A syngas preparation system and method based on cooperation of POX and DRM

Abstract

The application discloses a synthetic gas preparation system and method based on cooperation of POX and DRM, and belongs to the technical field of synthetic gas preparation. The system comprises a Fischer-Tropsch synthesis reactor, a pressure swing adsorption device, a POX module, a DRM module and a synthetic gas module. The Fischer-Tropsch synthesis reactor is used for generating aviation kerosene and tail gas by using synthetic gas. The pressure swing adsorption device is used for recovering hydrogen in the tail gas to obtain dehydrogenated tail gas. The POX module is used for performing partial oxidation treatment on the dehydrogenated tail gas to obtain intermediate gas, and the intermediate gas is delivered to the DRM module. The DRM module is used for adjusting the steam-carbon ratio of the intermediate gas, and performing steam reforming, dry reforming treatment and cooling treatment to obtain first mixed gas. The synthetic gas module is used for performing cooling and pressurizing treatment on the first mixed gas to obtain synthetic gas. The control platform is used for collecting actual process parameters of each module, and adjusting corresponding working equipment parameters based on the actual process parameters and a pre-constructed digital twin model. The system can improve the utilization rate of carbon resources in the tail gas, and precisely and stably control the hydrogen-carbon ratio of the synthetic gas.

Description

Technical Field

[0001] This invention belongs to the field of syngas preparation technology, specifically relating to a syngas preparation system and method based on the synergistic effect of POX and DRM. Background Technology

[0002] Fischer-Tropsch synthesis technology is the process of synthesizing syngas (whose main component is...) The Fischer-Tropsch synthesis is an important process for converting CO into liquid hydrocarbons and is widely used in the production of aviation kerosene. In traditional processes, the tail gas produced by the Fischer-Tropsch synthesis reaction contains large amounts of CO. , Most systems simply incinerate or simply discharge combustible and usable components as fuel gas, resulting in carbon atom utilization rates generally below 60%, leading to severe waste of carbon resources. At the control level, existing tail gas recovery and reforming systems mostly employ fixed-parameter, static open-loop control modes, capable of maintaining basic operation under steady-state conditions. They cannot adapt to dynamic disturbances such as fluctuations in feedstock composition and load changes, making them prone to problems. Problems such as accumulation, hydrogen-to-carbon ratio imbalance, steam supply and demand mismatch, and reforming temperature deviation cause the system to deviate from optimal operating conditions for a long time, resulting in a continuous decline in product yield, carbon utilization rate, and energy efficiency. Although some existing technologies have introduced partial oxidation (POX) or dry reforming (DRM) for tail gas resource utilization, most of them are applied to a single reaction unit, resulting in low tail gas carbon resource utilization rate and difficulty in accurately and stably controlling the hydrogen-to-carbon ratio of syngas.

[0003] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] To provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not intended as a general commentary, nor is it intended to identify key / important components or describe the scope of protection of these embodiments, but rather as a prelude to the detailed description that follows.

[0005] This disclosure provides a syngas preparation system and method based on the synergistic effect of POX and DRM, which can improve the utilization rate of carbon resources in tail gas and accurately and stably control the hydrogen-carbon ratio of syngas.

[0006] In some embodiments, a syngas preparation system based on the synergistic use of POX and DRM includes: a Fischer-Tropsch synthesis reactor, a pressure swing adsorption (PSA) device, a POX module, a DRM module, a syngas module, and a control platform; wherein: Fischer-Tropsch synthesis reactors are used to generate jet fuel and tail gas from syngas, and the tail gas is then transported to a pressure swing adsorption unit. Pressure swing adsorption unit is used to recover hydrogen from tail gas to obtain dehydrogenated tail gas, and then deliver the dehydrogenated tail gas to the POX module; The POX module is used to partially oxidize the dehydrogenation tail gas to obtain intermediate gas, which is then transported to the DRM module. The DRM module is used to adjust the water-to-carbon ratio of the intermediate gas and to perform steam reforming, dry reforming and cooling processes to obtain the first mixed gas, which is then delivered to the syngas module. The syngas module is used to cool and pressurize the first mixed gas to obtain syngas, and then deliver the syngas to the Fischer-Tropsch synthesis reactor. The control platform is used to collect the actual process parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module, and adjust the working equipment parameters of the pressure swing adsorption unit, POX module, DRM module, and syngas module based on the actual process parameters and the pre-constructed digital twin model.

[0007] In other embodiments, a syngas preparation method based on the synergistic effect of POX and DRM includes: The Fischer-Tropsch synthesis reactor uses syngas to generate jet fuel and exhaust gas, and the exhaust gas is then sent to a pressure swing adsorption unit. Hydrogen is recovered from the tail gas by a pressure swing adsorption device to obtain dehydrogenated tail gas, which is then sent to the POX module. The dehydrogenation tail gas is partially oxidized by the POX module to obtain intermediate gas, which is then transported to the DRM module. The water-to-carbon ratio of the intermediate gas is adjusted by the DRM module, and steam reforming, dry reforming and cooling are performed to obtain the first mixed gas, which is then delivered to the synthesis gas module. The first mixed gas is cooled and pressurized by the syngas module to obtain syngas, which is then transported to the Fischer-Tropsch synthesis reactor. The actual process parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module are collected by the control platform, and the working equipment parameters of the pressure swing adsorption unit, POX module, DRM module, and syngas module are adjusted based on the actual process parameters and the pre-constructed digital twin model.

[0008] The beneficial effects of this invention are as follows: The Fischer-Tropsch synthesis reactor utilizes syngas to generate jet fuel and tail gas. By sending the tail gas to downstream modules (pressure swing adsorption, POX module, DRM module, and syngas module) for resource recovery, efficient conversion of syngas is achieved, providing a source guarantee for the reuse of hydrocarbon resources in the tail gas. The pressure swing adsorption unit then recovers hydrogen from the tail gas to obtain dehydrogenated tail gas, which is rich in carbon resources. This avoids the resource waste caused by direct combustion of tail gas in traditional processes and effectively improves carbon resource utilization. The POX module performs partial oxidation treatment on the dehydrogenated tail gas to activate stable hydrocarbons in the dehydrogenated tail gas into syngas precursors, i.e., intermediates. The DRM module then adjusts the water-to-carbon ratio of the intermediate gas and performs steam reforming, dry reforming, and cooling treatments to obtain a first mixed gas. Through the synergistic reaction of steam reforming and dry reforming, the intermediate gas is efficiently converted into syngas precursors (i.e., the first slow mixed gas), thereby achieving deep recovery and utilization of carbon resources and significantly improving carbon atom utilization. The first mixed gas is then cooled and pressurized by the syngas module to obtain syngas, which is then transported to the Fischer-Tropsch synthesis reactor. In this way, by forming a closed-loop carbon atom system of syngas, jet fuel, tail gas, reforming, and syngas through the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module, the carbon resource utilization rate of tail gas can be effectively improved. The control platform is used to collect the actual process parameters of each module and dynamically adjust the operating equipment parameters of each module based on a pre-constructed digital twin model. This allows for real-time sensing of dynamic changes such as fluctuations in feed gas composition, thereby accurately and stably controlling the hydrogen-to-carbon ratio of the syngas.

[0009] The above general description and the description below are exemplary and illustrative only and are not intended to limit this application. Attached Figure Description

[0010] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations and drawings do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are shown as similar elements. The drawings are not to be scaled. And wherein: Figure 1 This is a schematic diagram of a syngas preparation system based on the synergistic effect of POX and DRM provided by the present invention; Figure 2 This is a schematic diagram of another syngas preparation system based on the synergistic effect of POX and DRM provided by the present invention; Figure 3 This is a flowchart of a syngas preparation method based on the synergistic effect of POX and DRM provided by the present invention. Detailed Implementation

[0011] To provide a more detailed understanding of the features and technical content of the embodiments of this disclosure, the implementation of the embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. The accompanying drawings are for illustrative purposes only and are not intended to limit the embodiments of this disclosure. In the following technical description, for ease of explanation, several details are used to provide a full understanding of the disclosed embodiments. However, one or more embodiments may still be implemented without these details. In other cases, well-known structures and devices may be simplified in their depiction to simplify the drawings.

[0012] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this disclosure described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0013] Unless otherwise stated, the term "multiple" means two or more.

[0014] In this embodiment of the disclosure, the character " / " indicates that the objects before and after it are in an "or" relationship. For example, A / B means: A or B.

[0015] The term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0016] The term "correspondence" can refer to an association or binding relationship. The correspondence between A and B means that there is an association or binding relationship between A and B.

[0017] The current Fischer-Tropsch synthesis process for jet fuel faces three major bottlenecks: 1) Resource utilization bottleneck: The large amount of CO in the reaction tail gas, Carbon resources are not effectively utilized and are usually burned as fuel gas, resulting in low carbon atom utilization (<60%).

[0018] 2) Energy and hydrogen source bottlenecks: The hydrorefining section relies on externally sourced, high-priced hydrogen, and the process steam also needs to be supplied externally. The system has high energy consumption and a fragile supply chain.

[0019] 3) Operation and control bottlenecks: Most existing tail gas recovery processes are designed as "static" processes, which cannot cope with dynamic changes such as fluctuations in the composition of the feed gas and the decay of catalyst activity. This causes the system to deviate from the optimal operating conditions in the long term, and the recovery efficiency and energy efficiency gradually decline.

[0020] To address the aforementioned issues, this invention aims to provide an intelligent chemical system with a triple closed loop of resources, energy, and information. This system not only achieves efficient recovery of hydrocarbon resources from exhaust gases and energy self-sufficiency, but also ensures that the entire system operates under optimal conditions through real-time dynamic prediction and optimization control. This maximizes carbon utilization, product yield, and economic benefits. It can be applied to the integrated design and construction of new Fischer-Tropsch synthesis jet fuel plants, the intelligent upgrading and energy-saving transformation of existing Fischer-Tropsch synthesis plants, and industrial-scale demonstrations of digital twin systems for chemical processes.

[0021] Combination Figure 1 As shown, this disclosure provides a syngas preparation system based on the synergistic use of POX and DRM, including: a Fischer-Tropsch synthesis reactor, a pressure swing adsorption device, a POX module, a DRM module, a syngas module, and a control platform; wherein: Fischer-Tropsch synthesis reactors are used to generate jet fuel and tail gas from syngas, and the tail gas is then transported to a pressure swing adsorption unit. Pressure swing adsorption unit is used to recover hydrogen from tail gas to obtain dehydrogenated tail gas, and then deliver the dehydrogenated tail gas to the POX module; The POX module is used to partially oxidize the dehydrogenation tail gas to obtain intermediate gas, which is then transported to the DRM module. The DRM module is used to adjust the water-to-carbon ratio of the intermediate gas and to perform steam reforming, dry reforming and cooling processes to obtain the first mixed gas, which is then delivered to the syngas module. The syngas module is used to cool and pressurize the first mixed gas to obtain syngas, and then deliver the syngas to the Fischer-Tropsch synthesis reactor. The control platform is used to collect the actual process parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module, and adjust the working equipment parameters of the pressure swing adsorption unit, POX module, DRM module, and syngas module based on the actual process parameters and the pre-constructed digital twin model.

[0022] This disclosure discloses a syngas production system based on the synergistic use of POX and DRM. Through a Fischer-Tropsch synthesis reactor, syngas is used to generate jet fuel and tail gas. The tail gas is then transported to downstream modules (i.e., a pressure swing adsorption (PSA) unit, a POX module, a DRM module, and a syngas module) for resource recovery, achieving efficient syngas conversion and providing a source guarantee for the reuse of hydrocarbon resources in the tail gas. Hydrogen in the tail gas is then recovered via the PSA unit to obtain dehydrogenated tail gas, which is rich in carbon resources. This avoids the resource waste caused by direct combustion of tail gas in traditional processes and effectively improves the utilization rate of carbon resources. The POX module performs partial oxidation treatment on the dehydrogenated tail gas to activate stable hydrocarbons in the dehydrogenated tail gas into syngas precursors, i.e., intermediates, through partial oxidation reactions. The intermediate gas water-to-carbon ratio is then adjusted using the DRM module, followed by steam reforming, dry reforming, and cooling to obtain the first mixed gas. Through the synergistic reaction of steam and dry reforming, the intermediate gas is efficiently converted into syngas precursor (i.e., the first slow mixed gas), thereby achieving deep recovery and utilization of carbon resources and significantly improving carbon atom utilization. The first mixed gas is then cooled and pressurized by the syngas module to obtain syngas, which is then transported to the Fischer-Tropsch synthesis reactor. In this way, by forming a closed-loop carbon atom system of syngas, jet fuel, tail gas, reforming, and syngas through the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module, the carbon atom utilization rate of tail gas carbon resources can be effectively improved. The control platform is used to collect the actual process parameters of each module and dynamically adjust the working equipment parameters of each module based on a pre-constructed digital twin model, so as to sense the dynamic changes such as fluctuations in feed gas composition in real time, thereby accurately and stably controlling the hydrogen-to-carbon ratio of the syngas.

[0023] In this embodiment, the composition (mole fraction) of the Fischer-Tropsch synthesis jet fuel tail gas (temperature: 40°C, pressure: 2.0 MPa) is as follows: , , , Other hydrocarbons: 0.09.

[0024] Preferably, a syngas preparation system based on the synergistic effect of POX and DRM further includes an isomerization hydrogenation module. The pressure swing adsorption unit delivers the recovered hydrogen to the isomerization hydrogenation module. The isomerization hydrogenation module is used to utilize hydrogen in the unsaturated hydrogenation and isomerization reaction of jet fuel.

[0025] In this way, by transporting the recovered hydrogen to the heterogeneous hydrogenation module, the module utilizes the hydrogen to participate in the unsaturated hydrogenation and isomerization reaction of jet fuel, forming a closed loop of hydrogen resources from tail gas, PSA, hydrogen, and hydrogenation section. This reduces dependence on external hydrogen and significantly lowers hydrogen procurement costs.

[0026] In this embodiment, the exhaust gas enters a pressure swing adsorption (PSA) unit to separate and recover ≥80% of the hydrogen (i.e., a hydrogen recovery rate of approximately 80%). The recovered hydrogen is then sent to the isomerization hydrogenation module to participate in the unsaturated hydrogenation and isomerization reaction of jet fuel. The remaining dehydrogenation exhaust gas (enriched) , , It then enters the downstream heat exchange process.

[0027] Online gas chromatographs (GC) and flow sensors are installed on the inlet and outlet pipes of the pressure swing adsorption unit to monitor the composition and flow rate of dehydrogenation tail gas and product hydrogen (i.e., recovered hydrogen) in real time. These data are used as key input variables and transmitted in real time to the system's intelligent control platform (i.e., digital twin).

[0028] Preferably, the POX module includes a heat exchanger and a hydrocarbon conversion reactor, the heat exchanger being connected to both the pressure swing adsorption unit and the hydrocarbon conversion reactor, and the hydrocarbon conversion reactor also being connected to the DRM module; the POX module includes: A heat exchanger is used to receive dehydrogenated tail gas and preheat the dehydrogenated tail gas to a first preset temperature, and then transport the preheated dehydrogenated tail gas to a hydrocarbon conversion reactor. The hydrocarbon conversion reactor is used to introduce oxygen and, under the influence of reactor temperature, to partially oxidize the preheated dehydrogenation tail gas to obtain intermediate gas, which is then transported to the DRM module.

[0029] In this way, the heat exchanger preheats the received dehydrogenated tail gas to a first preset temperature, and the hydrocarbon conversion reactor uses oxygen to partially oxidize the preset dehydrogenated stabilized gas, thereby removing the stable hydrocarbons (i.e., hydrocarbons) from the dehydrogenated tail gas. (etc.) are activated into highly reactive syngas precursors (i.e. and This means obtaining intermediate gas, which can then provide high-quality raw materials for downstream DRM modules.

[0030] In this embodiment, the specific process conditions of the POX module (i.e., the partial oxidation module) are as follows: the first preset temperature is 500℃. The operating pressure of the hydrocarbon conversion reactor, i.e., the POX partial oxidation reactor, is matched with the pressure of the upstream tail gas system, for example, maintained in the range of 1.8-2.2 MPa. The main reaction formula of this partial oxidation reaction is: The partial oxidation reaction occurring in the reactor is exothermic, and the reactor outlet temperature is controlled at 620℃. Under these temperature and pressure conditions, the introduced oxygen reacts with the preheated dehydrogenation tail gas, removing stable hydrocarbons (such as...) from the tail gas. ) activated into a highly active syngas precursor ( and That is, to obtain intermediate gas.

[0031] Preferably, the DRM module includes a steam reforming reactor and a steam generator, the steam reforming reactor being connected to both the hydrocarbon reforming reactor and the steam generator, and the steam generator also being connected to the syngas module; the DRM module includes: A steam reforming reactor is used to receive intermediate gas from a hydrocarbon reforming reactor and saturated steam at a first preset megapascal level through a feed steam valve to adjust the water-to-carbon ratio of the intermediate gas and obtain a second mixed gas. The second mixture is heated to a second preset temperature to perform steam reforming and dry reforming to obtain a third mixture, which is then sent to a steam generator. A steam generator is used to cool the third mixed gas to a third preset temperature to obtain saturated steam of the first mixed gas and a first preset megapascal, and to deliver the first mixed gas to the synthesis gas module; wherein the third preset temperature is less than the second preset temperature.

[0032] In this way, intermediate gas is mixed with saturated steam at a first preset megapascal (MPa) through a steam reformer to adjust the water-to-carbon ratio of the intermediate gas, resulting in a second mixed gas. The second mixed gas is then heated to a second preset temperature, where it undergoes a chemical reaction—steam reforming and dry reforming—to obtain a third mixed gas. The third mixed gas is then cooled to the third preset temperature by a steam generator to recover heat, yielding the first mixed gas and the byproduct saturated steam at the first preset MPa. This allows for the efficient conversion of intermediate gas into syngas, achieving deep recycling of carbon resources and significantly improving carbon atom utilization.

[0033] In this embodiment, the second preset temperature is 870°C, the third preset temperature is 320°C, and the first preset megapascal is 4.0 MPa.

[0034] Preferably, the second mixture is heated to a second preset temperature to perform steam reforming and dry reforming treatments on the second mixture to obtain a third mixture, and the process further includes: The second mixture is heated to a second preset temperature to perform steam reforming and dry reforming treatments on the second mixture to obtain a fourth mixture. The heat of the fourth mixture is transferred to a heat exchanger to preheat the dehydrogenation tail gas to a first preset temperature, and the fourth mixture after heat transfer is used as the third mixture; wherein, the third preset temperature < the first preset temperature < the second preset temperature.

[0035] The fourth mixed gas, obtained after steam reforming and dry reforming of the second mixed gas, has a high temperature. The heat from this fourth mixed gas is then transferred to the dehydrogenation tail gas via a heat exchanger to preheat the tail gas to a first preset temperature, achieving primary heat recovery. By recovering the waste heat from the high-temperature gas, the system's energy utilization efficiency can be significantly improved.

[0036] Preferably, the steam generator is also used for: Saturated steam at a first preset megapascal is delivered to the steam reformer through the feed steam valve.

[0037] In this way, the waste heat of the high-temperature gas after the DRM module reaction is used to produce steam, which is then transported to the steam reformer through the feed steam valve. This steam serves as the raw material for adjusting the intermediate gas-water-carbon ratio in the steam reformer, forming a closed-loop steam self-circulation system of waste heat, by-product steam, and reaction raw materials. This reduces dependence on external steam supply and lowers operating costs.

[0038] In this embodiment, the specific process conditions of the DRM module (i.e., dry reforming / steam reforming module) are as follows: the dehydrogenation tail gas exchanges heat with the high-temperature gas (i.e., the second mixed gas, whose initial temperature is 870°C) at the outlet of the methane steam reformer, raising the temperature of the dehydrogenation tail gas to 500°C.

[0039] The preheated dehydrogenation tail gas enters the hydrocarbon conversion reactor and undergoes a hydrocarbon conversion reaction at an outlet temperature of 620℃. The outlet composition (mole fraction) is as follows: , , , .

[0040] Temperature and pressure sensors are installed at the inlet and outlet of the hydrocarbon conversion reactor. A full-process mechanism model within the intelligent control platform dynamically simulates and predicts the reaction process and outlet material status within the hydrocarbon conversion reactor based on real-time composition data of the dehydrogenation tail gas from upstream. If the outlet... If the concentration deviates from the set value, the control platform will send an adjustment command in advance to the temperature controller of the hydrocarbon conversion reactor or the steam injection valve of the steam conversion reactor.

[0041] A second mixed gas is obtained by introducing 4.0 MPa saturated steam (byproduct of the steam generator) at a flow rate of 1.8 times the molar flow rate into the outlet gas (i.e., intermediate gas) of the hydrocarbon reforming reactor. The operating conditions of the steam reforming reactor are: the reaction pressure is maintained at 3.5-4.0 MPa; the second mixed gas undergoes a chemical reaction in the methane steam reforming reactor (i.e., the steam reforming reactor) at a temperature of 870°C. ) and dry reforming reaction ( The composition (mole fraction) of the outlet gas (i.e., the third mixture) is as follows: 0.37, 0.33, 0.25, :0.05.

[0042] The high-temperature gas (i.e., the second mixed gas, 870°C) at the outlet of the steam reformer preheats the feed to the hydrocarbon reformer (i.e., the dehydrogenation tail gas) to 500°C, thus achieving primary heat recovery.

[0043] After heat exchange, the gas (i.e., the third mixture, about 620°C) enters the steam generator, producing 4.0MPa high-pressure steam (i.e., the first preset megapascal saturated steam) as a byproduct. At the same time, the third mixture cools down to about 300°C (i.e., the third preset temperature) to obtain the first mixture.

[0044] The control platform calculates the water-to-carbon ratio (S / C) in real time using a model and compares it with the measured value of the steam reformer outlet temperature. If the control platform uses a digital twin model based on the recycle gas data from the Fischer-Tropsch synthesis unit to predict... There is a cumulative trend; it will automatically adjust the opening of the feed steam valve of the steam reformer, increase the water-to-carbon ratio, and thus enhance... The conversion reaction generates more effective syngas ( and Suppressing at the source The process is cyclical and cumulative. Simultaneously, the control platform dynamically optimizes the load on the steam generator to ensure that steam production meets the process requirements.

[0045] Preferably, the syngas module includes: a recovered gas cooler and a compressor, the recovered gas cooler being connected to both a steam generator and a compressor, and the compressor also being connected to a Fischer-Tropsch reactor synthesizer; the syngas module includes: A gas recovery cooler is used to receive and cool the first mixed gas delivered by the steam generator to a fourth preset temperature to obtain a fifth mixed gas, and deliver the fifth mixed gas to the compressor; wherein, the fourth preset temperature is less than the third preset temperature; A compressor is used to pressurize the fifth mixture to a second preset megapascal to obtain syngas, and to deliver the syngas to the Fischer-Tropsch synthesis reactor.

[0046] In this way, by cooling the first mixed gas delivered from the steam generator to the fourth preset temperature through a gas recovery cooler, thermal damage to the compressor from high-temperature gas can be avoided, extending the compressor's service life, and effectively reducing the water content in the syngas, thus reducing the poisoning effect of moisture on the Fischer-Tropsch synthesis catalyst. The fifth mixed gas is then pressurized to the second preset MPa by the compressor to match the inlet pressure of the Fischer-Tropsch synthesis reactor, providing stable pressure conditions for the Fischer-Tropsch synthesis reaction. Furthermore, the compressor delivers the pressurized syngas to the Fischer-Tropsch synthesis reactor, completing the carbon atom closed loop of syngas, jet fuel, tail gas, reforming, and syngas, enabling the recycling of carbon resources in the tail gas and significantly improving the overall carbon resource utilization rate.

[0047] In this embodiment, the first mixed gas is further cooled to 40–50°C (i.e., the fourth preset temperature) by a recovered gas cooler to obtain the fifth mixed gas. The fifth mixed gas is then pressurized to 2.5 MPa·g (i.e., the second preset megapascal) by a compressor to form qualified synthesis gas. / (≈1.12), the compressed syngas is transported to the inlet of the Fischer-Tropsch synthesis reactor for directional synthesis of aviation kerosene components.

[0048] The control platform receives real-time operational data (such as circulating gas composition and catalyst bed temperature) from the Fischer-Tropsch synthesis reactor. It uses this data to continuously calibrate and update its full-process model, ensuring prediction accuracy. For example, if the model predicts a decrease in the hydrogen concentration at the PSA inlet after calibration, the control platform will proactively slow down the compressor speed or adjust the adsorption sequence of the PSA unit to match the changing gas conditions. This ensures absolute stability in the purity and flow rate of the hydrogen supplied to the hydrogenation section, achieving 100% self-sufficiency in hydrogen sources.

[0049] Preferably, combined with Figure 2 As shown, this disclosure provides another syngas preparation system based on the synergistic use of POX and DRM, including a Fischer-Tropsch synthesis reactor, a pressure swing adsorption device, a POX module, a DRM module, a syngas module control platform, and an isomerization hydrogenation module; wherein, The Fischer-Tropsch synthesis reactor uses syngas to generate jet fuel and tail gas, and then sends the tail gas to a pressure swing adsorption unit. The pressure swing adsorption unit recovers hydrogen from the tail gas to obtain dehydrogenated tail gas, which is then sent to the heat exchanger in the POX module to deliver the recovered hydrogen to the heterogeneous hydrogenation module.

[0050] The isomerization hydrogenation module utilizes hydrogen to participate in the unsaturated hydrogenation and isomerization reaction of jet fuel.

[0051] In the POX module, the heat exchanger receives the dehydrogenated tail gas and preheats it to 500°C. The preheated dehydrogenated tail gas is then sent to the hydrocarbon conversion reactor. The hydrocarbon conversion reactor introduces oxygen and performs a partial oxidation reaction on the preheated dehydrogenated tail gas to obtain intermediate gas. The intermediate gas is then sent to the steam reformer in the DRM module. In the DRM module, the steam reformer receives intermediate gas and 1.8 moles of 4.0 MPa saturated steam through the feed steam valve to adjust the water-to-carbon ratio of the intermediate gas to obtain a second mixed gas. The second mixed gas is heated to 870°C for steam reforming and dry reforming to obtain a fourth mixed gas. The heat of the fourth mixed gas is transferred to a heat exchanger to preheat the dehydrogenation tail gas to 500°C. The fourth mixed gas after heat transfer is used as the third mixed gas and sent to the steam generator. The steam generator cools the third mixed gas to 320°C to obtain a first mixed gas and 4.0 MPa saturated steam. The 4.0 MPa saturated steam is sent to the steam reformer through the feed steam valve, and the first mixed gas is sent to the recovery gas cooler of the syngas module. In the syngas module, the recovered gas cooler receives and cools the first mixed gas to 40-50°C to obtain the fifth mixed gas. The fifth mixed gas is then sent to the compressor, which pressurizes the fifth mixed gas to 2.5 MPa to obtain syngas, which is then sent to the Fischer-Tropsch synthesis reactor. The control platform (not shown) collects the actual process parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module, and adjusts the equipment parameters of the pressure swing adsorption unit, POX module, DRM module, and syngas module based on the actual process parameters and the pre-constructed digital twin model.

[0052] Preferably, the control platform is specifically used for: Based on actual process parameters, the predicted outlet parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module are determined using a pre-constructed digital twin model; among which, actual process parameters include boundary state parameters and operating state parameters. The actual outlet parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module are collected. Based on the difference between the preset outlet parameters and the actual outlet parameters, the digital twin model is fine-tuned to obtain the fine-tuned digital twin model. Using a fine-tuned digital twin model, with the objective functions of maximizing jet fuel yield, maximizing carbon utilization, and minimizing total energy consumption, optimization is performed under preset constraints to determine the target operating state parameters. Based on the target operating state parameters, adjust the operating equipment parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module.

[0053] In this way, by inputting actual process parameters into the digital twin model for prediction, the predicted outlet parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module are obtained. The predicted outlet parameters are then compared with the actual outlet parameters, and the model is fine-tuned using the differences between the two, ensuring that the digital twin model remains synchronized with the physical entities, thereby effectively reducing preset errors. Using the fine-tuned digital twin model, with the objective functions of maximizing jet fuel yield, maximizing carbon utilization, and minimizing total energy consumption, optimization is performed under preset constraints to determine the target operating state parameters. These parameters are then used to adjust the operating equipment parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module. This allows for proactive adjustment of operating parameters before problems occur, preventing deviations from optimal operating conditions and enabling precise and stable control of the syngas hydrogen-to-carbon ratio.

[0054] In this embodiment, the recursive least squares (RLS) or extended Kalman filter (EKF) algorithm is used to compare the real-time data (i.e., the actual outlet parameters) with the model predictions (i.e., the predicted outlet parameters), and automatically fine-tune the key parameters in the model (such as catalyst activity α(t) and heat exchange coefficient K) so that the digital twin always keeps in sync with the physical entity and controls the long-term prediction error within 5%.

[0055] In this embodiment, the actual process parameters include the boundary state parameters and operational state parameters of the digital twin model. The boundary state parameters characterize the external boundary conditions of the system operation and the properties of upstream materials, while the operational state parameters characterize the controllable operational variables of the system. The predicted output parameters include the output parameters of each sub-module in the digital twin model.

[0056] Its boundary state parameters include those of the Fischer-Tropsch model, the pressure swing adsorption model, the POX model, the DRM model, and the syngas model; the boundary state parameters characterize the reaction conditions that are indispensable for the chemical reaction, such as reaction temperature and pressure.

[0057] Its operating state parameters include those of the pressure swing adsorption (PSA) sub-model, the POX sub-model, the DRM sub-model, and the syngas sub-model. In this embodiment, the actual process parameters include the state parameters and decision variables of the digital twin model.

[0058] The details are shown in the table below: Preferably, the digital twin model includes the Fischer-Tropsch sub-model, the pressure swing adsorption sub-model, the POX sub-model, the DRM sub-model, and the syngas sub-model.

[0059] The Fischer-Tropsch sub-model is used to simulate the Fischer-Tropsch reaction and predict parameters including exhaust gas flow rate and composition, and jet fuel production. Its input parameters include boundary state parameters, which include the current syngas feed (flow rate, ...). / The parameters include: ratio, catalyst activity (i.e., catalyst activity factor), feed syngas inlet temperature, and feed syngas inlet pressure; its operating variable parameters include Fischer-Tropsch reaction temperature; output parameters include tail gas flow rate and composition, and jet fuel production.

[0060] The pressure swing adsorption (PSA) sub-model is used to simulate the separation of hydrogen from the tail gas of the Fischer-Tropsch synthesis reaction in a PSA unit, in order to predict the process of dehydrogenation tail gas and product hydrogen (i.e., recovered hydrogen). Its input parameters include operating state parameters and boundary state parameters. The operating state parameters include the adsorption sequence (i.e., adsorption duration); the boundary state parameters include the tail gas flow rate and composition, tail gas inlet temperature, and tail gas inlet pressure output by the Fischer-Tropsch sub-model; the output parameters include the flow rate and composition of the product hydrogen and the flow rate and composition of the dehydrogenation tail gas.

[0061] The POX sub-model is used to simulate the partial oxidation reaction process in the hydrocarbon conversion reactor within the POX module, in order to predict the intermediate gas content. Concentration. Its input parameters include operating state parameters and boundary state parameters. Operating state parameters include the reactor temperature of the hydrocarbon conversion reactor; boundary state parameters include the flow rate and composition of the dehydrogenation tail gas, the inlet temperature of the dehydrogenation tail gas, the inlet pressure of the dehydrogenation tail gas, and the oxygen flow rate, etc., output by the pressure swing adsorption sub-model; output parameters include... concentration.

[0062] The DRM sub-model is used to simulate the reaction process in a steam reformer to predict... (i.e., methane) concentration. Its input parameters include operating state parameters and boundary state parameters. Its operating state parameters include the opening degree of the feed steam valve of the steam reformer and the load of the steam generator; its boundary state parameters include the methane concentration, intermediate gas inlet pressure, saturated steam flow rate, saturated steam pressure, etc. output by the POX sub-model; its output parameters are methane concentration, first mixed gas flow rate and composition.

[0063] The syngas sub-model is used to predict the syngas flow rate and composition during the cooling and pressurization of the first mixed gas in the syngas module to generate syngas. Its input parameters include operating state parameters and boundary state parameters. The operating state parameters include compressor speed; the boundary state parameters include the first mixed gas flow rate and composition, the first mixed gas inlet temperature, and the circulating cooling water temperature output by the DRM sub-model; its output parameters include the syngas flow rate and composition. In this embodiment, based on mechanistic knowledge and the first mixed gas flow rate and composition output by the DRM sub-model, flash evaporation calculations can be performed using thermodynamic phase equilibrium and the gas equation of state to determine the composition and molar flow rate of the dried syngas (i.e., the fifth mixed gas). Subsequently, based on mass conservation and the thermodynamic compression process equations, combined with the compressor speed, the gas compressibility factor and volume change are calculated using real gas equations of state (such as the PR or SRK equations) to accurately output the syngas flow rate and composition that meet the feed requirements for Fischer-Tropsch synthesis.

[0064] In this embodiment, when constructing each sub-model, a mechanistic sub-model can be built based on the corresponding mechanistic knowledge to achieve prediction. Alternatively, a black-box model (such as a long short-term memory network model) can be built based on historical operating data and machine learning algorithms to achieve prediction. No limitation is imposed here.

[0065] The objective function, expressed using a multi-objective weighted method, is as follows: in, Jet kerosene yield (jet fuel production / syngas production output from the Fischer-Tropsch synthesis submodel), unit: kg jet kerosene / kg syngas; Carbon utilization rate = (Number of carbon atoms converted into jet fuel / Total number of carbon atoms entering the system, which is determined by the composition and flow rate of the syngas) × 100%; Total system energy consumption (including PSA, POX, DRM, and compressor energy consumption), unit: kJ / h.

[0066] In this embodiment, , , These are weighting coefficients, adjusted according to production needs, such as... =0.4, =0.4, =0.2.

[0067] The operating parameters include: 1) Pressure Swing Adsorption Unit: Adsorption time t_PSA, ranging from 10 to 20 min; 2) POX Module: Reactor temperature T_POX, ranging from 900 to 1100°C; 3) DRM Module: Feed steam valve opening V_steam, ranging from 20% to 100%; Steam generator load Q_steam, ranging from 1000 to 5000 kW; 4) Syngas Module: Compressor speed N_comp, ranging from 1000 to 3000 rpm.

[0068] The preset constraints include: (1) the bed temperature of the steam reformer is <880°C (to prevent catalyst sintering); (2) the compressor speed is in the anti-surge range; (3) the PSA hydrogen recovery rate is >80%; (4) the synthesis gas... / CO molar ratio = 2.0-2.2.

[0069] The optimization algorithm can be solved using the NSGA-II multi-objective genetic algorithm or the sequence quadratic programming (SQP) algorithm, and no specific limitation is made here.

[0070] In this way, by maximizing both jet fuel yield and carbon utilization, it is possible to balance both product output and resource efficiency.

[0071] In this embodiment, the equipment parameters of the pressure swing adsorption device are the adsorption timing of the pressure swing adsorption device; The equipment parameter for the POX module is the temperature of the hydrocarbon conversion reactor; The equipment parameters of the DRM module include the opening degree of the feed steam valve of the steam reformer and the load of the steam generator; The equipment parameter for the syngas module is the compressor speed.

[0072] The preset constraints include: steam reformer bed temperature <880°C (to prevent catalyst sintering), compressor speed within the anti-surge range, and PSA (pressure swing adsorption) hydrogen recovery rate >80%.

[0073] Preferably, combined with Figure 3 As shown in the embodiments of this disclosure, a method for preparing syngas based on the synergistic effect of POX and DRM is provided, including: Step S101: syngas is used to generate jet fuel and tail gas through a Fischer-Tropsch synthesis reactor, and the tail gas is then transported to a pressure swing adsorption unit. Step S102: Hydrogen is recovered from the tail gas through a pressure swing adsorption device to obtain dehydrogenated tail gas, and the dehydrogenated tail gas is delivered to the POX module. Step S103: Partial oxidation treatment of the dehydrogenation tail gas is performed through the POX module to obtain intermediate gas, and the intermediate gas is then transported to the DRM module. Step S104: Adjust the water-to-carbon ratio of the intermediate gas through the DRM module, and perform steam reforming, dry reforming and cooling treatments to obtain the first mixed gas, which is then delivered to the synthesis gas module. Step S105: The first mixed gas is cooled and pressurized through the syngas module to obtain syngas, and the syngas is then transported to the Fischer-Tropsch synthesis reactor. Step S106: Collect the actual process parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module through the control platform, and adjust the working equipment parameters of the pressure swing adsorption unit, POX module, DRM module, and syngas module based on the actual process parameters and the pre-constructed digital twin model.

[0074] This disclosure discloses a syngas preparation method based on the synergistic use of POX and DRM. The method utilizes syngas in a Fischer-Tropsch reactor to generate jet fuel and tail gas. The tail gas is then transported to downstream modules (i.e., a pressure swing adsorption (PSA) unit, a POX module, a DRM module, and a syngas module) for resource recovery, achieving efficient syngas conversion and providing a source guarantee for the reuse of hydrocarbon resources in the tail gas. Hydrogen in the tail gas is then recovered via the PSA unit to obtain dehydrogenated tail gas, which is rich in carbon resources. This avoids the resource waste caused by direct combustion of tail gas in traditional processes and effectively improves carbon resource utilization. The POX module performs partial oxidation treatment on the dehydrogenated tail gas to activate stable hydrocarbons in the dehydrogenated tail gas into syngas precursors, i.e., intermediates, through partial oxidation reactions. The intermediate gas water-to-carbon ratio is then adjusted using the DRM module, followed by steam reforming, dry reforming, and cooling to obtain the first mixed gas. Through the synergistic reaction of steam and dry reforming, the intermediate gas is efficiently converted into syngas precursor (i.e., the first slow mixed gas), thereby achieving deep recovery and utilization of carbon resources and significantly improving carbon atom utilization. The first mixed gas is then cooled and pressurized by the syngas module to obtain syngas, which is then transported to the Fischer-Tropsch synthesis reactor. In this way, by forming a closed-loop carbon atom system of syngas, jet fuel, tail gas, reforming, and syngas through the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module, the carbon atom utilization rate of tail gas carbon resources can be effectively improved. The control platform is used to collect the actual process parameters of each module and dynamically adjust the working equipment parameters of each module based on a pre-constructed digital twin model, so as to sense the dynamic changes such as fluctuations in feed gas composition in real time, thereby accurately and stably controlling the hydrogen-to-carbon ratio of the syngas.

[0075] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A syngas preparation system based on the synergistic effect of POX and DRM, comprising: The system comprises a Fischer-Tropsch synthesis reactor, a pressure swing adsorption unit, a POX module, a DRM module, a syngas module, and a control platform; among which: Fischer-Tropsch synthesis reactors are used to generate jet fuel and tail gas from syngas, and the tail gas is then transported to a pressure swing adsorption unit. Pressure swing adsorption unit is used to recover hydrogen from tail gas to obtain dehydrogenated tail gas, and then deliver the dehydrogenated tail gas to the POX module; The POX module is used to partially oxidize the dehydrogenation tail gas to obtain intermediate gas, which is then transported to the DRM module. The DRM module is used to adjust the water-to-carbon ratio of the intermediate gas and to perform steam reforming, dry reforming and cooling processes to obtain the first mixed gas, which is then delivered to the syngas module. The syngas module is used to cool and pressurize the first mixed gas to obtain syngas, and then deliver the syngas to the Fischer-Tropsch synthesis reactor. The control platform is used to collect the actual process parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module, and adjust the working equipment parameters of the pressure swing adsorption unit, POX module, DRM module, and syngas module based on the actual process parameters and the pre-constructed digital twin model.

2. The system according to claim 1, characterized in that, The POX module includes a heat exchanger and a hydrocarbon conversion reactor. The heat exchanger is connected to the pressure swing adsorption unit and the hydrocarbon conversion reactor, respectively, and the hydrocarbon conversion reactor is also connected to the DRM module. The POX module includes: A heat exchanger is used to receive dehydrogenated tail gas and preheat the dehydrogenated tail gas to a first preset temperature, and then transport the preheated dehydrogenated tail gas to a hydrocarbon conversion reactor. The hydrocarbon conversion reactor is used to introduce oxygen and, under the influence of reactor temperature, to partially oxidize the preheated dehydrogenation tail gas to obtain intermediate gas, which is then transported to the DRM module.

3. The system according to claim 2, characterized in that, The DRM module includes a steam reforming reactor and a steam generator. The steam reforming reactor is connected to both the hydrocarbon reforming reactor and the steam generator, and the steam generator is also connected to the syngas module. The DRM module includes: A steam reforming reactor is used to receive intermediate gas from a hydrocarbon reforming reactor and saturated steam at a first preset megapascal level through a feed steam valve to adjust the water-to-carbon ratio of the intermediate gas and obtain a second mixed gas. The second mixture is heated to a second preset temperature to perform steam reforming and dry reforming to obtain a third mixture, which is then sent to a steam generator. A steam generator is used to cool the third mixed gas to a third preset temperature to obtain saturated steam of the first mixed gas and a first preset megapascal, and to deliver the first mixed gas to the synthesis gas module; wherein the third preset temperature is less than the second preset temperature.

4. The system according to claim 3, characterized in that, Heating the second mixture to a second preset temperature to perform steam reforming and dry reforming treatments on the second mixture to obtain a third mixture, further comprising: The second mixture is heated to a second preset temperature to perform steam reforming and dry reforming treatments on the second mixture to obtain a fourth mixture. The heat of the fourth mixture is transferred to a heat exchanger to preheat the dehydrogenation tail gas to a first preset temperature, and the fourth mixture after heat transfer is used as the third mixture; wherein, the third preset temperature < the first preset temperature < the second preset temperature.

5. The system according to claim 3, characterized in that, Steam generators are also used for: Saturated steam at a first preset megapascal is delivered to the steam reformer through the feed steam valve.

6. The system according to claim 3, characterized in that, The syngas module includes: a recovered gas cooler and a compressor, the recovered gas cooler being connected to both a steam generator and a compressor, and the compressor also being connected to the Fischer-Tropsch reactor synthesizer; the syngas module includes: A gas recovery cooler is used to receive and cool the first mixed gas delivered by the steam generator to a fourth preset temperature to obtain a fifth mixed gas, and deliver the fifth mixed gas to the compressor; wherein, the fourth preset temperature is less than the third preset temperature; A compressor is used to pressurize the fifth mixture to a second preset megapascal to obtain syngas, and to deliver the syngas to the Fischer-Tropsch synthesis reactor.

7. The system according to any one of claims 1 to 6, characterized in that, The control platform is specifically used for: Based on actual process parameters, the predicted outlet parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module are determined using a pre-constructed digital twin model; among which, actual process parameters include boundary state parameters and operating state parameters. The actual outlet parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module are collected. Based on the difference between the preset outlet parameters and the actual outlet parameters, the digital twin model is fine-tuned to obtain the fine-tuned digital twin model. Using a fine-tuned digital twin model, with the objective functions of maximizing jet fuel yield, maximizing carbon utilization, and minimizing total energy consumption, optimization is performed under preset constraints to determine the target operating state parameters. Based on the target operating state parameters, adjust the operating equipment parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module.

8. A method for preparing syngas based on the synergistic effect of POX and DRM, characterized in that, include: The Fischer-Tropsch synthesis reactor uses syngas to generate jet fuel and exhaust gas, and the exhaust gas is then sent to a pressure swing adsorption unit. Hydrogen is recovered from the tail gas by a pressure swing adsorption device to obtain dehydrogenated tail gas, which is then sent to the POX module. The dehydrogenation tail gas is partially oxidized by the POX module to obtain intermediate gas, which is then transported to the DRM module. The water-to-carbon ratio of the intermediate gas is adjusted by the DRM module, and steam reforming, dry reforming and cooling are performed to obtain the first mixed gas, which is then delivered to the synthesis gas module. The first mixed gas is cooled and pressurized by the syngas module to obtain syngas, which is then transported to the Fischer-Tropsch synthesis reactor. The actual process parameters of the Fischer-Tropsch synthesis reactor, pressure swing adsorption unit, POX module, DRM module, and syngas module are collected by the control platform, and the working equipment parameters of the pressure swing adsorption unit, POX module, DRM module, and syngas module are adjusted based on the actual process parameters and the pre-constructed digital twin model.

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