Solid powder pump pressurized entrained-flow bed gasification system

Abstract

The utility model discloses a solid powder pump pressurized entrained-flow bed gasification system. The solid powder pump pressurized entrained-flow bed gasification system comprises a preparation unit, a solid powder pump and a gasification furnace. The preparation unit is used for preparing and storing powder, and the powder is stored in the form of a gas-solid mixture. The gasifier includes an inlet and an outlet. The solid powder pump is connected between the preparation unit and an inlet of the gasification furnace through a feeding channel and is used for continuously pressurizing and conveying powder of the preparation unit to the gasification furnace through the solid powder pump. The gasification furnace converts powder into crude synthesis gas through gasification reaction and discharges the crude synthesis gas from an outlet, compared with a traditional entrained-flow bed gasification system, the structure is simplified, tedious locking hopper pressurization and pressure relief operation steps of a powder conveying system are omitted, solid powder conveying continuity is guaranteed, the working efficiency of the entrained-flow bed gasification system is improved, and the entrained-flow bed gasification system is suitable for industrial production. And meanwhile, gas resources are saved.

Description

Technical Field

[0001] This utility model relates to the field of fluidized bed gasification technology, specifically to a solid powder pump pressurized fluidized bed gasification system. Background Technology

[0002] With the development of clean energy and green chemical technologies, gasification processes are receiving increasing attention as an important way to efficiently utilize solid fuels such as coal and biomass. Fluidized bed gasification, with its high reaction efficiency, good material mixing, and low operating temperature, has become the preferred choice for many industrial gasification applications and is widely used in chemical, power, and urban gas sectors. However, existing fluidized bed gasification processes still face many technical bottlenecks in the transportation and pressurization of solid feedstocks, limiting the efficiency and flexibility of the gasification process.

[0003] In traditional fluidized bed gasification systems, solid feedstocks are fed into the gasifier via a pneumatic conveying system. This system typically includes an atmospheric pulverized coal storage silo, a pulverized coal lock hopper, and a feeding tank (discharge tank). The process involves pneumatically conveying qualified pulverized coal from the pulverized coal preparation system into the atmospheric pulverized coal storage silo. The pulverized coal from the storage silo is then fed into the feeding tank via the pulverized coal lock hopper according to a specific sequential control process. The pulverized coal is fed into the gasifier to participate in the reaction by controlling the pressure difference between the feeding tank and the gasifier. The sequential control process of the pulverized coal lock hopper generally includes four cyclical steps: feeding, pressurizing, discharging, and depressurizing. Specifically, first, the channel between the feeding tank and the pulverized coal lock hopper is closed. After depressurizing the pulverized coal lock hopper, the channel between the atmospheric pulverized coal storage silo and the pulverized coal lock hopper is opened. The channel is opened, and the pulverized coal in the pulverized coal lock hopper is conveyed to the hopper by gravity. Then, the channel between the atmospheric pressure pulverized coal silo and the pulverized coal lock hopper is closed, and the pulverized coal lock hopper is pressurized. After the internal pressure of the pulverized coal lock hopper meets the requirements, the channel between the pulverized coal lock hopper and the feeding tank is opened. The pressure difference between the pulverized coal lock hopper and the feeding tank is used to force the solid powder into the feeding tank, completing the discharge process. Then, the pressure is released following the above steps, thus completing the pneumatic conveying of solid powder in a cycle. It is evident that traditional fluidized bed gasification systems have complex structures, cumbersome gas conveying and powder control procedures, and cannot guarantee the continuity of solid raw material conveying, resulting in low operating efficiency and significant gas resource consumption. More importantly, traditional fluidized bed gasification conveying, also known as dense phase conveying, has low conveying pressure, typically around 4.0 MPa, leading to high overall energy consumption in most high-pressure synthesis chemical processes. Utility Model Content

[0004] In view of this, the present invention provides a solid powder pump pressurized airflow gasification system to solve the problems of conventional airflow gasification systems having complex structures, cumbersome gas conveying and powder control steps, and the inability to guarantee the continuity of solid raw material conveying, resulting in low working efficiency of the airflow gasification system and the consumption of a large amount of gas resources.

[0005] This utility model provides a solid powder pump pressurized fluidized bed gasification system, comprising:

[0006] A preparation unit for preparing and storing powders, wherein the powders are stored in the form of a gas-solid mixture;

[0007] Gasifier, including inlet and outlet;

[0008] A solid powder pump is connected between the preparation unit and the inlet of the gasifier via a feeding channel, and is adapted to continuously transport the powder from the preparation unit to the gasifier.

[0009] Optionally, the preparation unit includes a grinding device and a powder silo. The grinding device is connected to the inlet of the powder silo via a feeding channel, and the outlet of the powder silo is connected to the feeding channel. The powder prepared by the grinding device is transported to the feeding channel via gas.

[0010] Optionally, the outlet of the powder silo is provided with a second gas pipeline, which is adapted to intermittently introduce loosening gas into the outlet.

[0011] Optionally, a first gas pipeline is connected to the feeding channel to form a first node, the first node being located between the solid powder pump and the gasifier, and the first gas pipeline being adapted to introduce high-pressure gas into the feeding channel.

[0012] Optionally, the gas introduced into the first gas pipeline and the second gas pipeline is one of nitrogen, carbon dioxide, carbon monoxide, hydrogen, methane, superheated steam, or a mixture of two or more of these gases.

[0013] Optionally, the inlet of the gasifier is connected to the feeding channel via a burner. The burner is provided with a first feeding port and a second feeding port. The first feeding port is adapted to introduce spent fuel gas into the burner, and the second feeding port is adapted to introduce medium-pressure oxygen into the burner.

[0014] Optionally, it also includes a cooling unit and a washing unit, which are connected in sequence downstream of the outlet of the gasifier.

[0015] Optionally, the washing unit is a washing tower, which is connected to the quench chamber inlet of the gasifier via a first liquid supply pipeline, and a liquid pump is installed on the first liquid supply pipeline.

[0016] Optionally, the cooling unit is a Venturi desuperheater, the water inlet port of the Venturi desuperheater is connected to the first liquid supply pipeline through the second liquid supply pipeline, and the connection point forms a second node, and the liquid pump is located between the second node and the washing tower.

[0017] Beneficial effects:

[0018] 1. The solid powder pump pressurized fluidized bed gasification system provided by this utility model includes: a preparation unit, a solid powder pump, and a gasifier. The preparation unit is used to prepare and store powder, wherein the powder is stored in the form of a gas-solid mixture. The gasifier includes an inlet and an outlet. The solid powder pump is connected between the preparation unit and the inlet of the gasifier through a feeding channel, suitable for continuously conveying the powder from the preparation unit to the gasifier.

[0019] This invention stores powder in the form of a gas-solid mixture, making the powder fluid. Then, a downstream solid powder pump continuously transports the powder through the inlet to the gasifier. The gasifier converts the powder into crude syngas through a gasification reaction and discharges it from the outlet. Compared with the traditional fluidized bed gasification system, it eliminates the need for single or multiple feed tanks, simplifying the structure and omitting cumbersome operation steps such as feeding, pressurizing, discharging, and depressurizing. This ensures the continuity of solid raw material transportation, improves the working efficiency of the fluidized bed gasification system, and saves gas resources.

[0020] Meanwhile, since the powder is stored in the preparation unit as a gas-solid mixture, and given the fluidity of this mixture, a solid powder pump can transport the powder from the preparation unit to the gasifier for reaction in a dry, dense-phase manner. The solid powder pump can operate at pressures exceeding 6.5 MPa and remains stable even under high temperature and pressure conditions, ensuring the continuity, efficiency, and reliability of the transport process. Furthermore, traditional fluidized bed gasification systems often experience uneven feedstock supply, leading to fluctuations in gasification efficiency or reaction interruptions. In contrast, using a solid powder pump to transport the gas-solid mixture ensures a continuous, stable, and uniform flow of the mixture into the gasifier, thereby guaranteeing the stability of the gasification reaction.

[0021] 2. The solid powder pump pressurized fluidized bed gasification system provided by this utility model includes a grinding device and a powder silo in the preparation unit. The grinding device is connected to the inlet of the powder silo through a feeding channel, and the outlet of the powder silo is connected to a feeding channel. The powder prepared by the grinding device is transported to the feeding channel by gas. The grinding device can grind solid raw materials into powder with a particle size that meets the requirements, and then transport the powder to the powder silo through the feeding channel by gas. The gas-pumped feeding method allows the powder to be stored in the powder silo in the form of a gas-solid mixture, which is convenient for subsequent transfer to the gasifier by the solid powder pump. Compared with traditional elevators, transmission belts, or lifting hoppers, this setting not only simplifies the conveying structure between the grinding device and the powder silo, but also eliminates the need for the subsequent step of converting the powder into a flowable gas-solid mixture.

[0022] 3. The solid powder pump pressurized fluidized bed gasification system provided by this utility model has a second gas pipeline at the outlet of the powder silo. The second gas pipeline is suitable for intermittently introducing loosening gas into the outlet. Since the powder is stored in the powder silo in the form of a gas-solid mixture, and since the bottom of the powder silo is usually designed with a narrow opening, powder agglomeration or accumulation is inevitable at the outlet at the bottom of the powder silo. Therefore, loosening gas can be introduced into the outlet through the second gas pipeline. Loosening gas refers to inert gas introduced into the outlet. Loosening gas can loosen the powder accumulated or agglomerated at the outlet, or blow it to move along the side wall of the bottom of the powder silo, so that the powder returns to the state of a gas-solid mixture, avoids clogging the outlet, and ensures that the downstream solid powder pump can efficiently, continuously and stably transport the powder to the gasifier.

[0023] 4. The solid powder pump pressurized fluidized bed gasification system provided by this utility model has a first gas pipeline connected to the feeding channel to form a first node. The first node is located between the solid powder pump and the gasifier. The first gas pipeline is adapted to introduce high-pressure gas into the feeding channel. When the powder leaves the solid powder pump in the form of a gas-solid mixture and enters the downstream, it can mix with the high-pressure gas and enter the gasifier together with the high-pressure gas. On the one hand, the high-pressure gas can further provide conveying power. On the other hand, the high-pressure gas can be pressurized to ensure that the powder enters the gasifier under high pressure, which further ensures the continuous conveying of the powder and also ensures the gasification efficiency of the powder in the reactor.

[0024] 5. The solid powder pump pressurized fluidized bed gasification system provided by this utility model has a gasifier inlet connected to a feeding channel via a burner. The burner is equipped with a first feeding port and a second feeding port. The first feeding port is suitable for introducing spent fuel gas into the burner, and the second feeding port is suitable for introducing medium-pressure oxygen into the burner. By adding spent fuel gas and medium-pressure oxygen through the first and second feeding ports respectively, the spent fuel gas and medium-pressure oxygen can be mixed and, driven by the gas-solid mixture containing powder, enter the reaction chamber of the gasifier at high speed. Compared with directly introducing spent fuel gas and medium-pressure oxygen into the reaction chamber, this arrangement can ensure uniform mixing of spent fuel gas and medium-pressure oxygen, providing oxidant and heat for the reaction in the reactor and promoting the reaction in the reaction chamber.

[0025] 6. The solid powder pump pressurized fluidized bed gasification system provided by this utility model includes a cooling unit and a washing unit, which are connected sequentially downstream of the gasifier outlet. The cooling unit can cool the crude syngas from the gasifier. The cooled crude syngas enters the washing unit for washing to remove impurities, particulate matter, and some acidic gases. The final output syngas can then be used in subsequent chemical production or fuel utilization stages.

[0026] 7. The solid powder pump pressurized fluidized bed gasification system provided by this utility model has a washing unit as a washing tower. The washing tower is connected to the inlet of the quench chamber of the gasifier through a first liquid supply pipeline, and a liquid pump is installed on the first liquid supply pipeline. The washing tower removes impurities, particulate matter, and some acidic gases from the crude syngas by spraying. The liquid used to wash the crude syngas can be pumped into the inlet of the quench chamber of the gasifier by the liquid pump. The drainage from the quench chamber can cool the slag produced in the gasifier, forming solid coarse slag for subsequent discharge and treatment. The washing liquid in the washing tower is pumped into the quench chamber, reusing the waste liquid and saving water resources.

[0027] 8. The solid powder pump pressurized fluidized bed gasification system provided by this utility model has a Venturi desuperheater as its cooling unit. The water inlet of the Venturi desuperheater is connected to the first liquid supply pipeline through a second liquid supply pipeline, and the connection point forms a second node. The liquid pump is located between the second node and the scrubbing tower. The crude syngas enters the chamber of the Venturi desuperheater and undergoes diffusion and deceleration. The liquid in the second liquid supply pipeline enters the chamber of the Venturi desuperheater through the water inlet and mixes thoroughly with the crude syngas, absorbing the heat in the crude syngas and thus reducing the heat of the crude syngas. Afterward, both are discharged into the scrubbing tower. This arrangement allows for further reuse of the liquid after scrubbing in the scrubbing tower, further saving water resources. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the solid powder pump pressurized airflow gasification system according to an embodiment of the present invention;

[0030] Figure 2 This is a flowchart of the solid powder pump pressurized airflow bed gasification process according to an embodiment of the present invention.

[0031] Explanation of reference numerals in the attached figures:

[0032] 1. Preparation unit; 11. Grinding device; 111. Feeding channel; 112. Solid raw material; 113. Inert gas; 12. Powder silo; 121. Second gas pipeline; 122. Loosening gas; 2. Gasifier; 21. Burner; 211. Spent fuel gas; 212. Medium-pressure oxygen; 22. Slag discharge hopper; 23. Coarse slag; 24. Liquid discharge pipeline; 25. Quenching chamber waste liquid; 3. Solid powder pump; 31. Feeding channel; 32. First gas pipeline; 33. High-pressure gas; 301. First node; 4. Cooling unit; 5. Washing unit; 51. Washing liquid inlet pipe; 61. First liquid supply pipeline; 62. Liquid pump; 63. Second liquid supply pipeline; 601. Second node; 7. Steam drum; 71. Circulating water pump; 72. Boiler feedwater; 73. High-pressure steam; 8. Syngas. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0034] The solid powder pump pressurized fluidized bed gasification system and process provided in this embodiment can be applied to the gasification reaction of combustibles such as pulverized coal, coal powder, and coke powder. The following description uses the treatment of pulverized coal as an example to illustrate the device, structure, and treatment process provided in this embodiment.

[0035] Before introducing the solid powder pump pressurized fluidized bed gasification system and process provided in this embodiment, we will first describe the traditional fluidized bed gasification system. In a traditional fluidized bed gasification system, the step of pressurizing and conveying powder is usually completed by an atmospheric pressure pulverized coal silo, a pulverized coal lock hopper, and a pulverized coal feed tank. The sequence of operation of the atmospheric pressure pulverized coal silo, the pulverized coal lock hopper, and the pulverized coal feed tank must be controlled. Specifically, in the atmospheric pressure pulverized coal silo feeding stage, the channel between the pulverized coal lock hopper and the pulverized coal feed tank needs to be closed, and the channel between the atmospheric pressure pulverized coal silo and the pulverized coal lock hopper needs to be opened. Pulverized coal enters the pulverized coal lock hopper under gravity. Then, high-pressure carbon dioxide or nitrogen is introduced into the pulverized coal lock hopper for pressurization. After the pressure inside the pulverized coal lock hopper reaches the specified value, the pulverized coal lock hopper and the pulverized coal feed tank are closed. The channel between the pulverized coal hoppers is opened, and under the pressure difference, the pulverized coal in the pulverized coal lock hopper enters the pulverized coal feed hopper. Then, the channel between the pulverized coal lock hopper and the pulverized coal feed hopper is closed, and the pulverized coal lock hopper is depressurized to ensure that the next batch of pulverized coal can enter the pulverized coal lock hopper under the action of gravity. This completes one pulverized coal conveying cycle. It can be seen that the transmission-based pulverized coal conveying method is not only structurally complex, but also requires complex sequence control to operate. Moreover, its conveying process cannot be carried out continuously, resulting in low gasification reaction efficiency. Furthermore, the frequent depressurization of the pulverized coal lock hopper and the pulverized coal feed hopper wastes a lot of gas resources. Although some technical improvements have increased the number of pulverized coal feed hoppers, the inherent problems of non-continuous pulverized coal conveying and waste of gas resources have not been solved.

[0036] like Figure 1 As shown, in order to solve the above problems, this embodiment provides a solid powder pump pressurized fluidized bed gasification system, including: a preparation unit 1, a gasification furnace 2 and a solid powder pump 3.

[0037] Preparation unit 1 is used to prepare and store powder, wherein the powder is stored in the form of a gas-solid mixture, and the powder may be pulverized coal.

[0038] The gasifier 2 includes an inlet and an outlet. The gasifier 2 also includes a reaction chamber, a quench chamber and a slag discharge port. The reaction chamber is the main place for the gasification reaction of pulverized coal. The quench chamber is used to cool the molten slag after the pulverized coal reaction. The slag discharge port is used to discharge the molten slag for subsequent processing. For example, a slag discharge lock hopper 22 can be set downstream of the slag discharge port to discharge coarse slag 23.

[0039] The solid powder pump 3 is connected between the preparation unit 1 and the inlet of the gasifier 2 through the feeding channel 31. It is suitable for continuously conveying the powder from the preparation unit 1 to the gasifier 2. That is, the solid powder pump 3 continuously conveys the gas-solid mixture to the inlet of the gasifier 2 in a form similar to fluid conveying, ensuring that the reaction of the powder in the gasifier can proceed continuously and improving the gasification efficiency.

[0040] In this embodiment, the powder is stored in the form of a gas-solid mixture, which makes the powder fluid. Then, the powder is continuously transported to the gasifier 2 through the inlet by the downstream solid powder pump 3. The gasifier 2 converts the powder into crude syngas through a gasification reaction and discharges it from the outlet. Compared with the traditional fluidized bed gasification system, there is no need to set up one or more feed tanks, which simplifies the structure and eliminates cumbersome operation steps such as feeding, pressurizing, discharging and depressurizing. This ensures the continuity of solid raw material 112 transportation and improves the working efficiency of the fluidized bed gasification system. In this embodiment, the solid powder pump 3 does not need to perform frequent depressurization operations, thereby saving gas resources.

[0041] Meanwhile, since the powder is stored in the preparation unit 1 in the form of a gas-solid mixture, and given the fluidity of the gas-solid mixture, the powder in the preparation unit 1 can be transported to the gasifier 2 for reaction in a dry powder dense phase conveying manner by a solid powder pump. The solid powder pump can carry out the conveying at a high pressure of over 6.5 MPa, and can also operate stably in high temperature and high pressure environments, ensuring the continuity, efficiency and reliability of the conveying process.

[0042] In addition, the feeding tank of the traditional fluidized bed gasification system will have the problem of uneven raw material supply, which will lead to fluctuations in gasification efficiency or interruption of reaction. In contrast, the method of conveying gas-solid mixture by solid powder pump can ensure that the gas-solid mixture enters the gasifier 2 continuously, stably and uniformly, thereby ensuring the stability of gasification reaction.

[0043] The solid powder pump in this embodiment can be a rotary valve type, screw type, or dual-chamber type positive displacement pump, which transports a gas-solid mixture containing powder by changing the internal volume of the pump cylinder of the above positive displacement pump.

[0044] For example, rotary valve positive displacement pumps mainly utilize rotary valves to control the entry and conveying of powder. Their core conveying method involves conveying powder via rotating blades, relying on pneumatic or gravity force for transport. During the feeding stage, powder enters the feed chamber of the rotary valve from the powder silo 12 or hopper. The rotary valve blades rotate, gradually filling the blade slots with powder. During the conveying stage, the rotary valve blades rotate, gradually feeding the powder into the conveying pipeline. During the discharging stage, the powder at the rotary valve outlet enters the feeding channel 31 and then into the gasifier 2.

[0045] The spiral positive displacement pump uses rotating spiral blades to propel powder along a pipeline, similar to a mechanical conveying method. During the feeding stage, powder falls from the powder hopper 12 into the spiral conveying chamber and enters the conveying channel by gravity or auxiliary airflow. During the conveying stage, the spiral blades rotate, and the powder moves between the blades, being pushed towards the discharge port. The powder conveying rate can be controlled by adjusting the rotational speed of the spiral blades. In the discharge stage, the powder is pushed into the feeding channel 31 and then enters the gasifier 2.

[0046] The dual-chamber positive displacement pump uses two alternating conveying chambers to deliver powder under high pressure in a pulsed manner, ensuring a stable supply of powder. During the feeding stage, powder enters the first conveying chamber from the powder silo 12, and the discharge valve is closed to prevent leakage. Simultaneously, powder from the previous filling is being conveyed outwards through the second conveying chamber. During the pressurized conveying stage, the pressure in the first conveying chamber gradually increases. Once the set value is reached, the discharge valve opens, and the powder is pushed into the conveying pipeline under high pressure. At the same time, the second conveying chamber begins feeding to ensure continuous conveying. This cycle repeats, alternating between the two chambers. After the first chamber finishes discharging, it enters the refeeding stage, while the second chamber enters the pressurized conveying stage. The two chambers operate alternately to ensure uninterrupted powder delivery. The second conveying chamber delivers the powder to the feeding channel 31, and then into the gasifier 2.

[0047] To clearly illustrate the advantages of using a solid powder pump to transport powder in this embodiment, the applicant used solid powder pump transport as the experimental group and traditional gas pressurized transport as the control group, using the transport medium requirements and resource consumption during the working process as reference data, and obtained the following experimental data:

[0048]

[0049] In the gasification reaction, the higher the gasification pressure, the higher the reaction efficiency. This experiment mainly uses two reaction pressures, 4.0 MPa and 6.5 MPa, as examples to illustrate the process.

[0050] When the gasification pressure is 4.0 MPa, the oxygen pressure requirement inside gasifier 2 is 5.2 MPa. In the upstream conveying stage, when using a solid powder pump, the inert gas pressure requirement is 5.4 MPa. Taking carbon dioxide (CO2) as an example, the compression work of the inert gas is less than or equal to 1300 kW, so no inert gas emission is required, and the investment is less than 20 million yuan. When using traditional gas pressurization for conveying, the inert gas pressure requirement is greater than or equal to 7.3 MPa. At least 15000 Nm3 / h of CO2 needs to be pressurized to 7.3 MPa, and the compression work of the inert gas is 2600 kW. Due to the need for depressurization, the inert gas emission is greater than 10000 Nm3 / h, and an additional 2200 kW of gas compression work is required, resulting in an investment greater than 85 million yuan.

[0051] When the gasification pressure is 6.5 MPa, the required oxygen pressure inside gasifier 2 is 7.7 MPa. In the upstream conveying stage, when using a solid powder pump, the required inert gas pressure is 7.9 MPa. Taking carbon dioxide (CO2) as an example, the compression work of the inert gas is less than or equal to 1600 kW, so no inert gas emissions are required, and the investment is less than 30 million yuan. When using traditional gas pressurization for conveying, the required inert gas pressure is greater than or equal to 9.0 MPa, and the compression work is 3100 kW. Due to the need for depressurization, the inert gas emission is greater than 11000 Nm3 / h, and an additional 2200 kW of gas compression work is required, resulting in an investment greater than 85 million yuan.

[0052] Therefore, it can be seen that using solid powder pumps for transportation can not only save more than 50% of power consumption, but also reduce gas consumption and investment costs.

[0053] Considering that the gasification reaction of the powder in gasifier 2 requires high pressure, such as Figure 1 As shown, in this embodiment, a first gas pipeline 32 is connected to the feeding channel 31 to form a first node 301. The first node 301 is located between the solid powder pump and the gasifier 2. The first gas pipeline 32 is adapted to introduce high-pressure gas 33 into the feeding channel 31. The high-pressure gas 33 can be high-pressure nitrogen or high-pressure carbon dioxide gas. When the powder leaves the solid powder pump in the form of a gas-solid mixture and enters the downstream, it can mix with the high-pressure gas 33 and enter the gasifier 2 together with the high-pressure gas 33. On the one hand, the high-pressure gas 33 can further provide conveying power. On the other hand, the high-pressure gas 33 can be pressurized to ensure that the powder enters the gasifier 2 under high pressure, which further ensures the continuous conveying of the powder and also ensures the gasification efficiency of the powder in the reactor.

[0054] like Figure 1 As shown, in this embodiment, the preparation unit 1 includes a grinding device 11 and a powder silo 12. The grinding device 11 is connected to the inlet of the powder silo 12 through a feeding channel 111, and the outlet of the powder silo 12 is connected to a feeding channel 31. The powder prepared by the grinding device 11 is transported to the feeding channel 111 by gas. For example, the grinding device 11 is provided with a feeding port for adding solid raw materials 112. The outlet of the grinding device 11 is provided with an air inlet connected to an external gas pipeline. The gas pipeline is suitable for introducing low-pressure inert gas such as low-pressure nitrogen. Low-pressure nitrogen will not react with the powder and can also drive the powder through the feeding channel 111 into the powder silo, where it mixes with the powder to form a gas-solid mixture and is stored together in the powder silo 12.

[0055] The specific form of the grinding device 11 is not limited, and it may include a grinding structure and a screen structure. The grinding structure grinds the solid raw material, and the screen structure filters the raw material with a larger particle size. For example, a 200-mesh screen can be used for the screen structure. In this way, the grinding device 11 grinds the solid raw material 112 into powder with the required particle size. Then, the powder is transported to the powder silo 12 through the feeding channel 111 by gas conveying. The gas conveying method allows the powder to be stored in the powder silo 12 in the form of a gas-solid mixture, so that the powder can be transferred to the gasifier 2 by the solid powder pump later. Compared with the traditional elevator, transmission belt or lifting hopper, this setting not only simplifies the conveying structure between the grinding device 11 and the powder silo 12, but also eliminates the step of converting the powder into a flowable gas-solid mixture.

[0056] Considering that some powder will inevitably settle in powder silo 12, such as Figure 1 As shown, in this embodiment, the outlet of the powder silo 12 is provided with a second gas pipeline 121. The second gas pipeline 121 is adapted to intermittently introduce loosening gas 122 into the outlet. The loosening gas 122 can be low-pressure nitrogen.

[0057] Since the powder is stored in the powder silo 12 in the form of a gas-solid mixture, and since the bottom of the powder silo 12 is usually designed with a narrow opening, after the gas-solid mixture in the powder silo 12 settles, powder will inevitably clump or accumulate at the discharge port at the bottom of the powder silo 12. Therefore, loosening gas 122 can be intermittently introduced into the discharge port through the second gas pipeline 121. For example, a loosening gas 122 introduction cycle can be set. The loosening gas 122 can loosen the powder that has accumulated or clumped at the discharge port, or blow it to move along the side wall at the bottom of the powder silo 12, so that the powder returns to the state of a gas-solid mixture, avoids clogging the discharge port, and ensures that the downstream solid powder pump can efficiently, continuously and stably transport the powder to the gasifier 2.

[0058] In this embodiment, the gas introduced into the first gas pipeline 32 and the second gas pipeline 121 is one of nitrogen, carbon dioxide, carbon monoxide, hydrogen, methane and superheated steam, or a mixture of two or more of these gases. The methane can be natural gas or coal gas.

[0059] like Figure 1As shown, in this embodiment, the inlet of the gasifier 2 is connected to the feeding channel 31 via a burner 21. The burner 21 is provided with a first feeding port and a second feeding port. The burner 21 can be an industrial burner. The first feeding port is suitable for introducing spent fuel gas 211 into the burner 21, and the second feeding port is suitable for introducing medium-pressure oxygen 212 into the burner 21. By adding spent fuel gas 211 and medium-pressure oxygen 212 through the first and second feeding ports respectively, the spent fuel gas 211 and medium-pressure oxygen 212 can be mixed and, driven by the gas-solid mixture containing powder, enter the reaction chamber of the gasifier 2 at high speed. Compared with directly introducing spent fuel gas 211 and medium-pressure oxygen 212 into the reaction chamber, this arrangement can ensure that the spent fuel gas 211 and medium-pressure oxygen 212 are uniformly mixed, providing oxidant and heat for the reaction in the reactor and promoting the reaction in the reaction chamber. Both spent fuel gas 211 and medium-pressure oxygen 212 can be used as oxidants. This setup allows for the reuse of spent fuel gas 211, further conserving resources.

[0060] like Figure 1 As shown, in this embodiment, the solid powder pump pressurized fluidized bed gasification system also includes a cooling unit 4 and a washing unit 5, which are connected in sequence downstream of the outlet of the gasifier 2.

[0061] Cooling unit 4 can cool the crude syngas from gasifier 2. The cooled crude syngas enters washing unit 5 for washing to remove impurities, particulate matter and some acidic gases. The final output syngas can enter the subsequent chemical production or fuel utilization stage.

[0062] like Figure 1 As shown, in one embodiment of this example, the washing unit 5 is a washing tower, which is connected to the quench chamber inlet of the gasifier 2 via a first liquid supply pipeline 61. A liquid pump 62 is installed on the first liquid supply pipeline 61. Alternatively, the washing unit 5 can also be a packed tower.

[0063] The scrubbing tower is equipped with a scrubbing liquid inlet pipe 51, which supplies water to the atomizing nozzles inside the scrubbing tower. The atomizing nozzles remove impurities, particulate matter, and some acidic gases from the crude syngas through spraying. After scrubbing, the crude syngas can be used as syngas 8 for downstream processes. Furthermore, the liquid from scrubbing the crude syngas can be pumped into the quench chamber inlet of the gasifier 2 via a liquid pump 62. The quench chamber drainage cools the slag produced in the gasifier 2, forming solid coarse slag for subsequent discharge. By pumping the scrubbing liquid from the scrubbing tower into the quench chamber via the liquid pump 62, the waste liquid is reused, saving water resources.

[0064] In this embodiment, the outlet of the quench chamber is connected to a drain pipe 24, which is used to discharge the waste liquid 25 from the quench chamber. The waste liquid 25 from the quench chamber can be reused after treatment processes such as sedimentation and filtration.

[0065] like Figure 1 As shown, in one embodiment of this invention, the cooling unit 4 is a Venturi desuperheater. The water inlet port of the Venturi desuperheater is connected to the first liquid supply pipe 61 through the second liquid supply pipe 63, and the connection point forms a second node 601. The liquid pump 62 is located between the second node 601 and the scrubbing tower. The crude syngas enters the chamber of the Venturi desuperheater and undergoes diffusion and deceleration. The liquid in the second liquid supply pipe 63 enters the chamber of the Venturi desuperheater through the water inlet port and mixes thoroughly with the crude syngas, absorbing the heat in the crude syngas and thus reducing the heat of the crude syngas. Afterward, the liquid is discharged into the scrubbing tower. This arrangement allows for further reuse of the liquid after scrubbing in the scrubbing tower, further saving water resources. As an alternative implementation, the cooling unit 4 can also be a cooling tower.

[0066] like Figure 1 As shown, in this embodiment, the gasifier 2 may further include a jacket, which adopts a water-cooled wall structure and contains flowing water or steam. While protecting the furnace chamber, the generated steam can also be used to heat the outside environment, improving resource utilization. Alternatively, the gasifier 2 may not have a jacket.

[0067] like Figure 1 As shown, in one embodiment of this example, the jacket of the gasifier 2 is provided with a liquid inlet and a steam outlet. The solid powder pump pressurized fluidized bed gasification system also includes a steam drum 7. The riser pipe of the steam drum 7 is connected to the steam outlet of the gasifier 2, and the downcomer pipe of the steam drum 7 is connected to the liquid inlet of the gasifier. A circulation pump can be installed on the downcomer pipe. The steam drum 7 is also provided with a high-pressure steam outlet pipe and a boiler feedwater inlet pipe. The boiler feedwater 72 enters the steam drum 7 through the boiler feedwater inlet pipe, and then enters the jacket of the gasifier 2 through the downcomer pipe. The water vapor in the jacket of the gasifier 2 enters the steam drum 7 through the riser pipe, and becomes high-pressure steam 73 after superheating and is discharged from the high-pressure steam outlet pipe. The high-pressure steam 73 can be used to provide heat to the outside or to perform thermal work to improve resource utilization.

[0068] like Figure 2 As shown, this embodiment provides a solid powder pump pressurized fluidized bed gasification process for the aforementioned solid powder pump pressurized fluidized bed gasification system. The solid powder pump pressurized fluidized bed gasification process includes:

[0069] Step S1: Preparation unit 1 prepares and stores powder. Preparation unit 1 includes a grinding device 11 and a powder silo 12. The grinding device 11 is connected to the inlet of the powder silo 12 through a feeding channel 111, and the outlet of the powder silo 12 is connected to a feeding channel 31. The powder prepared by the grinding device 11 is transported to the feeding channel 111 by gas.

[0070] Step S2: Solid powder pump 3 continuously pressurizes and transports the powder in preparation unit 1 to gasifier 2.

[0071] Step S3: Gasifier 2 converts the powder into crude syngas through a gasification reaction. The inlet of gasifier 2 is connected to the feeding channel 31 via burner 21. The side wall of burner 21 is provided with a first feeding port and a second feeding port. The first feeding port is suitable for introducing spent fuel gas 211 into burner 21, and the second feeding port is suitable for introducing medium-pressure oxygen 212 into burner 21. By adding spent fuel gas 211 and medium-pressure oxygen 212 through the first and second feeding ports respectively, the spent fuel gas 211 and medium-pressure oxygen 212 can be mixed and, driven by the gas-solid mixture containing powder, enter the reaction chamber of gasifier 2 at high speed. Compared with directly introducing spent fuel gas 211 and medium-pressure oxygen 212 into the reaction chamber, this arrangement can ensure that the spent fuel gas 211 and medium-pressure oxygen 212 are uniformly mixed, providing oxidant and heat for the reaction in the reactor, promoting the reaction in the reaction chamber, and generating crude syngas from the powder through a gasification reaction in the reaction chamber.

[0072] In addition to the steps mentioned above, it also includes:

[0073] Cooling unit 4 cools the crude syngas and sends it to washing unit 5. Cooling unit 4 is a Venturi desuperheater.

[0074] Washing unit 5 washes the cooled crude syngas to obtain syngas 8. Washing unit 5 is a washing tower.

[0075] The above process flow was described concurrently with the introduction of the solid powder pump pressurized fluidized bed gasification system above. Those skilled in the art can understand the beneficial effects of using a solid powder pump to transport powder from the above description, so it will not be repeated here.

[0076] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A solid powder pump pressurized fluidized bed gasification system, characterized in that, include: Preparation unit (1) is used to prepare and store powder, wherein the powder is stored in the form of a gas-solid mixture; Gasifier (2), including inlet and outlet; A solid powder pump (3) is connected between the inlet of the preparation unit (1) and the gasifier (2) via a feeding channel (31), and is adapted to continuously pressurize and transport the powder from the preparation unit (1) to the gasifier (2).

2. The solid powder pump pressurized fluidized bed gasification system according to claim 1, characterized in that, The preparation unit (1) includes a grinding device (11) and a powder silo (12). The grinding device (11) is connected to the inlet of the powder silo (12) through a feeding channel (111). The outlet of the powder silo (12) is connected to the feeding channel (31). The powder prepared by the grinding device (11) is transported to the feeding channel (111) by gas.

3. The solid powder pump pressurized fluidized bed gasification system according to claim 2, characterized in that, The outlet of the powder silo (12) is provided with a second gas pipeline (121), which is adapted to intermittently introduce loosening gas (122) into the outlet.

4. The solid powder pump pressurized fluidized bed gasification system according to claim 3, characterized in that, The feeding channel (31) is connected to a first gas pipeline (32), and the connection point between the feeding channel (31) and the first gas pipeline (32) forms a first node (301). The first node (301) is located between the solid powder pump (3) and the gasifier (2). The first gas pipeline (32) is adapted to introduce high-pressure gas (33) into the feeding channel (31).

5. The solid powder pump pressurized fluidized bed gasification system according to claim 4, characterized in that, The gas introduced into the first gas pipeline (32) and the second gas pipeline (121) is one of nitrogen, carbon dioxide, carbon monoxide, hydrogen, methane and superheated steam, or a mixture of two or more of these gases.

6. The solid powder pump pressurized fluidized bed gasification system according to claim 1, characterized in that, The inlet of the gasifier (2) is connected to the feeding channel (31) through the burner (21). The burner (21) is provided with a first feeding port and a second feeding port. The first feeding port is suitable for feeding spent fuel gas (211) into the burner (21), and the second feeding port is suitable for feeding medium-pressure oxygen (212) into the burner (21).

7. The solid powder pump pressurized fluidized bed gasification system according to claim 1 or 2, characterized in that, It also includes a cooling unit (4) and a washing unit (5), which are connected in sequence downstream of the outlet of the gasifier (2).

8. The solid powder pump pressurized fluidized bed gasification system according to claim 7, characterized in that, The washing unit (5) is a washing tower. The washing tower is connected to the quench chamber inlet of the gasifier (2) through the first liquid supply pipeline (61). A liquid pump (62) is installed on the first liquid supply pipeline (61).

9. The solid powder pump pressurized fluidized bed gasification system according to claim 8, characterized in that, The cooling unit (4) is a Venturi desuperheater. The water inlet port of the Venturi desuperheater is connected to the first liquid supply pipeline (61) through the second liquid supply pipeline (63), and the connection point forms a second node (601). The liquid pump (62) is located between the second node (601) and the washing tower.

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