摘要
为缓解深井开采高温热害,探明聚氯乙烯(PVC)充填体的隔热性能,对PVC粉末替代水泥掺量为0~20%的充填体进行热重、导热系数、比热容测试及其微观形貌特征分析。结果表明:添加PVC粉末能改善充填体的隔热性能;PVC颗粒与充填体结合形成致密均匀的结构,但由于PVC的弱黏结性,过量的PVC粉末会使充填体各成分之间的黏结性丧失,内部孔隙和裂纹增多,降低充填体的抗压强度,且抗压强度随PVC粉末含量添加呈先增大后减小的趋势。在料浆质量浓度78%、灰砂比1∶4和PVC粉末替代水泥掺量为10%的条件下,充填体性能最佳,此时抗压强度最大,为10.782 MPa,导热系数为0.921 W/(m·K)且降幅最大,比热容则为1.391 kJ/(kg·K)。本文分析了PVC粉末充填体的热学性能,为缓解深井开采热害提供新思路。
In order to alleviate the heat damage caused by high temperature in deep wells and explore the thermal insulation performance of the polyvinyl chloride(PVC)backfill,thermogravimetry,thermal conductivity,specific heat capacity and micro−morphology of the backfill with 0%~20%PVC powder were measured.The results showed that adding PVC powder can improve the thermal insulation performance of the backfill;PVC particles were combined with the backfill to form a dense and uniform structure.However,due to the weak adhesion of PVC,excessive PVC powder could lead to a loss of adhesion between the components of the backfill,an increase in internal pores and cracks,and a decrease in the compressive strength of the backfill.The compressive strength showed a trend of first increasing and then decreasing with the content of PVC powder.Under the conditions of a slurry mass concentration of 78%,a cement to sand ratio of 1∶4,and a PVC powder replacement cement content of 10%,the backfill had the best performance.At that time,the compressive strength was the highest,at 10.782 MPa,the thermal conductivity was 0.921 W/(m·K),and the decrease was the largest.The specific heat capacity was 1.391 kJ/(kg·K).This article analyzed the thermal properties of PVC powder backfill,providing new ideas for alleviating thermal hazards in deep well mining.
作者
李婷婷
郭进平
王小林
刘亚雄
侯展娜
吴琼
LI Tingting;GUO Jinping;WANG Xiaolin;LIU Yaxiong;HOU Zhanna;WU Qiong(School of Resources Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,Shaanxi,China;Henan Fender Mining Co.,LTD,Luoyang 471000,Henan,China)
出处
《矿产保护与利用》
2025年第1期1-7,共7页
Conservation and Utilization of Mineral Resources
基金
陕西省自然科学基金项目(2024JC-YBQN-0507)
国家资助博士后研究人员计划项目(GZC20232063)
陕西省博士后科研项目(2023BSHYDZZ142)。
关键词
深井开采热害
PVC粉末充填体
热学性能
隔热性能
导热系数
deep well heat damage
PVC powder
thermal performance
thermal insulation performance
thermal conductivity
