摘要
为解决金英金矿外购铁矿尾砂在寒冷气候条件下充填存在充填体强度低、稳定性差以及井下产出废石大量堆积的难题,开展废石破碎用于井下充填的室内实验。研究结果表明:在充填倍线为2.0~6.0的前提下,废石充填料浆质量分数可达75%以上;当废石与尾砂的质量比为3~6时,对充填料浆流动性和充填体强度无明显影响;粒径d≤5 mm废石+压滤尾砂的充填骨料可获得最大充填体强度,充填骨料的充填体强度从大到小依次为d≤5 mm废石、d≤8 mm废石+压滤尾砂、d≤5 mm废石+铁矿尾砂、铁矿尾砂和d≤8 mm废石+铁矿尾砂;料浆质量分数是确保充填体强度和降低水泥掺量的关键,采用d≤5 mm废石+水泥充填时,料浆质量分数每提高1%,水泥掺量可降低1.2%;当养护温度由10℃提升至15℃时,充填体充填时间为7 d及28 d强度分别提高109.52%和58.46%;经现场工业试验,推荐采用的d≤5 mm废石胶结充填料浆实际质量分数为75%,水泥掺量为11%,充填能力为110 m^3/h,充填成本降低15%~18%。
In order to solve the problems of out-sourced backfilling material in Jinying gold deposit under cold weather, such as low strength of backfilling, poor stability and accumulation of waste rock produced underground, a lab experiment was conducted using crushed waste rock for underground backfill. The results show that when the stowing gradient is 2.0-6.0, the mass fraction of waste backfill slurry can reach above 75%. When the mix ratio of crushed waste to tailings is 3-6, it has no significant effect on backfill slurry fluidity or backfill strength. The filling slurry with waste rock ofd≤5 mm ＋ pressed tailings obtains the maximum backfill strength, and other types of slurry have lower strength, so the strength levels are the crushed waste rock of d≤ 5 mm, waste rock of d≤ 8mm ＋ pressed tailings, waste rock of d ≤ 5 mm ＋ iron railings, iron tailings and waste rock of d≤ 8 mm ＋ iron tailings in turn from high level to low level. Slurry density is the key factor for backfill strength and for reducing cement dosage. When the waste rock of d≤ 5 mm ＋ cement is used for backfill, every 1% increase of slurry mass fraction can reduce 1.2% of cement dosage. When the curing temperature rises from 10 ℃ to 15 ℃, the backfill time of 7 d and 28 d backfill strength increase 109.52% and 58.46%, respectively. After the field industrial tests, it is recommended to the backfill with d≤5 mm waste rock cemented slurry with a mass fraction of 75% and cement dosage of 11%. The backfill capacity can reach 110 m3/h, and the cost of backfilling can be reduced by 15%-18%.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2015年第11期4195-4203,共9页
Journal of Central South University:Science and Technology
基金
国家"十二五"科技支撑计划项目(2012BAB08B02)
新世纪优秀人才支持计划项目(NECT-13-0669)
国家自然科学基金资助项目(50774011)~~
关键词
废石胶结充填
寒冷气候
配比优化
工业试验
waste rock cementing backfill
extreme cold weather
mix ratio optimization
industrial experiment
