阅读说明：本技术 一种用于羰基合成的高浓度一氧化碳可控半等温变换工艺 (controllable semi-isothermal conversion process for high-concentration carbon monoxide for oxo synthesis ) 是由 王同宝 傅亮 潘怀民 王珍 刘丹 刘芹 于 2019-08-08 设计创作，主要内容包括：本发明涉及一种用于羰基合成的高浓度一氧化碳可控半等温变换工艺,本发明的适用范围广泛,一氧化碳干基体积含量为30～90％,水/绝干气体积比为0.1～1.6的原料,本发明工艺流程短,设备数量少,控制简单,投资和运行费用低；通过设置带有控制阀的可控半等温饱和蒸汽发生系统,可以迅速、有效调节变换气温度,不仅对产汽压力无影响,而且解决了高一氧化碳含量原料气变换反应易超温、控温难的问题,最大限度的提高了副产饱和蒸汽的等级,减少了利用价值较低的低压饱和蒸汽产量；可以高压饱和蒸汽进行过热,无需再设置外部过热炉或与其他装置热联合,降低了投资和操作难度；对于催化剂末期需提温的工况,只需适当调节控制阀开度即可,便于操作。(The invention relates to a controllable semi-isothermal transformation process of high-concentration carbon monoxide for oxo synthesis, which has wide application range, wherein the volume content of a carbon monoxide dry basis is 30-90%, and the volume ratio of water to absolute dry gas is 0.1-1.6; by arranging the controllable semi-isothermal saturated steam generation system with the control valve, the temperature of the conversion gas can be quickly and effectively adjusted, the steam production pressure is not influenced, the problems that the conversion reaction of the feed gas with high carbon monoxide content is easy to exceed the temperature and the temperature is difficult to control are solved, the grade of the byproduct saturated steam is improved to the maximum extent, and the yield of the low-pressure saturated steam with low utilization value is reduced; the high-pressure saturated steam can be superheated without arranging an external superheater or thermally combining with other devices, so that the investment and the operation difficulty are reduced; and for the working condition that the temperature needs to be raised in the final stage of the catalyst, the opening degree of the control valve is only required to be properly adjusted, so that the operation is convenient.)

1. A controllable semi-isothermal conversion process of high-concentration carbon monoxide for oxo synthesis is characterized in that: comprises the following steps

The method comprises the following steps that raw gas from upstream firstly enters a No. 1 gas-liquid separator, saturated water in the raw gas is separated, process condensate at the bottom is sent to other devices for further processing, the raw gas at a top outlet firstly enters a low-pressure steam generator to produce low-pressure saturated steam as a byproduct, and then enters a No. 2 gas-liquid separator;

Separating saturated water separated out after the temperature of the raw material gas is reduced by the No. 2 gas-liquid separator, conveying the bottom process condensate to other devices for further treatment, feeding the raw material gas at the outlet of the top into a raw material gas heater, heating the temperature of the raw material gas to be above the activation temperature point of the catalyst, removing impurities and components which easily cause catalyst poisoning from the raw material gas at the outlet of the raw material gas heater through a detoxification tank according to the content of the impurities in the raw material gas, feeding the purified raw material gas into a controllable semi-isothermal reactor for carrying out shift reaction, and simultaneously obtaining a high-pressure saturated steam with a higher pressure grade as a byproduct;

The conversion gas at the outlet of the controllable semi-isothermal reactor sequentially passes through the high-pressure steam superheater, the high-pressure steam generator and the waste heat exchanger, and the conversion gas is subjected to multiple graded heat extraction and utilization, wherein the high-pressure steam superheater is used for sending out the saturated high-pressure steam produced by the high-pressure steam generator and the controllable semi-isothermal reactor after being superheated, and the waste heat exchanger is used for heating a medium which at least comprises desalted water, boiler water and low-pressure saturated steam and needs a lower temperature grade.

2. The controllable semi-isothermal shift process for the synthesis of carbonyl compounds in high concentration of carbon monoxide according to claim 1, characterized by: optionally, a section of adiabatic reactor is arranged behind the waste heat exchanger according to the requirement of the reaction depth of the shift gas, the section of adiabatic reactor comprises a common axial-radial or axial shift reactor, and the shift gas after the shift reaction again reaches the requirement of the hydrogen-carbon ratio and is sent to a downstream low-grade heat recovery device, so that the operations of further performing waste heat utilization, cooling, washing and the like on the shift gas are completed.

3. The controllable semi-isothermal shift process for the synthesis of carbonyl compounds in high concentration of carbon monoxide according to claim 1, characterized by: the other side of the raw gas heater is provided with a heat source for converting the surplus heat of the gas or the heat introduced by other devices.

4. the controllable semi-isothermal shift process for the synthesis of carbonyls in high concentration of carbon monoxide according to claim 1, 2 or 3, wherein: the controllable semi-isothermal reactor comprises a reactor shell A, the reactor shell A is shaped into a vertically extending cylinder, a central tube A15 for collecting and guiding converted gas after reaction out of the reactor is arranged in the reactor shell A along a central axis, the periphery of the central tube A15 is radially and outwardly extended and sequentially provided with an isothermal reaction area A7, an adiabatic reaction area A6 and a raw material gas inlet annular gap A8, the isothermal reaction area A7 is used for isothermal reaction of the converted gas, the adiabatic reaction area A6 is used for adiabatic reaction of the converted gas, and the raw material gas inlet annular gap A8 is used for uniformly distributing the raw material gas entering the reactor; the lower end of the isothermal reaction zone A7 is connected with a boiler water liquid collecting end socket A10, the upper end of the isothermal reaction zone A7 is connected with a steam gas collecting end socket A14, the boiler water liquid collecting end socket A10 is connected with a steam drum A2 through a boiler water descending main pipe, and the steam gas collecting end socket A14 is connected with a steam drum A2 through a steam ascending main pipe; the adiabatic reaction zone A6 is filled with a shift catalyst, the isothermal reaction zone A7 is provided with a plurality of tubes A9 that communicate from bottom to top, the tube A9 is internally communicated with boiler water for leading out reaction heat in time, and high-grade saturated steam is produced as a byproduct, the shift catalyst is filled between the tubes A9, and the catalyst is discharged from a catalyst discharge pipe A16 positioned at the lower head of the reactor.

5. The controllable semi-isothermal shift process for the synthesis of carbonyl compounds in high concentration of carbon monoxide according to claim 4, characterized by: the boiler water descending header comprises a boiler water descending header A4 and a boiler water descending header A5 which are connected in parallel, the steam ascending header comprises a steam ascending header A11 and a steam ascending header A12 which are connected in parallel, the boiler water descending header A4 is arranged corresponding to the steam ascending header A11, the boiler water descending header A5 is arranged corresponding to the steam ascending header A12, and the boiler water collecting header A10, the steam collecting header A14, the corresponding boiler water descending header A4, the steam ascending header A11 and the steam pocket A2 jointly form a saturated steam generating system; the boiler water descending header pipe A5 is provided with a control valve A3, and the boiler water descending header pipe A5, the control valve A3, a tube nest A9 connected with the control valve A3, a steam gas collecting end socket A14 and a steam ascending header pipe A12 jointly form a controllable temperature saturation steam generation system.

6. The controllable semi-isothermal shift process for the synthesis of carbonyl compounds in high concentration of carbon monoxide according to claim 4, characterized by: the isothermal reaction zone A7 and the adiabatic reaction zone A6 are in opposite positions.

7. The controllable semi-isothermal shift process for the synthesis of carbonyls in high concentration of carbon monoxide according to claim 1, 2 or 3, wherein: the controllable semi-isothermal reactor comprises a reactor shell C, the reactor shell C is shaped into a vertically extending cylinder, a central tube C14 for collecting and guiding converted gas after reaction out of the reactor is arranged in the reactor shell C along a central axis, the periphery of the central tube C14 radially and outwardly extends to be sequentially provided with an adiabatic reaction area C4, an isothermal reaction area C3 and a raw material gas inlet annular space C13, a plurality of vertically extending tubes C15 and sleeves C5 sleeved outside the tubes C15 are arranged in the isothermal reaction area C3 and used for isothermal reaction of the converted gas, the adiabatic reaction area C4 is used for adiabatic reaction of the converted gas, the raw material gas inlet annular space C13 is used for uniformly distributing the raw material gas entering the reactor, a steam gas collection chamber C12 communicated with the sleeves C5 is arranged at the top of the isothermal reaction area C3, boiler water enters the sleeves C5 of the isothermal reaction area C3 from an upper end enclosure, high-pressure saturated steam generated in the sleeve C5 is generated from a gap between the sleeve C5 and the isothermal zone array tube C15, enters the steam collection chamber C12 positioned on the upper end enclosure, and then enters the steam drum C9 through the steam riser C1.

8. The controllable semi-isothermal shift process for the synthesis of carbonyls in high concentration of carbon monoxide according to claim 1, 2 or 3, wherein: the volume content of carbon monoxide dry basis in the feed gas from upstream is 30-90%, the volume ratio of water to absolute dry gas is 0.1-1.6, and the pressure range is 1.0-9.0 MPaG.

9. The controllable semi-isothermal shift process for the synthesis of carbonyls in high concentration of carbon monoxide according to claim 1, 2 or 3, wherein: the byproduct saturated steam pressure range of the low-pressure steam generator is 0.1-2.5 MPaG; the byproduct saturated steam pressure range of the high-pressure steam generator is 2.5-8.0 MPaG.

10. The controllable semi-isothermal shift process for the synthesis of carbonyls in high concentration of carbon monoxide according to claim 2 or 3, wherein: the raw gas heater is formed by combining one or more heat exchangers in series or in parallel, and the outlet temperature of the raw synthesis gas is 150-350 ℃; the waste heat exchanger is formed by connecting one or more heat exchangers in series or in parallel, cold fluid is arranged on one side of the waste heat exchanger, transformed gas is arranged on the other side of the waste heat exchanger, and the outlet temperature is 50-400 ℃.

Technical Field

The invention relates to a controllable semi-isothermal transformation process of high-concentration carbon monoxide for oxo synthesis.

Background

The carbon monoxide shift unit has an extremely important position in a novel coal chemical industry unit, and the raw synthesis gas from an upstream gasification unit is completely or partially reacted to generate hydrogen under the action of a catalyst according to the requirement of a downstream product on the hydrogen-carbon ratio. Different product requirements have a greater impact on the set up of the conversion process flow. For plants producing hydrogen, synthetic ammonia, it is generally necessary to convert as completely as possible the carbon monoxide into hydrogen; for plants producing oxo-synthesis gas, such as methanol, ethylene glycol, synthetic oil, natural gas, etc., the shift reaction depth is shallow and the ratio of carbon monoxide to hydrogen in the synthesis gas needs to be adjusted according to product requirements. The novel continuous pressurized coal gasification technology is mainly divided into coal water slurry gasification technology (such as GE, multi-nozzle, multi-element slurry and the like) and pulverized coal gasification technology (shell, oriental furnace, space furnace, GSP and the like). The concentration of the crude synthesis gas produced by the gasification of the pulverized coal is usually 10-20% higher than that of the coal water slurry, and particularly, the crude synthesis gas produced by the gasification of the chilling type pulverized coal has high carbon monoxide concentration and high water-gas ratio of 0.7-1.0, and the conversion reaction has large driving force, so that the overtemperature of a conversion furnace is easily caused, and certain difficulty is brought to the process setting of the conversion reaction.

At present, the matched conversion process for preparing the oxo-synthesis gas from the high-concentration carbon monoxide generally comprises the following methods: traditional adiabatic process with high water-gas ratio, dynamic control of catalyst, low water-gas ratio, etc. and fast isothermal shift process developed in recent years. The high water-gas ratio conversion process is characterized in that a large amount of steam is added at one time at the inlet of a conversion device, so that the water-gas ratio is increased to more than 1.6 or even higher, the overtemperature of a first conversion furnace is avoided, but energy is greatly wasted along with the increase of the input steam amount, and the added steam is separated in a condensate mode in a downstream low-grade heat recovery stage, so that the equipment investment and the operation cost are increased; for a high water-gas ratio process, the service life of the shift catalyst is short, usually 1-2 years, the requirement of the catalyst on the sulfur content of coal is high, and if the content of hydrogen sulfide in the crude synthesis gas is low, the catalyst is easy to be subjected to counter-vulcanization. The method for controlling the CO/H2 molar ratio in the coal-to-methanol purification device with the application number of CN201110132692.1 is improved in a high water-gas ratio process, a split shift method is adopted, crude synthesis gas is divided into two parts, one part of the crude synthesis gas is added with steam to the high water-gas ratio for deep shift reaction, the excessive steam and catalyst loading amount are controlled to avoid the overtemperature of a first shift converter, and an outlet shift gas is mixed with the other unreacted crude synthesis gas after heat recovery to enter a second shift converter for reaction to reach the required hydrogen-carbon ratio. The method can better control the temperature of the shift converter, but for the shift process for producing the carbonyl synthesis gas, the saturated water contained in the upstream crude synthesis gas can meet the reaction requirement, and the supplemented steam is finally separated out of the system in a condensate mode, so that certain energy waste still exists; and the strand transformation route is complicated, the water-air ratio needs to be adjusted at any time according to the CO concentration, and certain difficulty also exists in control. Therefore, the improvement of the flow path on the high water-to-gas ratio process has certain limitations.

The catalyst dynamics control means that the temperature of a bed layer is controlled within a controllable range by reducing the catalyst loading of the first shift converter without adding steam and by a method of ensuring that the shift reaction is far from reaching the reaction balance, and boiler water is gradually added for the subsequent shift reaction according to the requirement of the reaction depth without adding steam basically. However, the method also has certain limitations, and due to the dual functions of high carbon monoxide content and high water-gas ratio, the driving force of the reaction is large, the equilibrium temperature distance is large, and the dosage of the catalyst needs to be accurately calculated. If the catalyst loading exceeds the range, the reaction depth is increased, and the overtemperature is caused; for the stage with lower start-up load, the raw synthesis gas amount is usually only half of the normal amount or even lower, and for the same catalyst loading, the over-temperature is easily caused. The Chinese utility model patent with application number of CN201020561656.8, a reactor for shift reaction of high concentration CO raw material gas, is an improvement on the basis of a dynamic control method of a catalyst, and provides a patent technology of layered filling and segmented air inlet of a shift converter. Through the splitting of raw materials, one part enters a shift converter for reaction, and the other part is taken as an excitation gas by a bypass and is mixed with the shift gas after the reaction, thereby reducing the temperature of a bed layer. Because the factors influencing the reaction temperature are more, the reaction temperature is changed due to the strand ratio, the filling amount of the catalyst, the load of the raw material gas and the fluctuation of the water-gas ratio, and the design of a control system of the method is more complex.

the low water-gas ratio carbonyl synthesis gas production is a relatively advanced process, a low-pressure waste boiler is arranged at the position of the conversion device, water brought by the crude synthesis gas can be separated out partially, the water-gas ratio is reduced to about 0.2, and therefore under the condition that the load is not changed, the conversion reaction driving force of the first conversion furnace is greatly reduced, the purpose of controlling conversion over-temperature is achieved, and meanwhile high-grade steam can be obtained as a byproduct. However, the low water-gas ratio process has a risk of methanation side reaction, so the manufacturing process of the catalyst is more complicated.

The above methods are traditional methods for preparing oxo-synthesis gas from high-concentration carbon monoxide, and with the development of conversion technology, isothermal conversion process technology mainly comprising an isothermal conversion furnace is developed, namely, heat released by conversion reaction is led out by arranging a water pipe buried in a catalyst bed layer of the conversion furnace, and under any operation conditions, especially start-up and low-load operation, a water circulation system can keep the temperature of the conversion furnace stable and simultaneously produce high-grade saturated steam as a byproduct. For the high-concentration carbon monoxide shift reaction, the isothermal shift reaction process is adopted to better solve the problem of over-temperature of the shift reaction, thereby simplifying the process, canceling the measures for controlling over-temperature such as a pre-shift furnace, a chilling line and the like, and having simple control system and good system reliability; for a conversion device for producing the oxo-gas, additional steam is not needed, and the equipment investment and the operation cost are much lower than those of the traditional process, so that the method is one of the key development directions of the conversion process in the future. For example, the axial isothermal reactor and the matched process thereof are provided in "a controllable heat-removing reactor" with the application number of CN201410662794.8 and "an isothermal transformation system for removing CO in crude gas" with the application number of CN 201520522410.2; the axial isothermal reactor and the matched process thereof are provided by 'a direct connection structure of a heat exchanger built-in cold wall type shift reactor and a shift reactor and downstream heat exchange equipment' with the application number of CN200910056717.7 and 'a high-concentration carbon monoxide isothermal shift process and a system thereof' with the application number of CN 201510107191.6.

however, the isothermal transformation technology applied at present, including the isothermal process for preparing methanol from high-concentration carbon monoxide, has the following problems: firstly, the steam of the steam drum of the isothermal shift converter is saturated steam, and superheated steam with higher quality cannot be produced. The conversion device is a steam surplus device, usually, redundant steam is used by other users in the whole plant through a steam pipe network, and condensate is easily generated due to the reduction of the temperature of saturated steam and cannot enter the pipe network. The traditional adiabatic shift converter has high outlet temperature which is usually above 400 ℃ and can overheat saturated steam, and the isothermal shift converter can only be provided with a heating furnace or be thermally combined with other devices by independently arranging the heating furnace or performing thermal combination with other devices because most of reaction heat is taken away by a water circulation system and the outlet temperature is only about 300 ℃, so that the complexity and the equipment investment of the process are increased. ② the temperature of the isothermal converter is difficult to adjust. Due to the influence of factors such as upstream load variation, water-gas ratio fluctuation, catalyst terminal temperature increase and the like, the outlet temperature of the shift converter needs to be adjusted frequently. Because the water circulation between the steam pocket and the heat exchange tube is natural circulation, namely, the water vapor circulation is formed by using the driving force generated by the static pressure head of water and the density difference of two-phase flow in the heat exchange tube, the control of removing reaction heat has certain difficulty. The invention patent CN201610194370.2 'an isothermal reactor catalyst bed temperature regulating device' proposes a method for controlling the temperature of a catalyst bed by adding a regulating valve on a saturated steam outlet pipeline and controlling the steam generation pressure of a steam drum, but the regulating method is greatly influenced by the pressure fluctuation of a steam pipe network, the temperature of saturated water can be regulated by changing the pressure of the steam drum, and the regulating method has certain hysteresis.

Disclosure of Invention

The invention aims to solve the technical problem of the prior art and provides a controllable semi-isothermal conversion process of high-concentration carbon monoxide for oxo synthesis, which can quickly and effectively adjust the conversion gas temperature, improve the grade of byproduct saturated steam, reduce the yield of low-pressure saturated steam with low utilization value and reduce the investment and operation difficulty.

The technical scheme adopted by the invention for solving the technical problems is as follows: a controllable semi-isothermal conversion process of high-concentration carbon monoxide for oxo synthesis is characterized in that: comprises the following steps

The method comprises the following steps that raw gas from upstream firstly enters a No. 1 gas-liquid separator, saturated water in the raw gas is separated, process condensate at the bottom is sent to other devices for further processing, the raw gas at a top outlet firstly enters a low-pressure steam generator to produce low-pressure saturated steam as a byproduct, and then enters a No. 2 gas-liquid separator;

The gas-liquid separator separates out saturated water separated out after the temperature of the raw material gas is reduced, the bottom process condensate is sent to other devices for further processing, the raw material gas at the outlet of the top enters a raw material gas heater, the temperature of the raw material gas is heated to be above the activation temperature point of the catalyst, the raw material gas at the outlet of the raw material gas heater removes impurities and components which easily cause catalyst poisoning through a detoxification tank according to the content of the impurities in the raw material gas, the purified raw material gas enters a controllable semi-isothermal reactor for shift reaction, and high-pressure saturated steam with higher pressure grade is produced as a byproduct;

The conversion gas at the outlet of the controllable semi-isothermal reactor sequentially passes through the high-pressure steam superheater, the high-pressure steam generator and the waste heat exchanger, and the conversion gas is subjected to multiple graded heat extraction and utilization, wherein the high-pressure steam superheater is used for sending out the saturated high-pressure steam produced by the high-pressure steam generator and the controllable semi-isothermal reactor after being superheated, and the waste heat exchanger is used for heating a medium which at least comprises desalted water, boiler water and low-pressure saturated steam and needs a lower temperature grade.

In the above scheme, according to the requirement of the reaction depth of the shift gas, optionally, a section of adiabatic reactor is arranged behind the waste heat exchanger, the section of adiabatic reactor comprises a common axial-radial or axial shift reactor, and the shift gas after the shift reaction again reaches the hydrogen-carbon ratio requirement, and then is sent to a downstream low-grade heat recovery device, so that the operations of further performing waste heat utilization, temperature reduction, washing and the like on the shift gas are completed, so as to improve the carbon monoxide conversion rate and meet the hydrogen-carbon ratio requirement of the carbonyl synthesis gas.

In order to more fully utilize energy, the heat source at the other side of the raw material gas heater is the surplus heat of the conversion gas or the heat introduced by other devices.

Preferably, the controllable semi-isothermal reactor comprises a reactor shell a, the reactor shell a is shaped as a vertically extending cylinder, a central tube a15 for collecting and guiding the converted gas after reaction out of the reactor is arranged in the reactor shell a along the central axis, the periphery of the central tube a15 is radially and outwardly extended and sequentially provided with an isothermal reaction zone a7, an adiabatic reaction zone a6 and a raw material gas inlet annular gap A8, the isothermal reaction zone a7 is used for isothermal reaction of the converted gas, the adiabatic reaction zone a6 is used for adiabatic reaction of the converted gas, and the raw material gas inlet annular gap A8 is used for uniformly distributing the raw material gas entering the reactor; the lower end of the isothermal reaction zone A7 is connected with a boiler water liquid collecting end socket A10, the upper end of the isothermal reaction zone A7 is connected with a steam gas collecting end socket A14, the boiler water liquid collecting end socket A10 is connected with a steam drum A2 through a boiler water descending main pipe, and the steam gas collecting end socket A14 is connected with a steam drum A2 through a steam ascending main pipe; the adiabatic reaction zone A6 is filled with a shift catalyst, the isothermal reaction zone A7 is provided with a plurality of tubes A9 that communicate from bottom to top, the tube A9 is internally communicated with boiler water for leading out reaction heat in time, and high-grade saturated steam is produced as a byproduct, the shift catalyst is filled between the tubes A9, and the catalyst is discharged from a catalyst discharge pipe A16 positioned at the lower head of the reactor.

Preferably, the boiler water descending main comprises a boiler water descending main A4 and a boiler water descending main A5 which are connected in parallel, the steam ascending main comprises a steam ascending main A11 and a steam ascending main A12 which are connected in parallel, the boiler water descending main A4 is arranged corresponding to the steam ascending main A11, the boiler water descending main A5 is arranged corresponding to the steam ascending main A12, and the boiler water liquid collecting header A10, the steam gas collecting header A14, the corresponding boiler water descending main A4, the steam ascending main A11 and the steam drum A2 form a saturated steam generation system; the boiler water descending header pipe A5 is provided with a control valve A3, and the boiler water descending header pipe A5, the control valve A3, a tube nest A9 connected with the control valve A3, a steam gas collecting end socket A14 and a steam ascending header pipe A12 jointly form a controllable temperature saturation steam generation system. The natural circulation ratio of water and gas in the system is controlled by adjusting the pressure drop of the control valve, so that the aim of controlling the temperature of the conversion gas in the isothermal reaction zone is fulfilled.

preferably, a bypass can be arranged between the boiler water downcomer control valve and the drum boiler water inlet pipe, the heat transfer quantity is improved by forcibly circulating external boiler water between the shift converter and the drum, and the temperature of the shift converter is controlled to be used as a supplementary measure for insufficient heat extraction of the shift converter system in a natural circulation mode during the start-up period or the low-load operation period.

as an alternative to the above, the isothermal reaction zone A7 and the adiabatic reaction zone A6 are reversed. The structure is suitable for different gasification technologies and transformation process flows, and finally the purpose that the transformation gas at the outlet of the controllable semi-isothermal reactor is not over-temperature and can overheat the self-produced saturated steam is achieved.

Preferably, the controllable semi-isothermal reactor comprises a reactor shell C, the reactor shell C is shaped as a vertically extending cylinder, a central tube C14 for collecting and guiding the shift gas after reaction out of the reactor is arranged in the reactor shell C along the central axis, the periphery of the central tube C14 extends radially outwards to be sequentially provided with an adiabatic reaction zone C4, an isothermal reaction zone C3 and a raw material gas inlet annular gap C13, a plurality of vertically extending tubes C15 and sleeves C5 sleeved outside the tubes C15 are arranged in the isothermal reaction zone C3 for isothermal reaction of shift gas, the adiabatic reaction zone C4 is used for adiabatic reaction of shift gas, the raw material gas inlet annular gap C13 is used for uniform distribution of raw material gas entering the reactor, the top of the isothermal reaction zone C3 is provided with a steam collection chamber C12 communicated with the sleeves C5, boiler water enters the sleeves C5 of the isothermal reaction zone C3 from the upper end socket, high-pressure saturated steam generated in the sleeve C5 is generated from a gap between the sleeve C5 and the isothermal zone array tube C15, enters the steam collection chamber C12 positioned on the upper end enclosure, and then enters the steam drum C9 through the steam riser C1.

preferably, the carbon monoxide dry basis volume content in the feed gas from upstream is 30-90%, the volume ratio of water to absolute dry gas is 0.1-1.6, and the pressure range is 1.0-9.0 MPaG.

Preferably, the byproduct saturated steam pressure of the low-pressure steam generator ranges from 0.1 MPaG to 2.5 MPaG; the byproduct saturated steam pressure range of the high-pressure steam generator is 2.5-8.0 MPaG.

Preferably, the raw gas heater is a combination of one or more heat exchangers connected in series or in parallel, and the outlet temperature of the raw synthesis gas is 150-350 ℃; the waste heat exchanger is formed by connecting one or more heat exchangers in series or in parallel, cold fluid is arranged on one side of the waste heat exchanger, transformed gas is arranged on the other side of the waste heat exchanger, and the outlet temperature is 50-400 ℃.

Compared with the prior art, the invention has the advantages that: the invention has wide application range, can be suitable for the carbon monoxide transformation technical process matched with the oxo synthesis (including methanol synthesis, synthetic oil, synthetic natural gas and the like) in the coal chemical industry, has the carbon monoxide dry basis volume content of 30-90 percent and the water/absolute dry gas volume ratio of 0.1-1.6, and has the advantages of short process flow, less equipment quantity, simple control and low investment and operation cost; by arranging the controllable semi-isothermal saturated steam generation system with the control valve, the temperature of the conversion gas can be quickly and effectively adjusted, the steam production pressure is not influenced, the problems that the conversion reaction of the feed gas with high carbon monoxide content is easy to exceed the temperature and the temperature is difficult to control are solved, the grade of the byproduct saturated steam is improved to the maximum extent, and the yield of the low-pressure saturated steam with low utilization value is reduced; the high-pressure saturated steam can be superheated without arranging an external superheater or thermally combining with other devices, so that the investment and the operation difficulty are reduced; and for the working condition that the temperature needs to be raised in the final stage of the catalyst, the opening degree of the control valve is only required to be properly adjusted, so that the operation is convenient.

Drawings

FIG. 1 is a partial process flow diagram of example 1 of the present invention;

FIG. 2 is a complete process flow diagram of example 1 of the present invention;

FIG. 3 is a schematic diagram of the structure of the controllable semi-isothermal reactor of FIG. 1;

FIG. 4 is a schematic structural diagram of a controllable semi-isothermal reactor in example 2 of the present invention;

FIG. 5 is a schematic structural view of a controllable semi-isothermal reactor in example 3 of the present invention;

FIG. 6 is a schematic structural diagram of a controllable semi-isothermal reactor in example 4 of the present invention.

Detailed Description

The invention is described in further detail below with reference to the accompanying examples.

as shown in fig. 1, the apparatus of the present embodiment for the carbonyl synthesis of high concentration carbon monoxide by controlled semi-isothermal shift process comprises: the system comprises a 1# gas-liquid separator 1, a low-pressure steam generator 2, a 2# gas-liquid separator 3, a raw gas heater 4, a detoxification tank 5, a controllable semi-isothermal reactor 6, a high-pressure steam superheater 7, a high-pressure steam generator 8, a waste heat exchanger 9 and an adiabatic reactor 10.

The side part of the 1# gas-liquid separator 1 is provided with a raw gas inlet, the bottom of the 1# gas-liquid separator 1 is provided with an outlet for outputting process condensate, the top of the 1# gas-liquid separator 1 is provided with an output port for feeding materials into the low-pressure steam generator 2, the output end of the low-pressure steam generator 2 is connected with a material inlet at the side part of the 2# gas-liquid separator 3, the bottom of the 2# gas-liquid separator 3 is provided with an outlet for outputting the process condensate, the top of the 2# gas-liquid separator 3 is provided with an output port for outputting the materials, the output port is connected with the input port of the raw gas heater 4, the output port of the raw gas heater 4 is connected with the input port at the top of the detoxification tank 5, the output port at the bottom of the detoxification tank 5 is connected with the input port at the bottom of the, A high-pressure steam generator 8, a waste heat exchanger 9 and an adiabatic reactor 10.

As shown in fig. 3, the controllable semi-isothermal reactor 6 includes a reactor shell a, the reactor shell a is shaped as a vertically extending cylinder, a central tube a15 for collecting and guiding the reacted shift gas out of the reactor is disposed in the reactor shell a along a central axis, an isothermal reaction zone a7, an adiabatic reaction zone a6, a raw material gas inlet annular gap A8 are sequentially disposed on the periphery of the central tube a15 in a radially outward extending manner, the isothermal reaction zone a7 is used for isothermal reaction of the shift gas, the adiabatic reaction zone a6 is used for adiabatic reaction of the shift gas, and the raw material gas inlet annular gap A8 is used for uniformly distributing the raw material gas entering the reactor; the lower end of the isothermal reaction zone A7 is connected with a boiler water liquid collecting end socket A10, the upper end of the isothermal reaction zone A7 is connected with a steam gas collecting end socket A14, the boiler water liquid collecting end socket A10 is connected with a steam drum A2 through a boiler water descending main pipe, and the steam gas collecting end socket A14 is connected with a steam drum A2 through a steam ascending main pipe; the adiabatic reaction zone A6 is filled with a shift catalyst, the isothermal reaction zone A7 is provided with a plurality of tubes A9 that communicate from bottom to top, the tube A9 is internally communicated with boiler water for leading out reaction heat in time, and high-grade saturated steam is produced as a byproduct, the shift catalyst is filled between the tubes A9, and the catalyst is discharged from a catalyst discharge pipe A16 positioned at the lower head of the reactor.

the boiler water descending header comprises a boiler water descending header A4 and a boiler water descending header A5 which are connected in parallel, the steam ascending header comprises a steam ascending header A11 and a steam ascending header A12 which are connected in parallel, the boiler water descending header A4 is arranged corresponding to the steam ascending header A11, the boiler water descending header A5 is arranged corresponding to the steam ascending header A12, and the boiler water collecting header A10, the steam collecting header A14, the corresponding boiler water descending header A4, the steam ascending header A11 and the steam pocket A2 form a saturated steam generation system; the boiler water descending header pipe A5 is provided with a control valve A3, and the boiler water descending header pipe A5, the control valve A3, a tube nest A9 connected with the control valve A3, a steam gas collecting end socket A14 and a steam ascending header pipe A12 jointly form a controllable temperature saturation steam generation system. The natural circulation ratio of water and gas in the system is controlled by adjusting the pressure drop of the control valve, so that the aim of indirectly controlling the temperature of the shift gas in the isothermal reaction zone is fulfilled.

A bypass can be arranged between the boiler water downcomer control valve A3 and a drum boiler water inlet pipe, heat transfer quantity is improved through forced circulation of external boiler water between a shift converter and a drum, temperature of the shift converter is controlled, and the bypass is used as a supplementary measure for insufficient heat extraction of the shift converter in a natural circulation mode during start-up or low-load operation.

As shown in fig. 2, the controllable semi-isothermal shift process of high concentration carbon monoxide for oxo synthesis of the present embodiment comprises the following steps:

the method comprises the following steps that (1) crude synthesis gas from a chilling process pulverized coal gasification device, with the temperature of 206 ℃, the pressure of 3.84MPaG, the carbon monoxide dry basis content of 70% and the water-gas ratio of 0.93, firstly enters a No. 1 gas-liquid separator 1, water entrained in the crude synthesis gas is separated, then passes through a No. 1 low-pressure steam generator 2, the temperature is reduced to 182 ℃ after a byproduct of 0.4MPaG saturated steam, and then enters a No. 2 gas-liquid separator 3 to separate the water;

the process condensate separated by the No. 1 gas-liquid separator 1 and the No. 2 gas-liquid separator 3 is sent to a gasification unit for treatment;

The crude synthesis gas at the top outlet of the No. 2 gas-liquid separator 3 enters a raw gas heater 4 to exchange heat with the conversion gas at the outlet of the axial-radial conversion furnace 10 to 210 ℃, then passes through a detoxification groove 5 to enter a controllable isothermal conversion furnace 6, and meanwhile, a byproduct 3.2MPaG high-pressure saturated steam is generated;

The temperature of the transformed air at the outlet of the controllable semi-isothermal transformation furnace 6 is 400 ℃, the transformed air sequentially passes through a high-pressure steam superheater 7, a high-pressure steam generator 8 and a boiler water preheater 9, the surplus heat of the transformed air is utilized to superheat the high-pressure saturated steam from the high-pressure steam generator 8 and steam drum products to 385 ℃ and preheat boiler water respectively, the temperature of the transformed air is reduced to 210 ℃, the transformed air enters an axial-radial transformation furnace 10, the temperature of the transformed air at the outlet is 260 ℃, the transformed air sequentially passes through a low-pressure steam superheater 101 and a low-pressure steam generator 102, the transformed air is utilized to produce a byproduct of 0.4MPaG low-pressure saturated steam, and the low-pressure saturated steam is superheated together with the saturated steam from a No. 1 low-pressure steam generator and then sent to;

And sending the cooled converted gas to a downstream low-grade heat recovery system.

When the raw material gas passes through the controllable semi-isothermal shift converter 6, the raw material gas enters the reactor from a raw material gas feed inlet A13, the raw material gas is uniformly distributed in an upper end enclosure of the reactor and enters an adiabatic reaction zone A6 in the shell from a raw material gas inlet annular gap A8, and after the raw material gas is subjected to shift reaction, the temperature is raised and then the raw material gas enters an isothermal reaction zone A7. Due to the heat transfer effect of the water in the tube array A9, although the shift reaction is carried out, the temperature of the shift gas is kept constant or slightly increased, and the whole shift reaction is controlled not to be over-temperature. The shift gas finally passes through the central tube a15 and exits the reactor through the shift gas outlet a 17. Boiler water from the outside forms a natural circulation system through a pipeline between the steam drum A2 and the reactor body, the density difference of the steam and the boiler water is used as a driving force, and when the saturated steam pressure output by the steam drum is certain, the conversion reaction can be controlled not to be over-temperature. Because the activity of the catalyst in the final stage of the shift reaction is low, the shift rate of the reaction is usually ensured by improving the inlet gas temperature of the raw material gas, and the shift temperature of the shift gas at the outlet of the reactor is low and the influence on the post-system is caused because the quantity of circulating water and the quantity of heat transfer water pipes of the common isothermal reactor are fixed and the quantity of the heat removed is also a fixed value. The controllable isothermal reactor is characterized in that a control valve A3 is arranged on one or more paths of boiler water descending manifolds A5, and the pressure drop of the control valve is used for controlling the natural circulation ratio of water and gas in the system, so that the aim of directly controlling the temperature of the conversion gas at the outlet of the reactor is fulfilled.