|
| 微生物联合PAC对加固铀尾砂力学性能的影响研究 |
| Study on the influence of microbial combined with PAC on the mechanical properties of reinforced uranium tailings |
| 投稿时间：2024-03-09 修订日期：2024-03-29 |
| DOI： |
| 中文关键词: 微生物加固 PAC 固菌率 铀尾砂 |
| 英文关键词:Microbial reinforcement PAC Solid bacterial rate Uranium tailings |
| 基金项目:国家自然科学(52274167),湖南省技术攻关“揭榜挂帅”项目(2021SK1050),湖南省教育厅资助科研项目(22B0410),湖南省高新技术产业科技创新引领计划项目(2020SK2024),湖南省自然科学资助项目(2022JJ40374,2023J130516) |
|
| 摘要点击次数: 15 |
| 全文下载次数: 0 |
| 中文摘要: |
| 微生物诱导碳酸钙沉淀（MICP）技术是一项新型、环保的绿色加固技术，但是该技术却存在加固不均匀的难题。针对该问题，本文在铀尾砂中加入木质粉末活性炭（PAC），利用PAC的多孔结构和吸附性来延长细菌在试样中的滞留时间，提高固菌率，促进碳酸钙的增长和分布，使得加固更加均匀，进而提升尾砂样品的力学特性。利用无侧限抗压强度试验、碳酸钙生成量试验及固菌率试验，研究了活性炭含量对 MICP 加固铀尾砂的力学性能的影响，试验结果表明，铀尾砂中加入PAC能够提高MICP反应过程中碳酸钙的生成量，并且在1.5%PAC时碳酸钙生成量达到最大值，随着PAC含量的增加，尾砂试样的峰值应力先增加后减小，在PAC含量为1.5%时尾砂试样峰值应力达到最大，无侧限抗压强度试验的峰值应力为2072kPa，是未添加PAC试样强度的1.53~1.76倍，加入PAC后砂柱的破坏形式依旧是弹性变形，在到达应力峰值后发生脆性破坏，0.0%PAC的试样发生的是局部破坏，0.75%PAC试样发生的是剪切破坏，部分区域发生局部破坏，而在1.5%PAC时的试样应力达到峰值，发生劈裂式破坏。 |
| 英文摘要: |
| Microbial induced calcium carbonate precipitation (MICP) technology is a new and environmentally friendly green reinforcement technology, but it faces the problem of uneven reinforcement. In response to this issue, this article adds wooden powder activated carbon (PAC) to uranium tailings, utilizing the porous structure and adsorption properties of PAC to prolong the retention time of bacteria in the sample, improve the bacterial fixation rate, promote the growth and distribution of calcium carbonate, make reinforcement more uniform, and thereby improve the mechanical properties of tailings samples. The influence of activated carbon content on the mechanical properties of uranium tailings reinforced with MICP was studied using unconfined compressive strength test, calcium carbonate generation test, and bacterial retention rate test. The test results showed that the addition of PAC to uranium tailings can increase the amount of calcium carbonate generated during the MICP reaction process, and the amount of calcium carbonate generated reaches its maximum value at 1.5% PAC. With the increase of PAC content, the peak stress of the tailings sample first increases and then decreases, When the PAC content is 1.5%, the peak stress of the tailings sample reaches its maximum. The peak stress of the unconfined compressive strength test is 2072kPa, which is 1.53-1.76 times the strength of the sample without PAC added. After adding PAC, the failure mode of the sand column is still elastic deformation, and brittle failure occurs after reaching the stress peak. The sample with 0.0% PAC experiences local failure, the sample with 0.75% PAC experiences shear failure, and some areas experience local failure, At 1.5% PAC, the stress of the sample reached its peak and a splitting failure occurred. |
| 查看/发表评论 下载PDF阅读器 |
| 关闭 |
|
|
|