煤系锂和稀土的赋存特征与富集提取研究进展

张磊; 陈航超; 潘金禾; 何鑫; 马玉洁; 赵新迪; 周长春; 张宁宁

doi:10.13779/j.cnki.issn1001-0076.2023.06.001

煤系锂和稀土的赋存特征与富集提取研究进展

1.
中国矿业大学化工学院，江苏徐州 221116

2.
西安科技大学化学与化工学院，陕西西安 710054

基金项目: 国家自然科学基金青年项目（52204292）

详细信息

作者简介: 张磊（1998—），男，四川江油人，博士研究生，主要从事煤系战略性金属回收研究，E-mail：zhanglei-23@cumt.edu.cn

通讯作者: 潘金禾（1992—），男，山东烟台人，副教授，主要从事煤基固废和战略性金属分离纯化研究，E-mail：jinhepan@cumt.edu.cn。

中图分类号: TD849；TD98

收稿日期: 2023-11-13

刊出日期: 2023-12-25

Research Progress on Occurrence Characteristics, Enrichment and Extraction of Coal−based Lithium and Rare Earth

1.
School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China

2.
College of Chemistry and Chemical Engineering, Xi’an University of Science and Technology, Xi’an 710054, Shanxi, China

More Information

Corresponding author: PAN Jinhe, jinhepan@cumt.edu.cn

Received Date: 13 November 2023

Publish Date: 25 December 2023

摘要

摘要:
战略性关键金属锂和稀土是重要的工业原料，对社会发展和国家安全具有不可替代的作用，随着经济发展，锂和稀土的市场供需矛盾日益突出。煤系锂和稀土储量丰富，因此其提取回收受到了世界各国的广泛关注。通过综合分析当前国内外煤系锂和稀土的研究成果，总结了锂和稀土的赋存特征，系统阐述了分选富集和化学浸出方面的最新研究进展。针对现有分选方式富集倍数低、化学助剂消耗量大、废渣废水产量多等问题，建议开发物理−化学联用方式定向富集煤及其副产物中的锂和稀土元素，提升其品位，降低后续化学浸出难度。同时推进煤及其副产物中多种伴生资源协同提取、绿色开发研究，实现煤系资源高附加值综合利用。
- 锂 /
- 稀土 /
- 煤矸石 /
- 粉煤灰 /
- 赋存特征 /
- 物理分选 /
- 化学浸出
Abstract:
Lithium and rare earths as critical metals, are important industrial raw materials and play an irreplaceable role in promoting social and national security. With the development of economy, the contradiction of demand and support on lithium and rare earths has been intensifying. Coal−based lithium and rare earths reserves are abundant, of which the extraction and recovery has attracted widespread attention from countries around the world. Through a comprehensive analysis of the current research on coal−based lithium and rare earths at home and abroad, the progress on occurrence characteristics, beneficiation enrichment and chemical leaching of lithium and rare earths are systematically summarized, concluded and prospected. The challenges of their utilization contain unsatisfactory enrichment factors, high additives consumption, and high waste production of current technology. Thus, it is recommended to developed a physical−chemical combined method to directionally improve their grade, reducing the difficulty of subsequent chemical leaching. Furthermore, the research on the collaborative, green extraction other components in coal−based resources is promoted to achieve comprehensive utilization with high added value.
- lithium /
- rare earth /
- coal gangue /
- coal fly ash /
- occurrence characteristics /
- physical separation /
- chemical leaching

HTML全文

图 1 粉煤灰“分级—磁选”富集稀土元素流程^[68]

Figure 1.

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图 2 粉煤灰“一步酸溶法”工艺流程^[88]

Figure 2.

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图 3 煤矸石热活化—硝酸浸出—分离铁/镓—低温热解—水洗提纯工艺流程^[89]

Figure 3.

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表 1 不同粒度组分粉煤灰样中稀土元素的含量^[57]

Table 1. Contents of rare earth elements in coal fly ash samples of different particle size fractions^[57]

组分	SF^a1	SF2	SF3	SF4	SF5	原样
质量产率/%	7.30	13.50	20.30	35.30	23.60	100.00
MMD^b/μm	2.20	5.40	9.70	19.40	43.20	17.60
La/(μg·g⁻¹)	37.00	18.00	28.00	42.00	24.00	31.00
Ce/(μg·g⁻¹)	85.00	47.00	70.00	94.00	61.00	78.00
Pr/(μg·g⁻¹)	13.00	6.40	9.50	12.00	7.70	10.00
Nd/(μg·g⁻¹)	45.00	26.00	36.00	51.00	32.00	43.00
Sm/(μg·g⁻¹)	15.00	9.10	13.00	16.00	10.00	13.00
Eu/(μg·g⁻¹)	3.80	2.30	3.20	3.20	2.10	3.10
Gd/(μg·g⁻¹)	17.00	10.00	14.00	14.00	9.40	14.00
Tb/(μg·g⁻¹)	3.00	1.80	2.50	2.30	1.50	2.20
Dy/(μg·g⁻¹)	18.00	11.00	14.00	15.00	9.80	15.00
Ho/(μg·g⁻¹)	3.90	2.30	2.90	2.80	1.90	2.90
Er/(μg·g⁻¹)	12.00	6.70	8.50	8.00	5.30	8.30
Tm/(μg·g⁻¹)	1.70	1.00	1.20	1.10	0.74	1.10
Yb/(μg·g⁻¹)	13.00	7.10	8.60	7.80	4.80	7.90
Lu/(μg·g⁻¹)	2.10	1.20	1.40	1.30	0.71	1.30
REE/(μg·g⁻¹)	270.00	150.00	213.00	271.00	171.00	231.00
LREE/(μg·g⁻¹)	195.00	107.00	157.00	215.00	135.00	175.00
HREE/(μg·g⁻¹)	75.00	43.00	56.00	56.00	36.00	56.00
HREE/LREE/(μg·g⁻¹)	0.38	0.41	0.36	0.26	0.27	0.32
a：SF（size fractions）表示粒度组分，在第一个分级步骤中，从粉煤灰中分离出SF1（最细粒级），剩余粗粒粉煤灰作为第二步的入料，降低分级机转速，分离出SF2，再依次进行分级获得SF3、SF4和SF5； b：MMD（mass median diameters）表示质量中位直径。

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表 2 4种分选方法富集煤及其副产物中锂和稀土元素的特点

Table 2. Characteristics of enriching lithium and rare earth elements in coal and its by−products by four separation methods

方法	优势	不足
粒度分级	流程简单，适用范围广	富集倍数低
重选	适用范围广	流程较复杂，条件难控制
磁选	流程简单，效率高	仅适用于粉煤灰和部分原煤
浮选	效率高，富集倍数较高	流程较复杂，要求原料粒度细

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表 3 化学浸出法提取煤及其副产物中锂和稀土元素的特点

Table 3. Characteristics of extracting lithium and rare earth elements from coal and its by−products by chemical leaching

方法	优势	不足
直接浸出	流程简单	回收率低
空白焙烧—浸出	回收率高，流程经典可靠	仅适用于原煤和煤矸石，能耗高
助剂焙烧—浸出	回收率高，适用范围广	流程复杂，化学助剂消耗量大，废水废渣产量大

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