A high-volume biomass ash brick, its preparation method and application

Abstract

This invention relates to a high-volume biomass ash brick, its preparation method, and its application, belonging to the technical field of biomass ash bricks. The invention modifies polypropylene fibers by grafting sulfonic acid groups and phosphonate groups onto the fiber surface, improving the hydrophilicity of the polypropylene fibers and making them easier to wet. This effectively inhibits the agglomeration of polypropylene fibers, allowing them to be uniformly dispersed in the mixture and better bear the external stress on the biomass ash brick. Furthermore, the phosphonate groups on the polypropylene fiber surface effectively improve the loading efficiency of nano-alumina on the polypropylene fiber surface. This nano-alumina can react with the quicklime in the cement hydration products to form pozzolanic material, effectively improving the overall strength of the polypropylene fiber skeleton.

Description

Technical Field

[0001] This invention belongs to the technical field of biomass ash bricks, specifically relating to a high-volume biomass ash brick, its preparation method, and its application. Background Technology

[0002] With the rapid development of global industrialization, humanity is facing the severe challenge of increasingly depleted natural resources. The production of traditional sintered clay bricks not only consumes a large amount of precious arable clay, but its high-temperature sintering process also consumes a lot of energy. Against this backdrop, energy-saving and environmentally friendly biomass ash non-fired bricks have shown broad research prospects.

[0003] Biomass ash is the solid residue produced after the combustion of biomass fuels in power generation, heating, or industrial production. With the global emphasis on renewable energy, the biomass power generation industry has expanded rapidly, generating a massive amount of biomass ash. Biomass ash typically contains high levels of amorphous silica and alumina, possessing potential cementing activity. Applying biomass ash to the preparation of non-fired bricks can effectively reduce environmental pressure and carbon footprint. However, biomass ash bricks are usually quite brittle. To address the brittleness of biomass ash bricks and prepare high-value-added biomass ash bricks, this invention provides a high-volume biomass ash brick, its preparation method, and its application. Summary of the Invention

[0004] The purpose of this invention is to provide a high-volume biomass ash brick, its preparation method, and its application, in order to solve the problems mentioned in the background art.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A method for preparing high-volume biomass ash bricks includes the following steps:

[0007] The first step involves loading vinyl phosphate chloride onto the surface of polypropylene fibers by irradiation grafting, followed by esterification with hydroxyethyl sulfonic acid to obtain modified polypropylene fibers.

[0008] The second step is to load nano-alumina onto the surface of modified polypropylene fibers to obtain polypropylene fibers loaded with nano-alumina.

[0009] The third step is to mix the crushed, sieved, washed and dried biomass ash with cement, lime, polypropylene fiber loaded with nano-alumina and fine aggregate to obtain a mixture.

[0010] Step 4: Add water and water-reducing agent to the mixture, stir and mix evenly to obtain the mixture. Pour the mixture into the mold, compact it, demold it and cure it to obtain a high-volume biomass ash brick.

[0011] Furthermore, the length of the polypropylene fiber is 8–12 mm.

[0012] Furthermore, the particle size of the biomass ash residue after screening is 8–100 mesh.

[0013] Furthermore, the lime is quicklime.

[0014] Furthermore, the fine aggregate is river sand, with a particle size of 8 to 100 mesh.

[0015] Furthermore, the water-reducing agent is a polycarboxylate water-reducing agent.

[0016] Furthermore, the mass ratio of biomass ash, cement, lime, polypropylene fiber loaded with nano-alumina, fine aggregate, water, and water-reducing agent is 50-60:10-12:5-6:0.5-0.6:25-30:10-12:0.2-0.24.

[0017] A high-volume biomass ash brick is prepared by any of the above-mentioned preparation methods.

[0018] Application of a high-volume biomass ash brick, and its application in the building materials industry.

[0019] This invention has at least one of the following beneficial effects:

[0020] This invention modifies polypropylene fibers by grafting sulfonic acid groups onto the surface of the fibers. The sulfonic acid groups improve the hydrophilicity of the polypropylene fibers, making them easier to wet and effectively inhibiting the aggregation between the fibers. This allows the polypropylene fibers to be evenly dispersed in the mixture, better bearing the external stress on the biomass ash bricks. In addition, the negatively charged sulfonic acid groups can also generate electrostatic forces, i.e. ionic bonds, with the positively charged calcium ions in the cement hydration products, improving the interfacial adhesion between the polypropylene fibers and cement.

[0021] This invention modifies polypropylene fibers by grafting phosphonate groups onto the fiber surface. The negatively charged sulfonic acid groups on the polypropylene fiber surface can electrostatically adsorb nano-alumina, while the phosphate groups have a high affinity for aluminum ions. The synergistic effect of these two groups can effectively improve the loading efficiency of nano-alumina on the polypropylene fiber surface. The nano-alumina loaded on the polypropylene fiber surface can undergo a pozzolanic reaction with quicklime in cement hydration products, consuming harmful quicklime and forming a strong CSH gel on the polypropylene fiber surface, effectively improving the overall strength of the polypropylene fiber skeleton.

[0022] This invention modifies polypropylene fibers, effectively improving the interfacial bonding ability between polypropylene fibers and cement and the strength of the polypropylene fiber skeleton. This effectively improves the toughness and crack resistance of biomass ash bricks, compensates for the brittleness caused by increasing the amount of biomass ash, and improves the utilization rate of biomass ash. Detailed Implementation

[0023] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] The raw materials used in this invention are not particularly restricted in terms of their source; they can be purchased from the market or prepared using conventional methods known to those skilled in the art. Example

[0025] A method for preparing high-volume biomass ash bricks includes the following steps:

[0026] Step 1: 1.5 parts by mass of polypropylene fibers with a length of 8-12 mm were cleaned and placed in an irradiation grafting tube. 100 parts by mass of a 15% vinyl phosphoryl chloride acetone solution were added to the irradiation grafting tube. Nitrogen gas was introduced to purge the air from the irradiation grafting tube before irradiation grafting. After grafting, the polypropylene fibers were filtered out, washed with acetone, and dried. Then, the dried polypropylene fibers, 6 parts by mass of hydroxyethyl sulfonic acid, 4 parts by mass of triethylamine, and 40 parts by mass of acetone were mixed in a three-necked flask equipped with a thermometer and a reflux condenser. The mixture was stirred with a magnetic stirrer and reacted at 45°C for 24 hours. After the reaction was completed, the polypropylene fibers were filtered out, washed with acetone and deionized water in sequence, and dried to obtain modified polypropylene fibers.

[0027] Step 2: 10 parts by mass of nano-alumina, 1 part by mass of polyvinylpyrrolidone, and 89 parts by mass of deionized water were mixed and ultrasonically dispersed to obtain a nano-alumina suspension. Then, 1 part by mass of modified polypropylene fiber was mixed into a three-necked flask equipped with a thermometer. After turning on the magnetic stirrer, the system temperature was controlled at 50℃ and the loading was carried out for 3 hours. After the loading was completed, the polypropylene fiber was filtered out, washed with deionized water, and dried to obtain polypropylene fiber loaded with nano-alumina. The loading rate of the polypropylene fiber loaded with nano-alumina was calculated to be 12.4% after weighing.

[0028] The third step is to mix 50 parts by weight of biomass ash residue with a particle size of 8-100 mesh after crushing, sieving, washing and drying with 10 parts by weight of cement, 5 parts by weight of quicklime, 0.5 parts by weight of polypropylene fiber loaded with nano alumina and 25 parts by weight of river sand with a particle size of 8-100 mesh to obtain a mixture.

[0029] Step 4: Add 10 parts by weight of water and 0.2 parts by weight of polycarboxylate superplasticizer to the mixture, stir and mix evenly to obtain the mixture. Pour the mixture into the mold, compact it, demold it and cure it to obtain a high-volume biomass ash brick.

[0030] A high-volume biomass ash brick is prepared by any of the above-mentioned preparation methods.

[0031] Application of a high-volume biomass ash brick, and its application in the building materials industry. Example

[0032] A method for preparing high-volume biomass ash bricks includes the following steps:

[0033] Step 1: 1.5 parts by mass of polypropylene fibers with a length of 8-12 mm were cleaned and placed in an irradiation grafting tube. 100 parts by mass of a 15% vinyl phosphoryl chloride acetone solution were added to the irradiation grafting tube. Nitrogen gas was introduced to purge the air from the irradiation grafting tube before irradiation grafting. After grafting, the polypropylene fibers were filtered out, washed with acetone, and dried. Then, the dried polypropylene fibers, 6 parts by mass of hydroxyethyl sulfonic acid, 4 parts by mass of triethylamine, and 40 parts by mass of acetone were mixed in a three-necked flask equipped with a thermometer and a reflux condenser. The mixture was stirred with a magnetic stirrer and reacted at 50°C for 24 hours. After the reaction was completed, the polypropylene fibers were filtered out, washed with acetone and deionized water in sequence, and dried to obtain modified polypropylene fibers.

[0034] Step 2: 10 parts by mass of nano-alumina, 1 part by mass of polyvinylpyrrolidone, and 89 parts by mass of deionized water were mixed and ultrasonically dispersed to obtain a nano-alumina suspension. Then, 1 part by mass of modified polypropylene fiber was mixed into a three-necked flask equipped with a thermometer. After turning on the magnetic stirrer, the system temperature was controlled at 55℃ and the loading was carried out for 4 hours. After the loading was completed, the polypropylene fiber was filtered out, washed with deionized water, and dried to obtain polypropylene fiber loaded with nano-alumina. The loading rate of the polypropylene fiber loaded with nano-alumina was calculated to be 14.7% after weighing.

[0035] The third step is to mix 55 parts by weight of biomass ash residue with a particle size of 8-100 mesh after crushing, sieving, washing and drying with 11 parts by weight of cement, 5.5 parts by weight of quicklime, 0.55 parts by weight of polypropylene fiber loaded with nano alumina and 27.5 parts by weight of river sand with a particle size of 8-100 mesh evenly to obtain a mixture.

[0036] Step 4: Add 11 parts by weight of water and 0.22 parts by weight of polycarboxylate superplasticizer to the mixture, stir and mix evenly to obtain the mixture. Pour the mixture into the mold, compact it, demold it and cure it to obtain a high-volume biomass ash brick.

[0037] A high-volume biomass ash brick is prepared by any of the above-mentioned preparation methods.

[0038] Application of a high-volume biomass ash brick, and its application in the building materials industry. Example

[0039] A method for preparing high-volume biomass ash bricks includes the following steps:

[0040] Step 1: 1.5 parts by weight of polypropylene fibers with a length of 8-12 mm were cleaned and placed in an irradiation grafting tube. 100 parts by weight of a 15% vinyl phosphoryl chloride acetone solution were added to the irradiation grafting tube. Nitrogen gas was introduced to purge the air from the irradiation grafting tube before irradiation grafting. After grafting, the polypropylene fibers were filtered out, washed with acetone, and dried. The dried polypropylene fibers, 6 parts by weight of hydroxyethyl sulfonic acid, 4 parts by weight of triethylamine, and 40 parts by weight of acetone were then mixed in a three-necked flask equipped with a thermometer and a reflux condenser. The mixture was stirred with a magnetic stirrer and reacted at 55°C for 24 hours. After the reaction was completed, the polypropylene fibers were filtered out, washed with acetone and deionized water in sequence, and then dried to obtain modified polypropylene fibers.

[0041] Step 2: 10 parts by mass of nano-alumina, 1 part by mass of polyvinylpyrrolidone, and 89 parts by mass of deionized water were mixed and ultrasonically dispersed to obtain a nano-alumina suspension. Then, 1 part by mass of modified polypropylene fiber was mixed into a three-necked flask equipped with a thermometer. After turning on the magnetic stirrer, the system temperature was controlled at 60℃ and continuously loaded for 5 hours. After the loading was completed, the polypropylene fiber was filtered out, washed with deionized water, and dried to obtain polypropylene fiber loaded with nano-alumina. The loading rate of the polypropylene fiber loaded with nano-alumina was calculated to be 13.8% after weighing.

[0042] The third step is to mix 60 parts by weight of biomass ash residue with a particle size of 8-100 mesh after crushing, sieving, washing and drying with 12 parts by weight of cement, 6 parts by weight of quicklime, 0.6 parts by weight of polypropylene fiber loaded with nano alumina and 30 parts by weight of river sand with a particle size of 8-100 mesh to obtain a mixture.

[0043] Step 4: Add 12 parts by weight of water and 0.24 parts by weight of polycarboxylate superplasticizer to the mixture, stir and mix evenly to obtain the mixture. Pour the mixture into the mold, compact it, demold it and cure it to obtain a high-volume biomass ash brick.

[0044] A high-volume biomass ash brick is prepared by any of the above-mentioned preparation methods.

[0045] Application of a high-volume biomass ash brick, and its application in the building materials industry.

[0046] Comparative Example 1

[0047] The difference between this comparative example and Example 1 is that the polypropylene fibers are not modified; instead, unmodified polypropylene fibers loaded with nano-alumina are used directly.

[0048] A method for preparing high-volume biomass ash bricks includes the following steps:

[0049] Step 1: 10 parts by mass of nano-alumina, 1 part by mass of polyvinylpyrrolidone, and 89 parts by mass of deionized water were mixed and ultrasonically dispersed to obtain a nano-alumina suspension. Then, 1 part by mass of polypropylene fibers with a length of 8-12 mm was mixed into a three-necked flask equipped with a thermometer. Magnetic stirring was turned on, and the system temperature was controlled at 50℃ for 3 hours for loading. After loading, the polypropylene fibers were filtered out, washed with deionized water, and dried to obtain polypropylene fibers loaded with nano-alumina. The loading rate of the polypropylene fibers loaded with nano-alumina was calculated to be 0.11%.

[0050] The second step is to mix 50 parts by weight of biomass ash residue with a particle size of 8-100 mesh after crushing, sieving, washing and drying with 10 parts by weight of cement, 5 parts by weight of quicklime, 0.5 parts by weight of polypropylene fiber loaded with nano alumina and 25 parts by weight of river sand with a particle size of 8-100 mesh to obtain a mixture.

[0051] The third step is to add 10 parts by weight of water and 0.2 parts by weight of polycarboxylate superplasticizer to the mixture, stir and mix evenly to obtain the mixture, pour the mixture into the mold, compact it, demold it and cure it to obtain a high-volume biomass ash brick.

[0052] A high-volume biomass ash brick is prepared by any of the above-mentioned preparation methods.

[0053] Application of a high-volume biomass ash brick, and its application in the building materials industry.

[0054] Experimental Example

[0055] The compressive strength and flexural strength of the biomass ash brick specimens obtained in Examples 1-3 and Comparative Example 1 were tested according to the national standard GB / T 21144-2023 "Solid Concrete Bricks". The test results are shown in Table 1.

[0056]

[0057] As can be seen from Table 1, the biomass ash slag non-fired bricks in Examples 1 to 3 have better strength and toughness than the biomass ash slag non-fired bricks in Comparative Example 1. The ratio of compressive strength to flexural strength is close to 6:1, which is less than the ratio of 7:1 in Comparative Example 1. This indicates that the modified polypropylene fiber of the present invention can more effectively improve the toughness of biomass ash slag non-fired bricks.

[0058] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing biomass ash bricks with high admixture content, characterized in that, Includes the following steps: The biomass ash residue that has been crushed, sieved, washed and dried is mixed with cement, lime, polypropylene fiber loaded with nano-alumina and fine aggregate to obtain a mixture. Then water and water-reducing agent are added to the mixture and it is mixed again to obtain a blend. Finally, the blend is poured into a mold, compacted, demolded and cured to obtain a high-volume biomass ash residue brick. The polypropylene fiber is prepared by the following steps: Vinylphosphonochloride was loaded onto the surface of polypropylene fibers by irradiation grafting, followed by esterification with hydroxyethyl sulfonic acid to obtain modified polypropylene fibers. Finally, nano-alumina was loaded onto the surface of the modified polypropylene fibers to obtain polypropylene fibers loaded with nano-alumina.

2. The method for preparing a high-volume biomass ash brick according to claim 1, characterized in that, The particle size of the biomass ash residue after screening is 8-100 mesh.

3. The method for preparing a high-volume biomass ash brick according to claim 1, characterized in that, The lime is quicklime.

4. The method for preparing a high-volume biomass ash brick according to claim 1, characterized in that, The fine aggregate is river sand, with a particle size of 8-100 mesh.

5. The method for preparing a high-volume biomass ash brick according to claim 1, characterized in that, The water-reducing agent is a polycarboxylate water-reducing agent.

6. The method for preparing a high-volume biomass ash brick according to claim 1, characterized in that, The mass ratio of biomass ash, cement, lime, polypropylene fiber loaded with nano-alumina, fine aggregate, water, and water-reducing agent used is 50-60:10-12:5-6:0.5-0.6:25-30:10-12:0.2-0.

24.

7. The method for preparing a high-volume biomass ash brick according to claim 1, characterized in that, The polypropylene fiber has a length specification of 8-12 mm.

8. A high-volume biomass ash brick, obtained by the preparation method according to any one of claims 1 to 7.

9. An application of a high-volume biomass ash brick, specifically, the application of the high-volume biomass ash brick as described in claim 8 in the field of building materials.

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