Biomass liquid fuel and preparation method thereof

Abstract

The invention relates to the field of biomass fuels, in particular to a biomass liquid fuel and a preparation method thereof. According to the preparation method, the biomass liquid fuel is prepared by crushing, gasifying and synthesizing the municipal organic household garbage, and accurate control is realized by adding a novel catalyst and adjusting various parameters in the reaction in the production process of the biomass liquid fuel; the energy consumption of the whole system is reduced, meanwhile, the yield and quality of liquid fuel are improved, the pollution problem of urban organic garbage is solved, secondary utilization of the urban organic garbage is achieved, waste is turned into wealth, and the produced biomass liquid fuel is clean energy capable of replacing mineral fuel such as original petroleum and the like and has a good application prospect. The current green and environment-friendly production concept is met. Therefore, the preparation method disclosed by the invention has a wide application prospect and innovativeness.

Description

Technical Field

[0001] The present invention relates to the field of biomass fuels, and particularly to a biomass liquid fuel and a preparation method thereof. Background Art

[0002] The problem of treating municipal organic waste has long been a major challenge in the field of urban management. Traditional waste treatment methods, such as landfilling and incineration, although alleviating the pressure of waste accumulation to a certain extent, their inherent defects are becoming increasingly prominent. The landfilling method not only occupies a large amount of precious land resources, but may also pollute groundwater and soil due to the leachate generated by waste decomposition. The incineration method may release harmful gases, having an adverse impact on air quality, and at the same time, the ash residues generated during the incineration process also need further treatment.

[0003] With the transformation of the global energy structure and the enhancement of environmental awareness, biomass liquid fuel, as a renewable, low-carbon and environmentally friendly energy form, has gradually attracted people's attention. Converting municipal domestic waste into biomass liquid fuel can not only realize the resource utilization of waste, reduce environmental pollution, but also provide new options for energy supply and promote the diversification of the energy structure.

[0004] However, the process of converting municipal domestic waste into biomass liquid fuel is not easy. At present, although there are some technologies that attempt to gasify or ferment waste to produce liquid fuel, these technologies still face many difficulties in practical applications. For example, the treatment of by-products such as tar and ash generated during the gasification process is difficult, which affects the quality and yield of liquid fuel. At the same time, although the fermentation method has strong adaptability to raw materials, its production efficiency is low, the cycle is long, and it is difficult to meet the needs of large-scale industrial production. Therefore, there is an urgent need to develop an efficient and environmentally friendly technology for converting municipal domestic waste to achieve the large-scale production of biomass liquid fuel. Summary of the Invention

[0005] In view of the above existing technical problems, the present invention aims to provide a biomass liquid fuel and a preparation method thereof. The preparation method of this biomass liquid fuel is by gasifying and synthesizing municipal organic waste. The biomass liquid fuel prepared by this method has high purity, good quality, high yield, less energy consumption during the preparation process, and can also realize the recycling of municipal organic waste, being green, energy-saving and environmentally friendly. Therefore, the preparation method of the present invention has broad application prospects and innovation.

[0006] The present invention discloses a preparation method of a biomass liquid fuel, including the following preparation steps:

[0007] S1 Raw material selection and pretreatment: Select municipal organic waste with moisture content, crush it and screen it to obtain uniformly sized organic waste particles;

[0008] S2 Gasification reaction: Add the organic waste particles obtained in step S1 to a gasification reactor, introduce an oxidant, and set the reaction temperature to carry out a gasification reaction to generate syngas; Purify and regulate the syngas to obtain a mixed gas of carbon monoxide and hydrogen;

[0009] S3 Preparation of biomass liquid fuel: Add a catalyst to a synthesis reactor, then introduce the mixed gas of carbon monoxide and hydrogen prepared in step S2, set the reaction temperature and pressure of the reactor, carry out a Fischer-Tropsch synthesis reaction, and purify to obtain a biomass liquid fuel after the reaction ends.

[0010] Preferably, in step S1 of raw material selection and pretreatment, the water content of the municipal organic waste is 40-60%.

[0011] Preferably, in step S1 of raw material selection and pretreatment, the particle size of the organic waste particles is 100-500 μm.

[0012] Preferably, in step S2 of gasification reaction, the oxidant is a mixed gas of oxygen and water vapor.

[0013] Preferably, the volume ratio of oxygen to water vapor is 1:(1-2).

[0014] Preferably, in step S2 of gasification reaction, the reaction temperature is 800-1000 °C; the reaction time is 5-20 min.

[0015] Preferably, in step S2 of gasification reaction, the molar ratio of carbon monoxide to hydrogen is 1:(1-2).

[0016] Preferably, in step S3 of biomass liquid fuel preparation, the catalyst is a composite structure of cobalt nanoparticles and γ-Al2O3.

[0017] Preferably, in step S3 of biomass liquid fuel preparation, the reaction temperature of the reactor is 300-400 °C; the reaction pressure is 5-7 MPa; the reaction time of the Fischer-Tropsch synthesis reaction is 10-20 h.

[0018] A biomass liquid fuel, which is a biomass liquid fuel prepared by any one of the above biomass liquid fuel preparation methods.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] The present invention provides a biomass liquid fuel and a preparation method thereof. The preparation method uses urban domestic organic waste as the raw material for preparing the biomass liquid fuel, and then by precisely controlling the temperature, the proportion of gasifying agent and the reaction time in the gasification process, the yield and quality of syngas can be maximally improved, thereby enhancing the yield of the liquid fuel. The present invention adopts a cobalt-based catalyst with a nanostructure and multifunctional catalytic performance, which has higher catalytic activity, selectivity and anti-poisoning ability compared with traditional catalysts, and greatly improves the efficiency of the Fischer-Tropsch synthesis reaction and the methanol synthesis reaction. By optimizing the management of the condition parameters in the gasification and synthesis reaction processes, not only the energy consumption of the overall system is reduced, but also the yield and quality of the biomass liquid fuel are improved, having broad application prospects and innovation, and achieving the goal of efficiently converting urban organic waste into liquid fuel. Detailed implementation mode

[0021] The following embodiments are provided to better further understand the present invention, which are not limited to the best implementation mode, and do not constitute a limitation to the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with those of other prior arts falls within the protection scope of the present invention.

[0022] For those not specifying specific experimental steps or conditions in the embodiments, the operations or conditions of the conventional experimental steps described in the literature in this field can be followed. For the reagents or instruments not specifying the manufacturer, they are all conventional reagent products that can be obtained through commercial purchase.

[0023] Example 1: A preparation method of a biomass liquid fuel, comprising the following steps:

[0024] S1 Raw material selection and pretreatment: Select urban organic waste with a water content of 40% for crushing and screening to remove large particles, and obtain organic waste particles with a particle size of 500 μm.

[0025] S2 Gasification reaction: Add the organic waste particles obtained in step S1 to a gasification reaction furnace, and introduce a mixed gas of oxygen and steam as an oxidant, wherein the volume ratio of oxygen to steam is 1:1; set the reaction temperature to 800 °C and the reaction time to 10 min to carry out the gasification reaction to generate syngas; purify the syngas by the temperature swing adsorption method to remove carbon monoxide 2 and moisture in the syngas to ensure the gas purity; use the condensation separation technology to separate the liquid water and soluble organic matter in the syngas; then adjust the purified gas mixture to obtain a mixed gas with a molar ratio of carbon monoxide to hydrogen of 1:1.

[0026] S3 Preparation of biomass liquid fuel: Add a catalyst to the synthesis reactor, where the catalyst is a composite structure of cobalt nanoparticles and γ-Al2O3, and then introduce the mixed gas of carbon monoxide and hydrogen prepared in step S2. Set the reaction temperature of the reactor to 300 °C and the pressure to 5 MPa, and carry out the Fischer-Tropsch synthesis reaction for 10 h. After the reaction is completed, purify to obtain the biomass liquid fuel.

[0027] Example 2: A method for preparing biomass liquid fuel, comprising the following steps:

[0028] S1 Raw material selection and pretreatment: Select municipal organic waste with a water content of 40% and crush and screen it to remove large particles to obtain organic waste particles with a particle size of 400 μm.

[0029] S2 Gasification reaction: Add the organic waste particles obtained in step S1 to the gasification reactor, and introduce a mixed gas of oxygen and steam as the oxidant, where the volume ratio of oxygen to steam is 1:1.2; set the reaction temperature to 850 °C and the reaction time to 12 min to carry out the gasification reaction to generate syngas; purify the syngas by the temperature swing adsorption method to remove carbon dioxide and moisture in the syngas to ensure gas purity; use the condensation separation technology to separate the liquid water and soluble organic matter in the syngas; then adjust the purified gas mixture to obtain a mixed gas with a molar ratio of carbon monoxide to hydrogen of 1:1.

[0030] S3 Preparation of biomass liquid fuel: Add a catalyst to the synthesis reactor, where the catalyst is a composite structure of cobalt nanoparticles and γ-Al2O3, and then introduce the mixed gas of carbon monoxide and hydrogen prepared in step S2. Set the reaction temperature of the reactor to 350 °C and the pressure to 5.5 MPa, and carry out the Fischer-Tropsch synthesis reaction for 13 h. After the reaction is completed, purify to obtain the biomass liquid fuel.

[0031] Example 3: A method for preparing biomass liquid fuel, comprising the following steps:

[0032] S1 Raw material selection and pretreatment: Select municipal organic waste with a water content of 40% and crush and screen it to remove large particles to obtain organic waste particles with a particle size of 300 μm.

[0033] S2 Gasification reaction: Add the organic waste particles obtained in step S1 into a gasification reactor, and introduce a mixed gas of oxygen and steam as the oxidant, where the volume ratio of oxygen to steam is 1:1.5; set the reaction temperature to 900 °C and the reaction time to 15 min to carry out the gasification reaction to generate syngas; purify the syngas by the temperature swing adsorption method to remove carbon monoxide 2 and moisture in the syngas to ensure gas purity; use the condensation separation technology to separate the liquid water and soluble organic matter in the syngas; then regulate the purified gas mixture to obtain a mixed gas with a molar ratio of carbon monoxide to hydrogen of 1:1.

[0034] S3 Preparation of biomass liquid fuel: Add a catalyst into the synthesis reactor, where this catalyst is a composite structure of cobalt nanoparticles and γ-Al2O3, and then introduce the mixed gas of carbon monoxide and hydrogen prepared in step S2. Set the reaction temperature of the reactor to 400 °C and the pressure to 6 MPa to carry out the Fischer-Tropsch synthesis reaction, and the reaction time is 15 h. After the reaction is completed, purify to obtain the biomass liquid fuel.

[0035] Example 4: A method for preparing biomass liquid fuel, comprising the following steps:

[0036] S1 Raw material selection and pretreatment: Select urban organic waste with a water content of 40% for crushing and screening to remove large particles, and obtain organic waste particles with a particle size of 200 μm.

[0037] S2 Gasification reaction: Add the organic waste particles obtained in step S1 into a gasification reactor, and introduce a mixed gas of oxygen and steam as the oxidant, where the volume ratio of oxygen to steam is 1:1.7; set the reaction temperature to 950 °C and the reaction time to 17 min to carry out the gasification reaction to generate syngas; purify the syngas by the temperature swing adsorption method to remove carbon monoxide 2 and moisture in the syngas to ensure gas purity; use the condensation separation technology to separate the liquid water and soluble organic matter in the syngas; then regulate the purified gas mixture to obtain a mixed gas with a molar ratio of carbon monoxide to hydrogen of 1:1.

[0038] S3 Preparation of biomass liquid fuel: Add a catalyst into the synthesis reactor, where this catalyst is a composite structure of cobalt nanoparticles and γ-Al2O3, and then introduce the mixed gas of carbon monoxide and hydrogen prepared in step S2. Set the reaction temperature of the reactor to 450 °C and the pressure to 6.5 MPa to carry out the Fischer-Tropsch synthesis reaction, and the reaction time is 17 h. After the reaction is completed, purify to obtain the biomass liquid fuel.

[0039] Example 5: A method for preparing biomass liquid fuel, comprising the following steps:

[0040] S1 Raw material selection and pretreatment: Select municipal organic waste with a water content of 40%, crush it, and screen out large particles to obtain organic waste particles with a particle size of 100 μm.

[0041] S2 Gasification reaction: Add the organic waste particles obtained in step S1 to a gasification reactor, and introduce a mixed gas of oxygen and steam as an oxidant, where the volume ratio of oxygen to steam is 1:2; set the reaction temperature to 1000 °C and the reaction time to 20 min to carry out the gasification reaction to generate syngas; purify the syngas by the temperature swing adsorption method to remove carbon monoxide 2 and moisture in the syngas to ensure gas purity; use the condensation separation technology to separate the liquid water and soluble organic matter in the syngas; then regulate the purified gas mixture to obtain a mixed gas with a molar ratio of carbon monoxide to hydrogen of 1:1.

[0042] S3 Preparation of biomass liquid fuel: Add a catalyst to the synthesis reactor, where this catalyst is a composite structure of cobalt nanoparticles and γ-Al2O3, and then introduce the mixed gas of carbon monoxide and hydrogen prepared in step S2. Set the reaction temperature of the reactor to 500 °C and the pressure to 7 MPa to carry out the Fischer-Tropsch synthesis reaction for 20 h. After the reaction is completed, purify to obtain the biomass liquid fuel.

[0043] Examples 1 to 5 screen the condition parameters such as reaction temperature, reaction time, reaction pressure, and raw material particle size in the preparation method. First, detect the purity, viscosity, ash content, calorific value, and combustion efficiency of the biomass liquid fuel prepared in Examples 1 to 5. The detection results are shown in the following table:

[0044]

[0045] It can be seen from the detection data in the above table that from Example 1 to Example 5, the purity shows a gradually increasing trend. The purity of Example 5 is the highest, reaching 97.8%. This phenomenon indicates that with the increase of gasification temperature and the extension of reaction time, the quality of syngas gradually improves, impurities can be effectively removed, and thus the purity of biomass liquid fuel is improved. The increase in purity reflects that a higher temperature gasification reaction is more conducive to the optimization of syngas and impurity removal, thereby improving the quality of the final fuel.

[0046] The viscosity shows a decreasing trend with the change of reaction conditions, decreasing from 4.2 MPa·s in Example 1 to 2.8 MPa·s in Example 5. The decrease in viscosity means that the liquid fuel has better fluidity, which helps for more complete combustion during the combustion process, reduces the coagulability of the fuel, and reduces the solid residue during fuel use. This is because high-temperature gasification and syngas regulation improve the molecular structure of the liquid fuel, making it more uniform and enhancing its fluidity.

[0047] The ash content gradually decreases, from 1.2% in Example 1 to 0.3% in Example 5. The decrease in ash indicates a reduction in the content of inorganic impurities (such as minerals) in the fuel, thereby increasing the energy density and combustion efficiency of the fuel. Through the optimization of high-temperature gasification and condensation separation technologies, the ash content is significantly reduced, which proves the effective removal of solid impurities during the gasification process.

[0048] As the temperature and reaction time increase, the calorific value gradually increases, from 42.5 MJ / kg in Example 1 to 46.0 MJ / kg in Example 5. This indicates that higher temperatures and optimized gasification processes contribute to increasing the energy density of biomass liquid fuels. The combustion efficiency gradually increases in the examples, from 98.5% in Example 1 to 99.5% in Example 5. This trend shows that high-temperature gasification reactions and the optimized use of catalysts enable more complete combustion of the liquid fuel and more efficient energy conversion. The increase in calorific value and combustion efficiency means that the fuel can provide more energy, release energy more effectively, reduce energy consumption, reduce harmful emissions, and improve the environmental performance of the fuel.

[0049] The biomass liquid fuel in Example 5 performs best, with the highest purity, calorific value, and combustion efficiency, and the lowest viscosity and ash content. This shows that high-temperature gasification and the use of optimized catalysts are crucial for improving fuel performance.

[0050] Example 6: Screen the molar ratio of carbon monoxide to hydrogen in the syngas obtained in the S2 gasification reaction step, with all other conditions being the same as in Example 5. Detect the purity, viscosity, ash, calorific value, and combustion efficiency of the biomass liquid fuels prepared at different volume ratios. The detection results are shown in the following table:

[0051]

[0052] From the detection data in the above table, it can be seen that: as the volume ratio of carbon monoxide to hydrogen changes, the purity of the fuel gradually decreases; the viscosity increases; the ash content increases; the calorific value and combustion efficiency decrease. This is because changing the molar ratio leads to an increase in by-products or incomplete reactants generated during the reaction, thereby affecting the purity of the fuel. When the molar ratio of carbon monoxide to hydrogen is 1:1, the biomass liquid fuel has the best purity, calorific value, and combustion efficiency. Therefore, optimizing the volume ratio of the gas, especially the ratio of carbon monoxide and hydrogen, may help improve the performance and economy of the fuel.

[0053] Obviously, the above embodiments are merely examples given for clear illustration and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to exhaustively list all implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the present invention.

Claims

1. A method for preparing biomass liquid fuel, characterized in that: The following steps are involved: S1. Raw material selection and pretreatment: Select urban organic waste with water content, crush it and sieve it to obtain organic waste particles of uniform size; S2 gasification reaction: adding the organic waste particles obtained in step S1 to a gasification reactor, introducing an oxidant, setting a reaction temperature for gasification reaction to generate synthesis gas; purifying and regulating the synthesis gas to obtain a mixed gas of carbon monoxide and hydrogen; S3 Preparation of biomass liquid fuel: Add a catalyst to the synthesis reactor, then introduce the mixed gas of carbon monoxide and hydrogen prepared in step S2, set the reaction temperature and pressure of the reactor, carry out Fischer-Tropsch synthesis reaction, and purify after the reaction to obtain biomass liquid fuel.

2. The method for preparing a biomass liquid fuel according to claim 1, characterized in that: In the step S1 of selecting and pre-treating raw materials, the water content of the urban organic waste is 40-60%.

3. The method for preparing a biomass liquid fuel according to claim 1, characterized in that: In the step S1 of selecting and pre-treating raw materials, the particle size of the organic waste particles is 100 to 500 μm.

4. The method for preparing a biomass liquid fuel according to claim 1, characterized in that: In the S2 gasification reaction step, the oxidant is a mixed gas of oxygen and water vapor.

5. The method for preparing a biomass liquid fuel according to claim 4, characterized in that: The volume ratio of oxygen to water vapor is 1:(1-2).

6. The method for preparing a biomass liquid fuel according to claim 4, characterized in that: In the S2 gasification reaction step, the reaction temperature is 800-1000° C. and the reaction time is 5-20 min.

7. The method for preparing a biomass liquid fuel according to claim 4, characterized in that: In the S2 gasification reaction step, the molar ratio of carbon monoxide to hydrogen is 1:(1-2).

8. The method for preparing a biomass liquid fuel according to claim 4, characterized in that: In the S3 biomass liquid fuel preparation step, the catalyst is a composite structure of cobalt nanoparticles and γ-Al2O3.

9. The method for preparing a biomass liquid fuel according to claim 4, characterized in that: In the S3 biomass liquid fuel preparation step, the reaction temperature of the reactor is 300-400° C.; the reaction pressure is 5-7 MPa; and the reaction time of the Fischer-Tropsch synthesis reaction is 10-20 h.

10. The biomass liquid fuel prepared by the method for preparing a biomass liquid fuel according to any one of claims 1 to 9.

Images