Biomass, water vapor and pure oxygen combined gasification method and fixed bed gasification system
By optimizing the process parameters of combined biomass, steam, and pure oxygen gasification, the problem of low gasification efficiency in existing technologies has been solved, achieving efficient biomass gasification and syngas production with good flexibility and economic benefits.
Patent Information
- Application Number
- CN202511374116.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-24
- Publication Date
- 2026-01-02
AI Technical Summary
In existing biomass gasification technologies, there is a lack of systematic understanding of the process parameters for combined steam and pure oxygen gasification, resulting in low gasification efficiency and poor gas calorific value and hydrogen content.
By optimizing the gasification reaction temperature, water-carbon molar ratio, and equivalence ratio, a combined gasification method using biomass, steam, and pure oxygen is adopted. The specific steps include crushing and drying biomass raw materials, controlling the ratio of pure oxygen and steam, carrying out a fixed-bed gasification reaction, and optimizing and controlling the process through a fixed-bed gasification system.
It significantly improves biomass gasification efficiency, increases syngas yield, reduces production costs, and achieves efficient utilization of biomass resources and environmental protection.
Smart Images
Figure CN121249409A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of biomass energy engineering, and particularly relates to a method for combined gasification of biomass, water vapor and pure oxygen. BACKGROUND
[0002] With the increasing global energy demand and the increasing environmental protection awareness of the public, it is urgent to develop more efficient, clean and renewable energy. Biomass resources, as the only renewable carbon source, have the characteristics of large reserves, various types and clean environmental protection, and play an increasingly important role in clean and renewable energy. Biomass gasification technology can convert biomass raw materials into combustible gas through pyrolysis and gasification reactions under high temperature conditions, and is currently an important biomass utilization technology.
[0003] In the existing gasification technology, gasification generally needs to introduce air, oxygen (oxygen-enriched air) and water vapor and other gasification agents to react with biomass raw materials. The introduction of air for gasification is simple, low in cost and easy to implement, but the high nitrogen content in air dilutes the combustible gas, which needs to be further treated when used as a chemical synthesis gas; oxygen is directly used for gasification, and the reaction temperature, thermal efficiency and gas heat value are all high, but the cost of oxygen itself is high, and the hydrogen content in the produced gas is low; water vapor is used for biomass gasification, and the hydrogen and alkane contents in the produced gas are high, but the heat of water vapor itself cannot meet the needs of the gasification reaction. Therefore, the combined gasification of water vapor and oxygen can not only improve the thermal efficiency of gasification, but also produce high-quality hydrogen-rich synthesis gas.
[0004] At present, the process parameters of water vapor and pure oxygen combined gasification lack systematic cognition, and the combined gasification process needs to be improved to optimize the gasification temperature, water-carbon molar ratio and equivalence ratio to obtain the optimal parameter range. SUMMARY
[0005] In view of the problem that the process parameters of water vapor and pure oxygen combined gasification in the prior art need to be further optimized, the present application provides a method for combined gasification of biomass, water vapor and pure oxygen and a fixed bed gasification system applying the method, which optimizes the gasification reaction temperature, water-carbon molar ratio and equivalence ratio, can significantly improve the biomass gasification efficiency and increase the synthesis gas yield.
[0006] To solve the above technical problems, the present application provides a method for combined gasification of biomass, water vapor and pure oxygen, which comprises the following steps:
[0007] Step 1. The biomass raw material is sequentially crushed and dried to obtain biomass particles;
[0008] Step 2. The biomass particles are sent into the reaction chamber, and process gas including pure oxygen and water vapor is introduced into the reaction chamber, wherein: the ratio of the amount of pure oxygen introduced to the theoretical amount of oxygen required for complete combustion of the biomass particle raw material is the equivalence ratio, which is limited to 0.1-0.2; the ratio of the molar amount of water vapor introduced to the molar amount of carbon in the biomass particle raw material is the water-carbon molar ratio, which is limited to 1-2;
[0009] Step 3. The biomass particles, pure oxygen and water vapor undergo combined gasification reaction in the reaction chamber at a preset reaction temperature for a preset reaction time.
[0010] As a preferred embodiment of the step 1: the biomass raw material is one or any combination of forestry residues, wood chips, waste wood and agricultural waste; in another preferred embodiment, the biomass particles obtained by crushing the biomass raw material have a particle size of ≤2 mm; in still another preferred embodiment, the drying temperature of the biomass particles is 60-105℃, and the drying time is 4-6h.
[0011] As a preferred embodiment of the step 2: before the reaction chamber is operated, nitrogen is used to evacuate the air in the reaction chamber; in another preferred embodiment, the reaction chamber is heated to the preset reaction temperature before the biomass particles are sent into the reaction chamber.
[0012] As a preferred embodiment of the step 3: the preset reaction temperature for the combined gasification reaction of the biomass, pure oxygen and water vapor is 800-900℃, and the preset reaction time is 20-30min.
[0013] As a preferred embodiment of the above technical solution, the combined gasification method of the biomass, water vapor and pure oxygen further comprises the following steps:
[0014] Step 4. After the combined gasification reaction is completed, the inside of the reaction chamber is purged with nitrogen.
[0015] As a further preferred embodiment of the step 4, the nitrogen purging time is 40-50min.
[0016] To solve the above technical problems, the second aspect of the present application provides a fixed bed gasification system applying the combined gasification method of the biomass, water vapor and pure oxygen of the first aspect, which comprises a gasification unit, a gas supply unit, a condensation and drying unit and a control unit, wherein:
[0017] The gasification unit comprises a central fixed bed quartz reaction chamber for the combined gasification reaction, and a peripheral tube furnace for heating the reaction;
[0018] The gas supply unit comprises a nitrogen source, an oxygen source and a water vapor source, which are respectively connected to the fixed bed quartz reaction chamber to supply gas thereto;
[0019] The condensation drying unit comprises a condensation chamber and a drying chamber placed in an ice water bath, the gasification product of the fixed bed quartz reaction chamber is first introduced into the condensation chamber for condensation, and the gas in the condensation chamber is then introduced into the drying chamber and discharged after drying;
[0020] The control unit comprises a PID controller, a first mass flow meter, a second mass flow meter, a thermocouple and a gas pump, the first mass flow meter, the second mass flow meter and the gas pump are arranged on the gas supply path of the nitrogen source, the oxygen source and the water vapor source connected to the fixed bed quartz reaction chamber, and the gas supply amount is regulated under the control of the PID controller; the thermocouple is arranged at the fixed bed quartz reaction chamber, monitors the reaction temperature and transmits the monitoring result to the PID controller, and the PID controller is connected to the tube furnace to adjust the reaction temperature.
[0021] The embodiment of the present application provides a biomass, water vapor and pure oxygen combined gasification method and a fixed bed gasification system, by optimizing the temperature, water-carbon molar ratio and equivalent ratio of the gasification process, on the one hand, the influence of each parameter on the gasification process is explained, and on the other hand, based on different targets, the optimal parameter range is found out. The beneficial effects of the technical scheme are as follows:
[0022] 1. The gasification reaction temperature, water-carbon molar ratio and equivalent ratio are optimized, which can significantly improve the biomass gasification efficiency and increase the synthesis gas yield;
[0023] 2. Adapt to different types of biomass raw materials, good flexibility and universality;
[0024] 3. Realize the efficient utilization of biomass resources, which has important significance for environmental protection;
[0025] 4. In industrial application, the production cost can be reduced, and the economic benefit can be significantly improved. BRIEF DESCRIPTION OF DRAWINGS
[0026] The following drawings are used to provide further understanding of the present application, and constitute a part of the specification, and together with the specific embodiments, are used to explain the present application, but do not constitute a limitation on the present application.
[0027] Figure 1 The biomass, water vapor and pure oxygen combined gasification method provided by the embodiment of the present application is shown in the step flow chart.
[0028] Figure 2 For use Figure 1 The biomass, water vapor and pure oxygen combined gasification biomass system using the method is shown in the schematic diagram.
[0029] [Explanation of reference signs]
[0030] 1-gasification unit; 11-fixed bed quartz reaction chamber; 12-tube furnace;
[0031] 21-nitrogen source; 22-oxygen source; 23-water vapor source;
[0032] 3-condensation and drying unit; 31-condensation chamber; 32-drying chamber; 33-ice water bath;
[0033] 41-first mass flow meter; 42-second mass flow meter; 43-thermocouple; 44-gas pump;
[0034] 5-gas collection device;
[0035] 6-detection unit. DETAILED DESCRIPTION
[0036] To make the technical problems, technical solutions and advantages of the present application clearer, the following will be described in detail with reference to the drawings and specific embodiments.
[0037] The present application aims at the existing problems, and provides a biomass, water vapor and pure oxygen combined gasification method and a fixed bed gasification system. By carefully designing and optimizing parameters such as water-carbon molar ratio, equivalence ratio and gasification temperature, the biomass gasification reaction efficiency is significantly improved, the energy consumption is reduced, and the quality and yield of the gasification gas are improved.
[0038] To realize the above technical solutions, as shown in the accompanying drawings, Figure 1 The embodiment of the present application provides a biomass, water vapor and pure oxygen combined gasification method, and the steps include:
[0039] S1. The biomass raw material is sequentially crushed and dried to obtain biomass particles;
[0040] S2. The biomass particles are sent into the reaction chamber, and process gas including pure oxygen and water vapor is introduced into the reaction chamber, wherein: the ratio of the amount of pure oxygen introduced to the theoretical amount of oxygen required for complete combustion of the biomass particle raw material is the equivalence ratio, which is limited to 0.1-0.2; the ratio of the molar amount of water vapor introduced to the molar amount of carbon element in the biomass particle raw material is the water-carbon molar ratio, which is limited to 1-2;
[0041] S3. Under a preset reaction temperature, the biomass particles, pure oxygen and water vapor in the reaction chamber undergo combined gasification reaction according to a preset reaction time.
[0042] As an optional embodiment, it further includes step S4:
[0043] S4. After the combined gasification reaction is completed, nitrogen is used to purge the inside of the reaction chamber.
[0044] As a preferred embodiment of step S1: the biomass raw material is selected from one or more of forestry residues, sawdust, waste wood or agricultural waste; the size of the broken biomass particles is less than or equal to 2 mm; the drying temperature of the biomass particles is 60-105 DEG C, and the drying time is 4-6 h.
[0045] As a preferred embodiment of step S2: before the reaction chamber is operated, the air in the reaction chamber is first exhausted by using nitrogen; after the reaction chamber is heated to the predetermined reaction temperature, the feeding into the reaction chamber is started.
[0046] As a preferred embodiment of step S3: the preset reaction temperature of the combined gasification reaction of the biomass, pure oxygen and steam is 800-900 DEG C, and the preset reaction time is 20-30 min.
[0047] As a preferred embodiment of step S4: the time for purging the inside of the reaction chamber by nitrogen is 40-50 min.
[0048] The embodiment of the present application also provides a fixed-bed gasification system using the combined gasification method of the aforementioned biomass, steam and pure oxygen, as shown in the figure, which comprises a gasification unit 1, a gas supply unit, a condensation and drying unit 3 and a control unit, wherein: Figure 2
[0049] The gasification unit 1 comprises a central fixed-bed quartz reaction chamber 11 for the combined gasification reaction and a peripheral tube furnace 12 for heating the reaction;
[0050] The gas supply unit comprises a nitrogen source 21, an oxygen source 22 and a steam source 23, which are respectively connected to the fixed-bed quartz reaction chamber 11 to supply gas thereto;
[0051] The condensation and drying unit 3 comprises a condensation chamber 31 placed in an ice-water bath 33 and a drying chamber 32, the gasification products of the fixed-bed quartz reaction chamber 11 are first introduced into the condensation chamber 31 to be condensed, and the gas in the condensation chamber 31 is then introduced into the drying chamber 32 to be dried and discharged;
[0052] The control unit comprises a PID controller, a first mass flow meter 41, a second mass flow meter 42, a thermocouple 43 and a gas pump 44, the first mass flow meter 41, the second mass flow meter 42 and the gas pump 44 are respectively arranged on the gas supply paths of the nitrogen source 21, the oxygen source 22 and the steam source 23 connected to the fixed-bed quartz reaction chamber 11 to regulate the gas supply amount under the control of the PID controller; the thermocouple 43 is arranged at the fixed-bed quartz reaction chamber 11 to monitor the reaction temperature and transmit the monitoring result to the PID controller, and the PID controller is connected to the tube furnace 12 to adjust the reaction temperature.
[0053] The process of the combined gasification of the biomass, steam and pure oxygen using the fixed-bed gasification system is as follows:
[0054] The biomass particles obtained by crushing and drying the biomass raw material are sent into the fixed bed quartz reaction chamber 11 through a feeding device;
[0055] The fixed bed quartz reaction chamber 11 is heated by the tubular furnace 12, and the temperature in the fixed bed quartz reaction chamber 11 is monitored by the thermocouple 43 and fed back to the PID controller. The PID controller controls the actions of the first mass flow meter 41, the second mass flow meter 42 and the gas pump 44 according to the received temperature data, and controls the heating degree of the tubular furnace 12;
[0056] The oxygen source 22 and the water vapor source 23 are respectively controlled by the second mass flow meter 42 and the gas pump 44 to introduce oxygen and water vapor as process gas into the fixed bed quartz reaction chamber 11, and the nitrogen source 21 is controlled by the first mass flow meter 41 to output nitrogen to perform the emptying and purging actions of the fixed bed quartz reaction chamber 11;
[0057] Under the preset reaction time and the preset reaction temperature, the oxygen, the water vapor and the biomass particles in the fixed bed quartz reaction chamber 11 undergo a combined gasification reaction;
[0058] The reaction products in the fixed bed quartz reaction chamber 11 are discharged and sequentially pass through the condensation chamber 31 and the drying chamber 32 arranged in the ice water bath 33, and the gas containing H2 and CO is obtained after condensation and drying;
[0059] The gas produced by the fixed bed gasification system is collected by the gas collection device 5 and input into the detection unit 6 for detection.
[0060] Example 1
[0061] The walnut shells are dried at 105℃ for 4h and crushed to a particle size of 2mm or less.
[0062] The combined gasification is carried out for 20min under the conditions of 900℃, a water-carbon molar ratio of 1.5 and an equivalent ratio of 0.1 by using the fixed bed gasification system.
[0063] After the combined gasification, the generated amounts of H2 and CO corresponding to an average of per g of raw material, and the carbon conversion efficiency are detected.
[0064] Example 2
[0065] The walnut shells are dried at 105℃ for 4h and crushed to a particle size of 2mm or less.
[0066] The combined gasification is carried out for 20min under the conditions of 900℃, a water-carbon molar ratio of 2.0 and an equivalent ratio of 0.15 by using the fixed bed gasification system.
[0067] After the combined gasification, the generated amounts of H2 and CO corresponding to an average of per g of raw material, and the carbon conversion efficiency are detected.
[0068] Comparative Example 1
[0069] The walnut shell was dried at 105°C for 4h, and crushed to a particle size of 2mm or less;
[0070] The fixed bed gasification system was used to gasify for 20min at 900°C, with a water-carbon molar ratio of 1.5 and an equivalent ratio of 0.05.
[0071] After the combined gasification, the gas production was detected to obtain the average H2 and CO production per g of raw material, and the carbon conversion efficiency.
[0072] Comparative Example 2
[0073] The walnut shell was dried at 105°C for 4h, and crushed to a particle size of 2mm or less;
[0074] The fixed bed gasification system was used to gasify for 20min at 900°C, with a water-carbon molar ratio of 0.5 and an equivalent ratio of 0.1.
[0075] After the combined gasification, the gas production was detected to obtain the average H2 and CO production per g of raw material, and the carbon conversion efficiency.
[0076] Comparative Example 3
[0077] The walnut shell was dried at 105°C for 4h, and crushed to a particle size of 2mm or less;
[0078] The fixed bed gasification system was used to gasify for 10min at 900°C, with a water-carbon molar ratio of 1.5 and an equivalent ratio of 0.1.
[0079] After the combined gasification, the gas production was detected to obtain the average H2 and CO production per g of raw material, and the carbon conversion efficiency.
[0080] Comparative Example 4
[0081] The walnut shell was dried at 105°C for 4h, and crushed to a particle size of 2mm or less;
[0082] The fixed bed gasification system was used to gasify for 20min at 750°C, with a water-carbon molar ratio of 1.5 and an equivalent ratio of 0.1.
[0083] After the combined gasification, the gas production was detected to obtain the average H2 and CO production per g of raw material, and the carbon conversion efficiency.
[0084] Table 1: Gas production detection results
[0085]
[0086] From the above table, it can be seen that the biomass and steam and pure oxygen combined gasification scheme provided by the embodiment of the present application can effectively improve the yield of H2 and CO in the generated gas compared with the comparative example; after the generated H2 and CO are separated, on the one hand, they can be used as green clean fuel, and on the other hand, they can be used as industrial raw materials to synthesize high-value chemicals, reduce the use of fossil fuels, promote the transformation of energy structure; improve the carbon conversion efficiency and cold coal gas efficiency, realize energy optimization, and have important significance for environmental protection.
[0087] For the above-mentioned embodiments of the present application, the specific structure and characteristics of the scheme known to the public are not described in detail; each embodiment is described in a progressive manner, and the technical features involved in each embodiment can be combined with each other on the premise that they do not conflict with each other, and the same or similar parts between each embodiment can be referred to each other.
[0088] In the description of the present application, the terms "connection" and "communication" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances; in addition, the terms "first" and "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.
[0089] The above is the preferred embodiment of the present application, it should be pointed out that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which should also be considered to fall within the scope of the present application.
Claims
1. A method for the co-gasification of biomass, steam and pure oxygen, characterized in that, The method comprises the following steps: Step 1: crushing and drying the biomass raw material in sequence to obtain biomass particles; Step 2: feeding the biomass particles into a reaction chamber, and introducing process gas comprising pure oxygen and water vapor into the reaction chamber, wherein: the ratio of the amount of pure oxygen introduced to the theoretical amount of oxygen required for complete combustion of the biomass particle raw material is the equivalence ratio, which is limited to 0.1-0.2; the ratio of the molar amount of water vapor introduced to the molar amount of carbon in the biomass particle raw material is the water-carbon molar ratio, which is limited to 1-2; Step 3: under a preset reaction temperature, the biomass particles, pure oxygen and water vapor undergo combined gasification reaction in the reaction chamber for a preset reaction time.
2. The method of claim 1, wherein, In step 1, the biomass raw material is one or any combination of forestry residues, sawdust, waste wood and agricultural waste.
3. The method of claim 1, wherein, In step 1, the particle size of the biomass particles is ≤2 mm.
4. The method of claim 1, wherein, In step 1, the drying temperature of the biomass particles is 60-105°C, and the drying time is 4-6 h.
5. The method of claim 1, wherein, In step 2, before the reaction chamber is operated, nitrogen is used to evacuate the air in the reaction chamber.
6. The method of claim 1, wherein, In step 2, after the reaction chamber is heated to the preset reaction temperature, the biomass particles are fed into the reaction chamber.
7. The method of claim 1, wherein, In step 3, the preset reaction temperature is 800-900°C, and the preset reaction time is 20-30 min.
8. The method according to any one of claims 1 to 7, characterized in that, Step 4: after the combined gasification reaction is completed, the inside of the reaction chamber is purged with nitrogen.
9. The method of claim 8, wherein, The nitrogen purging time is 40-50 min.
10. A fixed bed gasification system using the method of gasification of biomass, water vapor and pure oxygen according to any one of claims 1 to 9, characterized in that, The method comprises a gasification unit (1), a gas supply unit, a condensation and drying unit (3) and a control unit, wherein: The gasification unit (1) comprises a fixed bed quartz reaction chamber (11) for combined gasification reaction and a tube furnace (12) for heating the reaction; The gas supply unit comprises a nitrogen source (21), an oxygen source (22) and a water vapor source (23), which are respectively connected to the fixed bed quartz reaction chamber (11) to supply gas thereto; The condensation and drying unit (3) comprises a condensation chamber (31) and a drying chamber (32) placed in an ice water bath (33), the gasification products of the fixed bed quartz reaction chamber (11) are first introduced into the condensation chamber (31) for condensation, and the gas in the condensation chamber (31) is then introduced into the drying chamber (32) for drying and then discharged; The control unit comprises a PID controller, a first mass flow meter (41), a second mass flow meter (42), a thermocouple (43) and a gas pump (44), the first mass flow meter (41), the second mass flow meter (42) and the gas pump (44) are respectively arranged on the gas supply paths of the nitrogen source (21), the oxygen source (22) and the water vapor source (23) connected to the fixed bed quartz reaction chamber (11) to control the gas supply amount under the control of the PID controller; the thermocouple (43) is arranged at the fixed bed quartz reaction chamber (11) to monitor the reaction temperature and transmit the monitoring results to the PID controller, and the PID controller is connected to the tube furnace (12) to adjust the reaction temperature.