Water vapor ratio control method and controller of crude synthesis gas system and crude synthesis gas system

Abstract

The invention discloses a water vapor ratio control method of a crude synthesis gas system, a controller and the crude synthesis gas system.The crude synthesis gas system comprises a thermal deoxidization device, a gasification furnace device, a crude gas washing device, a conversion section waste heat boiler device and a flash evaporation device; the water vapor ratio control method comprises the following steps: acquiring the real-time raw gas drainage temperature and the real-time raw gas pressure of the raw gas washing device in real time; calculating a target water vapor ratio according to the real-time raw gas drainage temperature, the real-time raw gas pressure and a preset water vapor ratio function; and adjusting an adjustable variable according to the target water-steam ratio, wherein the adjustable variable comprises the deoxygenization drainage temperature of the thermal deoxygenization device, the gasification furnace drainage flow of the gasification furnace device and / or the washing drainage flow of the raw gas washing device. According to the invention, the water-vapor ratio is automatically adjusted, and the system operation stability is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of coal gasification, and in particular to a water-vapor ratio control method and a controller of a crude synthesis gas system and a crude synthesis gas system. Background Art

[0002] In the coal-to-methanol industry, coal gasification is used to produce raw coal gas. After the raw coal gas is washed, the water content in the synthesis gas at the outlet of the water scrubber must meet a certain standard. Because the synthesis gas needs to enter the subsequent conversion section for conversion reaction to adjust the C / H ratio required for methanol synthesis, the water vapor content must meet the conversion requirements. Otherwise, superheated steam needs to be added to the synthesis gas from the outside, which increases steam consumption and costs.

[0003] At present, the existing crude synthesis gas system has the following defects:

[0004] (1) Due to changes in the quality of the raw coal (such as high ash content, poor ash viscosity-temperature characteristics, high ash melting point, etc.) and changes in the CO composition of the raw gas produced after the gasification reaction, the hot spot temperature of the shift converter rises, requiring an increase in the water-steam ratio to reduce the temperature of the shift converter;

[0005] (2) Due to changes in coal quality, increased ash content and other factors, the system heat load increases, which leads to an increase in the system water circulation volume, which in turn leads to a decrease in the water-steam ratio, which cannot meet the water-steam ratio required by the conversion system. The conversion system needs to close the by-product steam regulating valve, or even adjust the conversion reaction to meet the stable operation of the existing system and ensure that the conversion furnace does not overheat or overpressure;

[0006] (3) Insufficient oxygen pressure caused by the start-up and shutdown operations, low-load operation and air separation maintenance of the gasification section leads to low system heat load and reduced water-steam ratio;

[0007] (4) The system heat load is high, the gasification flash system operates at high load, and the low-pressure flash steam entering the deaerator cannot be completely absorbed, resulting in a large amount of steam being discharged;

[0008] (5) The high heat load of the conversion furnace results in a large amount of 0.46MPa or 1.1MPa steam by-product discharged from the conversion waste heat boiler, resulting in energy waste. Summary of the invention

[0009] The purpose of the present invention is to overcome the shortcomings of the prior art crude synthesis gas system that the water-vapor ratio cannot be automatically adjusted and the steam venting leads to energy waste, and to provide a water-vapor ratio control method, a controller and a crude synthesis gas system for the crude synthesis gas system.

[0010] The technical solution of the present invention provides a method for controlling the water vapor ratio of a crude synthesis gas system, wherein the crude synthesis gas system comprises a thermal deoxygenation device, a gasification furnace device, a crude coal gas washing device, a conversion section waste heat boiler device and a flash evaporation device, and the water vapor ratio control method comprises:

[0011] Real-time acquisition of the real-time crude gas drainage temperature and real-time crude gas pressure of the crude gas scrubbing device;

[0012] Calculating a target water vapor ratio according to the real-time raw gas drainage temperature, the real-time raw gas pressure and a preset water vapor ratio function;

[0013] The adjustable variables are adjusted according to the target water vapor ratio, and the adjustable variables include the deoxidation wastewater temperature of the thermal deoxidation device, the gasification furnace wastewater flow rate of the gasification furnace device and / or the washing wastewater flow rate of the raw coal gas washing device.

[0014] In one of the optional technical solutions, adjusting the adjustable variable according to the target water vapor ratio includes:

[0015] If the target water-steam ratio increases and the real-time raw gas pressure meets the preset pressure threshold, the grey water inlet flow rate of the thermal deaerator is increased and / or the low-pressure flash steam inlet flow rate of the thermal deaerator is increased;

[0016] If the target water-steam ratio increases and the real-time raw gas pressure exceeds the preset pressure threshold, the low-pressure flash steam intake flow rate is reduced.

[0017] In one of the optional technical solutions, if the target water vapor ratio increases and the real-time raw coal gas pressure meets the preset pressure threshold, the gray water inlet flow rate of the thermal deaerator is increased and / or the low-pressure flash steam inlet flow rate of the thermal deaerator is increased, and then the method further includes:

[0018] Obtaining the real-time deoxygenation drainage pressure of the high-pressure grey water output by the thermal deoxygenation device;

[0019] If the real-time deoxygenation drainage pressure exceeds the preset water pressure threshold, the high-pressure grey water is returned to the deoxygenation bag of the thermal deoxygenation device.

[0020] In one of the optional technical solutions, if the target water vapor ratio increases and the real-time raw coal gas pressure meets the preset pressure threshold, the gray water inlet flow rate of the thermal deaerator is increased and / or the low-pressure flash steam inlet flow rate of the thermal deaerator is increased, and then the method further includes:

[0021] If the real-time raw coal gas drainage temperature does not reach the preset temperature threshold within the preset time period, the gasifier drainage flow rate and / or the washing drainage flow rate are reduced.

[0022] In one of the optional technical solutions, the crude synthesis system further includes a steam power generation device, the adjustable variable further includes a motor frequency of the steam power generation device, and the target water-steam ratio is positively correlated with the motor frequency.

[0023] The technical solution of the present invention also provides a controller for a crude synthesis gas system, comprising:

[0024] at least one processor; and,

[0025] a memory communicatively connected to the at least one processor; wherein,

[0026] The memory stores instructions that can be executed by the at least one processor. The instructions are executed by the at least one processor so that the at least one processor can perform the water vapor ratio control method as described above.

[0027] The technical solution of the present invention also provides a crude synthesis gas system, including a thermal deoxygenation device, a gasifier device, a raw gas washing device, a conversion section waste heat boiler device, a flash evaporation device, and a controller as described above, wherein the controller controls the deoxygenation drainage temperature of the thermal deoxygenation device, the gasifier drainage flow rate of the gasifier device and / or the washing drainage flow rate of the raw gas washing device.

[0028] In one of the optional technical solutions, it also includes a steam power generation device for generating electricity using the low-pressure steam discharged from the waste heat boiler device in the conversion section, and the controller controls the motor frequency of the steam power generation device.

[0029] In one of the optional technical solutions, the thermal deoxidation device includes a deoxidation bag and a box body which are interconnected.

[0030] The deaerator is provided with the low-pressure flash steam main air inlet pipe and the grey water replenishment pipe;

[0031] A low-pressure flash steam secondary air intake pipe is provided on the top of the box body, and one end of the low-pressure flash steam secondary air intake pipe extends to at least the middle and lower part of the box body, and the deaeration drainage pipe is arranged at the bottom of the box body.

[0032] In one of the optional technical solutions, a drain valve with two channels is provided on the deoxygenation drain pipe, one channel of the drain valve is connected to the raw gas washing device, and the other channel of the drain valve is connected to the deoxygenation bag. When the real-time deoxygenation drainage pressure of the deoxygenation drain pipe exceeds a preset water pressure threshold, the controller controls the other channel of the drain valve to open, so as to return the high-pressure gray water in the deoxygenation drain pipe to the deoxygenation bag.

[0033] In one of the optional technical solutions, the deaerator is cross-spaced with a first heat exchange area and a second heat exchange area, both of which are provided with a rotary film tube, and the first heat exchange area and the second heat exchange area are respectively connected to the grey water replenishment pipe.

[0034] In one of the optional technical solutions, a plurality of steam main pipes are arranged in the box body, a plurality of steam branch pipes are cross-arranged on each of the steam main pipes, and a steam hole is arranged on each of the steam branch pipes.

[0035] The above technical solution has the following beneficial effects: 1) by obtaining the real-time crude gas drainage temperature and real-time crude gas pressure of the crude gas washing device in real time, and calculating the target water vapor ratio according to the real-time crude gas drainage temperature, the real-time crude gas pressure and the preset water vapor ratio function, the adjustable variables are adjusted according to the target water vapor ratio, and the adjustable variables include the deoxidation drainage temperature of the deoxidation drainage pipe, the gasifier drainage flow of the gasifier drainage pipe and / or the washing drainage flow of the washing drainage pipe, so as to realize automatic adjustment of the water vapor ratio, avoid the problem of overheating of the catalyst bed of the shift furnace caused by poor gasification coal quality, high system heat load, etc. 1) Improve the stability of system operation; 2) Use the low-pressure flash steam of the flash evaporation device to heat the high-pressure ash water discharged from the thermal deaerator, improve the absorption of low-pressure flash steam, increase the deoxidation discharge temperature of the thermal deaerator, avoid the large-scale discharge of flash steam around 0.10MPa (G) of the thermal deaerator, eliminate the "little white dragon" phenomenon, and save energy and protect the environment; 3) By using the low-pressure steam produced as a by-product of the waste heat boiler device in the conversion section to generate electricity, the absorption of low-pressure flash steam is improved, avoid the large-scale discharge of 1.1MPa (G) steam produced as a by-product of the waste heat boiler device in the conversion section, avoid energy waste, and save energy and reduce consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The disclosure of the present invention will become more easily understood with reference to the accompanying drawings. It should be understood that these drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present invention. In the drawings:

[0037] Figure 1 A schematic diagram of the structure of a crude synthesis system provided by one embodiment of the present invention;

[0038] Figure 2 for Figure 1 The schematic diagram of the structure of the deoxygenation package shown;

[0039] Figure 3 for Figure 1 A schematic structural diagram of the box;

[0040] Figure 4 for Figure 3 Left view of

[0041] Figure 5 A working flow chart of a method for controlling the water vapor ratio of a crude synthesis system provided by one embodiment of the present invention;

[0042] Figure 6 A schematic diagram of the hardware structure of a controller of a raw synthesis gas system provided in one embodiment of the present invention.

[0043] Reference table of reference numerals:

[0044] 10-thermal deaerator; 101-deaerator bag; 1011-first heat exchange area; 1012-second heat exchange area; 1013-rotating film tube; 102-box; 1021-steam main pipe; 1022-steam branch pipe; 103-ash water replenishment pipe; 1031-ash water flow regulating valve; 104-deaerator drainage pipe; 105-low-pressure flash steam main air inlet pipe; 1051-flash steam main flow regulating valve; 106-low-pressure flash steam Steam secondary air inlet pipe; 1061-flash steam secondary flow regulating valve; 20-gasifier device; 201-gasifier drainage pipe; 2011-gasifier drainage regulating valve; 202-raw gas exhaust pipe; 30-raw gas washing device; 301-washing drainage pipe; 3011-washing drainage regulating valve; 302-washing exhaust pipe; 40-conversion section waste heat boiler device; 50-flash evaporation device; 60-controller; 70-steam power generation device. DETAILED DESCRIPTION

[0045] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings.

[0046] It is easy to understand that according to the technical solution of the present invention, without changing the essential spirit of the present invention, a variety of structural modes and implementation modes that can be replaced by those skilled in the art can be replaced with each other. Therefore, the following specific implementation modes and drawings are only exemplary descriptions of the technical solution of the present invention, and should not be regarded as the whole of the present invention or as a limitation or restriction to the technical solution of the invention.

[0047] The directional terms such as up, down, left, right, front, back, front, back, top, bottom, etc. mentioned or may be mentioned in this specification are defined relative to the structures shown in the drawings. They are relative concepts and may change accordingly according to different positions and different usage conditions. Therefore, these or other directional terms should not be interpreted as restrictive terms.

[0048] like Figure 1 As shown, a crude synthesis gas system provided by one embodiment of the present invention includes a thermal deoxygenation device 10, a gasifier device 20, a raw gas washing device 30, a conversion section waste heat boiler device 40, a flash device 50, and a controller 60. The controller 60 controls the deoxygenation wastewater temperature of the thermal deoxygenation device 10, the gasifier wastewater flow rate of the gasifier device 20 and / or the washing wastewater flow rate of the raw gas washing device 30.

[0049] The thermal deaerator 10 is provided with a low-pressure flash steam inlet pipe, a gray water supply pipe 103 and a deaerator drainage pipe 104. The low-pressure flash steam inlet pipe is connected to the external low-pressure flash steam to provide low-pressure flash steam. A flash steam flow regulating valve is provided on the low-pressure flash steam inlet pipe to control the low-pressure flash steam inlet flow. The gray water supply pipe 103 is connected to the external low-pressure gray water to provide low-pressure gray water. A gray water flow regulating valve 1031 is provided on the gray water supply pipe 103 to control the low-pressure gray water inlet flow. The thermal deaerator 10 is used to perform heat exchange between low-pressure gray water and low-pressure flash steam to generate high-pressure gray water, and discharge the high-pressure gray water into the raw gas washing device 30 through the deaerator drainage pipe 104.

[0050] The gasifier device 20 is provided with a gasifier drainage pipe 201 connected to the flash device 50 and a crude gas exhaust pipe 202 connected to the crude gas washing device 30. The gasifier drainage pipe 201 is provided with a gasifier drainage regulating valve 2011. In order to facilitate drainage, the gasifier drainage pipe 201 is arranged on the side of the bottom of the gasifier device 20. The gasifier device 20 is used to gasify the crude coal to produce crude gas and black water. The crude gas enters the crude gas washing device 30 through the crude gas exhaust pipe 202, and the black water enters the flash device 50 through the gasifier drainage pipe 201. The gasifier drainage regulating valve 2011 controls the drainage flow rate of the gasifier drainage pipe 201 entering the flash device 50.

[0051] The crude gas washing device 30 is connected to the deaeration drainage pipe 104 and the crude gas exhaust pipe 202 respectively. For the convenience of washing, the deaeration drainage pipe 104 is connected to the middle of the crude gas washing device 30. A washing drainage pipe 301 is provided at the bottom of the crude gas washing device 30, and a washing drainage regulating valve 3011 is provided on the washing drainage pipe 301. A washing exhaust pipe 302 is provided at the top of the crude gas washing device 30. The crude gas washing device 30 is used to wash the crude gas and high-pressure gray water. The washed crude gas enters the conversion section waste heat boiler device 40 through the washing exhaust pipe 302. The washed black water enters the flash evaporation device 50 through the washing drainage pipe 301 and the washing drainage regulating valve 3011. The washing drainage regulating valve 3011 controls the drainage flow rate of the washing drainage pipe 301 entering the flash evaporation device 50.

[0052] The conversion section waste heat boiler device 40 is connected to the washing exhaust pipe 302, and the conversion section waste heat boiler device 40 is used to perform heat exchange on the raw coal gas to generate low-pressure steam.

[0053] The flash evaporation device 50 is connected to the gasifier drain pipe 201, the washing drain pipe 301 and the deaerator drain pipe 104 respectively. The flash evaporation device 50 is used to flash and cool the drain of the gasifier device 20 and the raw gas washing device 30 to generate low-pressure flash steam, and use the low-pressure flash steam to heat the high-pressure ash water of the thermal deaerator 10 to improve the absorption of the low-pressure flash steam.

[0054] The controller 60 obtains the real-time crude gas drainage temperature and the real-time crude gas pressure of the scrubbing exhaust pipe 302 of the crude gas scrubbing device 30 in real time, and calculates the target water vapor ratio according to the real-time crude gas drainage temperature, the real-time crude gas pressure and the preset water vapor ratio function, and adjusts the adjustable variable according to the target water vapor ratio. The adjustable variable includes the deoxidation drainage temperature of the deoxidation drainage pipe 104, the gasifier drainage flow of the gasifier drainage pipe 201 and / or the scrubbing drainage flow of the scrubbing drainage pipe 301. The target water vapor ratio is positively correlated with the deoxidation drainage temperature, and negatively correlated with the gasifier drainage flow and the scrubbing drainage flow, that is, if the target water vapor ratio increases, the deoxidation drainage temperature increases, and the gasifier drainage flow and the scrubbing drainage flow decrease; if the target water vapor ratio decreases, the deoxidation drainage temperature decreases, and the gasifier drainage flow and the scrubbing drainage flow increase. When the target water-vapor ratio changes, the adjustable variables can be adjusted according to the set priority. The priority can be set as deaeration drainage temperature > gasification furnace drainage flow > washing drainage flow, where the deaeration drainage temperature can be achieved by adjusting the deaeration pressure, ash water make-up flow and low-pressure flash steam intake flow, and its priority can be set as deaeration pressure > ash water make-up flow = low-pressure flash steam intake flow.

[0055] Preferably, the preset water vapor ratio function is:

[0056]

[0057] Among them, CSQ1 is the target water vapor ratio; M1 is the preset first correction coefficient; M2 is the preset second correction coefficient; M3 is the preset third correction coefficient; M4 is the preset fourth correction coefficient; M5 is the preset fifth correction coefficient; P is the real-time raw gas pressure; T is the real-time raw gas drainage temperature.

[0058] Preferably, M1 is 1.0-1.4, M2 is 0.1-0.2, M3 is 0.15-0.3, M4 is 10-20, and M5 is 5000-5500.

[0059] It should be noted that the controller 60 can obtain the real-time crude gas drainage temperature and real-time crude gas pressure of the washing exhaust pipe 302 by existing methods, such as using a temperature detector or a temperature sensor to obtain the real-time crude gas drainage temperature of the washing exhaust pipe 302, and using a pressure detector or a pressure sensor to obtain the real-time crude gas pressure of the washing exhaust pipe 302.

[0060] In this embodiment, the controller obtains the real-time raw gas drainage temperature and real-time raw gas pressure of the raw gas washing device in real time, and calculates the target water vapor ratio according to the real-time raw gas drainage temperature, the real-time raw gas pressure and the preset water vapor ratio function, and adjusts the adjustable variables according to the target water vapor ratio. The adjustable variables include the deoxidation drainage temperature of the deoxidation drainage pipe, the gasification furnace drainage flow of the gasification furnace drainage pipe and / or the washing drainage flow of the washing drainage pipe, so as to realize automatic adjustment of the water vapor ratio, avoid the over-temperature problem of the catalyst bed of the conversion furnace caused by poor gasification coal quality and high system heat load, and improve the operation stability of the system. In addition, the high-pressure ash water discharged from the thermal deoxidation device is heated by the low-pressure flash steam of the flash evaporation device, so as to improve the absorption of the low-pressure flash steam, increase the deoxidation drainage temperature of the thermal deoxidation device, avoid the large-scale venting of the flash steam of the thermal deoxidation device at about 0.10MPa (G), eliminate the "little white dragon" phenomenon, and save energy and protect the environment.

[0061] In one of the optional embodiments, the raw synthesis gas system further includes a steam power generation device 70 for generating electricity using low-pressure steam discharged from the conversion stage waste heat boiler device 40 , and the controller 60 controls the motor frequency of the steam power generation device 70 .

[0062] The steam power generation device 70 is connected to the conversion section waste heat boiler device 40, and uses the low-pressure steam discharged from the conversion section waste heat boiler device 40 to generate electricity, saving energy and reducing consumption, and avoiding the waste of low-pressure steam being vented. The controller 60 controls the motor frequency of the steam power generation device 70 according to the target water-steam ratio. The target water-steam ratio is positively correlated with the motor frequency, that is, if the target water-steam ratio increases, the motor frequency increases; if the target water-steam ratio decreases, the motor frequency decreases, thereby realizing automatic adjustment of the system water-steam ratio, avoiding insufficient water-steam ratio, and improving system stability.

[0063] In one of the optional embodiments, the thermal deoxidation device 10 includes a deoxidation bag 101 and a box 102 which are interconnected, and the low-pressure flash steam inlet pipe includes a low-pressure flash steam main inlet pipe 105 and a low-pressure flash steam secondary inlet pipe 106.

[0064] The deaerator 101 is provided with a low-pressure flash steam main air inlet pipe 105 and a gray water make-up pipe 103, and the low-pressure flash steam main air inlet pipe 105 is provided with a flash steam main flow regulating valve 1051;

[0065] A low-pressure flash steam secondary air inlet pipe 106 is provided on the top of the box body 102, and one end of the low-pressure flash steam secondary air inlet pipe 106 extends to at least the middle and lower part of the box body 102. A flash steam secondary flow regulating valve 1061 is provided on the low-pressure flash steam secondary air inlet pipe 106, and the deoxygenation drainage pipe 104 is arranged at the bottom of the box body 102.

[0066] The deaerator 101 is located above the box 102. The deaerator 101 is provided with a pressure regulating valve 2015 and a pressure detector. The pressure regulating valve 2015 is used to adjust the pressure in the deaerator 101. The deaerator drainage temperature can be adjusted by the pressure regulating valve 2015. The pressure in the deaerator 101 is positively correlated with the deaerator drainage temperature. The low-pressure flash steam main air intake pipe 105 can be arranged at the lower part of the deaerator 101, so that the low-pressure flash steam enters the liquid level of the deaerator 101 through the low-pressure flash steam main air intake pipe 105 to perform deoxidation and water vapor heat exchange.

[0067] One end of the low-pressure flash steam secondary air inlet pipe 106 passes through the top of the box 102 and is connected to the external low-pressure flash steam, and the other end of the low-pressure flash steam secondary air inlet pipe 106 extends to the lower middle part or the bottom of the box 102. The low-pressure flash steam enters below the liquid level of the box 102 through the low-pressure flash steam secondary air inlet pipe 106 for deoxygenation and water vapor heat exchange.

[0068] In one of the optional embodiments, a drain valve with two channels is provided on the deoxygenation drain pipe 104, one channel of the drain valve is connected to the raw gas washing device 30, and the other channel of the drain valve is connected to the deoxygenation bag 101. When the real-time deoxygenation drainage pressure of the deoxygenation drain pipe 104 exceeds the preset water pressure threshold, the controller 60 controls the other channel of the drain valve to open, so as to return the high-pressure gray water in the deoxygenation drain pipe 104 to the deoxygenation bag 101.

[0069] The drain valve has two channels, one of which is connected to the raw gas washing device 30, and the other is connected to the deaerator bag 101. The other channel of the drain valve is in a normally closed state. When it is detected that the real-time deaerator drainage pressure exceeds the preset water pressure threshold, the controller 60 controls the other channel of the drain valve to open, so that the deaerator drainage pipe 104 is connected to the deaerator bag 101 through the other channel, and the high-pressure gray water in the deaerator drainage pipe 104 flows back to the deaerator bag 101, thereby improving the water vapor ratio of the raw synthesis gas system.

[0070] In one of the optional embodiments, Figure 2 As shown, the deoxygenation bag 101 is cross-spaced with a first heat exchange area 1011 and a second heat exchange area 1012, both of which are provided with a rotary film tube 1013, and the first heat exchange area 1011 and the second heat exchange area 1012 are respectively connected to the gray water replenishment pipe 103.

[0071] The deoxidation bag 101 is provided with a rotary film tube 1013 to improve the heat exchange effect. The rotary film tube 1013 forms the deoxidation bag 101 into a first heat exchange area 1011 and a second heat exchange area 1012. The first heat exchange area 1011 and the second heat exchange area 1012 are cross-spaced and distributed along the circumferential direction of the deoxidation bag 101. The number of the rotary film tubes 1013 in the first heat exchange area 1011 and the second heat exchange area 1012 is different, which is convenient for regulating the heat exchange area between water vapor and improving the heat exchange efficiency.

[0072] In one of the optional embodiments, Figure 2 As shown, in order to improve heat exchange uniformity, the spiral film tubes 1013 located in the oppositely arranged first heat exchange regions 1011 are symmetrically distributed, and the spiral film tubes 1013 located in the oppositely arranged second heat exchange regions 1012 are symmetrically distributed.

[0073] Preferably, the number of the first heat exchange region 1011 and the second heat exchange region 1012 is two. When in use, the rotary film tube 1013 in the first heat exchange region 1011 is in use, and the rotary film tube 1013 in the second heat exchange region 1012 is in standby. When the target water vapor ratio increases, the controller 60 turns on the rotary film tube 1013 in the second heat exchange region 1012, so that the rotary film tube 1013 in the second heat exchange region 1012 is also in use, thereby increasing the deoxygenated wastewater temperature and improving the water vapor ratio.

[0074] In one of the optional embodiments, Figure 3 and Figure 4 As shown, a plurality of steam main pipes 1021 are arranged in the box body 102, and a plurality of steam branch pipes 1022 are cross-arranged on each steam main pipe 1021. Each steam branch pipe 1022 is provided with a steam hole, and the steam holes are spirally distributed on the steam branch pipe 1022, so as to further increase the heat exchange area and improve the heat exchange effect.

[0075] Preferably, in order to improve system stability, the number of the steam main pipes 1021 is 1-4, the number of the steam branch pipes 1022 is 6-18, and the number of the steam holes is 4-12.

[0076] Based on the above embodiments, Figure 5 As shown, a method for controlling the water vapor ratio of a crude synthesis system provided by one embodiment of the present invention includes:

[0077] Step S501: obtaining the real-time crude gas drainage temperature and the real-time crude gas pressure of the crude gas exhaust pipe of the crude gas scrubbing device in real time;

[0078] Step S502: Calculate the target water vapor ratio according to the real-time raw gas drainage temperature, the real-time raw gas pressure and a preset water vapor ratio function;

[0079] Step S503: adjusting adjustable variables according to the target water vapor ratio, the adjustable variables including the deoxidation wastewater temperature of the thermal deoxidation device, the gasification furnace wastewater flow rate of the gasification furnace device and / or the washing wastewater flow rate of the raw coal gas washing device.

[0080] Specifically, when the crude synthesis gas system is running, the controller executes step S501 to obtain the real-time crude gas drainage temperature and real-time crude gas pressure of the crude gas exhaust pipe of the crude gas washing device in real time, such as using a temperature detector or a temperature sensor to obtain the real-time crude gas drainage temperature of the washing exhaust pipe, and using a pressure detector or a pressure sensor to obtain the real-time crude gas pressure of the washing exhaust pipe; then executes step S502 to calculate the target water vapor ratio according to the real-time crude gas drainage temperature, the real-time crude gas pressure and the preset water vapor ratio function; finally, executes step S503 to adjust the adjustable variable according to the target water vapor ratio, and the target water vapor ratio is positively correlated with the adjustable variable, that is, if the target water vapor ratio increases, the adjustable variable increases; if the target water vapor ratio decreases, the adjustable variable decreases. The adjustable variables include the deoxygenation drainage temperature of the deoxygenation drainage pipe, the gasifier drainage flow of the gasifier drainage pipe, and / or the washing drainage flow of the washing drainage pipe. The target water vapor ratio is positively correlated with the deaeration drainage temperature, and negatively correlated with the gasifier drainage flow and the washing drainage flow, that is, if the target water vapor ratio increases, the deaeration drainage temperature increases, and the gasifier drainage flow and the washing drainage flow decrease; if the target water vapor ratio decreases, the deaeration drainage temperature decreases, and the gasifier drainage flow and the washing drainage flow increase. When the target water vapor ratio changes, the adjustable variables can be adjusted according to the set priority, and the priority can be set as deaeration drainage temperature>gasifier drainage flow>washing drainage flow, where the deaeration drainage temperature can be achieved by adjusting the deaeration pressure, the ash water makeup flow and the low-pressure flash steam intake flow, and its priority can be set as deaeration pressure>ash water makeup flow=low-pressure flash steam intake flow.

[0081] Preferably, the preset water vapor ratio function is:

[0082]

[0083] Among them, CSQ1 is the target water vapor ratio; M1 is the preset first correction coefficient; M2 is the preset second correction coefficient; M3 is the preset third correction coefficient; M4 is the preset fourth correction coefficient; M5 is the preset fifth correction coefficient; P is the real-time raw gas pressure; T is the real-time raw gas drainage temperature.

[0084] Preferably, M1 is 1.0-1.4, M2 is 0.1-0.2, M3 is 0.15-0.3, M4 is 10-20, and M5 is 5000-5500.

[0085] In this embodiment, the real-time crude gas drainage temperature and real-time crude gas pressure of the crude gas washing device are obtained in real time, and the target water vapor ratio is calculated according to the real-time crude gas drainage temperature, the real-time crude gas pressure and the preset water vapor ratio function, and the adjustable variable is adjusted according to the target water vapor ratio, so as to achieve automatic adjustment of the water vapor ratio, avoid the problem of overheating of the catalyst bed of the conversion furnace caused by poor gasification coal quality and high system heat load, and improve the operation stability of the system. In addition, the high-pressure ash water discharged from the thermal deoxidation device is heated by the low-pressure flash steam of the flash evaporation device, so as to improve the absorption of the low-pressure flash steam, increase the deoxidation drainage temperature of the thermal deoxidation device, avoid the large-scale venting of flash steam around 0.10MPa (G) of the thermal deoxidation device, eliminate the "little white dragon" phenomenon, and save energy and protect the environment.

[0086] In one of the optional embodiments, step S503 includes:

[0087] If the target water-steam ratio increases and the real-time raw gas pressure meets the preset pressure threshold, the grey water inlet flow rate of the thermal deaerator is increased and / or the low-pressure flash steam inlet flow rate of the thermal deaerator is increased;

[0088] If the target water-steam ratio increases and the real-time raw gas pressure exceeds the preset pressure threshold, the low-pressure flash steam intake flow rate is reduced.

[0089] Specifically, when the target water-vapor ratio increases and the real-time raw coal gas pressure is within the preset pressure threshold range, the controller controls the opening of the ash non-water make-up flow valve set on the ash water make-up pipe to increase, thereby increasing the ash water inlet flow rate, and / or controls the opening of the flash steam main flow regulating valve and the flash steam secondary flow regulating valve to increase, thereby increasing the steam inlet flow rate of the low-pressure valve, thereby increasing the deoxygenation drainage temperature and improving the water-vapor ratio of the raw synthesis gas system.

[0090] In one of the optional embodiments, if the target water-steam ratio increases and the real-time raw gas pressure meets the preset pressure threshold, the gray water inlet flow rate of the thermal deaerator is increased and / or the low-pressure flash steam inlet flow rate of the thermal deaerator is increased, and then the following is further included:

[0091] Obtain the real-time deoxygenation drainage pressure of the high-pressure grey water output by the thermal deoxygenation device;

[0092] If the real-time deaeration drainage pressure exceeds the preset water pressure threshold, the high-pressure grey water will flow back to the deaeration bag of the thermal deaerator.

[0093] Specifically, when the target water-vapor ratio increases and the real-time raw coal gas pressure meets the preset pressure threshold, the controller obtains the real-time deoxygenation drainage pressure of the deoxygenation drainage pipe in real time. When the real-time deoxygenation drainage pressure exceeds the preset water pressure threshold, the controller controls the other channel of the drain valve with two channels arranged on the deoxygenation drainage pipe to open, and returns the high-pressure gray water in the deoxygenation drainage pipe to the deoxygenation bag, thereby increasing the deoxygenation drainage temperature and improving the water-vapor ratio of the raw synthesis gas system.

[0094] In one of the optional embodiments, if the target water-steam ratio increases and the real-time raw gas pressure meets the preset pressure threshold, the gray water inlet flow rate of the thermal deaerator is increased and / or the low-pressure flash steam inlet flow rate of the thermal deaerator is increased, and then the following is further included:

[0095] If the real-time raw coal gas drainage temperature does not reach the preset temperature threshold within the preset time period, the gasifier drainage flow rate and / or the washing drainage flow rate are reduced.

[0096] Specifically, when the target water-vapor ratio increases and the real-time raw gas pressure meets the preset pressure threshold, the controller detects the real-time raw gas drainage temperature in real time. If the real-time raw gas drainage temperature does not reach the preset temperature threshold within the preset time period, the controller controls the opening of the gasifier drainage regulating valve and / or the washing drainage regulating valve to reduce, thereby reducing the gasifier drainage flow and / or the washing drainage flow, thereby increasing the water-vapor ratio of the raw synthesis gas system.

[0097] In one of the optional embodiments, the crude synthesis system further includes a steam power generation device, the adjustable variable further includes a motor frequency of the steam power generation device, and the target water-steam ratio is positively correlated with the motor frequency.

[0098] Specifically, when the target water-steam ratio changes, the controller adjusts the motor frequency of the steam power generation device to adapt to changes in operating conditions. For example, when the target water-steam ratio increases to a certain level, the amount of low-pressure steam produced as a by-product of the waste heat boiler device in the conversion section increases relatively, and the motor frequency is increased for power generation, thereby improving the absorption of low-pressure flash steam and increasing the deaeration drainage temperature. This avoids the discharge of large amounts of flash steam of around 0.10 MPa (G) from the thermal deaerator and 1.1 MPa (G) steam produced as a by-product of the waste heat boiler device in the conversion section, thereby eliminating the "little white dragon" phenomenon, avoiding energy waste, and saving energy and reducing consumption.

[0099] Taking the coal-to-methanol industry with an annual output of 2.3 million tons of methanol as an example, after the ash water of the gasification system is thermally deoxygenated, the ash water recovers heat from the low-pressure flash steam, and the deoxygenated water temperature is increased from the current 100°C to 120°C. The water circulation volume in the thermal deoxygenation device is calculated as 1000t / h, and the specific heat capacity of water is 4.2KJ / kg / ℃. According to the heat balance, it can be concluded that the heat Q recovered from the low-pressure flash steam is 84000MJ / h, which is equivalent to 2.866t / h of standard coal. Assuming that the market price of each ton of standard coal is 600 yuan and the device runs 8000 hours per year, the economic benefit of recovering low-pressure flash steam is: 13.7568 million yuan / year. At the same time, providing a sufficient water-vapor ratio ensures the service life of the conversion catalyst to a certain extent, alleviates the exothermic effect brought by the conversion reaction to a certain extent, and avoids over-temperature operation.

[0100] like Figure 6 As shown, a hardware structure diagram of a controller of a raw synthesis gas system provided by an embodiment of the present invention includes:

[0101] at least one processor 601; and,

[0102] A memory 602 is communicatively connected to at least one processor 601; wherein,

[0103] The memory 602 stores instructions that can be executed by at least one processor 601. The instructions are executed by at least one processor 601 so that the at least one processor 601 can execute the water vapor ratio control method in any of the above method embodiments.

[0104] Figure 6 A processor 601 is taken as an example.

[0105] The electronic device is preferably an Electronic Control Unit (ECU).

[0106] The electronic device may further include: an input device 603 and an output device 604 .

[0107] The processor 601, the memory 602, the input device 603 and the output device 604 may be connected via a bus or other means, and the figure takes the connection via a bus as an example.

[0108] The memory 602, as a non-volatile computer-readable storage medium, can be used to obtain non-volatile software programs, non-volatile computer executable programs and modules, such as program instructions / modules corresponding to the water vapor ratio control method in the embodiment of the present application, for example, Figure 5The processor 601 executes various functional applications and data processing by running the non-volatile software programs, instructions and modules acquired in the memory 602, that is, the water vapor ratio control method in the above embodiment is implemented.

[0109] The memory 602 may include an acquisition program area and an acquisition data area, wherein the acquisition program area may acquire an operating system and an application required by at least one function; the acquisition data area may acquire data created according to the use of the water vapor ratio control method, etc. In addition, the memory 602 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 602 may optionally include a memory remotely arranged relative to the processor 601, and these remote memories may be connected to a device for executing the water vapor ratio control method via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0110] The input device 603 can receive user clicks and generate signal inputs related to user settings and function controls of the water vapor ratio control method. The output device 604 can include display devices such as display screens.

[0111] The one or more modules are acquired in the memory 602, and when being run by the one or more processors 601, the water vapor ratio control method in any of the above method embodiments is executed.

[0112] The above-mentioned product can execute the method provided in the embodiment of the present application, and has the functional modules and beneficial effects corresponding to the execution method. For technical details not fully described in this embodiment, please refer to the method provided in the embodiment of the present application.

[0113] The above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention, rather than to limit them. Although the embodiments of the present invention are described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some of the technical features therein by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling the water vapor ratio of a crude synthesis gas system, wherein the crude synthesis gas system comprises a thermal deoxidation device, a gasification furnace device, a crude gas washing device, a conversion section waste heat boiler device and a flash evaporation device, It is characterized in that The water vapor ratio control method comprises: Real-time acquisition of the real-time crude gas drainage temperature and real-time crude gas pressure of the crude gas scrubbing device; Calculating a target water vapor ratio according to the real-time raw gas drainage temperature, the real-time raw gas pressure and a preset water vapor ratio function; The adjustable variables are adjusted according to the target water vapor ratio, and the adjustable variables include the deoxidation wastewater temperature of the thermal deoxidation device, the gasification furnace wastewater flow rate of the gasification furnace device and / or the washing wastewater flow rate of the raw coal gas washing device.

2. The water vapor ratio control method according to claim 1, It is characterized in that The adjusting the adjustable variable according to the target water vapor ratio comprises: If the target water-steam ratio increases and the real-time raw gas pressure meets the preset pressure threshold, the grey water inlet flow rate of the thermal deaerator is increased and / or the low-pressure flash steam inlet flow rate of the thermal deaerator is increased; If the target water-steam ratio increases and the real-time raw gas pressure exceeds the preset pressure threshold, the low-pressure flash steam intake flow rate is reduced.

3. The water vapor ratio control method according to claim 2, It is characterized in that If the target water-steam ratio increases and the real-time raw gas pressure meets the preset pressure threshold, the gray water inlet flow rate of the thermal deoxygenator is increased and / or the low-pressure flash steam inlet flow rate of the thermal deoxygenator is increased, and then the method further includes: Obtaining the real-time deoxygenation drainage pressure of the high-pressure grey water output by the thermal deoxygenation device; If the real-time deoxygenation drainage pressure exceeds the preset water pressure threshold, the high-pressure grey water is returned to the deoxygenation bag of the thermal deoxygenation device.

4. The water vapor ratio control method according to claim 2, It is characterized in that If the target water-steam ratio increases and the real-time raw gas pressure meets the preset pressure threshold, the gray water inlet flow rate of the thermal deoxygenator is increased and / or the low-pressure flash steam inlet flow rate of the thermal deoxygenator is increased, and then the method further includes: If the real-time raw coal gas drainage temperature does not reach the preset temperature threshold within the preset time period, the gasifier drainage flow rate and / or the washing drainage flow rate are reduced.

5. The water vapor ratio control method according to any one of claims 1 to 4, It is characterized in that The crude synthesis system further includes a steam power generation device, the adjustable variable further includes a motor frequency of the steam power generation device, and the target water-steam ratio is positively correlated with the motor frequency.

6. A controller for a raw synthesis gas system, It is characterized in that include: at least one processor; as well as, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the water vapor ratio control method according to any one of claims 1 to 5.

7. A crude synthesis gas system, It is characterized in that It comprises a thermal deoxidation device, a gasifier device, a raw gas washing device, a conversion section waste heat boiler device, a flash evaporation device, and a controller as claimed in claim 6, wherein the controller controls the deoxidation wastewater temperature of the thermal deoxidation device, the gasifier wastewater flow rate of the gasifier device and / or the washing wastewater flow rate of the raw gas washing device.

8. The raw synthesis gas system according to claim 7, It is characterized in that It also includes a steam power generation device for generating electricity using low-pressure steam discharged from the conversion section waste heat boiler device, and the controller controls the motor frequency of the steam power generation device.

9. The raw synthesis gas system according to claim 7 or 8, It is characterized in that The thermal deoxidation device comprises a deoxidation bag and a box body which are interconnected. The deaerator is provided with the low-pressure flash steam main air inlet pipe and the grey water replenishment pipe; A low-pressure flash steam secondary air intake pipe is provided on the top of the box body, and one end of the low-pressure flash steam secondary air intake pipe extends to at least the middle and lower part of the box body, and the deaeration drainage pipe is arranged at the bottom of the box body.

10. The raw synthesis gas system according to claim 9, It is characterized in that The deoxygenation drain pipe is provided with a drain valve with two channels, one channel of the drain valve is connected to the raw gas washing device, and the other channel of the drain valve is connected to the deoxygenation bag. When the real-time deoxygenation drainage pressure of the deoxygenation drain pipe exceeds a preset water pressure threshold, the controller controls the other channel of the drain valve to open, so as to return the high-pressure gray water in the deoxygenation drain pipe to the deoxygenation bag.

11. The raw synthesis gas system according to claim 9, It is characterized in that The deaerator bag is provided with a first heat exchange area and a second heat exchange area at a cross interval. The first heat exchange area and the second heat exchange area are both provided with a rotary film tube. The first heat exchange area and the second heat exchange area are respectively connected to the gray water replenishment pipe.

12. The raw synthesis gas system according to claim 9, It is characterized in that A plurality of steam main pipes are arranged in the box body, a plurality of steam branch pipes are cross-arranged on each of the steam main pipes, and a steam hole is arranged on each of the steam branch pipes.

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