve is arranged on the sewage discharge pipeline, a liquid level regulating valve is arranged on the liquid level regulating pipeline, an emergency shut-off valve is arranged on the liquid discharge main pipe, and the liquid level regulating valve, the sewage discharge on-off valve and the emergency shut-off valve are respectively in signal connection with the liquid level sensor.

11. The pressurization system for the raw material gas according to claim 10, characterized in that: There are multiple liquid level sensors, and the liquid level regulating valve, the sewage discharge on-off valve and the emergency shut-off valve are respectively connected to different liquid level sensors.

12. The pressurization system for the raw material gas according to claim 10, characterized in that: A choke orifice is arranged on the liquid discharge main pipe.

13. The pressurization system for the raw material gas according to claim 1, characterized in that: The gas outlet of the gas-liquid separator is communicated with the gas supply pipeline, and a first flowmeter and a second flowmeter are respectively arranged on the gas outlet pipeline. The first flowmeter is used for monitoring the low flow range of the gas supply pipeline, the second flowmeter is used for monitoring the high flow range of the gas supply pipeline, and the sum of the detection ranges of the first flowmeter and the second flowmeter covers the total flow range of the gas supply pipeline.

14. The pressurization system for the raw material gas according to claim 1, wherein: Silencers are respectively arranged on the inlet and outlet of the pressurizer.

15. The pressurization system for the raw material gas according to claim 1, characterized in that: The inner cavity of the gas-liquid separator is cylindrical, and the gas-liquid mixture after being pressurized by the pressurizer enters the inner cavity along the tangential direction of the inner cavity.

16. A control method for a raw gas pressurization system, characterized in that: Provided is a pressurization system for a raw material gas as described in any one of claims 1 to 15. The raw material gas and the coolant are pressurized and mixed in the pressurizer to form a gas-liquid mixture. The gas-liquid mixture enters the gas-liquid separator through the first heat exchange channel for gas-liquid separation. The raw material gas after gas-liquid separation is transported outwards through the second heat exchange channel. The gas-liquid mixture in the first heat exchange channel exchanges heat with the raw material gas in the second heat exchange channel.

17. The control method of the raw gas pressurization system according to claim 16, characterized in that: Part of the coolant after gas-liquid separation returns to the inlet of the pressurizer.

18. The control method of the raw gas pressurization system according to claim 16, characterized in that: Part of the raw material gas transported outwards returns to the inlet of the pressurizer.

19. The control method of the raw material gas pressurization system according to claim 16, wherein: Countercurrent heat exchange occurs between the first heat exchange channel and the second heat exchange channel of the heat recovery device.

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