Multi-stage series adsorption enhanced water-gas shift reaction system and regulation and control method

Abstract

The invention discloses a multi-stage series adsorption enhanced water-gas shift reaction system and a regulation and control method, and is applied to the technical field of synthesis gas treatment. The reaction system comprises a gas inlet monitoring module used for acquiring components and process parameters of input crude synthesis gas; the multi-stage series reaction module comprises a plurality of reaction regeneration units which are connected in series, a catalyst and an adsorbent are filled in a reactor, and independent temperature adjusting equipment is arranged; the central control module is used for acquiring real-time data of the system, calculating optimal reaction parameters of each stage of reaction regeneration unit and a split ratio required by the system, and executing the optimal reaction parameters and the split ratio; and the mixing output module is used for mixing the outlet gas of the multi-stage cascade reaction module and the original crude synthesis gas and outputting the synthesis gas with the target component proportion. According to the invention, CO conversion and CO2 removal are more efficiently completed through step-by-step deepening transformation and adsorption of multi-stage cascade reaction, the adaptability to complex inlet gas components is improved, and wide-range, high-precision and continuous adjustment of the component proportion is realized.

Description

Technical Field

[0001] This invention relates to the field of syngas treatment technology, and more specifically to a multi-stage series adsorption enhanced water-gas shift reaction system and its control method. Background Technology

[0002] Syngas (mainly composed of H2 and CO) is a key intermediate in coal chemical, natural gas chemical, and biomass conversion processes. Its hydrogen-to-carbon ratio (H2 / CO) directly affects the process efficiency and economic benefits of downstream synthetic products (such as methanol, Fischer-Tropsch synthetic oil, and olefins). Different downstream processes have specific requirements for the hydrogen-to-carbon ratio of syngas (e.g., methanol synthesis requires approximately 2:1, while Fischer-Tropsch synthesis has a wider range). Water-gas shift (WGS) reaction is the main method for adjusting the H2 / CO ratio of syngas in industry, but this reaction is limited by thermodynamic equilibrium, requires multi-stage processing, and produces a large amount of CO2 that needs to be separated, resulting in a complex process and high energy consumption. Adsorption-enhanced water-gas shift (SEWGS) technology couples the WGS reaction with in-situ CO2 adsorption (usually using adsorbents such as CaO), breaking the equilibrium limitation through Le Chatelier's principle, and can obtain high-purity H2 in a single-stage reaction while simultaneously capturing CO2.

[0003] However, existing SEWGS reaction systems involve single-stage deep conversion with limited control capabilities and the ability to compensate for fluctuations in the inlet gas composition. CO2 capture is concentrated in a single reaction stage, resulting in high adsorbent loads and room for efficiency optimization. Control strategies primarily target the split ratio of the crude syngas, lacking fine-grained control over the internal reaction process and hindering rapid and precise tracking and adjustment of H2 / CO over a wide range. Therefore, providing a multi-stage tandem adsorption-enhanced water-gas shift reaction system and its control method is a problem urgently needing to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the present invention provides a multi-stage series adsorption enhanced water-gas shift reaction system and control method, which enables wide-range, high-precision, and continuous intelligent control of the reaction process and syngas ratio through multi-stage series reaction units, thereby achieving efficient staged CO2 capture.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A multi-stage series adsorption-enhanced water-gas shift reaction system includes: The intake monitoring module is used to acquire the composition and process parameters of the input crude syngas; The multi-stage series reaction module, connected to the intake monitoring module, includes multiple series reaction and regeneration units. The reactor of each reaction and regeneration unit is filled with catalyst and adsorbent, and each reaction and regeneration unit is equipped with an independent temperature control device. The central control module, connected to the intake monitoring module, the multi-stage series reaction module, and the mixed output module, is used to acquire real-time data of the system, calculate the optimal reaction parameters of each stage of the reaction regeneration unit, and the required split ratio of the system. The mixing output module, connected to the intake monitoring module and the multi-stage series reaction module, is used to mix the outlet gas of the multi-stage series reaction module and the raw crude syngas output with the target component ratio to produce syngas.

[0006] Optionally, the intake monitoring module includes an intake regulating valve, a gas composition analyzer, and a flow meter connected in sequence. The flow meter is connected to a multi-stage series reaction module. A temperature sensor and a pressure sensor are installed between the gas composition analyzer and the flow meter. The intake regulating valve is also connected to the mixing output module through a bypass regulating valve.

[0007] Optionally, in a multi-stage series reaction module, the reaction temperature, the catalytic effect of the catalyst, and the adsorption capacity of the adsorbent are progressively increased in multiple reaction regeneration units.

[0008] Optionally, the reaction regeneration unit includes: a first reactor and a second reactor connected in parallel, an inlet switching valve, and an outlet switching valve. The inlet switching valve is connected to the inlet pipes of the first reactor and the second reactor. A gas composition analyzer is also installed before the inlet switching valve. The outlet switching valve is connected to the outlet pipes of the first reactor and the second reactor. Both the first reactor and the second reactor are equipped with a gas inlet valve, a gas outlet valve, a water vapor inlet valve, an inert gas inlet valve, a heating device, and a temperature sensor. A flow meter is installed at all inlet valves.

[0009] Optionally, the central control module includes a data acquisition unit, a parameter calculation unit, and an execution scheduling unit. The data acquisition unit receives the target syngas component ratio, the composition and process parameters of the crude syngas, and the gas composition and process parameters after each stage of reaction. The parameter calculation unit calculates the optimal reaction parameters and the required split ratio of the system based on the received data. The optimal reaction parameters include the reaction temperature and water vapor addition amount for each stage. The execution scheduling unit adjusts the reaction temperature, water vapor addition amount, and real-time split ratio according to the calculation results.

[0010] Optionally, the mixing output module includes a mixing valve, a mixer, and a gas composition analyzer connected in sequence. The mixing valve is connected to the inlet monitoring module and the multi-stage series reaction module to control the mixing ratio of the outlet gas and the raw crude syngas.

[0011] A method for regulating water-gas shift reaction enhanced by multi-stage tandem adsorption, utilizing the aforementioned multi-stage tandem adsorption enhanced water-gas shift reaction system, includes the following steps: S1. Obtain the target syngas component ratio, crude syngas composition, and process parameters; S2. Calculate and set the optimal reaction parameters for each stage of the reactor and the required split ratio of the system based on the acquired data; S3. The crude syngas passes through a multi-stage series reaction module in sequence. In each stage, it undergoes a water-gas shift reaction with the added water vapor, and the generated CO2 is captured by the adsorbent. S4. The outlet gas of the last stage series reaction module enters the mixer and is mixed with the original crude syngas according to the target gas component ratio in the calculation results.

[0012] Optionally, the saturation state of the adsorbent in the reactors of each series reaction module is continuously monitored during the reaction process. When the adsorbent is close to saturation, the regeneration program of the corresponding reactor is started, and the reactor is switched to another reactor in the reaction regeneration unit to carry out the adsorption-enhanced water-gas shift reaction.

[0013] As can be seen from the above technical solution, compared with the prior art, the present invention provides a multi-stage tandem adsorption enhanced water-gas shift reaction system and control method, which has the following beneficial effects: 1. This invention uses a multi-stage series structure to decompose the overall reaction process into multiple independently optimizable sub-stages. By adjusting the temperature of each stage individually and coordinating the control, it achieves wide-range, high-precision continuous dynamic adjustment of the H2 / CO ratio, resulting in a faster response speed. 2. This invention reduces the single-stage adsorption load and improves the adsorbent utilization efficiency through a staged CO2 capture strategy; 3. This invention uses real-time data from the entire process for reaction control, which can adjust and compensate for fluctuations in the composition and flow rate of the upstream intake air, respond to changes in downstream product demand, and output extremely stable product gas. 4. This invention ensures the continuity of the adsorption and regeneration process through the parallel alternating operation mode of the two reactors. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the multi-stage series adsorption-enhanced water-gas shift reaction system of the present invention; Figure 2 This is a schematic diagram of the gas reaction process of the water-gas shift reaction system of the present invention; Figure 3 This is a schematic diagram of the reaction regeneration unit of the present invention; Figure 4This is a flowchart of the multi-stage series adsorption-enhanced water-gas shift regulation method of the present invention. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] This invention discloses a multi-stage tandem adsorption-enhanced water-gas shift reaction system, such as... Figure 1 and Figure 2 As shown, it includes: The intake monitoring module is used to acquire the composition and process parameters of the input crude syngas; The multi-stage series reaction module, connected to the intake monitoring module, includes multiple series reaction and regeneration units. The reactor of each reaction and regeneration unit is filled with catalyst and adsorbent, and each reaction and regeneration unit is equipped with an independent temperature control device. The central control module, connected to the intake monitoring module, the multi-stage series reaction module, and the mixed output module, is used to acquire real-time data of the system, calculate the optimal reaction parameters of each stage of the reaction regeneration unit, and the required split ratio of the system. The mixing output module, connected to the intake monitoring module and the multi-stage series reaction module, is used to mix the outlet gas of the multi-stage series reaction module and the raw crude syngas output with the target component ratio to produce syngas.

[0018] Furthermore, the intake monitoring module includes an intake regulating valve, a gas composition analyzer, and a flow meter connected in sequence. The flow meter is connected to a multi-stage series reaction module. A temperature sensor and a pressure sensor are installed between the gas composition analyzer and the flow meter. The intake regulating valve is also connected to the mixing output module through a bypass regulating valve.

[0019] Furthermore, in the multi-stage series reaction module, the reaction temperature, the catalytic effect of the catalyst, and the adsorption capacity of the adsorbent in the multiple reaction regeneration units are gradually increased.

[0020] In this embodiment of the invention, the reaction temperature of the first-stage reaction regeneration unit is set to 600-650°C, and the temperature of the last stage is set to 700-750°C. The first-stage reactor can be filled with a highly active catalyst and a fast-adsorption type adsorbent, and the last-stage reactor can be filled with a highly stable catalyst and a high-capacity, highly selective adsorbent to achieve deep CO2 removal.

[0021] Furthermore, such as Figure 3As shown, the reaction regeneration unit includes: a first reactor and a second reactor connected in parallel, an inlet switching valve, and an outlet switching valve. The inlet switching valve is connected to the inlet pipes of the first reactor and the second reactor. A gas composition analyzer is also installed before the inlet switching valve. The outlet switching valve is connected to the outlet pipes of the first reactor and the second reactor. Both the first reactor and the second reactor are equipped with a gas inlet valve, a gas outlet valve, a water vapor inlet valve, an inert gas inlet valve, a heating device, and a temperature sensor. A flow meter is installed at all inlet valves.

[0022] Furthermore, the central control module includes a data acquisition unit, a parameter calculation unit, and an execution scheduling unit. The data acquisition unit receives the target syngas component ratio, the composition and process parameters of the crude syngas, and the gas composition and process parameters after each stage of reaction. The parameter calculation unit calculates the optimal reaction parameters and the required split ratio of the system based on the received data. The optimal reaction parameters include the reaction temperature and water vapor addition amount for each stage. The execution scheduling unit adjusts the reaction temperature, water vapor addition amount, and real-time split ratio according to the calculation results.

[0023] In this embodiment of the invention, the formula for the parameter calculation unit to calculate the required split ratio of the system is: ; In the formula, For the target H2 / CO, To determine the required split ratio for the system, calculate the required split ratio based on the given target H2 / CO ratio. The total feed molar flow rate, For crude syngas Proportion, For crude syngas Proportion, The conversion rate of CO within the reactor; The parameter calculation unit calculates the optimal reaction parameters as follows: Real-time data is read from all sensors and flow meters. Using a state observer (such as a Kalman filter) and a reaction model, key states that cannot be directly measured are estimated, such as the instantaneous saturation of the adsorbent in each reactor stage (adsorbent saturation can be determined based on the outlet CO2 content) and the actual activity of the catalyst. The temperature and steam addition rate of each reactor stage are used as decision variables. The objective function is to minimize the difference between the actual output syngas H2 / CO ratio and the target ratio. The optimization problem is solved, and the real-time setpoints obtained from the optimization calculation are sent to the corresponding equipment for adjustment.

[0024] Furthermore, the mixing output module includes a mixing valve, a mixer, and a gas composition analyzer connected in sequence. The mixing valve is connected to the inlet monitoring module and the multi-stage series reaction module to control the mixing ratio of the outlet gas and the raw crude syngas.

[0025] and Figure 1 Corresponding to the aforementioned reaction system, this invention also discloses a multi-stage tandem adsorption-enhanced water-gas shift control method, applying the aforementioned multi-stage tandem adsorption-enhanced water-gas shift reaction system, such as... Figure 4 As shown, it includes the following steps: S1. Obtain the target syngas component ratio, crude syngas composition, and process parameters; S2. Calculate and set the optimal reaction parameters for each stage of the reactor and the required split ratio of the system based on the acquired data; S3. The crude syngas passes through a multi-stage series reaction module in sequence. In each stage, it undergoes a water-gas shift reaction with the added water vapor, and the generated CO2 is captured by the adsorbent. S4. The outlet gas of the last stage series reaction module enters the mixer and is mixed with the original crude syngas according to the target gas component ratio in the calculation results.

[0026] Furthermore, during the reaction process, the saturation state of the adsorbent in the reactors of each series reaction module is continuously monitored. When the adsorbent is close to saturation, the regeneration program of the corresponding reactor is started, and the process is switched to another reactor in the reaction regeneration unit to carry out the adsorption-enhanced water-gas shift reaction.

[0027] In one embodiment of the invention, a three-stage series reaction module is configured, with temperatures set at 600°C, 650°C, and 700°C, respectively. Once the reactor temperature stabilizes, valves are opened to introduce crude syngas into the system, and steam inlet valves for each stage are opened. Steam is injected proportionally according to the flow rate. The control system receives the target proportion, performs an initial optimization calculation based on the initial inlet gas composition, and outputs and executes the optimized temperature setpoints and steam quantities for each stage. When the syngas component ratio output from the reactor deviates significantly from the target, optimization adjustment is initiated. Based on real-time data, new reactor temperatures and steam input quantities for each stage are recalculated to maintain the syngas component ratio at the reactor outlet meeting the requirements.

[0028] During the reaction, when the adsorbent saturation in the reactor is detected to be greater than 90%, the reactor is prepared for switching. The unused or regenerating reactor is initialized. When the adsorbent saturation is greater than 95%, the reactor is switched through the valve. Inert purging gas is introduced into the reactor that has entered the regeneration mode. The CaCO3 that was saturated in the previous cycle in the reactor is calcined and regenerated at about 900°C. The regenerated CaO is retained in the bed, and the high concentration of CO2 released is discharged as regeneration tail gas through the valve for treatment.

[0029] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. Regarding the methods disclosed in the embodiments, since they correspond to the systems disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the system section description.

[0030] Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multi-stage series adsorption-enhanced water-gas shift reaction system, characterized in that, include: The intake monitoring module is used to acquire the composition and process parameters of the input crude syngas; The multi-stage series reaction module, connected to the intake monitoring module, includes multiple series reaction and regeneration units. The reactor of each reaction and regeneration unit is filled with catalyst and adsorbent, and each reaction and regeneration unit is equipped with an independent temperature control device. The central control module, connected to the intake monitoring module, the multi-stage series reaction module, and the mixed output module, is used to acquire real-time data of the system, calculate the optimal reaction parameters of each stage of the reaction regeneration unit, and the required split ratio of the system. The mixing output module, connected to the intake monitoring module and the multi-stage series reaction module, is used to mix the outlet gas of the multi-stage series reaction module and the raw crude syngas output with the target component ratio to produce syngas.

2. The multi-stage tandem adsorption-enhanced water-gas shift reaction system according to claim 1, characterized in that, The intake monitoring module includes an intake regulating valve, a gas composition analyzer, and a flow meter connected in sequence. The flow meter is connected to a multi-stage series reaction module. A temperature sensor and a pressure sensor are installed between the gas composition analyzer and the flow meter. The intake regulating valve is also connected to the mixing output module through a bypass regulating valve.

3. The multi-stage series adsorption-enhanced water-gas shift reaction system according to claim 1, characterized in that, In the multi-stage series reaction module, the reaction temperature, catalytic effect of the catalyst, and adsorption capacity of the adsorbent in the multiple reaction regeneration units increase progressively.

4. The multi-stage series adsorption-enhanced water-gas shift reaction system according to claim 1, characterized in that, The reaction regeneration unit includes: a first reactor and a second reactor connected in parallel, an inlet switching valve, and an outlet switching valve. The inlet switching valve is connected to the inlet pipes of the first reactor and the second reactor. A gas composition analyzer is also installed before the inlet switching valve. The outlet switching valve is connected to the outlet pipes of the first reactor and the second reactor. Both the first reactor and the second reactor are equipped with a gas inlet valve, a gas outlet valve, a water vapor inlet valve, an inert gas inlet valve, a heating device, and a temperature sensor. A flow meter is installed at all inlet valves.

5. The multi-stage tandem adsorption-enhanced water-gas shift reaction system according to claim 1, characterized in that, The central control module includes a data acquisition unit, a parameter calculation unit, and an execution scheduling unit. The data acquisition unit receives the target syngas component ratio, the composition and process parameters of the crude syngas, and the gas composition and process parameters after each stage of reaction. The parameter calculation unit calculates the optimal reaction parameters and the required split ratio of the system based on the received data. The optimal reaction parameters include the reaction temperature and water vapor addition amount for each stage. The execution scheduling unit adjusts the reaction temperature, water vapor addition amount, and real-time split ratio according to the calculation results.

6. The multi-stage series adsorption-enhanced water-gas shift reaction system according to claim 1, characterized in that, The mixing output module includes a mixing valve, a mixer, and a gas composition analyzer connected in sequence. The mixing valve is connected to the inlet monitoring module and the multi-stage series reaction module to control the mixing ratio of the outlet gas and the raw crude syngas.

7. A method for regulating water-gas shift enhanced by multi-stage series adsorption, characterized in that, The multi-stage tandem adsorption-enhanced water-gas shift reaction system according to any one of claims 1-6 includes the following steps: S1. Obtain the target syngas component ratio, crude syngas composition, and process parameters; S2. Calculate and set the optimal reaction parameters for each stage of the reactor and the required split ratio of the system based on the acquired data; S3. The crude syngas passes through a multi-stage series reaction module in sequence. In each stage, it undergoes a water-gas shift reaction with the added water vapor, and the generated CO2 is captured by the adsorbent. S4. The outlet gas of the last stage series reaction module enters the mixer and is mixed with the original crude syngas according to the target gas component ratio in the calculation results.

8. The method for regulating multi-stage series adsorption-enhanced water-gas shift according to claim 7, characterized in that, During the reaction, the saturation state of the adsorbent in the reactors of each series reaction module is continuously monitored. When the adsorbent is close to saturation, the regeneration program of the corresponding reactor is started, and the process is switched to another reactor in the reaction regeneration unit to carry out the adsorption-enhanced water-gas shift reaction.

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