浸泡淋滤作用下煤矸石重金属元素的释放规律及特征研究

康得军; 张芳; 吕茳芏; 龚亚萍; 赵颖; 脱向银

doi:10.13198/j.issn.1001-6929.2022.11.18

浸泡淋滤作用下煤矸石重金属元素的释放规律及特征研究

doi: 10.13198/j.issn.1001-6929.2022.11.18

康得军^{1, 2, 3,},
张芳²,
吕茳芏³,
龚亚萍¹,
赵颖^1, ,,
脱向银⁴

1.
中国环境科学研究院水生态环境研究所，北京　100012
2.
福州大学先进制造学院，福建晋江　362251
3.
福州大学土木工程学院，福建福州　350108
4.
宁夏远声绿阳林草生态工程有限公司，宁夏银川　750000

基金项目: 国家重点研发计划项目(No.2019YFC1903901, 2019YFC1904301)

详细信息

作者简介:
康得军（1981-），男，湖北十堰人，副教授，博士，主要从事固废资源化利用研究，djkang@fzu.edu.cn

通讯作者:
赵颖(1981-)，女，黑龙江哈尔滨人，研究员，博士，主要从事环境净化材料研发及固废资源化技术研究，zhaoyhky@163.com

中图分类号: X53
计量
- 文章访问数: 254
- HTML全文浏览量: 93
- PDF下载量: 86
- 被引次数: 0
出版历程
- 收稿日期: 2022-07-19
- 修回日期: 2022-11-21

Research on Release Law and Characteristics of Heavy Metals in Coal Gangue under Soaking and Leaching

KANG Dejun^{1, 2, 3
,},
ZHANG Fang²,
LÜ Jiangdu³,
GONG Yaping¹,
ZHAO Ying^{1
, ,},
TUO Xiangyin⁴

1.
Institute of Water Ecology and Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
2.
College of Advanced Manufacturing, Fuzhou University, Jinjiang 362251, China
3.
College of Civil Engineering, Fuzhou University, Fuzhou 350108, China
4.
Ningxia Yuansheng Lvyang Forest & Grass Ecological Engineering Co., Ltd., Yinchuan 750000, China

Funds: National Key Research and Development Program of China (No.2019YFC1903901, 2019YFC1904301)

摘要

摘要: 为探究天然煤矸石在雨水浸泡淋滤作用下重金属元素的释放规律及特征，通过扫描电镜(SEM)对天然煤矸石进行表征以观察其淋滤前后的微观形貌，借助X射线衍射(XRD)技术测定煤矸石淋滤前后的矿物成分组成及变化情况. 结合模拟降水连续静态浸泡与动态淋滤试验，考察在不同固液比、粒径、pH、土壤介质条件下煤矸石中重金属元素的释放规律与特性. 结果表明：①淋滤后的煤矸石表面凹凸结构较多，淋滤前后煤矸石中各矿物相含量差异较小. ②As、Mn的浸出浓度均较高，最大释放率大小表现为As>Cd>Cu≈Ni>Mn>Cr>Zn>Pb. As的累积释放对周边土壤环境以及地下水产生不利影响的风险较高. ③连续动态淋滤试验在pH为3时，Mn、Cu、Zn、Ni的累积释放量明显较高，As、Cr在中性条件下的累积释放量高于在酸性条件下. 引入土壤介质这一因素后，Cr、As的累积释放量均明显减少，这两种重金属元素均呈现出在土壤中积累的状态. 研究显示：对于相同煤矸石堆存量，降雨量越大，重金属的释放总量越高，固液比为1∶20时，As释放量最高可达2.822 μg/L；Cr、As呈现出在土壤中积累的状态，煤矸石淋滤后Cr、As对土壤存在潜在污染风险，同时也需考虑其对周边地下水的影响.
- 煤矸石 /
- 重金属元素 /
- 释放规律 /
- 淋滤 /
- 影响因素
Abstract: In order to explore the release law and characteristics of heavy metals in natural coal gangue under the rainwater soaking and leaching, scanning electron microscope (SEM) was used to observe the microscopic morphology of natural coal gangue and X-ray diffraction (XRD) was used to determine the mineral composition and changes before and after leaching. The release law and characteristics of heavy metals in coal gangue were investigated by continuous static soaking and dynamic leaching tests with simulated precipitation under different solid-liquid ratio, particle size, pH and soil medium conditions. The results show that: (1) SEM and XRD analysis results reveal that the surface of natural coal gangue has a layered structure with high smoothness, and after leaching, the surface of coal gangue presents more concave-convex structures. There is small change in the content of each mineral phase, therefore the coal gangue has high stability during natural rainfall leaching process. (2) The simulated continuous static soaking test shows that the leaching content of As and Mn is higher, and the release rates are ranked as As>Cd>Cu≈Ni>Mn>Cr>Zn>Pb. Among them, the cumulative release of As poses a higher risk of adverse effects on the surrounding soil environment and groundwater, and the leaching of Cu has two stages: rapid release and stable release. Zn, Pb, and Cd belong to the late-stage release elements; Cr and As belong to indirect release elements; Mn belongs to fast release elements; and Ni belongs to slow release elements. (3) The continuous dynamic leaching test shows that the cumulative release of Mn, Cu, Zn and Ni is significantly higher at pH 3.0, and the cumulative release of As and Cr under neutral conditions is higher than that under acidic conditions. After the introduction of the soil medium, the cumulative release of Cr and As decreased significantly, indicating that both heavy metals are adsorbed the soil. The research shows that for the same stack of coal gangue, the release of heavy metals is higher with high rainfall. The maximum release of As can reach 2.822 μg/L at a solid-liquid ratio of 1∶20. Because Cr and As are accumulated in the soil, after leaching of the coal gangue, Cr and As pose potential risk of polluting the soil, and the impact on surrounding groundwater should also be considered.
- coal gangue /
- heavy metal ions /
- release law /
- leaching /
- influencing factors

HTML全文

图 1 煤矸石动态淋滤试验装置

Figure 1. Coal gangue dynamic leaching test device

下载: 全尺寸图片幻灯片

图 2 天然煤矸石淋滤前后形貌

Figure 2. Morphology of natural coal gangue before and after leaching

下载: 全尺寸图片幻灯片

图 3 天然煤矸石淋滤前后XRD图谱

Figure 3. XRD patterns of natural coal gangue before and after leaching

下载: 全尺寸图片幻灯片

图 4 不同固液比条件下煤矸石浸泡液中重金属浸出浓度曲线

Figure 4. Curve of heavy metal leaching concentration of coal gangue immersion solution under different solid-liquid ratios

下载: 全尺寸图片幻灯片

图 5 不同粒径煤矸石浸泡液中重金属浸出浓度曲线

Figure 5. Heavy metal leaching curves of coal gangue immersion solution with different particle sizes

下载: 全尺寸图片幻灯片

图 6 不同pH淋滤液淋滤下煤矸石浸泡液中重金属浸出浓度曲线

Figure 6. Leaching concentration curve of heavy metals in coal gangue leaching solution under different pH leachate

下载: 全尺寸图片幻灯片

图 7 不同土壤介质下煤矸石浸泡液中重金属浸出浓度曲线

Figure 7. Heavy metal release curves of leachate under different soil media

下载: 全尺寸图片幻灯片

表 1 宁夏银川市宁东镇某矿区重金属含量土壤背景值

Table 1. Soil background value of heavy metal content in a mining area of Ningdong Town, Yinchuan City, Ningxia

项目	含量/(mg/kg)
项目	Cu	Zn	Pb	Cr	Cd	As	Mn	Ni
煤矸石样品	25.08	109.03	24.76	44.81	0.256	16.73	293.46	22.58
原土	12.87	105.46	16.17	116.61	0.089	12.97	423.76	22.70
对照点土壤背景值	12.61	101.72	17.53	91.88	0.098	10.73	392.23	21.20
银川市土壤背景值(平均值)	19	52	19	61	0.12	11	490	25
农用地土壤污染风险筛选值¹⁾	100	300	170	200	0.6	25	—	190
注：1)农用地土壤污染风险筛选值引自《土壤环境质量农用地土壤污染风险管控标准(试行)》(GB 15618—2018).

下载: 导出CSV

表 2 煤矸石连续浸泡试验条件

Table 2. Experimental conditions for continuous soaking of coal gangue

条件	固液比	粒径	pH
试验组Ⅰ	1∶10	0.15~0.5 mm	7±0.3
试验组Ⅱ	1∶05	0.15~0.5 mm	7±0.3
试验组Ⅲ	1∶20	0.15~0.5 mm	7±0.3
试验组Ⅳ	1∶10	<0.15 mm	7±0.3
试验组Ⅴ	1∶10	0.5~2 mm	7±0.3

下载: 导出CSV

表 3 煤矸石连续动态淋滤试验条件

Table 3. Experimental conditions for continuous leaching of coal gangue

淋滤柱	粒径	pH	背景土
S1	0.15~1 mm	5±0.3	无
S2	0.15~1 mm	7±0.3	无
S3	0.15~1 mm	3±0.3	无
S4	<0.15 mm	5±0.3	无
S5	1~2 mm	5±0.3	无
S6	0.15~1 mm	5±0.3	有(5 cm)
S7	0.15~1 mm	5±0.3	有(10 cm)

下载: 导出CSV

表 4 煤矸石定量矿物分析结果

Table 4. Quantitative mineral analysis results of coal gangue

矿物成分	化学式	矿物相含量/%
矿物成分	化学式	天然煤矸石	淋滤后煤矸石
石英	SiO₂	30.4	29.0
方解石	CaCO₃	5.7	4.5
钠长石	NaAlSi₃O₈	6.0	6.0
白云母	K₂O·3Al₂O₃·6SiO₂·2H₂O	10.3	8.7
正长石	KAlSi₃O₈	5.7	6.1
高岭石	Al₂(OH)₄Si₂O₅	42.1	45.8
合计		100.0	100.0

下载: 导出CSV

表 5 不同浸泡条件下煤矸石中重金属元素浸出浓度

Table 5. Leaching concentration of heavy metal elements in coal gangue under different soaking conditions

试验组	重金属元素浸出浓度/(μg/L)
	As		Mn		Cu		Zn		Cd		Cr		Pb		Ni
	最大值	平均值	最大值	平均值	最大值	平均值	最大值	平均值	最大值	平均值	最大值	平均值	最大值	平均值	最大值	平均值
Ⅰ	15.796	9.424	12.222	4.022	3.358	1.761	2.257	0.470	0.108	0.046	1.576	1.207	0.079	0.040	1.811	1.423
Ⅱ	17.340	10.983^*	26.546	11.798^*	4.612	2.844^*	4.939	0.787^*	0.115	0.053^*	2.016	1.459^*	0.090	0.045	2.916	2.277^*
Ⅲ	14.112	8.295	9.597	4.081	1.066	0.761	0.690	0.274	0.103	0.039	1.209	0.916	0.065	0.034	1.196	0.956
Ⅳ	16.216	9.826	18.990	8.834	3.221	1.585	2.891	0.561	0.109	0.049	1.601	1.303	0.076	0.039	3.944	2.643
Ⅴ	8.864	6.030	9.762	4.223	1.905	1.439	1.043	0.318	0.108	0.045	1.146	0.931	0.085	0.045	1.336	0.960
注：*表示P<0.05.

下载: 导出CSV

表 6 煤矸石连续浸泡全过程的重金属元素最大释放率

Table 6. Maximum release rate of heavy metal elements in the whole process of continuous soaking of coal gangue

试验组	最大释放率/%
试验组	As	Mn	Cu	Zn	Cd	Cr	Pb	Ni
Ⅰ	0.94	0.04	0.13	0.02	0.42	0.04	<0.01	0.08
Ⅱ	0.52	0.05	0.09	0.02	0.23	0.02	<0.01	0.06
Ⅲ	1.69	0.07	0.09	0.01	0.81	0.05	0.01	0.11
Ⅳ	0.97	0.06	0.13	0.03	0.42	0.04	<0.01	0.17
Ⅴ	0.53	0.03	0.08	0.01	0.42	0.03	<0.01	0.06
注：最大释放率为水中溶解重金属元素的最大含量与煤矸石中重金属含量的比值.

下载: 导出CSV

表 7 不同淋滤pH下煤矸石重金属的累积释放量

Table 7. Cumulative release of heavy metals from coal gangue under different leaching pH values

淋滤柱	重金属累积释放量/(mg/kg)
淋滤柱	As	Mn	Cu	Zn	Cd	Cr	Pb	Ni
S1	0.045 0	0.103 2	0.044 1	0.056 9	0.001 9	0.012 1	0.000 3	0.014 6
S2	0.051 6	0.129 8	0.038 3	0.041 0	0.001 9	0.014 4	0.000 3	0.015 0
S3	0.042 8^*	0.194 1^*	0.049 1^*	0.104 8^*	0.001 9	0.010 1	0.000 3	0.017 7
注：*表示P<0.05.

下载: 导出CSV

参考文献(21)

[1]	杨越.我国煤矸石堆存现状及其大宗量综合利用途径[J].中国资源综合利用,2014,32(6):18-22. doi: 10.3969/j.issn.1008-9500.2014.06.009 YANG Y.Coal gangue stacked and its comprehensive utilization[J].China Resources Comprehensive Utilization,2014,32(6):18-22. doi: 10.3969/j.issn.1008-9500.2014.06.009
[2]	ZHOU C C,LIU G J,CHENG S W,et al.Thermochemical and trace element behavior of coal gangue,agricultural biomass and their blends during co-combustion[J].Bioresource Technology,2014,166:243-251. doi: 10.1016/j.biortech.2014.05.076
[3]	张彪,李岱青,高吉喜,等.我国煤炭资源开采与转运的生态环境问题及对策[J].环境科学研究,2004,17(6):35-38. doi: 10.3321/j.issn:1001-6929.2004.06.009 ZHANG B,LI D Q,GAO J X,et al.The eco-environment problems and countermeasures to be taken for coal development and transfer in China[J].Research of Environmental Sciences,2004,17(6):35-38. doi: 10.3321/j.issn:1001-6929.2004.06.009
[4]	丁帅帅,郑刘根,程桦.电感耦合等离子体发射光谱-逐级化学提取法研究低硫煤矸石中微量元素的赋存状态及其环境效应[J].岩矿测试,2015,34(6):629-635. DING S S,ZHENG L G,CHENG H.Study on the occurrence of trace elements in low-sulfur coal gangue and their environmental effect by inductively coupled plasma-optical emission spectrometry with sequential extraction procedure[J].Rock and Mineral Analysis,2015,34(6):629-635.
[5]	罗丽萍,刘应冬,范良千.攀枝花地区煤矸石中重金属元素浸出行为[J].矿产综合利用,2021(4):59-65. doi: 10.3969/j.issn.1000-6532.2021.04.009 LUO L P,LIU Y D,FAN L Q.Leaching behavior of main heavy metal from coal gangue in Panzhihua region[J].Multipurpose Utilization of Mineral Resources,2021(4):59-65. doi: 10.3969/j.issn.1000-6532.2021.04.009
[6]	HUA C Y,ZHOU G,ZHU X X,et al.Assessment of heavy metal in coal gangue:distribution,leaching characteristic and potential ecological risk[J].Environmental Science and Pollution Research,2018,25(32):32321-32331. doi: 10.1007/s11356-018-3118-4
[7]	LIU H M,WANG C B,GUO Y C,et al.Experimental and modeling study on the volatilization of arsenic during co-combustion of high arsenic lignite blends[J].Applied Thermal Engineering,2016,108:1336-1343. doi: 10.1016/j.applthermaleng.2016.07.187
[8]	金玲,郝成亮,吴立新,等.中国煤化工行业二氧化碳排放达峰路径研究[J].环境科学研究,2022,35(2):368-376. JIN L,HAO C L,WU L X,et al.Pathway of carbon emissions peak of China′s coal chemical industry[J].Research of Environmental Sciences,2022,35(2):368-376.
[9]	LIANG Y C,LIANG H D,ZHU S Q.Mercury emission from spontaneously ignited coal gangue hill in Wuda coalfield,Inner Mongolia,China[J].Fuel,2016,182:525-530. doi: 10.1016/j.fuel.2016.05.092
[10]	甄强,郑锋.煤的伴生资源煤矸石的综合利用[J].自然杂志,2015,37(2):121-128. ZHEN Q,ZHENG F.Comprehensive utilization of coal gangue as an associated resource with coal[J].Chinese Journal of Nature,2015,37(2):121-128.
[11]	王深,吕连宏,张保留.基于多目标模型的中国低成本碳达峰、碳中和路径[J].环境科学研究,2021,34(9):2044-2055. WANG S,LV L H,ZHANG B L.Multi objective programming model of low-cost path for China's peaking carbon dioxide emissions and carbon neutrality[J].Research of Environmental Sciences,2021,34(9):2044-2055.
[12]	周新华,舒悦,周亮亮,等.pH值对碱性煤矸石碱度和重金属释放规律影响研究[J].安全与环境学报,2022,22(5):2752-2758. ZHOU X H,SHU Y,ZHOU L L,et al.Study on effects of pH value on alkalinity and heavy metal release of alkaline coal gangue[J].Journal of Safety and Environment,2022,22(5):2752-2758.
[13]	段磊,孙亚乔,王晓冬,等.不同风化程度煤矸石中重金属释放及潜在生态风险[J].安全与环境学报,2021,21(2):874-881. doi: 10.13637/j.issn.1009-6094.2020.0306 DUAN L,SUN Y Q,WANG X D,et al.Potential ecological risks of heavy metals in the coal gangue and their release in different weathering degrees[J].Journal of Safety and Environment,2021,21(2):874-881. doi: 10.13637/j.issn.1009-6094.2020.0306
[14]	LI C,ZHENG L G,JIANG C L,et al.Characteristics of leaching of heavy metals from low-sulfur coal gangue under different conditions[J].International Journal of Coal Science & Technology,2021,8(4):780-789.
[15]	闫宝环,李凯荣,时亚坤.铜川市三里洞煤矸石堆积地风化土壤重金属污染及植物富集特征[J].水土保持通报,2012,32(3):47-50. YAN B H,LI K R,SHI Y K.Heavy metal contamination of weathered soil and enrichment characteristics of plants at sanlidong coal gangue site in Tongchuan City[J].Bulletin of Soil and Water Conservation,2012,32(3):47-50.
[16]	徐心远.煤矸石中重金属元素赋存形态及释出特征研究[D].焦作:河南理工大学,2015.
[17]	BU N J,LIU X M,SONG S L,et al.Synthesis of NaY zeolite from coal gangue and its characterization for lead removal from aqueous solution[J].Advanced Powder Technology,2020,31(7):2699-2710. doi: 10.1016/j.apt.2020.04.035
[18]	贾红霞,肖昕,张双,等.济宁三矿煤矸石中重金属释放规律的浸泡试验研究[J].洁净煤技术,2009,15(6):97-101. doi: 10.3969/j.issn.1006-6772.2009.06.029 JIA H X,XIAO X,ZHANG S,et al.Release rules of heavy metals in different Jining Ⅲ weathering gangue in immersion test[J].Clean Coal Technology,2009,15(6):97-101. doi: 10.3969/j.issn.1006-6772.2009.06.029
[19]	JIAN J S,WANG S,LUO F Z.Effects of coastal coal gangue highway on groundwater[J].Advanced Materials Research,2013,838-841:2518-2521. doi: 10.4028/www.scientific.net/AMR.838-841.2518
[20]	杨娅,季宏兵.新化矿区煤矸石中微量元素赋存形态及浸出特征[J].地球与环境,2016,44(1):36-46. doi: 10.14050/j.cnki.1672-9250.2016.01.005 YANG Y,JI H B.A study on chemical forms and leaching characteristics of trace elements in coal gangue from Xinhua coal mine in Guizhou Province,China[J].Earth and Environment,2016,44(1):36-46. doi: 10.14050/j.cnki.1672-9250.2016.01.005
[21]	张燕青,黄满红,戚芳方,等.煤矸石中金属和酸根离子的淋溶特性[J].环境化学,2014,33(3):452-458. doi: 10.7524/j.issn.0254-6108.2014.03.008 ZHANG Y Q,HUANG M H,QI F F,et al.The leaching characteristics of metals and acid radical ions in gangue[J].Environmental Chemistry,2014,33(3):452-458. doi: 10.7524/j.issn.0254-6108.2014.03.008