Crude coal gas shift system and process for preparing synthesis gas by using the same

Abstract

The present application provides a crude coal gas shift system and a process for preparing synthesis gas by using the same. The crude coal gas shift system comprises a shift device, a first waste heat boiler, a detoxification tank, a second waste heat boiler and a heat exchange device. The shift device has an inlet and an outlet, and the inlet of the shift device is connected with a crude coal gas source. The first waste heat boiler has an inlet and an outlet, and the inlet of the first waste heat boiler is connected with the crude coal gas source. The detoxification tank has an inlet and an outlet, and the inlet of the detoxification tank is connected with the outlet of the first waste heat boiler. The second waste heat boiler has an inlet and an outlet, and the inlet of the second waste heat boiler is connected with the outlet of the detoxification tank. The heat exchange device has an inlet and an outlet, and the inlet of the heat exchange device is connected with the outlet of the second waste heat boiler. In the direction from the inlet to the outlet of the detoxification tank, the detoxification tank comprises a first region and a second region which are communicated in sequence, the first region is filled with a hydrolysis agent, and the second region is filled with a shift catalyst. The above shift system can realize high load production of more than 100%.

Description

Technical Field

[0001] This invention relates to the field of coal chemical technology, and more specifically, to a crude coal gas conversion system and a process for producing syngas using the same. Background Technology

[0002] Currently, most coal chemical processes utilize coal gasification to produce syngas. This syngas then undergoes shift conversion and purification processes before being fed into the synthesis unit to produce chemical products such as natural gas, olefins, methanol, and petroleum products. Water-gas shift conversion is an indispensable process in coal chemical engineering, its main function being to adjust the hydrogen-to-carbon ratio of the syngas. The principle of the shift reaction is that under certain pressure and temperature conditions, and with the action of a catalyst, CO and H₂O(g) in the process gas undergo a shift reaction to produce H₂ and CO₂.

[0003] The reaction formula is as follows:

[0004] CO+H2O=CO2+H2+Q△H=-41.1kJ / mol

[0005] Q = 10861 - 1.44T - 0.4 × 10⁻⁴T 2 +8×18-8T 3

[0006] Since shift reactions can reduce the carbon monoxide content in syngas and generate more H2, they can not only adjust the hydrogen-to-carbon ratio but also meet different production requirements. Therefore, water-gas shift reactions are crucial for downstream industrial synthesis.

[0007] In modern large-scale coal chemical plants, the shift conversion unit is divided into a shift system and a non-shift system. The shift system is equipped with a shift furnace, which is where carbon monoxide reacts with steam. The shift furnace contains a sulfur-resistant shift catalyst. The non-shift system is equipped with a detoxification tank, which contains a hydrolyzing agent. Its main purpose is to remove carbonyl sulfur and other organic sulfur from the crude coal gas. The non-shift system does not involve the carbon monoxide shift reaction.

[0008] However, during production, if the process is not changed and the gas volume of the conversion system and the non-conversion system is directly increased, the conversion unit can only maintain 100% full-load operation at most, and the load cannot be further increased. In addition, directly increasing the load will increase the pressure drop of the conversion unit, exceeding the design value, and the increased system pressure may lead to the venting of syngas from the gasification section. Summary of the Invention

[0009] The main objective of this invention is to provide a crude gas conversion system and a process for producing syngas using the same, in order to solve the problem in the prior art that it is difficult to increase the load of the conversion device to above 100%.

[0010] To achieve the above objectives, according to one aspect of the present invention, a crude gas conversion system is provided, comprising: a conversion device, a first waste heat boiler, a detoxification tank, a second waste heat boiler, and heat exchange equipment. The conversion device has a conversion device inlet and a conversion device outlet, the conversion device inlet being connected to a crude gas source, and the conversion device is used to perform a first conversion reaction on a portion of the crude gas to obtain first converted gas. The first waste heat boiler has a first waste heat boiler inlet and a first waste heat boiler outlet, the first waste heat boiler inlet being connected to a crude gas source, and the first waste heat boiler is used to perform a first condensation on the remaining portion of the crude gas to obtain condensed crude gas. The detoxification tank has a detoxification tank inlet and a detoxification tank outlet, the detoxification tank inlet being connected to the outlet of the first waste heat boiler, and the detoxification tank is used to perform a first condensation reaction on the condensed crude gas. The second conversion reaction yields detoxified gas, comprising unconverted gas and converted gas; a second waste heat boiler has a second waste heat boiler inlet and a second waste heat boiler outlet, the inlet of which is connected to the outlet of the detoxification tank, and is used for second condensation of the detoxified gas to obtain condensed gas; a heat exchanger has a heat exchanger inlet and a heat exchanger outlet, the inlet of which is connected to the outlet of the second waste heat boiler, and is used for heat exchange of the condensed gas to obtain unconverted gas and second converted gas; the first converted gas, unconverted gas, and second converted gas are fed into a syngas unit to prepare syngas; wherein, along the direction from the inlet to the outlet of the detoxification tank, the detoxification tank includes a first region and a second region connected in sequence, the first region being filled with a hydrolyzing agent, and the second region being filled with a conversion catalyst.

[0011] Furthermore, the inlet temperature of the detoxification tank is 200-230°C; and / or, when the load of the conversion device is greater than 80%, the detoxification tank includes one or multiple detoxification tanks arranged in parallel, preferably two detoxification tanks arranged in parallel, and each detoxification tank can be switched.

[0012] Furthermore, the crude gas conversion system also includes a new waste heat boiler, which is connected in parallel with a second waste heat boiler; and / or, the inner diameter of the inlet pipeline of the second waste heat boiler is 105-115 cm, and the inner diameter of the outlet pipeline of the second waste heat boiler is 95-105 cm; and / or, the temperature of the second waste heat boiler is 240-260℃, and / or, the pressure of the second waste heat boiler is 3.6-4.5 MPa; and / or, the inner diameter of the inlet pipeline of the new waste heat boiler is 100-110 cm, and the inner diameter of the outlet pipeline of the new waste heat boiler is 90-100 cm.

[0013] Furthermore, the inner diameter of the inlet pipe of the first waste heat boiler is 120-135 cm, and the inner diameter of the outlet pipe of the first waste heat boiler is 110-122 cm; and / or, the temperature of the first waste heat boiler is 200-220℃, and / or, the pressure of the first waste heat boiler is 4-4.4 MPa.

[0014] Furthermore, the temperature of the conversion device is 200–460°C, and / or the pressure of the conversion device is 3.6–4.4 MPa; and / or the water-to-gas ratio of the first conversion gas is 0.3–0.65:1.

[0015] Furthermore, the inlet temperature of the heat exchanger is 240–260°C, and / or the outlet temperature of the heat exchanger is 30–60°C; and / or the water-to-gas ratio of the unconverted gas is 0.4–0.8:1; and / or the water-to-gas ratio of the second converted gas is 0.35–0.7:1.

[0016] According to one aspect of the present invention, a process for producing syngas using the above-described crude gas shift system is provided. The process includes: crude gas consisting of a portion of crude gas and a remaining portion of crude gas; subjecting the portion of crude gas to a first shift reaction to obtain a first shift gas; subjecting the remaining portion of crude gas to a first condensation to obtain condensed crude gas; subjecting the condensed crude gas to a second shift reaction under the action of a shift catalyst and a hydrolysant to obtain detoxified gas comprising detoxified unshifted gas and detoxified shifted gas; subjecting the detoxified gas to a second condensation to obtain condensed gas; subjecting the condensed gas to heat exchange to obtain unshifted gas and second shift gas; and using the first shift gas, unshifted gas, and second shift gas as raw materials for syngas.

[0017] Furthermore, the volume ratio of the aforementioned portion of crude gas to the remaining portion of crude gas is 3-4:2-3, and / or the water-to-gas ratio of the crude gas is 0.6-0.85:1, and / or the volume ratio of the first shift gas, the detoxified but not shifted gas, and the detoxified shift gas is 4-6:2-3:2-3.

[0018] Furthermore, relative to 50,000–100,000m 3 The volume of the shift catalyst in the condensed crude gas is 10–20 m³. 3 The volume of the hydrolysate is 10–18 m³. 3 The volume ratio of hydrolysant to shift catalyst is 1 to 1.3:1; and / or the shift catalyst is selected from any one or more of iron-chromium shift catalysts, copper-zinc shift catalysts, and cobalt-molybdenum shift catalysts; and / or the active component of the hydrolysant is an alkali metal.

[0019] Furthermore, the temperature of the first shift reaction is 250–450 °C; and / or, the space velocity of the first shift reaction is 4500–6500 h⁻¹. -1 ; and / or, the temperature of the second shift reaction is 230–460 °C; and / or, the space velocity of the second shift reaction is 2000–3000 h⁻¹. -1 .

[0020] By applying the technical solution of this invention, this application, through filling a shift catalyst in the detoxification tank, allows the unshifted gas (i.e., condensed crude gas) to undergo a partial shift reaction. This reduces the gas distribution ratio of the shift converter, thereby lowering the pressure drop of the shift converter and further increasing the load of the crude gas shift system, achieving a load exceeding 100%, or even as high as 110%. Specifically, a portion of the crude gas undergoes a first shift reaction in the shift converter to obtain shifted gas; the remaining portion undergoes first condensation in a first waste heat boiler. This not only regulates the temperature of the crude gas to meet the temperature requirements of the subsequent second shift reaction, preventing the shift catalyst in the detoxification tank from deactivating due to excessive temperature, but also removes impurities from the crude gas. By filling the detoxification tank with a hydrolysate and a shift catalyst in the above manner, the composition of the condensed crude gas can be pre-adjusted under the action of the hydrolysate, optimizing the conditions for the second shift reaction. This facilitates the second shift reaction of CO and H2O in the condensed crude gas under the action of the shift catalyst, improving the reaction efficiency of the second shift reaction, thereby reducing the gas distribution ratio of the shift converter and lowering the pressure drop of the shift converter. Simultaneously, the hydrolysant can remove carbonyl sulfur and other organic sulfur from the condensed crude coal gas. The detoxified gas undergoes a second condensation in the second waste heat boiler, which not only separates the water vapor produced by the second shift reaction, thus reducing the moisture content in the gas, but also regulates the gas temperature. Further heat exchange in the condensed gas equipment further reduces the gas temperature to meet the requirements of subsequent synthesis processes. Passing the aforementioned first shift gas, unshifted gas, and second shift gas into the syngas unit can produce high-quality syngas, thereby obtaining high-quality chemical products. Attached Figure Description

[0021] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0022] Figure 1 A schematic diagram of the crude gas conversion system of this application is shown.

[0023] The above figures include the following reference numerals:

[0024] 1. Conversion device; 2. First waste heat boiler; 3. Detoxification tank; 4. Second waste heat boiler; 5. Heat exchange equipment; 6. Newly added waste heat boiler; 31. First detoxification tank; 32. Second detoxification tank. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] As analyzed in the background section of this application, there is a problem in the prior art that it is difficult to increase the load of the conversion device to above 100%. In order to solve the above problems, this application provides a crude gas conversion system and a process for producing syngas using it.

[0027] In a typical embodiment of this application, a crude gas conversion system is provided, such as... Figure 1 As shown, the crude gas conversion system includes: a conversion device 1, a first waste heat boiler 2, a detoxification tank 3, a second waste heat boiler 4, and a heat exchange device 5. The conversion device 1 has a conversion device inlet and a conversion device outlet. The conversion device inlet is connected to the crude gas source. The conversion device 1 is used to perform a first conversion reaction on a portion of the crude gas to obtain first converted gas. The first waste heat boiler 2 has a first waste heat boiler inlet and a first waste heat boiler outlet. The first waste heat boiler inlet is connected to the crude gas source. The first waste heat boiler 2 is used to perform a first condensation on the remaining portion of the crude gas to obtain condensed crude gas. The detoxification tank 3 has a detoxification tank inlet and a detoxification tank outlet. The detoxification tank inlet is connected to the outlet of the first waste heat boiler. The detoxification tank 3 is used to perform a second conversion reaction on the condensed crude gas to obtain detoxified crude gas. The first shifted gas and the detoxified shifted gas are used to obtain detoxified gas; the second waste heat boiler 4 has a second waste heat boiler inlet and a second waste heat boiler outlet, the second waste heat boiler inlet is connected to the detoxification tank outlet, the second waste heat boiler 4 is used to perform a second condensation on the detoxified gas to obtain condensed gas; the heat exchange device 5 has a heat exchange device inlet and a heat exchange device outlet, the heat exchange device inlet is connected to the second waste heat boiler outlet, the heat exchange device 5 is used to exchange heat on the condensed gas to obtain the first shifted gas and the second shifted gas; the first shifted gas, the first shifted gas and the second shifted gas are introduced into the synthesis gas unit to prepare synthesis gas; wherein, along the direction from the detoxification tank inlet to the detoxification tank outlet, the detoxification tank 3 includes a first region and a second region connected in sequence, the first region is filled with hydrolysate, and the second region is filled with shift catalyst.

[0028] This application, by filling the detoxification tank 3 with a shift catalyst, allows the unshifted gas (i.e., condensed crude gas) to undergo a partial shift reaction. This reduces the gas distribution ratio of the shift converter 1, thereby lowering the pressure drop of the shift converter 1 and further increasing the load of the crude gas shift system, achieving a load exceeding 100%, or even as high as 110%. Specifically, a portion of the crude gas undergoes a first shift reaction in the shift converter 1 to obtain shifted gas; the remaining portion undergoes first condensation in the first waste heat boiler 2. This not only regulates the temperature of the crude gas to meet the temperature requirements of the subsequent second shift reaction and prevents the shift catalyst in the detoxification tank 3 from deactivating due to excessive temperature, but also removes impurities from the crude gas. By filling the detoxification tank 3 with a hydrolysate and a shift catalyst in the above manner, the composition of the condensed crude gas can be pre-adjusted under the action of the hydrolysate, optimizing the conditions for the second shift reaction. This facilitates the second shift reaction of CO and H2O in the condensed crude gas under the action of the shift catalyst and improves the reaction efficiency of the second shift reaction, thereby reducing the gas distribution ratio of the shift converter 1 and lowering the pressure drop of the shift converter 1. Simultaneously, the hydrolysant can remove carbonyl sulfur and other organic sulfur from the condensed crude coal gas. The detoxified gas undergoes a second condensation in the second waste heat boiler 4, which not only separates the water vapor produced by the second shift reaction, thus reducing the moisture content in the gas, but also regulates the gas temperature. The condensed gas undergoes heat exchange in the heat exchanger 5, which further reduces the gas temperature to meet the requirements of subsequent synthesis processes. Passing the aforementioned first shift gas, unshifted gas, and second shift gas into the synthesis gas unit can produce high-quality synthesis gas, thereby obtaining high-quality chemical products.

[0029] In one embodiment of this application, the inlet temperature of the detoxification tank 3 is 200-230°C; and / or, when the load of the conversion device 1 is greater than 80%, the detoxification tank 3 includes one or multiple detoxification tanks 3 arranged in parallel, preferably two detoxification tanks 3 arranged in parallel, and each detoxification tank 3 can be switched.

[0030] Preferably controlling the inlet temperature of the detoxification tank 3 within the aforementioned range helps the condensed crude gas to fully undergo the second shift reaction under the action of the shift catalyst, thereby further improving the reaction efficiency of the second shift reaction. Simultaneously, when the load of the shift converter 1 is greater than 80%, setting a second detoxification tank 32 in parallel with the first detoxification tank 31 in the detoxification tank 3 can meet the high-load operation of the crude gas shift system. However, when the load of the shift converter 1 decreases, simultaneous operation of both detoxification tanks may pose a risk of overheating. Therefore, a single detoxification tank (e.g., the first detoxification tank 31) can operate, while the other detoxification tank (e.g., the second detoxification tank 32) is in a hot standby state.

[0031] In one embodiment of this application, the crude gas conversion system further includes a new waste heat boiler 6, which is connected in parallel with a second waste heat boiler 4; and / or, the inner diameter of the inlet pipeline of the second waste heat boiler 4 is 105-115 cm, and the inner diameter of the outlet pipeline of the second waste heat boiler 4 is 95-105 cm; and / or, the temperature of the second waste heat boiler 4 is 240-260°C, and / or, the pressure of the second waste heat boiler 4 is 3.6-4.5 MPa; and / or, the inner diameter of the inlet pipeline of the new waste heat boiler 6 is 100-110 cm, and the inner diameter of the outlet pipeline of the new waste heat boiler 6 is 90-100 cm.

[0032] Since the condensed crude gas undergoes a second shift reaction under the action of the shift catalyst, the gas temperature will increase, thereby increasing the heat load of the second waste heat boiler 4. By setting up a new waste heat boiler 6 in parallel with the second waste heat boiler 4, and controlling the inner diameter of the inlet pipeline and the inner diameter of the outlet pipeline of the second waste heat boiler 4 and the new waste heat boiler 6, as well as the temperature of the second waste heat boiler 4, within the above range, the heat load of the second waste heat boiler 4 and the new waste heat boiler 6 can be balanced, thereby reducing the safety risks of equipment operation.

[0033] In one embodiment of this application, the inner diameter of the inlet pipe of the first waste heat boiler 2 is 120-135 cm, the inner diameter of the outlet pipe of the first waste heat boiler 2 is 110-122 cm; and / or, the temperature of the first waste heat boiler 2 is 200-220°C, and / or, the pressure of the first waste heat boiler 2 is 4-4.4 MPa.

[0034] Preferentially controlling the inner diameter of the inlet pipe, the inner diameter of the outlet pipe, the temperature, and the pressure of the first waste heat boiler 2 within the above-mentioned range helps to regulate the temperature, pressure, and flow rate of the crude gas, thereby facilitating the subsequent second conversion reaction.

[0035] In one embodiment of this application, the temperature of the conversion device 1 is 200–460°C, and / or the pressure of the conversion device 1 is 3.6–4.4 MPa; and / or the water-to-gas ratio of the first conversion gas is 0.3–0.65:1.

[0036] Preferred control of the temperature and pressure of the conversion device 1 within the above-mentioned range helps the crude gas to fully undergo the first conversion reaction, thereby helping to improve the CO conversion rate and H2 production, and obtaining first conversion gas with a water-to-gas ratio within the above-mentioned range.

[0037] In one embodiment of this application, the inlet temperature of the heat exchanger 5 is 240-260°C, and / or the outlet temperature of the heat exchanger 5 is 30-60°C; and / or the water-to-gas ratio of the unconverted gas is 0.4-0.8:1; and / or the water-to-gas ratio of the second converted gas is 0.35-0.7:1.

[0038] Preferably controlling the inlet and outlet temperatures of heat exchanger 5 within the aforementioned range helps control the temperature and water-to-gas ratio of the unconverted gas and the second converted gas, thereby facilitating the use of the unconverted gas and the second converted gas in subsequent syngas processes.

[0039] In another typical embodiment of this application, a process for producing syngas using the above-mentioned crude gas shift system is provided. The process includes: the crude gas is composed of a portion of crude gas and a remaining portion of crude gas; the portion of crude gas undergoes a first shift reaction to obtain a first shift gas; the remaining portion of crude gas undergoes a first condensation to obtain condensed crude gas; under the action of a shift catalyst and a hydrolysate, the condensed crude gas undergoes a second shift reaction to obtain detoxified unshifted gas and detoxified shift gas; the detoxified unshifted gas and detoxified shift gas undergo a second condensation to obtain condensed gas; the condensed gas undergoes heat exchange to obtain unshifted gas and second shift gas; and the first shift gas, unshifted gas, and second shift gas are used as raw materials for syngas.

[0040] This invention provides a process for producing syngas using the aforementioned crude gas shift system. The crude gas is divided into a partial crude gas and a remaining crude gas. The partial crude gas undergoes a first shift reaction, which reduces the CO content and increases the H2 content in the first shift gas. The remaining crude gas undergoes a first condensation, which not only regulates the temperature of the crude gas to meet the temperature requirements of the subsequent second shift reaction but also removes impurities. The condensed crude gas, under the action of a hydrolyzing agent, removes carbonyl sulfur and other organic sulfur compounds. Subsequently, CO and H2O in the condensed crude gas undergo a second shift reaction under the action of a shift catalyst, thereby improving the reaction efficiency of the second shift reaction and reducing the CO content in both the unconverted and detoxified shifted gas. The detoxified gas undergoes a second condensation, which not only separates the water vapor produced in the second shift reaction, reducing the moisture content in the gas, but also regulates the gas temperature. Heat exchange of the condensed gas further reduces its temperature, making it suitable as a feedstock for syngas.

[0041] In one embodiment of this application, the volume ratio of a portion of the crude gas to the remaining portion of the crude gas is 3-4:2-3, and / or the water-to-gas ratio of the crude gas is 0.6-0.85:1, and / or the volume ratio of the first shift gas, the detoxified but not shifted gas, and the detoxified shift gas is 4-6:2-3:2-3.

[0042] Preferably controlling the volume ratio of the partial crude gas to the remaining crude gas and the water-gas ratio of the crude gas within the above-mentioned range helps the partial crude gas and the remaining crude gas to undergo conversion reactions separately, thereby reducing the CO and H2O content in the syngas. Preferably controlling the volume ratio of the first conversion gas, the detoxified unconverted gas, and the detoxified conversion gas within the above-mentioned range helps to regulate the gas distribution ratio of the partial crude gas to the remaining crude gas, thereby helping to reduce the pressure drop on the first conversion gas side, and further helping to enable the crude gas conversion system to operate at a load higher than 100%, and even enabling the crude gas conversion system to reach a load of 110%.

[0043] In one embodiment of this application, relative to 50000~100000m 3 The volume of the shift catalyst in the condensed crude gas is 10–20 m³. 3 The volume of the hydrolysate is 10–18 m³. 3 The volume ratio of hydrolysant to shift catalyst is 1 to 1.3:1; and / or the shift catalyst is selected from any one or more of iron-chromium shift catalysts, copper-zinc shift catalysts, and cobalt-molybdenum shift catalysts; and / or the active component of the hydrolysant is an alkali metal.

[0044] Preferably, the type, volume, and volume ratio of the shift catalyst and hydrolysant are within the above-mentioned ranges. This facilitates the reaction of carbonyl sulfur and water with the hydrolysant at a lower temperature, thereby purifying the crude coal gas; it also facilitates the reaction of carbon monoxide and water with the shift catalyst, thereby adjusting the hydrogen-to-carbon ratio; and it helps the hydrolysant and shift catalyst to better exert their catalytic effects, thereby increasing the overall system load.

[0045] In one embodiment of this application, the temperature of the first conversion reaction is 250–450°C; and / or, the space velocity of the first conversion reaction is 4500–6500 h⁻¹. -1 ; and / or, the temperature of the second shift reaction is 230–460 °C; and / or, the space velocity of the second shift reaction is 2000–3000 h⁻¹. -1 .

[0046] Preferably controlling the temperature and space velocity of the first shift reaction within the above-mentioned range helps to increase the reaction rate of the first shift reaction of some of the crude gas, thereby helping to increase the CO conversion rate and H2 content; preferably controlling the temperature and space velocity of the second shift reaction within the above-mentioned range helps to ensure sufficient contact between the condensed crude gas and the shift catalyst, thereby improving the reaction efficiency of the second shift reaction.

[0047] The beneficial effects of this application will be further illustrated below with reference to the embodiments.

[0048] Example 1

[0049] Adopting such Figure 1The crude gas conversion system shown converts crude gas into syngas. Specifically, crude gas with a water-to-gas ratio of 0.6 is converted from 60m³ of crude gas into syngas. 3 Part of the crude coal gas and 50m 3 The remaining crude gas consists of...; a portion of the crude gas is fed into shift converter 1 through the inlet of the shift converter to undergo the first shift reaction, yielding 40m... 3 The first conversion gas has a temperature of 200°C, a pressure of 3.6 MPa, and a water-to-gas ratio of 0.3:1.

[0050] The remaining crude coal gas is introduced into the first waste heat boiler 2 through the inlet of the first waste heat boiler for the first condensation, resulting in 45m³ of gas. 3 The condensed crude gas is produced by condensing the crude gas. The inner diameter of the inlet pipeline of the first waste heat boiler 2 is 120cm, the inner diameter of the outlet pipeline of the first waste heat boiler 2 is 110cm, the temperature of the first waste heat boiler 2 is 200℃, and the pressure of the first waste heat boiler 2 is 4MPa.

[0051] The condensed crude gas is output from the outlet of the first waste heat boiler and enters the first detoxification tank 31 and the second detoxification tank 32, which are arranged in parallel, through the detoxification tank inlets of the first detoxification tank 31 and the second detoxification tank 32, respectively. Along the direction from the detoxification tank inlets of the first detoxification tank 31 and the second detoxification tank 32 to the detoxification tank outlets, each of the first detoxification tank 31 and the second detoxification tank 32 includes a first region and a second region connected in sequence. Each first region is filled with 10m³ of gas. 3 Alkali metal series hydrolysants, each of the second zones is filled with 10m³ of hydrolysants. 3 Cobalt-molybdenum based shift catalyst. Under the action of the shift catalyst and hydrolysant, the condensed crude gas undergoes a second shift reaction to obtain a product containing 30m... 3 Detoxification without gas change and 20m 3 The detoxified gas in the detoxification shift gas system has an inlet temperature of 200℃ for detoxification tank 3, a second shift reaction temperature of 230℃, and a space velocity of 2000 h⁻¹. -1 .

[0052] After being discharged from the detoxification tank outlets of the first detoxification tank 31 and the second detoxification tank 32, the detoxified gas is fed into the second waste heat boiler 4 and the newly added waste heat boiler 6, which are connected in parallel, for a second condensation to obtain condensed gas. The inner diameter of the inlet pipe of the second waste heat boiler 4 is 105 cm, the inner diameter of the outlet pipe of the second waste heat boiler 4 is 95 cm, the temperature of the second waste heat boiler 4 is 340℃, and the pressure of the second waste heat boiler 4 is 3.6 MPa. The inner diameter of the inlet pipe of the newly added waste heat boiler 6 is 100 cm, and the inner diameter of the outlet pipe of the newly added waste heat boiler 6 is 90 cm.

[0053] After being discharged from the outlets of the second waste heat boiler and the newly added waste heat boiler 6, the condensate gas is introduced into heat exchanger 5 through the inlet of the heat exchanger for heat exchange, resulting in a 25m³ heat exchange solution. 3 Unchanged gas and 15m 3 The second shift gas has an inlet temperature of 240°C and an outlet temperature of 30°C. The water-to-gas ratio of the unshifted gas is 0.4:1, and the water-to-gas ratio of the second shift gas is 0.35:1.

[0054] The first converted gas is output from the outlet of the conversion device, and the unconverted gas and the second converted gas are output from the outlet of the heat exchanger. The first converted gas, the unconverted gas and the second converted gas are then fed into the synthesis gas unit to produce synthesis gas.

[0055] Example 2

[0056] Adopting such Figure 1 The crude gas conversion system shown converts crude gas into syngas. Specifically, crude gas with a water-to-gas ratio of 0.6 is converted from 70m³ of gas into syngas. 3 Part of the crude coal gas and 50m 3 The remaining crude gas is composed of...; a portion of the crude gas is fed into shift converter 1 through the inlet of the shift converter to undergo the first shift reaction, yielding 45m... 3 The first shift gas, wherein the temperature of shift device 1 is 350℃, the pressure of shift device 1 is 4MPa, and the space velocity of the first shift reaction is 5500 h⁻¹. -1 The water-to-gas ratio of the first transformed gas is 0.5:1.

[0057] The remaining crude coal gas is introduced into the first waste heat boiler 2 through the inlet of the first waste heat boiler for the first condensation, resulting in 45m³ of gas. 3 The condensed crude gas is produced by condensing the crude gas. The inner diameter of the inlet pipeline of the first waste heat boiler 2 is 128 cm, the inner diameter of the outlet pipeline of the first waste heat boiler 2 is 116 cm, the temperature of the first waste heat boiler 2 is 210℃, and the pressure of the first waste heat boiler 2 is 4.2 MPa.

[0058] The condensed crude gas is output from the outlet of the first waste heat boiler and enters the first detoxification tank 31 and the second detoxification tank 32, which are arranged in parallel, through the detoxification tank inlets of the first detoxification tank 31 and the second detoxification tank 32, respectively. Along the direction from the detoxification tank inlets of the first detoxification tank 31 and the second detoxification tank 32 to the detoxification tank outlets, each of the first detoxification tank 31 and the second detoxification tank 32 includes a first region and a second region connected in sequence. Each first region is filled with 10m³ of gas. 3 Alkali metal series hydrolysants, each of the second zones is filled with 10m³ of hydrolysants. 3 Cobalt-molybdenum based shift catalyst. Under the action of the shift catalyst and hydrolysant, the condensed crude gas undergoes a second shift reaction to obtain a product containing 35m... 3Detoxification without gas change and 25m 3 The detoxified gas in the detoxification shift gas system has an inlet temperature of 215℃ for detoxification tank 3, a second shift reaction temperature of 355℃, and a space velocity of 2500 h⁻¹. -1 .

[0059] After the detoxified gas is output from the detoxification tank outlets of the first detoxification tank 31 and the second detoxification tank 32, it is fed into the second waste heat boiler 4 and the newly added waste heat boiler 6, which are set in parallel, for a second condensation to obtain condensed gas. The inner diameter of the inlet pipe of the second waste heat boiler 4 is 110cm, the inner diameter of the outlet pipe of the second waste heat boiler 4 is 100cm, the temperature of the second waste heat boiler 4 is 250℃, and the pressure of the second waste heat boiler 4 is 4MPa. The inner diameter of the inlet pipe of the newly added waste heat boiler 6 is 105cm, and the inner diameter of the outlet pipe of the newly added waste heat boiler 6 is 95cm.

[0060] After being discharged from the outlets of the second waste heat boiler and the newly added waste heat boiler 6, the condensate gas is introduced into heat exchanger 5 through the inlet of the heat exchanger for heat exchange, resulting in 28m³ of condensate. 3 Unchanged gas and 18m 3 The second shift gas has an inlet temperature of 260°C and an outlet temperature of 45°C. The water-to-gas ratio of the unshifted gas is 0.6:1, and the water-to-gas ratio of the second shift gas is 0.55:1.

[0061] The first converted gas is output from the outlet of the conversion device, and the unconverted gas and the second converted gas are output from the outlet of the heat exchanger. The first converted gas, the unconverted gas and the second converted gas are then fed into the synthesis gas unit to produce synthesis gas.

[0062] Example 3

[0063] Adopting such Figure 1 The crude gas conversion system shown converts crude gas into syngas. Specifically, crude gas with a water-to-gas ratio of 0.6 is converted from 60m³ of crude gas into syngas. 3 Part of the crude coal gas and 50m 3 The remaining crude gas consists of...; a portion of the crude gas is fed into shift converter 1 through the inlet of the shift converter to undergo the first shift reaction, yielding 40m... 3 The first shift gas, wherein the temperature of shift device 1 is 460℃, the pressure of shift device 1 is 4.4MPa, and the space velocity of the first shift reaction is 6500h⁻¹. -1 The water-to-gas ratio of the first shift gas is 0.65:1.

[0064] The remaining crude coal gas is introduced into the first waste heat boiler 2 through the inlet of the first waste heat boiler for the first condensation, resulting in 45m³ of gas. 3The condensed crude gas is generated in the first waste heat boiler 2, where the inner diameter of the inlet pipeline of the first waste heat boiler 2 is 135cm, the inner diameter of the outlet pipeline of the first waste heat boiler 2 is 122cm, the temperature of the first waste heat boiler 2 is 220℃, and the pressure of the first waste heat boiler 2 is 4.4MPa.

[0065] The condensed crude gas is output from the outlet of the first waste heat boiler and enters the first detoxification tank 31 and the second detoxification tank 32, which are arranged in parallel, through the detoxification tank inlets of the first detoxification tank 31 and the second detoxification tank 32, respectively. Along the direction from the detoxification tank inlets of the first detoxification tank 31 and the second detoxification tank 32 to the detoxification tank outlets, each of the first detoxification tank 31 and the second detoxification tank 32 includes a first region and a second region connected in sequence. Each first region is filled with 10m³ of gas. 3 Alkali metal series hydrolysants, each of the second zones is filled with 10m³ of hydrolysants. 3 Cobalt-molybdenum based shift catalyst. Under the action of the shift catalyst and hydrolysant, the condensed crude gas undergoes a second shift reaction to obtain a product containing 30m... 3 Detoxification without gas change and 20m 3 The detoxified gas in the detoxification shift gas system has an inlet temperature of 230℃ for detoxification tank 3, a second shift reaction temperature of 460℃, and a space velocity of 3000 h⁻¹. -1 .

[0066] After being discharged from the detoxification tank outlets of the first detoxification tank 31 and the second detoxification tank 32, the detoxified gas is fed into the second waste heat boiler 4 and the newly added waste heat boiler 6, which are connected in parallel, for a second condensation to obtain condensed gas. The inner diameter of the inlet pipeline of the second waste heat boiler 4 is 115 cm, the inner diameter of the outlet pipeline of the second waste heat boiler 4 is 105 cm, the temperature of the second waste heat boiler 4 is 260℃, and the pressure of the second waste heat boiler 4 is 4.5 MPa. The inner diameter of the inlet pipeline of the newly added waste heat boiler 6 is 105 cm, and the inner diameter of the outlet pipeline of the newly added waste heat boiler 6 is 95 cm.

[0067] After being discharged from the outlets of the second waste heat boiler and the newly added waste heat boiler 6, the condensate gas is introduced into heat exchanger 5 through the inlet of the heat exchanger for heat exchange, resulting in a 25m³ heat exchange solution. 3 Unchanged gas and 15m 3 The second shift gas has an inlet temperature of 260°C and an outlet temperature of 60°C. The water-to-gas ratio of the unshifted gas is 0.8:1, and the water-to-gas ratio of the second shift gas is 0.7:1.

[0068] The first converted gas is output from the outlet of the conversion device, and the unconverted gas and the second converted gas are output from the outlet of the heat exchanger. The first converted gas, the unconverted gas and the second converted gas are then fed into the synthesis gas unit to produce synthesis gas.

[0069] Example 4

[0070] The difference from Example 1 is that the volume ratio of a portion of the crude gas to the remaining portion of the crude gas is 4:3, and syngas is finally prepared.

[0071] Example 5

[0072] The difference from Example 1 is that the volume ratio of a portion of the crude gas to the remaining portion of the crude gas is 3:4, and syngas is finally prepared.

[0073] Example 6

[0074] The difference from Example 1 is that the volume ratio of the first shift gas, the detoxified unshifted gas, and the detoxified shift gas is 6:2:3, and the final synthesis gas is prepared.

[0075] Example 7

[0076] The difference from Example 1 is that the volume ratio of the first shift gas, the detoxified unshifted gas, and the detoxified shift gas is 1:1:1, and the final synthesis gas is prepared.

[0077] Example 8

[0078] The difference from Example 1 is that the volume ratio of hydrolysate to shift catalyst is 1.3:1, and syngas is finally prepared.

[0079] Example 9

[0080] The difference from Example 1 is that the volume ratio of hydrolysate to shift catalyst is 1:2, and syngas is finally prepared.

[0081] Comparative Example 1

[0082] The difference from Example 1 is that the detoxification tank 3 is not filled with a shift catalyst.

[0083] Test methods

[0084] The calculation method for the load of the crude gas conversion system is: actual crude gas volume / design crude gas volume. The actual crude gas volume is measured by the flow meter at the inlet of the conversion unit.

[0085] Table 1

[0086] Examples / Comparative Examples load(%) Example 1 108 Example 2 110 Example 3 108 Example 4 105 Example 5 100 Example 6 103 Example 7 102 Example 8 103 Example 9 101 Comparative Example 1 95

[0087] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:

[0088] This application, by filling the detoxification tank with a shift catalyst, allows the unshifted gas (i.e., condensed crude gas) to undergo a partial shift reaction. This reduces the gas distribution ratio in the shift converter, thereby lowering the pressure drop and further increasing the load on the crude gas shift system, achieving a load exceeding 100%, or even as high as 110%. Specifically, a portion of the crude gas undergoes a first shift reaction in the shift converter to obtain shifted gas; the remaining portion undergoes first condensation in a first waste heat boiler. This not only regulates the temperature of the crude gas to meet the temperature requirements of the subsequent second shift reaction, preventing the shift catalyst in the detoxification tank from deactivating due to excessive temperature, but also removes impurities from the crude gas. By filling the detoxification tank with a hydrolysate and a shift catalyst in the above manner, the composition of the condensed crude gas can be pre-adjusted under the action of the hydrolysate, optimizing the conditions for the second shift reaction. This facilitates the second shift reaction of CO and H2O in the condensed crude gas under the action of the shift catalyst, improving the reaction efficiency and thus reducing the gas distribution ratio and pressure drop in the shift converter. Simultaneously, the hydrolysant can remove carbonyl sulfur and other organic sulfur from the condensed crude coal gas. The detoxified gas undergoes a second condensation in the second waste heat boiler, which not only separates the water vapor produced by the second shift reaction, thus reducing the moisture content in the gas, but also regulates the gas temperature. Further heat exchange in the condensed gas equipment further reduces the gas temperature to meet the requirements of subsequent synthesis processes. Passing the aforementioned first shift gas, unshifted gas, and second shift gas into the syngas unit can produce high-quality syngas, thereby obtaining high-quality chemical products.

[0089] The above are merely embodiments of the present invention and are not intended to limit the invention. Those skilled in the art will recognize that the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A crude gas conversion system, characterized in that, The crude gas conversion system includes: The conversion device (1) has a conversion device inlet and a conversion device outlet. The conversion device inlet is connected to a crude gas source. The conversion device (1) is used to perform a first conversion reaction on a portion of the crude gas to obtain a first converted gas. The first waste heat boiler (2) has a first waste heat boiler inlet and a first waste heat boiler outlet. The first waste heat boiler inlet is connected to the crude coal gas source. The first waste heat boiler (2) is used to perform first condensation on the remaining part of the crude coal gas to obtain condensed crude coal gas. The detoxification tank (3) has a detoxification tank inlet and a detoxification tank outlet. The detoxification tank inlet is connected to the outlet of the first waste heat boiler. The detoxification tank (3) is used to perform a second conversion reaction on the condensed crude coal gas to obtain detoxified gas including detoxified unconverted gas and detoxified converted gas. The second waste heat boiler (4) has a second waste heat boiler inlet and a second waste heat boiler outlet. The second waste heat boiler inlet is connected to the detoxification tank outlet. The second waste heat boiler (4) is used to perform a second condensation on the detoxification gas to obtain condensed gas. The heat exchange device (5) has a heat exchange device inlet and a heat exchange device outlet. The heat exchange device inlet is connected to the outlet of the second waste heat boiler. The heat exchange device (5) is used to exchange heat with the condensate to obtain unchanged gas and second changed gas. The first shift gas, the unshifted gas, and the second shift gas are fed into the synthesis gas unit to prepare synthesis gas; Along the direction from the inlet to the outlet of the detoxification tank, the detoxification tank (3) includes a first region and a second region connected in sequence. The first region is filled with a hydrolysate and the second region is filled with a conversion catalyst. The crude gas conversion system also includes a new waste heat boiler (6), which is connected in parallel with the second waste heat boiler (4); the inner diameter of the inlet pipeline of the second waste heat boiler (4) is 105~115cm, and the inner diameter of the outlet pipeline of the second waste heat boiler (4) is 95~105cm; the temperature of the second waste heat boiler (4) is 240~260℃; the pressure of the second waste heat boiler (4) is 3.6~4.5MPa; the inner diameter of the inlet pipeline of the new waste heat boiler (6) is 100~110cm, and the inner diameter of the outlet pipeline of the new waste heat boiler (6) is 90~100cm.

2. The crude gas conversion system according to claim 1, characterized in that, The inlet temperature of the detoxification tank (3) is 200~230℃; and / or, when the load of the conversion device (1) is greater than 80%, the detoxification tank (3) includes one or multiple detoxification tanks (3) arranged in parallel.

3. The crude gas conversion system according to claim 2, characterized in that, The detoxification tank (3) includes two detoxification tanks (3) arranged in parallel, and each detoxification tank (3) can be switched.

4. The crude gas conversion system according to claim 1, characterized in that, The inner diameter of the inlet pipe of the first waste heat boiler (2) is 120~135cm, and the inner diameter of the outlet pipe of the first waste heat boiler (2) is 110~122cm; and / or, the temperature of the first waste heat boiler (2) is 200~220℃, and / or, the pressure of the first waste heat boiler (2) is 4~4.4MPa.

5. The crude gas conversion system according to any one of claims 1 to 3, characterized in that, The temperature of the conversion device (1) is 200~460℃, and / or the pressure of the conversion device (1) is 3.6~4.4MPa; and / or the water-to-gas ratio of the first conversion gas is 0.3~0.65:

1.

6. The crude gas conversion system according to any one of claims 1 to 3, characterized in that, The inlet temperature of the heat exchanger (5) is 240~260℃, and / or the outlet temperature of the heat exchanger (5) is 30~60℃; and / or the water-to-gas ratio of the unconverted gas is 0.4~0.8:1; and / or the water-to-gas ratio of the second converted gas is 0.35~0.7:

1.

7. A process for producing syngas using the crude gas shift system according to any one of claims 1 to 6, characterized in that, The process includes: The crude coal gas consists of a portion of crude coal gas and a remaining portion of crude coal gas. The crude coal gas is subjected to a first conversion reaction to obtain first conversion gas; The remaining portion of crude coal gas is subjected to a first condensation to obtain condensed crude coal gas. Under the action of a shift catalyst and a hydrolysant, the condensed crude coal gas undergoes a second shift reaction to obtain detoxified gas, which includes detoxified unshifted gas and detoxified shifted gas. The detoxified gas is subjected to a second condensation to obtain condensed gas; The condensate undergoes heat exchange to obtain unchanged gas and second changed gas. The first shifted gas, the unshifted gas, and the second shifted gas are used as raw materials for synthesis gas.

8. The process according to claim 7, characterized in that, The volume ratio of the partial crude gas to the remaining crude gas is 3~4:2~3, and / or the water-to-gas ratio of the crude gas is 0.6~0.85:1, and / or the volume ratio of the first shift gas, the detoxified but not shifted gas, and the detoxified shift gas is 4~6:2~3:2~3.

9. The process according to claim 7, characterized in that, Relative to 50,000~100,000m 3 The condensed crude gas, wherein the volume of the shift catalyst is 10-20 m³. 3 The volume of the hydrolysate is 10~18m³. 3 The volume ratio of the hydrolysant to the shift catalyst is 1~1.3:1; and / or the shift catalyst is selected from any one or more of iron-chromium shift catalysts, copper-zinc shift catalysts, and cobalt-molybdenum shift catalysts; and / or the active component of the hydrolysant is an alkali metal.

10. The process according to any one of claims 7 to 9, characterized in that, The temperature of the first conversion reaction is 250~450℃; and / or, the space velocity of the first conversion reaction is 4500~6500 h⁻¹. -1 ; and / or, the temperature of the second shift reaction is 230~460℃; and / or, the space velocity of the second shift reaction is 2000~3000 h⁻¹. -1 .

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