Chemical compositions and technological properties of low-rank coals in the south Shenfu mining area: Characteristics, relationship and practice

Authors

GUO Chen, College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an 710054, China; Geological Research Institute for Coal Green Mining, Xi'an University of Science and Technology, Xi'an 710054, China; Center for Post-doctoral Studies of Geological Resources and Geological Engineering, Xi'an University of Science and Technology, Xi'an 710054, China
WANG Shengquan, College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an 710054, China; Geological Research Institute for Coal Green Mining, Xi'an University of Science and Technology, Xi'an 710054, ChinaFollow
SHI Qingmin, College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an 710054, China; Geological Research Institute for Coal Green Mining, Xi'an University of Science and Technology, Xi'an 710054, China; Center for Post-doctoral Studies of Geological Resources and Geological Engineering, Xi'an University of Science and Technology, Xi'an 710054, China
QIAO Junwei, College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an 710054, China; Geological Research Institute for Coal Green Mining, Xi'an University of Science and Technology, Xi'an 710054, China; Center for Post-doctoral Studies of Geological Resources and Geological Engineering, Xi'an University of Science and Technology, Xi'an 710054, China
LI Huantong, College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an 710054, China
ZHANG Weiguo, College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an 710054, China
LI Jun, Shenmu Zhangjiamao Mining Co. Ltd., Shaanxi Coal Group, Yulin 719316, China
ZHANG Chi, Shenmu Zhangjiamao Mining Co. Ltd., Shaanxi Coal Group, Yulin 719316, China
WANG Xiaokang, College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an 710054, China; Geological Research Institute for Coal Green Mining, Xi'an University of Science and Technology, Xi'an 710054, China
DU Fangpeng, College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, China; Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation, Xi'an 710054, China; Geological Research Institute for Coal Green Mining, Xi'an University of Science and Technology, Xi'an 710054, China; Center for Post-doctoral Studies of Geological Resources and Geological Engineering, Xi'an University of Science and Technology, Xi'an 710054, China

Abstract

Coal grading utilization is an essential way to fit its high-efficiency, clean and green development trends. Understanding the basic chemical composition and key technological properties of coal is the basis for achieving grading and qualitative utilization of coal resources. The South Shenfu mining area in Shaanxi Province is rich in coal reserves and it is an important low-rank coal production base in West China. However, it has not been able to achieve the qualitative utilization of coal practically completely for a long time, which restricts the full play of the value of coal resources and the further improvement of coal economic and social benefits. Based on this background, the low-rank coal samples were collected from the South Shenfu mining area to carry out coal chemical composition and technological property tests. The chemical composition tests include industrial components, major elements, total sulfur and form sulfur, harmful element P and coal ash composition. Technological property tests include calorific value, low-temperature carbonization, thermal stability and coal ash melting temperature. Quantitative analysis method was used to reveal the chemical compositions and technological properties of coal and their internal relationships. A mathematical model for predicting technological properties based on chemical compositions is constructed to provide a foundation for the grading and qualitative utilization of coal. The results show that:1) The low-rank coal resources in the study area are characterized by ultra-low ash, ultra-low sulfur, ultra-low phosphorus, high-very high calorific value, oil-rich, high thermal stability, and weak-non-adhesion characteristics, presenting a significant advantages in grading and qualitative utilization, especially the widely distributed oil-rich coal should be highly valued; 2) There is a close genetic relationship between the technological properties and chemical compositions of coal. The calorific value is positively correlated with the fixed carbon content, and the low-temperature carbonization tar yield is positively correlated with the volatile yield and hydrogen content. The moisture content determines the total moisture yield of low-temperature carbonization, and under specific coal type conditions, ash yield is a key factor controlling many technological properties of coal, including calorific value, cohesiveness, tar yield, etc., all presenting negative correlations; 3) Based on stepwise regression analysis and saliency test, a series of mathematical models for predicting the key technological properties of coal based on chemical compositions were built. Taking Zhangjiamao Mine as an example, the model was used to predict the tar yield of low-temperature carbonization and the distribution of oil-rich coal. The prediction results were consistent with the actual situation, verifying the reliability of the model. The mathematical models permit the further investigation on the coal technological properties and oil-rich coal distribution based on the geological data obtained during the previous coal exploration period. The research results have enriched the basic understanding of the material compositions and chemical properties of low-rank coals in terretrial basin, and described their intrinsic relationship and quantitative models, which can provide a theoretical foundation for the scientific evaluation and optimal utilization of high-quality coal resources(oil-rich coal) in the south Shenfu mining area and other similar areas.

Keywords

oil-rich coal, technological property, tar yield, prediction model, grading utilization

DOI

10.3969/j.issn.1001-1986.2021.01.009

Recommended Citation

GUO Chen, WANG Shengquan, SHI Qingmin, et al. (2021) "Chemical compositions and technological properties of low-rank coals in the south Shenfu mining area: Characteristics, relationship and practice," Coal Geology & Exploration: Vol. 49: Iss. 1, Article 10.
DOI: 10.3969/j.issn.1001-1986.2021.01.009
Available at: https://cge.researchcommons.org/journal/vol49/iss1/10

Reference

[1] 尚建选,王立杰,甘建平,等. 煤炭资源逐级分质综合利用的转化路线思考[J]. 中国煤炭,2010,36(9):98-101. SHANG Jianxuan,WANG Lijie,GAN Jianping,et al. Thinking of conversion route of comprehensive utilization of coal resources by categories and qualities[J]. China Coal,2010,36(9):98-101.

[2] 尚建选,王立杰,甘建平. 陕北低变质煤分质综合利用前景展望[J]. 煤炭转化,2011,34(1):92-96. SHANG Jianxuan,WANG Lijie,GAN Jianping. Prospect of the Shanbei comprehensive coal grading utilization technology[J]. Coal Conversion,2011,34(1):92-96.

[3] 潘生杰,陈建玉,范飞,等. 低阶煤分质利用转化路线的现状分析及展望[J]. 洁净煤技术,2017,23(5):7-12. PAN Shengjie,CHEN Jianyu,FAN Fei,et al. Present situation analysis and prospect of low rank coal quality-based utilization conversion route[J]. Clean Coal Technology,2017,23(5):7-12.

[4] 胡广青,王文峰. 煤炭资源分质清洁利用研究进展与总体设想[J]. 淮南职业技术学院学报,2019,19(5):1-2. HU Guangqing,WANG Wenfeng. Research progress and overall assumption of coal resources classification and clean utilization[J]. Journal of Huainan Vocational and Technical College,2019,19(5):1-2.

[5] 曲洋. 煤炭供应全过程清洁化发展方向研究[J]. 煤炭经济研究,2019,39(4):66-70. QU Yang,Research on the high-quality development direction of the whole process of coal cleaning supply[J]. Coal Economic Research,2019,39(4):66-70.

[6] 梁嘉琨. 坚持科技创新,促进煤焦化产业转型升级,推进煤炭由燃料向原料与燃料并举转变[J]. 中国煤炭工业,2013(8):7-9. LIANG Jiakun. Insist on technological innovation,promote the transformation and upgrading of the coal coking industry,and promote the transformation of coal from fuel to raw materials and fuel[J]. China Coal Industry,2013(8):7-9.

[7] 张群,窦廷焕. 陕西省主要矿区煤质特征及工业利用评价[J]. 陕西煤炭技术,1991,3:52-60. ZHANG Qun,DOU Tinghuan. Coal quality characteristics and industrial utilization evaluation in Shaanxi Province[J]. Shaanxi Coal Technology,1991,3:52-60.

[8] 宋成建,曲建林,王昊,等. 低温热处理对神府煤成浆性影响的机理研究[J]. 西安科技大学学报,2015,35(6):738-744. SONG Chengjian,QU Jianlin,WANG Hao,et al. Influenctial mechanism of low temperature thermal treatment on the slurrying ability of Shenfu coal[J]. Journal of Xi^'an University of Science and Technology,2015,35(6):738-744.

[9] 何建国,秦云虎,王双美,等. 神府矿区5^-2煤层煤质特征及其气/液化性能评价[J]. 煤炭科学技术,2018,46(10):228-234. HE Jianguo,QIN Yunhu,WANG Shuangmei,et al. Evaluation on gasification and liquefaction performance for No.5^-2 coal seam and its coal quality characteristics in Shenfu Mining Area[J]. Coal Science and Technology,2018,46(10):228-234.

[10] 魏云迅,李聪聪,乔军伟,等. 神府矿区洁净煤划分及绿色开发建议[J]. 中国煤炭,2019,45(11):79-83. WEI Yunxun,LI Congcong,QIAO Junwei,et al. Clean coal grading and green development proposal of Shenfu Mining Area[J]. China Coal,2019,45(11):79-83.

[11] 王双明. 鄂尔多斯盆地聚煤规律及煤炭资源评价[M]. 北京:煤炭工业出版,1996:377-382. WANG Shuangming. Coal accumulation law and coal resource evaluation in Ordos Basin[M]. Beijing:Coal Industry Press,1996:377-382.

[12] 刘晓东. 陕北侏罗纪煤田煤炭资源勘查利用现状分析[J]. 地下水,2017,39(5):126-128. LIU Xiaodong. Analysis on the status of coal resources exploration and utilization in Jurassic Coalfields in northern Shaanxi[J]. Groundwater,2017,39(5):126-128.

[13] 王双明. 对我国煤炭主体能源地位与绿色开采的思考[J]. 中国煤炭,2020,46(2):11-16. WANG Shuangming. Thoughts about the main status of coal and green mining in China[J]. China Coal,2020,46(2):11-16.

[14] 段中会,贺丹,贺晓浪,等. 陕西煤炭产业转型与生态环境保护的若干思路[J]. 陕西煤炭,2016,35(4):5-8. DUAN Zhonghui,HE Dan,HE Xiaolang,et al. The thoughts on transformation development of coal industry and ecological environment protection[J]. Shaanxi Coal Society,2016,35(4):5-8.

[15] 王双明,段中会,马丽,等. 西部煤炭绿色开发地质保障技术研究现状与发展趋势[J]. 煤炭科学技术,2019,47(2):1-6. WANG Shuangming,DUAN Zhonghui,MA Li,et al. Research status and future trends of geological assurance technology for coal green development in western China[J]. Coal Science and Technology,2019,47(2):1-6.

[16] 王双明,孙强,乔军伟,等. 论煤炭绿色开采的地质保障[J]. 煤炭学报,2020,45(1):8-15. WANG Shuangming,SUN Qiang,QIAO Junwei,et al. Geological guarantee of coal green mining[J]. Journal of China Coal Society,2020,45(1):8-15.

[17] 秦勇,王作棠,韩磊. 煤炭地下气化中的地质问题[J]. 煤炭学报,2019,44(8):2516-2530. QIN Yong,WANG Zuotang,HAN Lei. Geological problems in underground coal gasification[J]. Journal of China Coal Society,2019,44(8):2516-2530.

[18] 袁亮. 我国煤炭工业高质量发展面临的挑战与对策[J]. 中国煤炭,2020,46(1):6-12. YUAN Liang. Challenges and countermeasures for high quality development of China's coal industry[J]. China Coal Society,2020,46(1):6-12.

[19] 郭晨,秦勇,韩冬. 黔西比德-三塘盆地煤层气井产出水离子动态及其对产能的指示[J]. 煤炭学报,2017,42(3):680-686. GUO Chen,QIN Yong,HAN Dong. Ions dynamics of produced water and indication for CBM production from wells in Bide-Santang Basin,Western Guizhou[J]. Journal of China Coal Society,2017,42(3):680-686.

[20] 马丽,拓宝生. 陕西富油煤资源量居全国之首,榆林可"再造一个大庆油田"[J]. 陕西煤炭,2020,39(1):220-222. MA Li,TUO Baosheng. The oil-rich coal resources in Shaanxi Province rank first in China,and Yulin can "rebuild a Daqing Oilfield"[J]. Shaanxi Coal Society,2020,39(1):220-222.

[21] 茆艳丽,陈建国. 浅谈低阶煤试验过程中的影响因素及控制措施[J]. 中国石油和化工标准与质量,2017,37(23):99-100. MAO Yanli,CHEN Jianguo. Influencing factors and control measures during the test of low rank coal[J]. China Petroleum and Chemical Standards and Quality,2017,37(23):99-100.