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Coal seam water infusion for dust control: a technical review

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Abstract and Figures

Coal mine dust continues to be a health and safety issue in underground coal mines. Coal seam water infusion was developed and widely applied in European coal mines for dust control, and was also a common practice in most Chinese coal mines. This method typically involves the infusion of water into the coal seam to increase its moisture content, and therefore reduce dust generation during mining operations. With the availability of other dust control methods such as water spraying systems, the water infusion method has not been considered as a viable means for dust mitigation in modern mines. However, the increase in production output and the deployment of more powerful equipment for coal cutting and transport and intensive gas drainage practices mean that workers could be exposed to more dust contaminations. Whilst the mine operators are committed to suppress and dilute airborne dust particles using these passive measures, there is a need to critically examine and subsequently develop this proactive dust control technology for practical applications in Chinese coal mines. The paper provides a critical review of the water infusion technologies in view of its technological advances and practical application limitations. The methods of water infusion, mechanism of water flow in coal, the role of surfactants and the key parameters influencing the effect of water infusion on dust control are identified and discussed. Existing problems and prospects for water infusion are analysed.
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REVIEW ARTICLE
Coal seam water infusion for dust control: a technical review
Kaixuan Zhang
1,2
&Jian Zhang
1,2
&Jianping Wei
2,3
&Ting Ren
4
&Xiangyu Xu
1,2
Received: 7 October 2018 /Accepted: 27 December 2018 /Pu blished online: 7 January 2019
#Springer-Verlag GmbH Germany, part of Springer Nature 2019
Abstract
Coal mine dust continues to be a health and safety issue in underground coal mines. Coal seam water infusion was developed and
widely applied in European coal mines for dust control, and was also a common practice in most Chinese coal mines. This
method typically involves the infusion of water into the coal seam to increase its moisture content, and therefore reduce dust
generation during mining operations. With the availability of other dust control methods such as water spraying systems, the
water infusion method has not been considered as a viable means for dust mitigation in modern mines. However, the increase in
production output and the deployment of more powerful equipment for coal cutting and transport and intensive gas drainage
practices mean that workers could be exposed to more dust contaminations. Whilst the mine operators are committed to suppress
and dilute airborne dust particles using these passive measures, there is a need to critically examine and subsequently develop this
proactive dust control technology for practical applications in Chinese coal mines. The paper provides a critical review of the
water infusion technologies in view of its technological advances and practical application limitations. The methods of water
infusion, mechanism of water flow in coal, the role of surfactants and the key parameters influencing the effect of water infusion
on dust control are identified and discussed. Existing problems and prospects for water infusion are analysed.
Keywords Water i nfu sio n .Dust control .Underground coal mine .Coal seam .Surfactant
Introduction
Underground coal mining is a risky industry. Risks are diverse
and include uncontrolled roof caving, rock bursts, gas out-
bursts and spontaneous combustion of residual coal in goafs.
Coal mine workers may also suffer from occupational diseases
under constant exposure of dusty airflow. The statistics reveals
that China currently has more than 810,000 pneumoconiosis
patients and more severely, 85~90% of them are simulta-
neously diagnosed with silicosis. Approximately 200,000
people die due to pneumoconiosis and 10,000~15,000 new
pneumoconiosis patients emerge annually in China (Zhu and
Lu 2017;Moetal.2014;Li2016; Zhang and Liu 2017). Not
only causing a health concern, coal dust may also become a
threat to coal mine safety when coal dust level falls into the
explosive range. According to the statistics, most coal mining
tragedies that caused more than 100 fatalities in one single
incident were triggered by a coal dust and gas explosion in
China (Zheng and Wang 2015). In Chinese coal mines, mines
with the danger of coal dust explosion comprise more than
60% of the total coal mines (Han et al. 2010). Thus it is
imperative to bring coal dust levels down to a safe level to
keep underground environment both safe and healthy to the
working crew.
According to the classification of coal mine dust source,
there are mainly two kinds (Jin et al. 2010): one is intrinsic
coal dust that is generated from geological process in a coal-
field, it mainly exists in coal and rock bedding, cleats and
fissures; the other is secondary coal dust that is generated from
the process of coal mining, handling and transport. To date
various techniques such as water mist, scrubber and water
infusion have been developed to mitigate dust generation
Kaixuan Zhang and Jian Zhang contributed equally to this work.
Responsible editor: Philippe Garrigues
*Jian Zhang
zhangjian@hpu.edu.cn
1
State Key Laboratory Cultivation Base for Gas Geology and Gas
Control, Henan Polytechnic University, Jiaozuo 454000, China
2
College of Safety Science and Engineering, Henan Polytechnic
University, Jiaozuo 454000, China
3
The Collaborative Innovation Center of Coal Safety Production of
Henan Province, Jiaozuo 454000, China
4
School of Civil, Mining & Environmental Engineering, University of
Wollongong, Wollongong, NSW 2522, Australia
Environmental Science and Pollution Research (2019) 26:45374554
https://doi.org/10.1007/s11356-018-04086-x
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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