Efficient water gas preparation process and system

Abstract

The invention provides an efficient water gas preparation process and system, and belongs to the technical field of water gas preparation processes. The efficient water gas preparation process comprises the following steps: S1, putting raw materials into a furnace, starting a system, and igniting for combustion; s2, burning and releasing heat: heating and evaporating the raw materials in the furnace to form steam; s3, the raw material steam enters a water gas preparation chamber from the furnace and is subjected to combustion, blowing and purification, and water gas is obtained; s4, the water gas enters a gas collection device for water gas collection. According to the method, the preparation volume of the water gas can be increased and the waste of resources can be reduced by increasing the blowing circulation purification step.

Description

Technical Field

[0001] The present application relates to the field of water gas preparation technology, and specifically, to a water gas efficient preparation technology and system. Background Art

[0002] Water gas is a gas generated by water vapor passing through hot coke. Its main components are carbon monoxide and hydrogen. After combustion, it emits water and carbon dioxide, and contains trace amounts of CO, hydrocarbons and NOx. The combustion rate is 7.5 times that of gasoline, and it has good anti-explosion properties. According to foreign research and patent reports, the compression ratio can reach 12.5, the thermal efficiency is increased by 20-40%, the power is increased by 15%, the fuel consumption is reduced by 30%, and the tail gas purification is close to the European IV standard. It can also be purified with a trace amount of platinum catalyst. Compared with alcohol and ether, it simplifies manufacturing and reduces equipment, and has lower costs and investments. Compression or liquefaction is similar to hydrogen, but there is no need to remove CO, and the investment in station construction is lower. The reduced cost and investment can also partially compensate for the investment and cost of compression (compression is also required for the production of alcohol ether) or liquefaction. It is toxic and is used as a fuel in industry and as a chemical raw material.

[0003] Passing water vapor through a hot coal seam can produce cleaner water gas (mainly CO and H2), with the phenomenon that the flame rises higher and turns light blue (the color of hydrogen and CO burning). The chemical equation is. This is why wet coal burns more vigorously than dry coal. Gas plants often deliberately add a small amount of unpleasant-smelling gas to domestic water gas, so that when the gas leaks, it can be smelled and discovered in time. Methane and water can also produce water gas with a chemical equation of CH4+H2O=CO+3H2, another low calorific value gas. It is obtained by the reaction of steam with burning anthracite or coke. The main components are hydrogen and carbon monoxide, and also contain a small amount of carbon dioxide, nitrogen and methane; the content of each component depends on the raw materials used and the gasification conditions. It is mainly used as a raw material for synthetic ammonia and synthetic liquid fuels, or as a supplementary source of industrial fuel gas. Water gas production generally adopts intermittent periodic fixed bed production technology. The furnace structure adopts the UGI gasification furnace type. The above reactions are all endothermic reactions, so heat must be supplied to the gasifier. Generally, air is first sent into the furnace to burn part of the fuel, store the heat in the fuel layer and the heat storage chamber, and then steam is introduced into the hot fuel layer for reaction. Since the reaction is endothermic, when the temperature of the fuel layer and the heat storage chamber drops to a certain temperature, air is sent into the furnace again to heat it up, and the cycle continues. When the task is to produce fuel gas, in order to increase the calorific value of the gas, the temperature of the gas discharged from the furnace is sometimes increased, so that oil can be sprayed into the hot gas to crack the oil, thus obtaining the so-called heated gas.

[0004] The CO+H2 content of the obtained raw gas is 55%-60%. Since fixed bed coal gasification generally has a low steam decomposition rate (≤45%), the steam consumption is large; at the same time, a large amount of CO2 is released during the purification process of the synthetic ammonia raw gas, which is not used, resulting in energy waste. Summary of the invention

[0005] In order to make up for the above shortcomings, the present application provides a water gas efficient preparation process and system, which aims to improve the problem that a large amount of CO2 is discharged and not utilized during the purification process of synthetic ammonia raw gas, resulting in energy waste.

[0006] On the one hand, the embodiment of the present application provides an efficient water gas preparation process, comprising the following steps: S1: raw materials are put into a furnace, the system is turned on, and ignition is performed;

[0007] S2: Combustion releases heat, and the raw materials in the furnace evaporate and turn into steam;

[0008] S3: The raw material steam enters the water gas preparation chamber from the furnace, undergoes combustion and air blowing purification, and obtains water gas;

[0009] S4: The water gas enters the gas collecting device for water gas collection. The addition of the air blowing cycle purification step can increase the preparation volume of the water gas and reduce the waste of resources.

[0010] In a specific implementation, in S3, the following steps are also included:

[0011] S31: Blowing stage, air is blown in from the bottom of the furnace, the material layer is heated up, and the exhaust gas is discharged from the top of the furnace;

[0012] S32: Steam blowing stage, steam is blown into the water gas preparation chamber from the bottom to discharge the residual waste gas in S31 to ensure the quality of the gas produced;

[0013] S33: In the primary upward blowing gasification stage, water vapor is blown in from the bottom of the water-gas preparation chamber, absorbing heat and gasifying in the material layer to produce gas, which escapes and is recovered from the top. At this time, the temperature of the lower part of the material layer drops significantly;

[0014] S34: Bottom-blowing gasification stage: water vapor is blown into the water gas preparation chamber from the top, and a water vapor gasification reaction occurs in the water gas preparation chamber. At this time, the heat of the material layer is further absorbed, and the produced water gas escapes and is recovered from the bottom of the water gas preparation chamber, and the temperature of the upper material layer also drops significantly;

[0015] S35: Secondary upward blowing gas production stage: This is a stage set for safe operation. Its purpose is to use water vapor to drive out the water gas accumulated at the bottom of the water gas preparation chamber during the upper gas production to prevent accidents caused by the encounter with the blast air. However, at this time, the gas escaping from the top of the water gas preparation chamber still contains CO+H2, so the escaping gas must be recovered;

[0016] S36: Air blowing stage: Air is blown in from the bottom of the furnace to release the remaining gas in the water-gas preparation chamber and out from the top of the water-gas preparation chamber, and the gas is recovered. This cycle takes between 2.5 and 4.5 minutes.

[0017] In a specific embodiment, the raw material is burned to 350-550°C, enters the convection section of the tube fixed bed reactor of the integrated converter at a mass space velocity of 0.1-5 hours-1, and is heated to 550-620°C by a heater. In step 3, a catalyst can be added to the water gas preparation chamber, the temperature is constant at 550-620°C, and the bed pressure is 0.1-0.5Mpa. When the catalyst bed enters the water gas reaction process, 550-620°C high-temperature steam is introduced at a gas velocity of less than 100 meters / second for 5-180 minutes, and a water gas reaction occurs with the catalyst carbon deposition until CO in the tail gas is less than 0.1v / v%. In step S2 and step S3, a waste heat recovery device is provided.

[0018] On the other hand, an embodiment of the present application further provides a water-gas efficient preparation system, including a central processing unit, an ignition device, a fuel control valve, a liquid replenishment unit, and a liquid level unit.

[0019] The central processing unit is used to control the operation of the system accordingly; the ignition device is connected to the central processing unit and is used to control the ignition and start-up of the system; the fuel control valve, which is connected to the central processing unit, is used to adjust the supply of fuel; the liquid replenishing unit, which is connected to the central processing unit, is used to control the amount of raw material liquid added to the furnace.

[0020] In a specific embodiment, it also includes a liquid level unit and a temperature detection unit, wherein the liquid level unit is connected to the furnace through a liquid level pipeline, and the central processing unit is connected to the liquid level unit for real-time acquisition of the liquid level in the furnace, and multiple temperature detection units are arranged in the furnace and the water-gas preparation room, and the temperature detection unit is connected to the central processing unit for detecting the temperature in the furnace and the water-gas preparation room.

[0021] In a specific implementation manner, a steam flow unit and a water-gas flow unit are also included, wherein the steam flow unit and the water-gas flow unit are both connected to a central processor for obtaining the flow conditions of raw steam and water-gas in real time.

[0022] In a specific implementation scheme, the control method during system startup comprises the following steps:

[0023] A1. The central processor controls the fuel control valve to open and the ignition device to ignite;

[0024] A2, the central processing unit obtains the liquid level in the furnace through the liquid level unit, and determines whether the liquid level in the furnace reaches the preset liquid level value; if yes, proceed to step A4; if no, proceed to step A3;

[0025] A3, the central processing unit controls the replenishing unit to start, replenish the raw material liquid into the furnace, and returns to step A2;

[0026] A4. The central processor obtains the temperature in the furnace and the water gas preparation room in real time through the temperature detection unit;

[0027] A5, the central processing unit determines whether the temperature in the water gas preparation room meets the requirements of the preset temperature range; if yes, proceed to step A6; if no, return to step A4;

[0028] A6. The central processor obtains the raw material steam flow rate in real time through the steam flow unit;

[0029] A7, the central processing unit determines whether the raw material steam flow rate reaches the preset steam flow rate value; if yes, proceed to step A8; if no, return to step A6;

[0030] A8, the central processor obtains the water gas flow rate in real time through the water gas flow unit;

[0031] A9, the central processing unit determines whether the water gas flow rate reaches the preset flow rate value; if yes, proceed to step B10; if no, return to step A8;

[0032] A10, the CPU maintains the current system operation status.

[0033] Beneficial effects: The present application provides a water gas efficient preparation process and system, S1: raw materials are put into the furnace, the system is turned on, and ignition is carried out; S2: combustion releases heat, the raw materials in the furnace are heated and evaporated, and become steam; S3: the raw material steam enters the water gas preparation chamber from the furnace, and is combusted and blown for purification to obtain water gas; S4: the water gas enters the gas collection device for water gas collection. Among them, by adding the blowing cycle purification step, the preparation volume of water gas can be increased, and the waste of resources can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the implementation methods of the present application, the drawings required for use in the implementation methods will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 This is a block diagram of the efficient water gas preparation process and system structure provided in the implementation mode of the present application;

[0036] Figure 2 This is a structural block diagram of step 3 provided for the implementation method of this application. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0038] See also Figure 1 and Figure 2 The present application provides a water gas efficient preparation process, comprising the following steps: S1: raw materials are put into a furnace, the system is turned on, and ignition is performed; S2: combustion releases heat, the raw materials in the furnace are heated and evaporated, and become steam; S3: the raw material steam enters the water gas preparation chamber from the furnace, and is combusted and blown for purification to obtain water gas; S4: the water gas enters the gas collection device for water gas collection. Among them, by adding the blowing cycle purification step, the preparation volume of water gas can be increased, and the waste of resources can be reduced.

[0039] In this embodiment, in S3, the following steps are also included: S31: blowing stage, air is blown in from the bottom of the furnace, the material layer is heated up, and the exhaust gas is discharged from the top of the furnace; S32: steam blowing stage, steam is blown in from the bottom of the water-gas preparation chamber, and the residual exhaust gas in S31 is discharged to ensure the quality of the gas produced by gasification; S33: a primary upper blowing gasification stage, water vapor is blown in from the bottom of the water-gas preparation chamber, and heat is absorbed and gasified in the material layer to produce gas, which is recovered from the top, and the temperature of the lower part of the material layer drops significantly at this time; S34: lower blowing gasification stage: water vapor is blown in from the top of the water-gas preparation chamber, and a water vapor gasification reaction occurs in the water-gas preparation chamber. At this time, the heat of the material layer is blown in. One-step absorption, the produced water gas escapes from the bottom of the water gas preparation chamber and is recovered, and the temperature of the upper material layer also drops significantly; S35: secondary upward blowing gasification stage: this is a stage set for safe operation, its purpose is to use water vapor to drive out the water gas accumulated at the bottom of the water gas preparation chamber during the upper gasification, so as to prevent accidents caused by encountering the blast air, but at this time the gas escaping from the top of the water gas preparation chamber still contains CO+H2, so the escaping gas must be recovered; S36: air blowing stage: air is blown into the bottom of the furnace, the gas in the water gas preparation chamber and the remaining gas escapes from the top of the water gas preparation chamber, and is recovered. This cycle takes between 2.5 and 4.5 minutes.

[0040] In this embodiment, the raw material is burned to 350-550°C, enters the convection section of the tube fixed bed reactor of the integrated converter at a mass space velocity of 0.1-5 hours-1, and is heated to 550-620°C by the heater. In step 3, a catalyst can be added to the water gas preparation chamber, the temperature is constant at 550-620°C, and the bed pressure is 0.1-0.5Mpa. When the catalyst bed enters the water gas reaction process, 550-620°C high-temperature steam is introduced at a gas velocity of less than 100 meters / second for 5-180 minutes, and a water gas reaction occurs with the catalyst carbon deposition until CO in the tail gas is less than 0.1v / v%. In step S2 and step S3, a waste heat recovery device is provided.

[0041] See also Figure 1 and Figure 2The embodiment of the present application further provides a water-gas efficient preparation system, including a central processing unit, an ignition device, a fuel control valve, a liquid replenishment unit, and a liquid level unit.

[0042] The central processing unit is used to control the operation of the system accordingly; the ignition device is connected to the central processing unit to control the ignition and start of the system; the fuel control valve is connected to the central processing unit to adjust the supply of fuel; the liquid replenishment unit is connected to the central processing unit to control the amount of raw material liquid added to the furnace. It also includes a liquid level unit and a temperature detection unit, wherein the liquid level unit is connected to the furnace through a liquid level pipeline, and the central processing unit is connected to the liquid level unit to obtain the liquid level in the furnace in real time. There are multiple temperature detection units in the furnace and the water gas preparation room, and the temperature detection unit is connected to the central processing unit to detect the temperature in the furnace and the water gas preparation room. It also includes a steam flow unit and a water gas flow unit, wherein the steam flow unit and the water gas flow unit are both connected to the central processing unit to obtain the flow of raw steam and water gas in real time.

[0043] In this embodiment, the control method during the system startup process includes the following steps:

[0044] A1. The central processor controls the fuel control valve to open and the ignition device to ignite;

[0045] A2, the central processing unit obtains the liquid level in the furnace through the liquid level unit, and determines whether the liquid level in the furnace reaches the preset liquid level value; if yes, proceed to step A4; if no, proceed to step A3;

[0046] A3, the central processing unit controls the replenishing unit to start, replenish the raw material liquid into the furnace, and returns to step A2;

[0047] A4. The central processor obtains the temperature in the furnace and the water gas preparation room in real time through the temperature detection unit;

[0048] A5, the central processing unit determines whether the temperature in the water gas preparation room meets the requirements of the preset temperature range; if yes, proceed to step A6; if no, return to step A4;

[0049] A6. The central processor obtains the raw material steam flow rate in real time through the steam flow unit;

[0050] A7, the central processing unit determines whether the raw material steam flow rate reaches the preset steam flow rate value; if yes, proceed to step A8; if no, return to step A6;

[0051] A8, the central processor obtains the water gas flow rate in real time through the water gas flow unit;

[0052] A9, the central processing unit determines whether the water gas flow rate reaches the preset flow rate value; if yes, proceed to step B10; if no, return to step A8;

[0053] A10, the CPU maintains the current system operation status.

[0054] The working principle of the water gas efficient preparation process and system:

[0055] S1: the raw materials are put into the furnace, the system is turned on, and the ignition is started; S2: the combustion releases heat, the raw materials in the furnace are heated and evaporated, and become steam; S3: the raw material steam enters the water gas preparation chamber from the furnace, and is burned and blown for purification to obtain water gas; S4: the water gas enters the gas collection device for water gas collection. Among them, by adding the blowing cycle purification step, the preparation volume of water gas can be increased, and the waste of resources can be reduced.

[0056] The above description is only an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

Claims

1. A highly efficient water gas preparation process, characterized in that: The following steps are involved: S1: Raw materials are put into the furnace, the system is turned on, and ignition and combustion are started; S2: Combustion releases heat, and the raw materials in the furnace evaporate and turn into steam; S3: The raw material steam enters the water gas preparation chamber from the furnace, undergoes combustion and air blowing purification, and obtains water gas; S4: The water gas enters the gas collecting device for water gas collection.

2. The process for efficiently preparing water gas according to claim 1, characterized in that: In S3, the following steps are also included: S31: Blowing stage, air is blown in from the bottom of the furnace, the material layer is heated up, and the exhaust gas is discharged from the top of the furnace; S32: Steam blowing stage, steam is blown into the water gas preparation chamber from the bottom to discharge the residual waste gas in S31 to ensure the quality of the gas produced; S33: In the primary upward blowing gasification stage, water vapor is blown in from the bottom of the water-gas preparation chamber, absorbing heat and gasifying in the material layer to produce gas, which escapes and is recovered from the top. At this time, the temperature of the lower part of the material layer drops significantly; S34: Bottom-blowing gasification stage: water vapor is blown into the water gas preparation chamber from the top, and a water vapor gasification reaction occurs in the water gas preparation chamber. At this time, the heat of the material layer is further absorbed, and the produced water gas escapes and is recovered from the bottom of the water gas preparation chamber, and the temperature of the upper material layer also drops significantly; S35: Secondary upward blowing gas production stage: This is a stage set for safe operation. Its purpose is to use water vapor to drive out the water gas accumulated at the bottom of the water gas preparation chamber during the upper gas production to prevent accidents caused by the encounter with the blast air. However, at this time, the gas escaping from the top of the water gas preparation chamber still contains CO+H2, so the escaping gas must be recovered; S36: Air blowing stage: Air is blown in from the bottom of the furnace to release the remaining gas in the water-gas preparation chamber and out from the top of the water-gas preparation chamber, and the gas is recovered. This cycle takes between 2.5 and 4.5 minutes.

3. The efficient water gas preparation process according to claim 1, characterized in that: In S, the raw materials are burned to 350-550°C, enter the convection section of the tube fixed bed reactor of the integrated converter at a mass space velocity of 0.1-5h-1, and are heated to 550-620°C by the heater.

4. The process for efficiently preparing water gas according to claim 1, characterized in that: In step 3, a catalyst may be added to the water gas preparation chamber, the temperature may be kept constant at 550-620° C., and the bed pressure may be 0.1-0.5 MPa.

5. A water gas efficient preparation process according to claim 4, characterized in that: When the catalyst bed enters the water-gas reaction process, high-temperature water vapor at 550-620°C is introduced at a gas velocity lower than 100 m / s for 5-180 minutes to react with the carbon deposits on the catalyst until the CO in the tail gas is less than 0.1 v / v%.

6. The process for efficiently preparing water gas according to claim 1, characterized in that: In step S2 and step S3, a waste heat recovery device is provided.

7. A water gas efficient preparation system, characterized in that: It includes a central processing unit, an ignition device, a fuel control valve, a liquid replenishing unit, and a liquid level unit, wherein the central processing unit is used to control the operation of the system accordingly; the ignition device is connected to the central processing unit and is used to control the ignition and start-up of the system; the fuel control valve is connected to the central processing unit and is used to adjust the supply of fuel; the liquid replenishing unit is connected to the central processing unit and is used to control the amount of raw material liquid added to the furnace.

8. The water gas efficient preparation system according to claim 7, characterized in that: It also includes a liquid level unit and a temperature detection unit, wherein the liquid level unit is connected to the furnace through a liquid level pipeline, and the central processing unit is connected to the liquid level unit for real-time acquisition of the liquid level in the furnace, and multiple temperature detection units are arranged in the furnace and the water-gas preparation room, and the temperature detection unit is connected to the central processing unit for detecting the temperature in the furnace and the water-gas preparation room.

9. The water gas efficient preparation system according to claim 7, characterized in that: It also includes a steam flow unit and a water-gas flow unit, wherein the steam flow unit and the water-gas flow unit are both connected to a central processor for obtaining the flow conditions of raw steam and water-gas in real time.

10. A water gas efficient preparation system according to claim 9, characterized in that: The control method during the system startup process includes the following steps: A1. The central processor controls the fuel control valve to open and the ignition device to ignite; A2, the central processing unit obtains the liquid level in the furnace through the liquid level unit, and determines whether the liquid level in the furnace reaches the preset liquid level value; if yes, proceed to step A4; if no, proceed to step A3; A3, the central processing unit controls the replenishing unit to start, replenish the raw material liquid into the furnace, and returns to step A2; A4. The central processor obtains the temperature in the furnace and the water gas preparation room in real time through the temperature detection unit; A5, the central processing unit determines whether the temperature in the water gas preparation room meets the requirements of the preset temperature range; if yes, proceed to step A6; if no, return to step A4; A6. The central processor obtains the raw material steam flow rate in real time through the steam flow unit; A7, the central processing unit determines whether the raw material steam flow rate reaches the preset steam flow rate value; if yes, proceed to step A8; if no, return to step A6; A8, the central processor obtains the water gas flow rate in real time through the water gas flow unit; A9, the central processing unit determines whether the water gas flow rate reaches the preset flow rate value; if yes, proceed to step B10; if no, return to step A8; A10, the CPU maintains the current system operation status.

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