img

Wechat

Adv. Search

Gold Science and Technology ›› 2019, Vol. 27 ›› Issue (6): 912-919.doi: 10.11872/j.issn.1005-2518.2019.06.912

• Mining Technology and Mine Management • Previous Articles     Next Articles

Study on Cementation Filling Test and Environmental Effect of Gold Mine Tailings

Zhu SU(),Deming ZHANG,Qinli ZHANG()   

  1. School of Resources and Safety Engineering,Central South University,Changsha 410083,Hunan,China
  • Received:2019-05-06 Revised:2019-06-19 Online:2019-12-31 Published:2019-12-24
  • Contact: Qinli ZHANG E-mail:346374304@qq.com;zhangqinlicn@126.com

Abstract:

The total amount of gold produced in China is among the highest in the world,and the massive mining of gold has led to a large accumulation of gold mine tailings.There are a lot of toxic and harmful heavy metals in gold mine tailings.How to deal with gold mine tailings in a safe and environmentally friendly way is a very intractable problem at present.Recycling gold mine tailings as cemented paste backfill(CPB) filling into the mine as support is currently a popular method to solve the problem.In order to explore the compressive strength and environmental effects of gold mine tailings after being recycled as CPB,the cementing ratio test,heavy metal leaching and solidification test of gold tailings was carried out.In the cementing ratio test,12 groups of samples were prepared,the cement-tailings ratio was 1∶6,1∶8,1∶12,1∶20,and the mass concentration was 77%,75%,73%.After a period of maintenance,the uniaxial compressive strength for 7 days,12 days and 28 days of 12 sets of test pieces were tested respectively.Finally,the optimum cementing ratio parameters were determined on the premise of considering the strength requirements of mining technology support and the economic cost of filling comprehensively.Heavy metal leaching test was carried out in two groups:48 hours leaching test of filling slurry and dynamic leaching test of CPB.The two sets of experiments were used to simulate the short-term leaching of the filled slurry and the long-term leaching of the CPB,and the purpose was to explore the environmental effects and potential pollution elements of the gold mine tailings after being recycled as CPB.After the heavy metal elements with potential contamination risks are identified by the leaching test,the corresponding curing agent was selected to carry out the curing test of heavy metals.The leaching of potentially polluting elements was tested again by adding different concentration of solidifying agent,and the concentration of solidifying agent which could eliminate the pollution risk of heavy metals leaching from CPB to groundwater was finally determined.Based on the above experiments,a safe and environmentally friendly method for recovering gold tailings is finally determined.The results show that The optimum cementation ratio of the gold tailings is 1∶8 for the cement-tailings ratio and 75% for the mass concentration.The leaching of harmful elements in the tailings can be effectively controlled after the gold tailings are recovered as CPB,which reduces the pollution to the environment.The As leached from CPB has potential pollution risk to groundwater,adding 3% FeCl3 to CPB can effectively avoid the pollution.

Key words: cementing ratio, compressive strength, leaching contrast, dynamic leaching, contaminated elements, heavy metal solidification

CLC Number: 

  • X5

Fig.1

Grain size distribution map of unclassified tailings"

Table 1

Physical and mechanical properties of unclassified tailings"

参数数值参数数值
比重/(t·m-3)2.73水上休止角/(°)37.5
渗透系数/(cm·s-12.56×10-5水下休止角/(°)29.0

Table 2

Composition of mineral components of unclassified tailings(%)"

成分质量分数成分质量分数
石英30.04叶腊石3.44
黄铁矿7.41石膏0.87
云母8.35长石12.63
高岭石37.26

Fig.2

Unconfined compressive strength evolution with different cement/tailings ratios and slurry concentrations"

Fig.3

Change in chemical properties of unclassified tailings leachate and backfill samples leachate in 48 hours"

Table 3

Comparison of leaching amount of metal elements in gold unclassified tailings and backfill samples(mg·kg-1)"

元素沥滤液中各元素含量尾砂各元素总含量
金矿尾砂充填混合样品
Ni2.30.19.23
Cu1.60.2100.76
Pb0.2-19
Cd--0.12
Zn0.80.119.78
Co0.4-6.12
As6.60.327.13

Fig.4

pH value of the leachate in five-round dynamic leaching of unclassified tailings and filling blocks with different solidification ages"

Table 4

The concentration of metals in the leaching solution after dynamic leaching of gold unclassified tailings and backfill samples"

样本元素质量浓度/(mg·L-1
NiCuPbCdZnCoAs
金矿全尾砂0.040.50.01<0.00010.030.030.3
7 d固化试块0.0080.0020.001<0.00010.0020.0010.01
14 d固化试块0.004<0.0010.001<0.00010.002<0.00090.005
28 d固化试块0.001<0.001<0.001<0.00010.001<0.00090.001
国家标准Ⅲ类标准0.021.000.010.0051.000.050.01

Fig.5

Effect of FeCl3 addition on As concentration in secreted water during filling"

Fig.6

Relationship between As leaching concentration and eaching time under different concentrations of FeCl3"

1 刘应冬,代力,张卫华.青海某金矿矿集区土壤重金属污染评价及综合利用讨论[J].矿产综合利用,2018(5):97-100.
Liu Yingdong,Dai Li,Zhang Weihua.Assessment of soil heavy metals pollution and comprehensive utilization in a gold mine area in Qinghai[J].Multipurpose Utilization of Mineral Resources,2018(5):97-100.
2 汤波,赵晓光,冯海涛,等.陕南某铅锌尾矿区土壤重金属迁移性及生态风险评价[J].江苏农业科学,2016,45(5):465-468.
Tang Bo,Zhao Xiaoguang,Feng Haitao,et al.Mobility and ecological risk of heavy metals in soils around lead-zinc mine tailings in southern Shaanxi[J].Jiangsu Agricultural Sciences,2016,45(5):465-468.
3 Li X B,Du J,Gao L,et al.Immobilization of phosphogypsum for cemented paste backfill and its environmental effect[J].Journal of Cleaner Production,2017,156:137-146.
4 马明辉,谭云亮,朱明德.三山岛金矿充填材料配比与强度试验[J].有色金属工程,2015,5(6):60-63.
Ma Minghui,Tan Yunliang,Zhu Mingde,Filling materials strength test with various ratio in Sanshandao gold mine[J].Nonferrous Metal Engineering,2015,5(6):60-63.
5 赵彬.焦家金矿尾砂固结材料配比试验及工艺改造方案研究[D].长沙:中南大学,2009.
Zhao Bin.Study of Tailing-cemented Materials Proportion and Backfilling Technology Transformation[D].Changsha:Central South University,2009.
6 郭勋英,曹芳杰,阙永航.金矿尾矿的开发与利用——以山东招远界河金矿床为例[J].西部探矿工程,2014,26(5):133-136,140.
Guo Xunying,Cao Fangjie, Que Yonghang.Development and utilization of gold tailings:Taking Zhaoyuan Jiehe gold deposit in Shandong Province as an example[J].West-China Exploration Engineering,2014,26(5):133-136,140.
7 曾理,吴永贵,苏连文,等.金矿尾矿废水及废渣浸出液的理化特征及生物毒性效应[J].贵州农业科学,2010,38(5):227-229.
Zeng Li,Wu Yonggui,Su Lianwen,et al.Physical-chemical properties and biological toxic effect of wastewater and sludge leachate in gold mine tailing[J].Guizhou Agricultural Science,2010,38(5):227-229.
8 张蕊.金矿尾矿场周边土壤与植被重金属污染现状研究[D].西安:西安科技大学,2011.
Zhang Rui.The Study of Heavy Metal Pollution of Soil and Vegetation Around Gold Mine Tailings [D].Xi’an:Xi’an University of Science and Technology,2011.
9 黄远来.磷尾矿胶结充填添加剂减阻输送及有害离子固化试验研究[D].贵阳:贵州大学,2017.
Huang Yuanlai.Experimental Study on Using Additives for Drag Reduction and Harmful Ion Curing in Phosphate Tailings Cemented Filling[D].Guiyang:Guizhou University,2017.
10 樊浩伦.水泥固化锌污染红粘土力学性能及固化机理研究[D].呼和浩特:内蒙古农业大学,2017.
Fan Haolun.Study on Mechanical Properties and Curing Mechanism of Solidified/Stabilized of Zn-contaminated Red Clay[D].Hohhot:Inner Mongolia Agricultural University,2017.
11 吴万富.强化絮凝沉淀法治理砷污染天然水体及絮凝浮选法处理高砷废水的研究[D].昆明:云南大学,2016.
Wu Wanfu.Research on the Treatment of Arsenic Pollution in Natural Water by Enhanced Flocculation Sedimentation and High Arsenic Wastewater by Flocculation Flotation [D].Kunming:Yunnan University,2016.
12 Laky D,Licsko I.Arsenic removal by ferric-chloride coagulation-effect of phosphate,bicarbonate and silicate[J].Water Science and Technology,2011,64(5):1046-1055.
13 Qiao J L,Jiang Z,Sun B,et al.Arsenate and arsenite removal by FeCl3:Effects of pH,As/Fe ratio,initial As concentration and coexisting solutes [J].Separation and Purification Technology,2012,92(1):l06-114.
14 王新民,肖卫国,张钦礼.深井矿山充填理论与技术[M].长沙:中南大学出版社,2005.
Wang Xinmin,Xiao Weiguo,Zhang Qinli.Filling Theory and Technology in Deep Mines [M].Changsha:Central South University Press,2005.
15 周爱民,古德生.基于工业生态学的矿山充填模式[J].中南大学学报(自然科学版),2004,35(3):468-472.
Zhou Aimin,Gu Desheng.Mine-filling model based on industrial ecology[J].Journal of Central South University of Technology(Sciences and Technology),2004,35(3):468-472.
16 何军志,赵国燕.利用水泥固化废弃物减少有害金属离子溶出的试验探索[J].实验技术与管理,2012,29(9):36-39.
He Junzhi,Zhao Guoyan.Use of cement curing a variety of industrial waste reduction of underground water pollution[J].Experimental Technology and Management,2012,29(9):36-39.
17 郑继东,李东艳,胡斌,等.煤矸石矿井充填对地下水环境影响的模拟实验[J].矿业研究与开发,2007,27(1):76-78.
Zheng Jidong,Li Dongyan,Hu Bin,et al.Simulation experiments on the impact of Gangue filled in mined-out area on underground water environment[J].Mining Research and Development,2007,27(1):76-78.
18 Bissen M,Frimmel F H.Arsenic-A review.Part Ⅱ:Oxidation of arsenic and its removal in water treatment[J].Acta Hydrochimica et Hydrobiologica,2003,31(2):97-107.
19 Streat M,Hellgardt K,Newton N L R.Hydrous fenrric oxide as an adsorbent in water treatment:Part 2.Adsorption studies[J].Process Safety and Environmental Protection,2008,86(1):11-20.
20 Mohan D,Pittman C U.Arsenic removal from water/wastewater using adsorbents-A critical review[J].Journal of Hazardous Materials,2007,142(1/2):1-53.
[1] Wenfeng XIAO,Jianhong CHEN,Yi CHEN,Ximei WANG. Optimization of Multi-objective Filling Slurry Ratio Based on Neural Network and Genetic Algorithm [J]. Gold Science and Technology, 2019, 27(4): 581-588.
[2] CHENG Hao, XU Tao, ZHOU Guanglei, FANG Ke. Numerical Simulation of Fracture and Acoustic Emission Evolution of Hetero-geneous Rocks [J]. Gold Science and Technology, 2018, 26(2): 170-178.
[3] WANG Jin,GONG Fengqiang. Study On Rate Effect of Uniaxial Compression Test for Red Sandstone [J]. Gold Science and Technology, 2018, 26(1): 56-63.
[4] LAN Zhipeng,WANG Xinmin,WANG Hongjiang,CHEN Qiusong. Experiment Research on Slurry Setting Time’s Effect on High-sulphur Backfill’s Compressive Strength [J]. Gold Science and Technology, 2016, 24(5): 13-18.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
No Suggested Reading articles found!