Method and system for combined power generation of h2s-co2 catalytic synthesis gas and activated carbon activation tail gas

Abstract

The application discloses a kind of H2S-CO2 catalytic synthesis gas and activated carbon activation tail gas combined power generation method and system, belong to industrial synthesis gas and tail gas resource utilization technical field, using hierarchical stable pressure buffer convergence homogenization, deep desulfurization and deoxidation, variable frequency pressurization adaptation, gas turbine stable power generation and waste heat deep reuse, realize the efficient coupling of two gas sources, deep upgrading, precise adaptation gas turbine inlet requirement.The utilization rate of the synthesis gas of the present application is improved to more than 99%, the power generation efficiency is improved by more than 15%, which solves the core defects of poor gas source adaptability, low power generation efficiency, short equipment life and unstable operation in the prior art, and can be widely used in the energy utilization and distributed energy supply of industrial hydrogen-containing and carbon-containing tail gas.

Description

Technical Field

[0001] This invention belongs to the field of industrial syngas and tail gas resource utilization technology, specifically relating to a method and system for combined power generation of H2S-CO2 catalytic syngas and activated carbon activated tail gas. Background Technology

[0002] The H2S and CO2 co-catalytic conversion technology can convert two acidic pollutants—associated gas from oil fields and tail gas from coal-based activated carbon production—into industrial sulfur and catalytic synthesis gas (i.e., H2S-CO2 catalytic synthesis gas). This catalytic synthesis gas contains 30–40 vol% CO and 45–55 vol% H2, making it a high-quality clean fuel. Simultaneously, the activation process in coal-based activated carbon production generates a large amount of tail gas containing 15–30 vol% CO and 10–20 vol% H2, which also possesses significant energy utilization value. However, in practical industrial applications, the energy utilization of these two gas sources faces the following core and unavoidable industry challenges:

[0003] (1) The efficiency of using it alone is extremely low and it cannot be stably adapted to gas turbine power generation: H2S-CO2 catalytic synthesis gas has the characteristics of small gas volume (1000-2000Nm³ / h), low pressure and large flow fluctuation. When it enters the gas turbine alone, it cannot burn stably and is prone to flameout and tripping failures. The average number of shutdowns per month can reach more than 12, and it cannot achieve continuous and stable power generation. Activated carbon activated tail gas has the characteristics of large gas volume (3000-8000Nm³ / h), high inert gas content, low calorific value and excessive sulfur and oxygen content. Its power generation efficiency alone is only 22%, which is more than 16 percentage points lower than the rated efficiency of the gas turbine, resulting in serious energy waste.

[0004] (2) No suitable upgrading process to meet the gas turbine intake requirements: Gas turbines have strict requirements for intake gas quality, with total sulfur content ≤20mg / Nm³, oxygen content ≤0.5vol%, and pressure fluctuation ≤±2%. Existing syngas upgrading technologies are mostly designed for large-scale and stable gas sources in coal chemical industry, and cannot be adapted to the specific operating conditions of wide fluctuation and low sulfur requirements after mixing two industrial tail gases. Excessive sulfur and oxygen content will cause corrosion, carbon deposits, and ablation of gas turbine blades, shortening the service life of equipment from 10 years to less than 3 years, resulting in extremely high maintenance costs.

[0005] (3) Lack of pressure and combustion stabilization design makes it unsuitable for wide operating conditions in industrial settings: During the start-up, shutdown, and operation adjustment of the activated carbon activation furnace, the flow rate and composition of the exhaust gas can fluctuate by up to ±30%. The H2S-CO2 catalytic system will also experience flow fluctuations with changes in the feed gas. The fluctuation amplitude is further amplified after the two gas sources are superimposed. The existing technology lacks a targeted buffering and homogenization design, resulting in extremely large fluctuations in the gas pressure and calorific value after mixing. This cannot meet the stable intake requirements of the gas turbine, leading to large fluctuations in power generation load, which cannot adapt to the power demand of factory production and may even impact the power grid.

[0006] (4) No closed-loop energy design and extremely low energy utilization rate: Existing technology only realizes simple combustion power generation, without coupling the waste heat of power generation with the front-end desulfurization, decarbonization and catalytic conversion process, and cannot realize the system self-heating. It requires a large amount of steam to be consumed, and the steam cost accounts for more than 40% of the operating cost. The energy utilization rate is less than 60%, which is far below the advanced level in the industry.

[0007] (5) No safety interlock protection, high risk of flammability and explosion: CO and H2 in syngas are Class A flammable and explosive gases. Existing technology lacks a dedicated safety interlock design for the mixing of the two industrial tail gases, which poses multiple safety risks such as overpressure, leakage, explosion, and gas turbine detonation, and cannot meet the safety production requirements of chemical industrial parks and factories.

[0008] Therefore, this invention designs a method and system for the combined power generation of H2S-CO2 catalytic synthesis gas and activated carbon-activated tail gas by improving the quality of two gas sources, merging and stabilizing them, and implementing intelligent control. Summary of the Invention

[0009] The purpose of this invention is to provide a method and system for combined power generation of H2S-CO2 catalytic synthesis gas and activated carbon activated tail gas, aiming to solve the following technical problems: (1) The efficiency of using the two gas sources alone is low, and they cannot be stably adapted to gas turbine power generation, and are prone to flameout and tripping; (2) The existing upgrading process cannot meet the stringent gas turbine intake requirements, and the sulfur and oxygen levels of the two gas sources are too high, which can easily damage the gas turbine equipment; (3) The gas source fluctuates over a wide range, and the gas after mixing is unstable, making it impossible to achieve continuous and stable power generation; (4) The existing technology has a low comprehensive energy utilization rate, no waste heat closed-loop design, and high operating costs; (5) The existing device has imperfect safety interlocks and high risk of flammability and explosion.

[0010] To achieve the above objectives, the first aspect of the present invention provides a method for combined power generation of H2S-CO2 catalytic synthesis gas and activated carbon-activated tail gas, comprising the following steps:

[0011] S1 Syngas Combination: Catalytic synthesis gas and activated carbon plant pretreatment gas undergo primary pressure stabilization treatment to control pressure fluctuations to ≤±5%. They are then combined at a volume ratio of 1:(3~4) and undergo secondary pressure stabilization treatment to achieve homogenization of pressure, temperature, and composition. The mixed gas temperature is controlled at 40±5℃, pressure fluctuation ≤±3%, CO+H2 volume concentration at 35~55vol% (preferably 50~55vol%), and lower heating value ≥3000kcal / Nm³. The catalytic synthesis gas includes CO 30~40vol%, H2 45~55vol%, and H2S ≤20mg / Nm³. 3 H2O ≤ 100ppm, N2 balance, flow rate 1000~2000Nm 3 / h; Pre-treatment gas in activated carbon plants includes CO 15-30 vol%, H2 10-20 vol%, CO2 8-15 vol%, H2S 0.1-0.5 vol%, and tar ≤10 mg / Nm³. 3 N2 surplus, flow rate 3000~8000Nm 3 / h.

[0012] S2 Syngas Upgrading and Purification: The stabilized syngas undergoes desulfurization, deoxygenation, and filtration sequentially to obtain a total sulfur content ≤20mg / Nm³. 3 High-quality syngas with oxygen content ≤0.5 vol%, dust ≤1 mg / Nm³, water dew point ≤-10℃, and pressure fluctuation ≤±3%.

[0013] S3 Variable frequency boosting and stabilization and gas turbine power generation: The syngas obtained in step S2 is boosted to 0.4-0.6 MPa by a variable frequency screw compressor, and after being stabilized by a pressure stabilizing tank, it enters a low-NOx gas turbine generator set to generate electricity.

[0014] S4 waste heat closed-loop reuse: recovers the heat from the high-temperature flue gas discharged from the gas turbine and sends it to a shell-and-tube waste heat boiler to produce saturated steam, which is then reused.

[0015] A second aspect of this invention provides a combined H2S-CO2 catalytic syngas and activated carbon-activated tail gas power generation system, comprising a syngas collection unit, a syngas upgrading and purification unit, a variable frequency boosting and stabilizing unit with a gas turbine power generation unit, and a waste heat recovery unit. The syngas collection unit includes a first buffer pressure stabilizing tank, a second buffer pressure stabilizing tank, and a mixing buffer pressure stabilizing tank. The syngas upgrading and purification unit includes a fine desulfurization tower, a catalytic deoxygenation tower, and a 1μm... The precision filter, variable frequency booster and pressure stabilization unit, and gas turbine power generation unit include a variable frequency screw compressor, a pressure stabilizing tank, and a low-NOx gas turbine generator set connected in sequence. Catalytic synthesis gas and activated carbon plant pretreatment gas undergo pressure stabilization treatment in a first buffer pressure stabilizing tank and a second buffer pressure stabilizing tank, respectively. The outlet pressure fluctuation of the first and second buffer pressure stabilizing tanks is ≤±5%. The inlet of the mixing buffer pressure stabilizing tank is connected to the outlets of the first and second buffer pressure stabilizing tanks, respectively. The temperature of the mixed gas is controlled at 40±5℃, the pressure fluctuation is ≤±3%, the CO+H2 volume concentration is 35~55%, and the lower heating value is ≥3000kcal / Nm³. 3 The mixing buffer pressure stabilizing tank, fine desulfurization tower, catalytic deoxygenation tower, and 1μm precision filter are connected in sequence. After desulfurization, deoxygenation, and filtration, high-quality syngas is obtained, with a total sulfur content ≤20mg / Nm³. 3 Oxygen content ≤ 0.5 vol%, dust ≤ 1 mg / Nm³ 3 The water dew point is ≤-10℃. High-quality syngas is pressurized to 0.4~0.6MPa by a variable frequency screw compressor, and after being stabilized by a pressure stabilizing tank, it enters the low-NOx gas turbine generator set to generate electricity. The waste heat recovery unit is used to convert the heat in the high-temperature flue gas generated by the power generation unit into steam.

[0016] The mixing buffer pressure stabilizing tank has a vertical structure. Inside the tank, from bottom to top, there are multiple layers of baffle-type airflow distributors, anti-vortex baffles, and static mixing elements. The mixing zone is located above the static mixing elements.

[0017] The multi-layer baffle airflow distributor shown is a three-layer baffle airflow distributor.

[0018] The fine desulfurization tower is filled with modified coal-based activated carbon fine desulfurization agent, with a space velocity of 1000-2000 h⁻¹. -1 Desulfurization accuracy ≤0.1ppm, sulfur penetration capacity ≥20%.

[0019] The catalytic deoxygenation tower is filled with 0.5 wt% Pd / Al2O3 deoxygenation catalyst, and the reaction temperature is 80–120℃ with a space velocity of 500–1000 h⁻¹. -1 Deoxygenation accuracy ≤ 0.1 vol.

[0020] The gas turbine power generation unit includes a variable frequency screw compressor, a pressure stabilizing tank, a low-NOx gas turbine generator set, a grid connection cabinet, and a low-voltage distribution cabinet connected in sequence, which are used for syngas power generation and power supply for plant production.

[0021] Furthermore, the waste heat recovery unit includes a shell-and-tube waste heat boiler, a steam network, and a steam distribution cylinder. The flue gas side of the waste heat boiler is connected to the exhaust port of the gas turbine, and the steam outlet distributes the generated steam to the required equipment through the steam distribution cylinder.

[0022] Furthermore, the H2S-CO2 mixed gas synergistic resource utilization treatment system also includes a DCS intelligent control unit. The DCS intelligent control unit includes a combustible gas leakage interlock module, a gas source flow interlock module, a pressure interlock module, a component exceeding standard interlock module, a gas turbine fault interlock module, and an emergency shutdown interlock module. The combustible gas leakage interlock module is used to detect the combustible gas content in equipment and pipelines in real time and promptly identify the equipment and location of combustible gas leaks. The gas source flow interlock module is used to monitor and control the inlet and outlet gas flow of each unit in real time. The pressure interlock module is used to monitor the outlet pressure fluctuations of each unit in real time. The component exceeding standard interlock module is used to detect the component content at the outlet of the syngas upgrading and purification unit in real time. The gas turbine fault interlock module is used to promptly detect gas turbine faults. The combustible gas leakage interlock module, gas source flow interlock module, pressure interlock module, component exceeding standard interlock module, and gas turbine fault interlock module are all connected to the emergency shutdown interlock module to perform emergency shutdown control based on the detection status.

[0023] The variable frequency screw compressor is equipped with a PLC variable frequency control system, which is interlocked with the gas turbine's intake pressure, unit load, and speed. The response time is ≤0.5s, and the intake pressure fluctuation is controlled to be ≤±2%.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] (1) For the first time, the efficient coupling of two gas sources is achieved, and the power generation efficiency is greatly improved: This invention converts two low-grade industrial tail gases into high-quality gas turbine fuel, and the syngas utilization rate is increased from 60% in the existing technology to more than 99%, the power generation efficiency is increased by more than 15 percentage points, and the annual power generation is increased by 1.68 million kWh / 1.2MW installed capacity, which completely solves the pain points of low efficiency and easy tripping when used alone.

[0026] (2) Perfectly adapted to the gas turbine intake requirements, significantly extending the service life of the equipment: The deep upgrading process can control the total sulfur content to within 20mg / Nm³ and the oxygen content to within 0.5vol%, fully meeting the gas turbine intake standards, completely solving the pain points of blade corrosion, carbon deposits, and ablation, extending the service life of the gas turbine from 3 years to more than 10 years, and reducing equipment maintenance costs by more than 70%.

[0027] (3) Extremely strong adaptability to wide operating conditions and leading stability in the industry: Through the three-level stability control design of graded pressure stabilization, mixing homogenization and frequency conversion adaptation, it can adapt to extreme fluctuations of ±30% of gas source flow. The generator set has no shutdown or tripping faults and the continuous operating time is ≥7200h / year, which is more than 80% higher than the existing technology.

[0028] (4) The comprehensive energy utilization rate is greatly improved and the operating cost is significantly reduced: the waste heat closed-loop recycling design reduces or even eliminates the need to purchase steam from outside, and the comprehensive energy utilization rate is increased from 60% of the existing technology to more than 85%, and the annual operating cost is reduced by more than 40%.

[0029] (5) The safety interlock is perfect and the safety production level is maximized: The safety interlock design has an interlock response time of ≤1s, which can realize the full-process fully automatic closed-loop control, completely eliminating the safety risks of toxic gas leakage, combustible gas explosion and gas turbine detonation, and fully meeting the safety production requirements of chemical industrial parks and factories.

[0030] (6) Low investment cost and high promotion value: This process can be directly matched with existing H2S-CO2 catalytic devices and activated carbon production lines without the need for large-scale modification of existing devices. The modification cost is low and it can be quickly promoted to multiple industries such as oil and gas fields, coal chemical industry, and activated carbon production. It is of great significance to the energy utilization of industrial waste gas and the development of distributed energy. Attached Figure Description

[0031] Figure 1 is a schematic diagram of the structure of the H2S-CO2 catalytic synthesis gas and activated carbon activated tail gas combined power generation method of the present invention.

[0032] Figure 2 is a schematic diagram of the hybrid buffer pressure stabilizing tank structure involved in this invention. Detailed Implementation

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

[0034] A method for combined power generation using H2S-CO2 catalytic synthesis gas and activated carbon-activated tail gas includes the following steps:

[0035] S1 Syngas Combination: Catalytic synthesis gas and pretreated gas from the activated carbon plant undergo primary pressure stabilization treatment to control pressure fluctuations to ≤±5%. Then, they are combined at a volume ratio of 1:(3~4) and undergo secondary pressure stabilization treatment to achieve homogenization of pressure, temperature, and composition. The temperature of the mixed gas is controlled at 40±5℃, pressure fluctuations are ≤±3%, CO+H2 volume concentration is 35~55vol%, and lower heating value is ≥3000kcal / Nm³.

[0036] In step S1 of this invention, either the associated gas from the oilfield or the tail gas from the production of coal-based activated carbon is sequentially subjected to raw material pretreatment, selective adsorption and regeneration of H2S, adsorption and regeneration of CO2, and non-thermal plasma synergistic catalytic conversion into industrial sulfur and catalytic synthesis gas (i.e., H2S-CO2 catalytic synthesis gas). The catalytic synthesis gas includes CO 30-40 vol%, H2 45-55 vol%, and H2S ≤ 20 mg / Nm³. 3 H2O ≤ 100ppm, N2 balance, flow rate 1000~2000Nm 3 / h.

[0037] In step S1 of this invention, the high-temperature tail gas containing CO and H2 generated in the coal-based activated carbon activation section is collected in a closed system and pretreated by cyclone dust removal, electrostatic precipitator for tar, and molecular sieve dehydration to obtain the pretreated gas for the activated carbon plant. The high-temperature tail gas of the coal-based activated carbon includes: CO 15-30 vol%, H2 10-20 vol%, CO2 8-15 vol%, H2S 0.1-0.5 vol%, and tar 500-2000 mg / Nm³. 3 N2 balance, temperature 80–150℃, flow rate 3000–8000 Nm³ 3 The pretreated gas obtained from the activated carbon plant after treatment includes CO 15-30 vol%, H2 10-20 vol%, CO2 8-15 vol%, H2S 0.1-0.5 vol%, and tar ≤10 mg / Nm³. 3 N2 surplus, flow rate 3000~8000Nm 3 / h.

[0038] To address the fluctuation characteristics of the two gas sources, a primary pressure stabilization stage is set up to control the pressure fluctuation of a single gas source within ±5%, eliminating the superposition effect of fluctuations at the source. After stabilization, the two gas sources undergo a secondary pressure stabilization process simultaneously. Through a multi-layer distributor and mixing element, the pressure, temperature, and composition are completely homogenized, and the pressure fluctuation after mixing is controlled within ±3%, thus completely solving the problem of unstable gas turbine operation caused by gas source fluctuations.

[0039] S2 Syngas Upgrading and Purification: The stabilized syngas undergoes desulfurization, deoxygenation, and filtration sequentially to obtain a total sulfur content ≤20mg / Nm³. 3 High-quality syngas with oxygen content ≤0.5 vol%, dust ≤1 mg / Nm³, water dew point ≤-10℃, and pressure fluctuation ≤±3%.

[0040] In step S2 of this invention, desulfurization is performed using modified coal-based activated carbon fine desulfurizer, with a space velocity of 1000–2000 h⁻¹. -1 Desulfurization accuracy ≤0.1ppm, sulfur penetration capacity ≥20%.

[0041] In step S2 of this invention, deoxidation is performed using a 0.5 wt% Pd / Al2O3 deoxidation catalyst at a reaction temperature of 80–120 °C and a space velocity of 500–1000 h⁻¹. -1 Deoxygenation accuracy ≤ 0.1 vol.

[0042] In step S2 of this invention, filtration is performed using 1μm precision filtration.

[0043] To address the stringent requirements of gas turbines for sulfur and oxygen content, a proprietary upgrading process of "modified coal-based activated carbon fine desulfurization + palladium-based catalytic deoxygenation" was developed. The total sulfur removal accuracy is ≤0.1ppm, and the oxygen content is controlled within 0.5vol%, fully meeting the gas turbine intake requirements. This completely solves the pain points of gas turbine blade corrosion and carbon deposits, extending the equipment service life by more than 3 times.

[0044] S3 Variable frequency boosting and stabilization and gas turbine power generation: The syngas obtained in step S2 is boosted to 0.4-0.6 MPa by a variable frequency screw compressor, and after being stabilized by a pressure stabilizing tank, it enters a low-NOx gas turbine generator set to generate electricity.

[0045] During the process, the variable frequency screw compressor variable frequency system is interlocked with the gas turbine intake pressure and unit load to control the intake pressure fluctuation ≤±2% and the generator set load adjustment range 30%~110%, perfectly adapting to the ±30% fluctuation of gas source flow and composition.

[0046] The low-NOx gas turbine is a distributed gas turbine, adapted to low-calorific-value syngas, with NOx emissions ≤50mg / Nm³, and power generation efficiency ≥38%, which is more than 16 percentage points higher than that of traditional steam turbines.

[0047] This process can compensate for the small gas volume (1000-2000 Nm³) of single catalytic synthesis gas. 3 The gas turbine suffers from drawbacks such as unstable combustion due to low pressure and large flow fluctuations, leading to flameout, turbine shutdown, and other malfunctions. Catalytic synthesis gas is combined with the primary combustible components of activated carbon for upgrading and then used in gas turbine power generation.

[0048] S4 waste heat closed-loop reuse: recovers the heat from the high-temperature flue gas discharged from the gas turbine and sends it to a shell-and-tube waste heat boiler to produce saturated steam, which is then used in catalytic synthesis gas processes, activated carbon plants, etc.

[0049] like Figure 1 As shown, an H2S-CO2 catalytic syngas and activated carbon activated tail gas combined power generation system includes a syngas collection unit 1, a syngas upgrading and purification unit 2, a variable frequency boosting and stabilizing gas turbine power generation unit 3, and a waste heat recovery unit 4. The syngas collection unit 1 includes a first buffer pressure stabilizing tank 101, a second buffer pressure stabilizing tank 102, and a mixing buffer pressure stabilizing tank 103. The syngas upgrading and purification unit 2 includes a fine desulfurization tower 201, a catalytic deoxygenation tower 202, and a 1μm... The precision filter 203, the variable frequency boosting and stabilizing unit 3 and the gas turbine generator unit 3 include a variable frequency screw compressor 301, a pressure stabilizing tank 302, and a low-NOx gas turbine generator set 303 connected in sequence. The catalytic synthesis gas and the pre-treated gas from the activated carbon plant are respectively pressure-stabilized by the first buffer pressure stabilizing tank 101 and the second buffer pressure stabilizing tank 102. The outlet pressure fluctuation of the first buffer pressure stabilizing tank 101 and the second buffer pressure stabilizing tank 102 is ≤±5%. The inlet of the mixing buffer pressure stabilizing tank 103 is connected to the outlet of the first buffer pressure stabilizing tank 101 and the second buffer pressure stabilizing tank 102. The temperature of the mixed gas is controlled at 40±5℃, the pressure fluctuation is ≤±3%, the CO+H2 volume concentration is 35~55 vol%, and the lower heating value is ≥3000kcal / Nm³. 3 The mixing buffer pressure stabilizing tank 103, the fine desulfurization tower 201, the catalytic deoxygenation tower 202, and the 1μm precision filter 203 are connected in sequence. After desulfurization, deoxygenation, and filtration, high-quality syngas is obtained, with a total sulfur content ≤20mg / Nm³. 3 Oxygen content ≤ 0.5 vol%, dust ≤ 1 mg / Nm³ 3 The water dew point is ≤-10℃. High-quality syngas is pressurized to 0.4~0.6MPa by a variable frequency screw compressor. After being stabilized by a pressure stabilizing tank, it enters the low-NOx gas turbine generator set to generate electricity. Waste heat recovery unit 4 is used to convert the heat in the high-temperature flue gas generated by the power generation unit into steam.

[0050] As one implementation method, such as Figure 2As shown, the mixing buffer pressure stabilizing tank 103 has a vertical structure. Inside the tank, from bottom to top, are arranged a multi-layer baffle-type airflow distributor B01 (preferably a three-layer baffle-type airflow distributor), an anti-vortex baffle B02, and a static mixing element B03. Above the static mixing element B03 is a mixing zone B04. The mixing buffer pressure stabilizing tank 103 is equipped with a pressure transmitter, a temperature transmitter, an infrared online component analyzer, an overpressure relief valve, and an emergency shut-off valve to achieve precise proportioning and uniform mixing of the two air sources. The pressure transmitter, temperature transmitter, infrared online component analyzer, overpressure relief valve, and emergency shut-off valve are all connected to the DCS intelligent control unit for interlocking control.

[0051] As one implementation method, the fine desulfurization tower 201 is filled with modified coal-based activated carbon fine desulfurization agent to remove residual H2S, COS, sulfur vapor and organic sulfur impurities, with a space velocity of 1000-2000 h⁻¹. -1 The desulfurization accuracy is ≤0.1ppm, and the sulfur penetration capacity is ≥20%, which can reduce the total sulfur content from 500mg / Nm³. 3 Reduced to 20 mg / Nm 3 The following fully meets the gas turbine intake requirements.

[0052] In one implementation, the catalytic deoxygenation tower 202 is filled with 0.5 wt% Pd / Al2O3 deoxygenation catalyst, the reaction temperature is 80–120 °C, and the space velocity is 500–1000 h⁻¹. -1 The deoxygenation accuracy is ≤0.1 vol%, to avoid excessive oxygen content leading to gas turbine detonation and blade ablation.

[0053] As one implementation, the gas turbine power generation unit 7 includes a variable frequency screw compressor 301, a pressure stabilizing tank 302, a low-NOx gas turbine generator set 303, a grid connection cabinet 304, and a low-voltage distribution cabinet 305 connected in sequence, for syngas power generation and power supply for plant production.

[0054] Furthermore, the waste heat recovery unit includes a shell-and-tube waste heat boiler 401, a steam pipeline network 402, and a steam distributor 403. The flue gas side of the waste heat boiler is connected to the exhaust port of the gas turbine. The steam outlet distributes the generated steam to the required equipment (such as the steam generator in H2S selective adsorption and regeneration, and the activated carbon activation furnace) through the steam distributor 403, so as to realize the closed-loop recovery of waste heat.

[0055] Furthermore, the H2S-CO2 mixed gas collaborative full-resource treatment system also includes a DCS intelligent control unit. The DCS intelligent control unit includes a combustible gas leakage interlock module, a gas source flow interlock module, a pressure interlock module, a component exceeding standard interlock module, a gas turbine fault interlock module, and an emergency shutdown interlock module. The combustible gas leakage interlock module is used to detect the content of combustible gases such as CH4, CO, and H2 in equipment and pipelines in real time, promptly identifying the equipment and location of combustible gas leaks. The gas source flow interlock module is used to monitor and control the inlet and outlet gas flow of each unit in real time. The pressure interlock module is used to monitor the outlet pressure fluctuations of each unit in real time. The component exceeding standard interlock module is used to detect the component content at the outlet of the syngas upgrading and purification unit in real time. The gas turbine fault interlock module is used to promptly detect gas turbine faults. The combustible gas leakage interlock module, gas source flow interlock module, pressure interlock module, component exceeding standard interlock module, and gas turbine fault interlock module are all connected to the emergency shutdown interlock module, performing emergency shutdown control based on the detection status.

[0056] The variable frequency screw compressor is equipped with a PLC variable frequency control system, which is interlocked with the gas turbine's intake pressure, unit load, and speed. The response time is ≤0.5s, and the intake pressure fluctuation is controlled to be ≤±2%.

[0057] For clarity, the present invention will be further described in detail below with reference to specific engineering embodiments and comparative examples. The following embodiments are only used to explain the present invention and are not intended to limit the scope of protection of the present invention.

[0058] This invention employs the following general performance evaluation methods: Gas component detection: online detection using an Agilent 7890A gas chromatograph; Total sulfur content detection: detection using a microcoulometric sulfur analyzer; Power generation efficiency detection: detection using the GB / T 2820-2009 standard "AC Generator Sets Driven by Reciprocating Internal Combustion Engines"; Comprehensive energy utilization rate: calculated using the GB / T 2589-2020 standard "General Rules for Calculating Comprehensive Energy Consumption".

[0059] Example 1:

[0060] Gas source composition: Catalytic synthesis gas flow rate 1500 Nm³ / h, composition: CO 35 vol%, H₂ 50 vol%, H₂S 15 mg / Nm³, N₂ balance, pressure 0.02 MPa; Activation tail gas flow rate 5000 Nm³ / h, composition: CO 25 vol%, H₂ 18 vol%, CO₂ 11 ​​vol%, H₂S 0.35 vol%, N₂ balance, tar ≤10 mg / Nm³. 3 Pressure 0.05 MPa.

[0061] Process steps:

[0062] S1: The catalytic synthesis gas is fed into the first buffer pressure stabilizing tank 101 with anti-vortex baffles for pressure stabilization, controlling the outlet pressure to 0.05 MPa and the pressure fluctuation ≤ ±4%; the high-temperature tail gas containing CO and H2 generated in the coal-based activated carbon activation section is collected in a closed manner, and after passing through cyclone dust removal, electrostatic tar removal, and molecular sieve dehydration pretreatment in sequence, it enters the second buffer pressure stabilizing tank 102 for pressure stabilization, controlling the outlet pressure to 0.05 MPa and the pressure fluctuation ≤ ±4%; then the stabilized catalytic synthesis gas and the activation tail gas are introduced into the tank at a volume ratio of 1:3.33 from the multi-layer baffled airflow distributor at the bottom of the mixing buffer pressure stabilizing tank 103 to achieve homogenization of pressure, temperature, and composition, and control the temperature of the mixed gas to 40±5℃, the pressure fluctuation ≤ ±2%, the CO+ H2 volume concentration to 52.7 vol%, and the lower heating value to 3120 kcal / Nm³;

[0063] S2 Deep Upgrading and Purification: The mixed and homogenized syngas is sequentially processed through a fine desulfurization tower, a catalytic deoxygenation tower, and a 1μm precision filter to obtain high-quality syngas specifically for gas turbines. The fine desulfurization tower has a space velocity of 1500 h⁻¹. -1 The deoxidation tower reaction temperature is 100℃ and the space velocity is 800h. -1 Control the total sulfur content at the outlet to 12 mg / Nm³, oxygen content to 0.35 vol%, dust to ≤1 mg / Nm³, and water dew point to ≤-10℃.

[0064] S3 Variable Frequency Pressurization and Stabilization Adaptation to Gas Turbine: The upgraded syngas enters the variable frequency screw compressor and is pressurized to 0.5MPa. After being stabilized by the pressure stabilizing tank, it enters the low-NOx gas turbine generator set. The compressor variable frequency system is interlocked with the gas turbine inlet pressure and the unit load to control the inlet pressure fluctuation ≤±1.5%. The rated power of the gas turbine is 1.2MW.

[0065] S4 Deep Waste Heat Recovery: The high-temperature flue gas of 350-450℃ discharged from the gas turbine enters the shell-and-tube waste heat boiler, recovers heat to generate 2.5t / h of 0.6MPa saturated steam, and all steam is reused.

[0066] Operational results: Syngas utilization rate: 99.2%; Power generation efficiency: 38.6%, an improvement of 16.8 percentage points compared to standalone power generation; The generator set operated continuously and stably for 720 hours without any shutdown or tripping faults, and the power generation load fluctuation was ≤±2%; Waste heat recovery efficiency: 86.2%; Annual electricity savings: 9.6 million kWh, and annual steam cost savings of 1.8 million yuan.

[0067] Example 2: Verification Example of Wide Operating Condition Fluctuation

[0068] Gas source parameters: The composition and pressure of the catalytic synthesis gas and the activation tail gas are the same as in Example 1. The flow rate of the catalytic synthesis gas fluctuates by ±30% (1050~1950Nm³ / h), the flow rate of the activation tail gas fluctuates by ±30% (3500~6500Nm³ / h), and the composition fluctuates by ±20%, simulating extreme working conditions in industrial settings.

[0069] Process steps: Except for step S3, which automatically adjusts the compressor frequency and gas turbine power, the rest are the same as in Example 1.

[0070] Operating results: The system operated continuously and stably for 300 hours. The generator set operated stably throughout, with a load regulation range of 0.8 to 1.6 MW and no faults. It perfectly adapted to the wide range of operating conditions and fluctuations in industrial sites.

[0071] Example 3: Low-load operating condition example

[0072] Gas source parameters: The composition and pressure of the catalytic synthesis gas and the activation tail gas are the same as in Example 1. The flow rate of the catalytic synthesis gas is 1000 Nm³ / h, and the flow rate of the activation tail gas is 3000 Nm³ / h, corresponding to the 30% low-load operation condition of the activated carbon production line.

[0073] Process steps: Except for step S3, which adjusts the compressor frequency and gas turbine power, the rest are the same as in Example 1.

[0074] Operating results: The generator set operated stably at a load of 0.7MW without any shutdown or surge faults, and the power generation efficiency was 36.2%, which is still much higher than the efficiency of standalone power generation, proving that this technology still has excellent performance under low load conditions.

[0075] Comparative Example 1: Two gas sources generate electricity independently

[0076] Gas source parameters: Same as in Example 1.

[0077] Process steps: Catalytic synthesis gas enters a small generator set separately, and activation tail gas enters another generator set separately.

[0078] Operating results: The catalytic synthesis gas generator set frequently shut down and tripped, with an average of 12 shutdowns per month and a power generation efficiency of 28%; the activated tail gas generator set had insufficient calorific value and could not operate at full load, with a power generation efficiency of 22%; the annual power generation was 1.68 million kWh less than that of Example 1; there was no waste heat recovery system, resulting in an additional annual steam consumption of 12,000 tons and an operating cost 2.2 million yuan higher than that of Example 1.

[0079] Comparative Example 2: Direct Hybrid Power Generation without Upgrading Process

[0080] Gas source parameters: Same as in Example 1.

[0081] Process steps: The two gases are directly mixed and then enter the gas turbine without desulfurization, deoxygenation and upgrading processes.

[0082] Comparison results: The total sulfur content of the mixed gas was 320 mg / Nm³, and the oxygen content was 1.2 vol%, far exceeding the gas turbine intake standard; after 3 months of operation, the gas turbine blades showed severe corrosion, carbon deposits, and ablation, resulting in equipment damage and shutdown for repair, with repair costs reaching 800,000 yuan and a significant reduction in equipment lifespan; during operation, the gas turbine experienced multiple knocking and flameout failures, making stable operation impossible.

[0083] Comparative Example 3: Direct Hybrid Power Generation Without Voltage Stabilization Design

[0084] Gas source parameters: Same as in Example 1.

[0085] Process steps: No staged pressure stabilization, mixing buffer tank, variable frequency booster design, the two gases are directly mixed and then enter the gas turbine.

[0086] Comparative results: The mixed gas pressure fluctuated by ±15%, and the calorific value fluctuated by ±20%. The gas turbine could not operate stably and frequently experienced large load fluctuations and tripping failures. The power generation efficiency was only 25%, which was 13.6 percentage points lower than that of Example 1, resulting in serious energy waste. Pressure fluctuations impacted the gas turbine equipment, increasing the equipment failure rate by 300% and significantly shortening its service life.

Claims

1. A method for combined power generation of H2S-CO2 catalytic synthesis gas and activated carbon-activated tail gas, characterized in that, Includes the following steps: S1 Syngas Merging: Catalytic syngas and activated carbon plant pretreatment gas undergo primary pressure stabilization treatment to control pressure fluctuations to ≤±5%. They are then merged at a volume ratio of 1:(3~4) and undergo secondary pressure stabilization treatment to control the temperature of the mixed gas at 40±5℃ and the pressure fluctuation to ≤±3%. Catalytic synthesis gas includes CO 30–40 vol%, H2 45–55 vol%, and H2S ≤ 20 mg / Nm³. 3 H2O ≤ 100ppm, N2 balance; The pre-treated gas in activated carbon plants includes CO 15-30 vol%, H2 10-20 vol%, CO2 8-15 vol%, H2S 0.1-0.5 vol%, and tar ≤10 mg / Nm³. 3 , N2 balance; S2 Syngas Upgrading and Purification: The stabilized syngas undergoes desulfurization, deoxygenation, and filtration sequentially to obtain a total sulfur content ≤20mg / Nm³. 3 High-quality syngas with oxygen content ≤0.5 vol%, dust ≤1 mg / Nm³, water dew point ≤-10℃, and pressure fluctuation ≤±3%; S3 Variable frequency boosting and stabilization and gas turbine power generation: The syngas obtained in step S2 is boosted to 0.4-0.6 MPa by a variable frequency screw compressor, and after being stabilized by a pressure stabilizing tank, it enters a low-NOx gas turbine generator set to generate electricity; S4 waste heat closed-loop reuse: recovers the heat from the high-temperature flue gas discharged from the gas turbine and sends it to a shell-and-tube waste heat boiler to produce saturated steam, which is then reused.

2. A combined power generation system for H2S-CO2 catalytic synthesis gas and activated carbon-activated tail gas, characterized in that, The system includes a syngas merging unit, a syngas upgrading and purification unit, a variable frequency boosting and stabilizing unit with a gas turbine power generation unit, and a waste heat recovery unit. The syngas merging unit comprises a first buffer stabilizing tank, a second buffer stabilizing tank, and a mixing buffer stabilizing tank. The syngas upgrading and purification unit includes a fine desulfurization tower, a catalytic deoxygenation tower, and a 1μm precision filter. The variable frequency boosting and stabilizing unit with a gas turbine power generation unit comprises a variable frequency screw compressor, a stabilizing tank, and a low-NOx gas turbine generator set connected in sequence. Catalytic syngas and activated carbon plant pretreatment gas undergo pressure stabilization treatment in the first and second buffer stabilizing tanks, respectively. The outlet pressure fluctuation of the first and second buffer stabilizing tanks is ≤±5%. The inlet of the mixing buffer stabilizing tank is connected to the outlets of the first and second buffer stabilizing tanks, respectively, controlling the temperature of the mixed gas to 40±5℃ and the pressure fluctuation to ≤±3%. The mixing buffer stabilizing tank, the fine desulfurization tower, the catalytic deoxygenation tower, and the 1μm precision filter are all part of the system. Precision filters are connected in sequence, and after desulfurization, deoxygenation and filtration, high-quality syngas is obtained with a total sulfur content ≤20mg / Nm³. 3 Oxygen content ≤ 0.5 vol%, dust ≤ 1 mg / Nm³ 3 The water dew point is ≤-10℃. High-quality syngas is pressurized to 0.4~0.6MPa by a variable frequency screw compressor, and after being stabilized by a pressure stabilizing tank, it enters the low-NOx gas turbine generator set to generate electricity. The waste heat recovery unit is used to convert the heat in the high-temperature flue gas generated by the power generation unit into steam.

3. The H2S-CO2 catalytic synthesis gas and activated carbon activated tail gas combined power generation system according to claim 2, characterized in that, The mixing buffer pressure stabilizing tank has a vertical structure. Inside the tank, from bottom to top, there are multiple layers of baffle-type airflow distributors, anti-vortex baffles, and static mixing elements. The mixing zone is located above the static mixing elements.

4. The H2S-CO2 catalytic synthesis gas and activated carbon activated tail gas combined power generation system according to claim 3, characterized in that, The multi-layer baffle airflow distributor is a three-layer baffle airflow distributor.

5. The H2S-CO2 catalytic synthesis gas and activated carbon activated tail gas combined power generation system according to claim 2, characterized in that, The fine desulfurization tower is filled with modified coal-based activated carbon fine desulfurization agent, with a space velocity of 1000-2000 h⁻¹. -1 Desulfurization accuracy ≤0.1ppm, sulfur penetration capacity ≥20%.

6. The H2S-CO2 catalytic synthesis gas and activated carbon activated tail gas combined power generation system according to claim 2, characterized in that, The catalytic deoxygenation tower is filled with 0.5 wt% Pd / Al2O3 deoxygenation catalyst, and the reaction temperature is 80–120℃ with a space velocity of 500–1000 h⁻¹. -1 Deoxygenation accuracy ≤ 0.1 vol.

7. The H2S-CO2 catalytic synthesis gas and activated carbon activated tail gas combined power generation system according to claim 2, characterized in that, The waste heat recovery unit includes a shell-and-tube waste heat boiler, a steam pipeline network, and a steam distribution cylinder. The flue gas side of the waste heat boiler is connected to the exhaust port of the gas turbine, and the steam outlet distributes the generated steam to the required equipment through the steam distribution cylinder.

8. The H2S-CO2 catalytic synthesis gas and activated carbon activated tail gas combined power generation system according to claim 2, characterized in that, The H2S-CO2 mixed gas synergistic resource utilization system also includes a DCS intelligent control unit. The DCS intelligent control unit includes a combustible gas leakage interlock module, a gas source flow interlock module, a pressure interlock module, a component exceeding standard interlock module, a gas turbine fault interlock module, and an emergency shutdown interlock module. The combustible gas leakage interlock module is used to detect the combustible gas content in equipment and pipelines in real time and promptly identify the equipment and location of combustible gas leaks. The gas source flow interlock module is used to monitor and control the inlet and outlet gas flow of each unit in real time. The pressure interlock module is used to monitor the outlet pressure fluctuations of each unit in real time. The component exceeding standard interlock module is used to detect the component content at the outlet of the syngas upgrading and purification unit in real time. The gas turbine fault interlock module is used to promptly detect gas turbine faults. The combustible gas leakage interlock module, gas source flow interlock module, pressure interlock module, component exceeding standard interlock module, and gas turbine fault interlock module are all connected to the emergency shutdown interlock module to perform emergency shutdown control based on the detection status.

9. The H2S-CO2 catalytic synthesis gas and activated carbon activated tail gas combined power generation system according to claim 2, characterized in that, The variable frequency screw compressor is equipped with a PLC variable frequency control system, which is interlocked with the gas turbine's intake pressure, unit load, and speed. The response time is ≤0.5s, and the intake pressure fluctuation is controlled to be ≤±2%.

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