A method for preparing biomass pellet fuel that reduces PM1 particulate emissions

Abstract

This invention belongs to the field of bio-based material preparation and provides a method for preparing biomass pellet fuel that reduces PM1 particulate emissions. The method includes: uniformly mixing solid waste from reed preparation with pulping waste from various stages of the reed pulping process; sealing and allowing the mixture to stand for 4–6 hours to obtain a mixture; maintaining the mixture under a pressure of 10–12 MPa for 4–5 minutes; demolding; and allowing it to stand at room temperature for 6–12 hours to obtain the final product. Alternatively, concentrated liquid waste from various stages of the reed pulping process can be mixed with solid waste from reed preparation in a certain proportion to better bind and shape the fuel, thus preparing biomass pellet fuel that can reduce PM1 particulate emissions.

Description

Technical Field

[0001] This invention belongs to the field of bio-based material preparation, and in particular to a method for preparing biomass pellet fuel that reduces PM1 particulate emissions. Background Technology

[0002] The information disclosed in this background section is intended only to enhance understanding of the overall background of the invention and is not necessarily to be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

[0003] In recent years, straw has been primarily processed through composting. However, composting alone cannot meet the demand for straw recycling. Using straw as a raw material for pulping and papermaking is also a biomass resource utilization technology. However, using straw fibers as a raw material for pulping and papermaking generates some solid waste and waste liquid during the production process. Both of these wastes are not effectively utilized, and indiscriminate disposal or discharge not only wastes resources but also easily causes environmental pollution.

[0004] One of the main methods for treating agricultural waste plant fibers is combustion. However, biomass is a highly polluting fuel with low thermal efficiency when directly burned, resulting in large emissions of particulate matter and dense smoke, which pollutes the environment. Therefore, it is crucial to use biomass solid waste as raw material and process it through drying, crushing, mixing, and extrusion to produce a new type of clean fuel. This is especially important because the combustion process generates fine particulate matter that enters the atmosphere and can flocculate with various harmful substances to form aerosols, causing serious environmental pollution and harm to humans. The fine particulate matter produced by combustion is closely related to alkali metals, sulfur, chlorine, and silicon, and these elements are present in solid waste and pulping wastewater. Therefore, how to utilize solid waste in a resource-efficient manner is a pressing technical challenge for the paper industry. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method for preparing biomass pellet fuel that reduces PM1 particulate emissions. Liquid waste generated during each stage of the reed pulping process is concentrated and then mixed with reed residue solid waste generated during the material preparation stage in a specific ratio to better bind and shape the fuel, thereby preparing biomass pellet fuel that can reduce PM1 particulate emissions.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for preparing biomass pellet fuel that reduces PM1 particulate emissions, comprising:

[0008] The solid waste from the reed preparation section is mixed evenly with the pulping waste liquid from each section of the reed pulping process. After sealing, it is left to stand for 4-6 hours to obtain a mixture.

[0009] The mixture is maintained at a pressure of 10-12 MPa for 4-5 minutes, demolded, and left to stand at room temperature for 6-12 hours to obtain the final product.

[0010] In a second aspect, the present invention provides biomass pellet fuel prepared by the above-described method.

[0011] A third aspect of the present invention provides the application of the above-described biomass pellet fuel in the field of clean energy.

[0012] Beneficial effects of the present invention

[0013] (1) This invention uses solid waste and pulping waste liquid generated in the material preparation section of reed pulping process as raw materials, mixes them in a certain proportion, and compresses them to prepare biomass shaped fuel pellets, which has the advantages of being clean, economical and sustainable.

[0014] (2) The present invention is easy and simple to prepare and has strong practicality.

[0015] (3) The biomass pellet fuel of the present invention has good forming effect, high energy density, small volume, and is easy to store, transport and utilize.

[0016] (4) The biomass pellet fuel of the present invention can reduce PM1 particulate emissions and is a clean and green product. Detailed Implementation

[0017] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0018] As described in the background art, during the biomass combustion process, fine particulate matter is generated and enters the atmosphere, where it flocculates with various harmful substances to form aerosols, causing serious environmental pollution. The generation of fine particulate matter generated by combustion is closely related to alkali metals, sulfur, chlorine and silicon, and related elements are found in solid waste and pulping waste liquid.

[0019] One of the objectives of this invention is to solve the problem of recycling and utilizing reed residue solid waste and pulping waste liquid.

[0020] The second objective of this invention is to provide a method for preparing biomass pellet fuel that reduces PM1 particulate emissions.

[0021] Therefore, the present invention provides a method for preparing biomass pellet fuel that reduces PM1 particulate emissions by utilizing elements in pulping wastewater, comprising:

[0022] Solid waste from reeds is mixed evenly with pulping waste liquid and then compressed into pellet fuel.

[0023] In some embodiments, the reed waste solid waste refers to all components of solid waste discarded in the pulp and paper preparation section, and the pulping waste liquid refers to the pulping waste liquid from large-scale production in a paper mill, which, after concentration, yields a waste liquid with a solid content of approximately 53%.

[0024] In some embodiments, the mass of the pulping waste liquid is 0-15% of the reed solid waste.

[0025] In some embodiments, after the biomass pellet fuel components are fully mixed, they are sealed and left to stand for 4 to 6 hours to allow the liquid to spread evenly and then dried to balance the material ratio.

[0026] In some embodiments, solid waste pellet fuel is extruded using a hydraulic press.

[0027] In some embodiments, the prepared biomass pellet fuel is used to collect PM1 particles by combustion in a tubular furnace, wherein the combustion conditions are a temperature of 1000–1200 K and an air flow rate of 0.1–0.2 L / min, and the particle size of the PM1 particles collected by the water displacement method is measured using a Malvern particle size analyzer.

[0028] In some embodiments, the specific preparation steps of the biomass pellet fuel are as follows: Pulping waste liquid is added to reed solid waste and stirred for 30 minutes; after sealing, it is allowed to stand for 4–6 hours; a mixed sample is weighed and placed into the extrusion sleeve of a hydraulic press, moved to the extrusion platform of a testing machine, and when the pressure reaches 10 MPa, the movement is stopped and maintained for 5 minutes before demolding; the biomass pellets are then placed at room temperature for 6–12 hours. The biomass pellet fuel is burned in a tubular furnace, and PM1 particles are collected using the water displacement method. The combustion conditions are: temperature 1000–1200 K, air velocity 0.1–0.2 L / min. The PM1 particle emissions of the biomass pellet fuel, as well as its related combustion performance and physical properties, are measured.

[0029] This invention aims to utilize the solid waste residue generated during the material preparation stage of reed pulping and the liquid waste generated during the pulping process to prepare inexpensive and environmentally friendly biomass pellet fuel, thereby solving the problem of resource utilization of solid waste and waste liquid in the pulping process.

[0030] The present invention will be further described in detail below with reference to specific embodiments. It should be noted that the specific embodiments are explanations of the present invention and not limitations thereof.

[0031] In the following embodiments, "reed waste solid waste" refers to solid waste generated in the pulping and preparation section. It means that when pulping and papermaking enterprises use reed fiber raw materials to make pulp and paper, the reed fiber raw materials are first mechanically cut into specified sizes, and then screened to remove unqualified fiber and non-fiber impurities, which are called reed fiber waste. The reed waste includes impurities such as dust.

[0032] The reed pulping process uses a biochemical mechanical pulping method. The "collected pulping waste liquid" includes: waste liquid from the reed grinding section and waste liquid from the alkali impregnation section. After concentration, the waste liquid has a solid content of 53%.

[0033] Raw material analysis:

[0034] The test methods were as follows: the contents of cellulose, hemicellulose and lignin in the raw materials were determined by the NREL method, the elemental composition analysis was performed by an automatic elemental analyzer, and the metal ions in the pulping waste liquid were detected by inductively coupled plasma mass spectrometry (ICP-MS). The test results are shown in Tables 1 and 2.

[0035] Table 1. Chemical composition and elemental composition analysis of reed waste residue (%)

[0036]

[0037] Table 2. Metal ion analysis of pulping waste liquid (mg / L)

[0038]

[0039] Example 1:

[0040] (1) Mixing biomass raw materials: Add pulping waste liquid (0%) to reed waste residue solid waste and stir for 30 minutes, seal and let stand for 4-6 hours;

[0041] (2) Preparation of biomass pellet fuel: Weigh the mixed sample and put it into the extrusion sleeve of the hydraulic press. Move it to the extrusion platform of the test machine. When the pressure reaches 10MPa, stop moving and maintain it for 5 minutes before demolding. Place the biomass pellets at room temperature for 12 hours to finally obtain biomass pellet fuel.

[0042] (3) Collection of PM1 particles: PM1 particles are collected by burning biomass pellet fuel in a tubular furnace and using the drainage method. The combustion conditions are: temperature 1200K and air flow rate 0.1L / min.

[0043] The calorific value of the biomass pellet fuel prepared in this embodiment is 12118±33 J·g. -1 It has a drop and breakage resistance of 99.93%, and the particle size of the emitted PM1 particles is between 350 and 800 nm, with an emission amount of 4.05 mg / g.

[0044] Example 2:

[0045] (1) Mixing biomass raw materials: Add pulping waste liquid (5%) to reed waste residue solid waste and stir for 30 minutes, seal and let stand for 4-6 hours;

[0046] (2) Preparation of biomass pellet fuel: Weigh the mixed sample and put it into the extrusion sleeve of the hydraulic press. Move it to the extrusion platform of the test machine. When the pressure reaches 10MPa, stop moving and maintain it for 5 minutes before demolding. Place the biomass pellets at room temperature for 12 hours to finally obtain biomass pellet fuel B.

[0047] (3) Collection of PM1 particles: PM1 particles are collected by burning biomass pellet fuel in a tubular furnace and using the drainage method. The combustion conditions are: temperature 1200K and air flow rate 0.1L / min.

[0048] The calorific value of the biomass pellet fuel prepared in this embodiment is 10423±28 J·g. -1 It has a drop and breakage resistance of 99.95%, and the particle size of the emitted PM1 particles is between 120 and 450 nm, with an emission amount of 0.35 mg / g.

[0049] Example 3:

[0050] (1) Mixing biomass raw materials: Add pulping waste liquid (10%) to reed waste residue solid waste and stir for 30 minutes, seal and let stand for 4-6 hours;

[0051] (2) Preparation of biomass pellet fuel: Weigh the mixed sample and put it into the extrusion sleeve of the hydraulic press. Move it to the extrusion platform of the test machine. When the pressure reaches 10MPa, stop moving and maintain it for 5 minutes before demolding. Place the biomass pellets at room temperature for 12 hours to finally obtain biomass pellet fuel C.

[0052] (3) Collection of PM1 particles: PM1 particles are collected by burning biomass pellet fuel in a tubular furnace and using the drainage method. The combustion conditions are: temperature 1200K and air flow rate 0.1L / min.

[0053] The calorific value of the biomass pellet fuel prepared in this embodiment is 8656±35 J·g. -1 It has a drop and breakage resistance of 99.97%, and the PM1 particles it emits have a particle size between 200 and 600 nm, with an emission amount of 0.15 mg / g.

[0054] Example 4:

[0055] (1) Mixing biomass raw materials: Add pulping waste liquid (15%) to reed waste solid waste and stir for 30 minutes, seal and let stand for 4-6 hours;

[0056] (2) Preparation of biomass pellet fuel: Weigh the mixed sample and put it into the extrusion sleeve of the hydraulic press. Move it to the extrusion platform of the test machine. When the pressure reaches 10MPa, stop moving and maintain it for 5 minutes before demolding. Place the biomass pellets at room temperature for 12 hours to finally obtain biomass pellet fuel D.

[0057] (3) Collection of PM1 particles: PM1 particles are collected by burning biomass pellet fuel in a tubular furnace and using the drainage method. The combustion conditions are: temperature 1200K and air flow rate 0.1L / min.

[0058] The calorific value of the biomass pellet fuel prepared in this embodiment is 7966±37 J·g. -1 It has a drop resistance of 99.95%, and the PM1 particles it emits have a particle size between 125 and 550 nm, with an emission amount of 0.55 mg / g.

[0059] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. The application of a biomass pellet fuel in reducing PM1 particulate emissions, characterized in that, The method for preparing the biomass pellet fuel includes: Mix the solid waste from the reed preparation section with the pulping waste liquid from each section of the reed pulping process, seal and let stand for 4-6 hours to obtain a mixture. The mixture is maintained at a pressure of 10-12 MPa for 4-5 minutes, demolded, and allowed to stand at room temperature for 6-12 hours to obtain the final product; the mass of the pulping waste liquid is 5-10% of the solid waste from reed residue. The pulping waste liquid generated in each section of the reed pulping process includes waste liquid from the reed grinding section and waste liquid from the alkali impregnation section.

2. The application of biomass pellet fuel as described in claim 1 in reducing PM1 particulate emissions, characterized in that, It is formed by extrusion using a hydraulic press.

3. The application of biomass pellet fuel as described in claim 1 in reducing PM1 particulate emissions, characterized in that, The mixture is placed into the extrusion sleeve of the hydraulic press and moved to the extrusion platform of the testing machine for pressurization.

4. The application of biomass pellet fuel as described in claim 1 in reducing PM1 particulate emissions, characterized in that, The mixing time is 30-40 minutes.

5. The application of biomass pellet fuel as described in claim 1 in reducing PM1 particulate emissions, characterized in that, Mixing is carried out under mechanical stirring.

6. The application of biomass pellet fuel as described in claim 1 in reducing PM1 particulate emissions, characterized in that, It also includes steps for collecting emitted PM1 particles.

7. The application of biomass pellet fuel as described in claim 6 in reducing PM1 particulate emissions, characterized in that, The specific steps for collecting and emitting PM1 particles are as follows: burning biomass pellet fuel and collecting PM1 particles by water drainage, wherein the combustion conditions are a temperature of 1000~1200 K and an air velocity of 0.1~0.2 L / min.

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