KR-20260063181-A - Multifunctional cement composite composition with plant-based biochar added

Abstract

The present invention relates to a multifunctional cement composite composition containing plant-based biochar. By replacing a portion of the cement with plant-based biochar, the invention reduces carbon emissions from the cement composite, decreases the environmental impact of the construction industry, improves economic efficiency through lower costs compared to conventional cement, contributes to cost reduction and environmental protection through the recycling of waste materials, and enhances the durability and mechanical performance of the cement composite. The multifunctional cement composite composition with added plant-based biochar according to the present invention substitutes 4 to 12 weight percent of biochar made from coconut shells based on 100 weight percent of cement. In addition, 12 to 17 weight parts of one or more of blast furnace slag and silica fume are added as strength reinforcing agents to 100 weight parts of the multifunctional cement composite composition with added plant-based biochar.

Inventors

• 이희영
• 강선호
• 차인영

Assignees

• 조선대학교산학협력단

Dates

Publication Date

20260507

Application Date

20241030

Claims (6)

1. A multifunctional cement composite composition containing plant-based biochar, characterized by substituting 4 to 12 weight percent of biochar made from coconut shells based on 100 weight percent of cement.
2. A multifunctional cement composite composition containing plant-based biochar according to claim 1, characterized in that the biochar is produced through a first step of crushing coconut shells, a second step of producing biochar by pyrolyzing and cooling the coconut shells crushed in the first step, and a third step of producing fine biochar by crushing the biochar produced through the second step to use as a cement substitute.
3. A multifunctional cement composite composition with added plant-based biochar, characterized in that, in claim 2, the second step comprises a pyrolysis step of heating coconut shell powder at a temperature of 630 to 670°C for 3 hours 40 minutes to 4 hours 20 minutes, and a cooling step of cooling the coconut shell powder that has undergone the pyrolysis step to produce biochar.
4. A multifunctional cement composite composition containing plant-based biochar, characterized in that, in any one of claims 1 to 3, a strength reinforcing agent is added to increase the compressive strength of the biochar, which is generally lowered.
5. A multifunctional cement composite composition with added plant-based biochar according to claim 4, characterized in that 12 to 17 parts by weight of one or more of blast furnace slag and silica fume are added as strength reinforcing agents to 100 parts by weight of the multifunctional cement composite composition with added plant-based biochar.
6. A multifunctional cement composite composition with added plant-based biochar, characterized in that, in claim 1, 90 to 110 parts by weight of sand are mixed with 100 parts by weight of the mixture of cement and biochar.

Description

Multifunctional cement composite composition with plant-based biochar added The present invention relates to a cement composite, and more specifically, to a multifunctional cement composite composition containing plant-based biochar that reduces cement usage by replacing cement with an eco-friendly material. Globally, carbon dioxide ( Interest and efforts to reduce emissions are more active than ever before. In particular, the construction industry, with its massive amounts of various processes It is a major sector where it occurs, and among them, the cement production process is the most It is recognized as a significant problem in that it emits... As cement is the main raw material for concrete, the... generated during cement production is total It accounts for approximately 5–10% of emissions. Cement production is continuously increasing as the demand for cement grows and urbanization accelerates. In Korea, approximately 51.06 million tons of cement were produced in 2022, reaching the 12th position globally. As the cement industry is expected to expand further in the future, the development of technologies to reduce carbon emissions during the cement production process is emerging as a critical issue. Regarding patent documents related to the present invention, Registered Patent No. 10-2675583 describes the use of blast furnace slag fine powder and biochar powder (generated by the thermal decomposition of biomass generated from wood pellet power plants) mixed into mortar; Published Patent No. 10-2023-0154258 describes a cement composition comprising cement, biochar, and a hydrophobic agent; and Published Patent No. 10-2024-0145572 describes the substitution of biochar (woody) as a cement admixture. While these are technologies that utilize plant-based materials as cement substitutes, they do not include a technology to resolve the reduction in strength caused by the addition of biochar. FIG. 1 is a graph of the 7-day and 28-day compressive strength of biochar-mixed cement as a test result of a multifunctional cement composite composition with added plant-based biochar according to the present invention. FIG. 2 is a graph of the 7-day and 28-day compressive strength of biochar and blast furnace slag-mixed cement as a test result of a multifunctional cement composite composition with added plant-based biochar according to the present invention. Figure 3 is a graph of the 7-day and 28-day compressive strength of biochar and silica fume-mixed cement as a test result of a multifunctional cement composite composition with added plant-based biochar according to the present invention. Figure 4 is a graph showing the difference in 28-day compressive strength between biochar-mixed cement, biochar and blast furnace slag-mixed cement, biochar-mixed cement, and biochar and silica fume-mixed cement, as test results of a multifunctional cement composite composition with added plant-based biochar according to the present invention. In the following description of the present invention, specific descriptions of related known functions or configurations will be omitted if it is determined that such descriptions would unnecessarily obscure the essence of the invention. Furthermore, the terms described below are defined in consideration of their functions within the present invention, and these definitions may vary depending on the intentions or practices of the user or operator. Therefore, such definitions should be based on the content throughout this specification. As shown in FIG. 1, the multifunctional cement composite composition with added plant-based biochar according to the present invention replaces cement with biochar, and the biochar replaces 4 to 12 weight percent based on 100 weight percent of cement, that is, the composition consists of a mixture of 88 to 96 weight percent of cement and 4 to 12 weight percent of biochar substitute based on 100 weight percent of the total cement composite composition. In the present invention, biochar is produced from coconut shells, and the background is as follows. 250 million tons of coconut shells are discarded annually, causing land pollution and global warming. Recycling these discarded coconut shells into biochar allows them to be utilized as high-value-added products due to their excellent properties. Biochar is a carbon-based material produced by the thermal decomposition of biomass in a high-temperature, oxygen-free environment and contains numerous fine internal pores. These micropores can effectively absorb and retain moisture within cement composites, thereby regulating the hydration reaction of the cement to suppress cracking, improve long-term durability, and help mitigate the urban heat island effect. Based on this background, biochar produced from coconut shells is used as a cement substitute to partially replace cement. In addition, the manufacturing process of biochar according to the present invention is as follows. 1. Crush the coconut shell. Coconut shell