ERI: Mechanism for Improved Strength in Fast Pyrolysis Biochar Concrete

ERI：提高快速热解生物炭混凝土强度的机制

• 批准号: 2139035
• 负责人: Lori Tunstall
• 金额: $ 20万
• 依托单位: Colorado School of Mines
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2139035&HistoricalAwards=false
• 关键词: ERI; Mechanism; Improved; Strength; Fast

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). This Engineering Research Initiation (ERI) project will focus on elucidating the mechanisms that lead to improved strength in fast pyrolysis biochar concrete. Biochar is a carbon-rich material made from the pyrolysis of biomass. Biochar is produced via the thermal decomposition of biomass in a zero or limited oxygen environment. Since biochar is highly stable, the embedded carbon is resistant to decomposition, slowly releasing CO2 over hundreds or thousands of years. This results in long-term removal of carbon from the atmosphere, making biochar a powerful material for carbon sequestration. Fast pyrolysis of biomass generates also a bio-oil and synthetic natural gas, which can generate energy and decrease the use of fossil fuels. Recently, biochar has gained momentum as a carbon sequestering agent for use in concrete. However, this application has only utilized slow pyrolysis biochar, which has much different properties than the fast pyrolysis biochar adopted in this project. By using fast pyrolysis biochar, a preliminary study shows that when 15 percent of cement weight is replaced with biochar, the strength of concrete increases by nearly 40 percent. At 15 percent biochar to cement substitution, the biochar can offset the greenhouse gas emissions associated with concrete by at least 48 percent; at 32 percent biochar to cement substitution, the biochar would make concrete a carbon negative building material. To accomplish this goal, three primary objectives are identified: 1) to characterize the microstructural and physiochemical properties of three distinct fast pyrolysis biochar products; 2) to characterize the microstructure and chemical composition of cementitious materials made with these three biochar products; and 3) to analyze the strength behavior of the resulting concretes and the strength-microstructure relationship. Furthermore, this award contributes to the education of a female graduate student, and will provide research opportunities for middle school girls with events designed to address the reported gap between STEM interest/aptitude in adolescent girls and girls’ chosen career paths at later ages.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该奖项全部或部分由《2021 年美国救援计划法案》（公法 117-2）资助。该工程研究启动 (ERI) 项目将重点阐明提高快速热解生物炭混凝土强度的机制。生物炭是由生物质热解制成的富含碳的材料，生物炭是通过生物质在零氧或有限氧气环境中的热分解而产生的。嵌入的碳稳定，不易分解，可在数百或数千年的时间内缓慢释放二氧化碳，从而长期去除大气中的碳，使生物炭成为碳封存的强大材料，生物质的快速热解也产生生物。 - 石油和合成天然气，可以产生能源并减少化石燃料的使用，最近，生物炭作为碳封存剂在混凝土中的应用得到了发展，但该应用仅利用了缓慢热解的生物炭。与本项目采用的快速热解生物炭的性能有很大不同，初步研究表明，当用生物炭代替15%的水泥重量时，混凝土的强度增加了近40%。如果用生物炭替代水泥，则可以抵消至少 48% 的混凝土相关温室气体排放；如果用生物炭替代水泥，生物炭可以使混凝土成为负碳建筑材料。确定了三个主要目标：1）表征三种不同的快速热解生物炭产品的微观结构和物理化学特性；2）表征用这三种生物炭产品制成的水泥材料的微观结构和化学成分；3）分析强度行为。此外，该奖项有助于女研究生的教育，并将通过旨在解决青少年 STEM 兴趣/能力之间报告差距的活动，为中学生提供研究机会。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。