A review of the health effects and exposure-responsible relationship of diesel particulate matter for underground mines

The increasing use of diesel-powered equipment in confined spaces(underground mines) has the potential to over expose underground miners under the threat of diesel particulate matter(DPM). Miners in underground mines can be exposed to DPM concentrations far more than works in other industries. A great number of animal and epidemiological studies have shown that both short-term and long-term DPM exposure have adverse health effect. Based on reviews of related studies, especially some recent evidence, this paper investigated the long and short-term health effects based on animal studies and epidemiological studies. The exposure-response relationship studies were also explored and compared to the current DPM regulation or standards in some countries. This paper found that the DPM health effect studies specifically for miners are not sufficient to draw solid conclusions, and a recommendation limit of DPM concentration can be put in place for better protection of miners from DPM health risk. Current animal studies lack the use of species that have similar lung functions as human for understanding the cancer mode of action in human. And finally, the DPM health hazard will continue to be a challenging topic before the mode of action and reliable exposure-response relationship are established.

Analysis of the Energy Efficiency of Diesel Oil Consumption in the Brazilian Iron Ore Mining Company

This paper aims to evaluate the diesel oil consumption between 2008 and 2015 in the production of iron ore in Brazil, creating correlations between energy intensity (production), economy and checking the impact of fuel prices on the commodity. During the analyzed period, the years 2008-2009 indicated economic crises, which interfered in the price and the commercialization of iron ore products. The physical intensity was 0.2% higher than the economic intensity. In the period from 2010 to 2014, economic activity remained more stable, with a decreasing trend, mainly due to the increase of iron ore prices. The physical intensity is much higher than the economic intensity influenced by the expansion of the Chinese economy. The year of 2014 indicated the end of the high iron ore price cycle and the beginning of supply and demand stabilization with consequent reduction in prices. In 2015, the market entered the stabilization phase, with a continuous reduction in unit production costs and transportation logistics. There was an abrupt change due to the strong increase of the economic intensity due to the fall of the international prices of iron ore. The diesel oil consumption plays a vital role in the scenario of cost reduction in iron ore production and a deeper analysis must be done in order to discover some options to change the energy matrix.

Diesel engine exhaust exposures in two underground mines

Exposure to diesel engine exhaust(DE) is a major concern in underground mines. It has been linked to cardiopulmonary diseases and is classified as a human carcinogen. The goal of this study is to assess DE exposures in workers at two underground gold mines, to compare exposure levels within and between the mines, and to compare different methods of measuring DE exposures, namely respirable combustible dust(RCD), elemental carbon(EC) and total carbon(TC). Ambient and personal breathing zone(PBZ) measurements were taken. Side-by-side monitoring of RCD and of the respirable fraction of EC and TC(EC_Rand TC_R) was carried out in the workers' breathing zone during full-shift work.Regarding ambient measurements, in addition to EC_R, TC_Rand RCD, a submicron aerosol fraction(less than 1 mm) of EC and TC was also sampled(EC_1and TC_1). Average ambient results of 240 mg/m^3 in RCD, 150 mg/m^3 in EC_Rand 210 mg/m^3 in TC_Rare obtained. Average PBZ results of 190 mg/m^3 in RCD,84 mg/m^3 in EC3Rand 150 mg/min TC_Rare obtained. Very good correlation is found between EC_Rand EC_1 with a Pearson correlation coefficient of 0.99(p < 0.01) calculated between the two logtransformed concentrations. No differences are reported between EC_Rand EC_1, nor between TC_Rand TC_1, since ratios are equal to 1.04, close to 1, in both cases. Highest exposures are reported for loadhaul-dump(LHD) and jumbo drill operators and conventional miners. Significant exposure differences are reported between mines for truck and LHD operators(p < 0.01). The average TC_R/EC_Rratio is 1.6 for PBZ results, and 1.3 for ambient results. The variability observed in the TC_R/EC_Rratio shows that interferences from non-diesel related organic carbon can skew the interpretation of results when relying only on TC data.

Diesel and welding aerosols in an underground mine

Researchers from the National Institute for Occupational Safety and Health(NIOSH)conducted a study in an isolated zone of an underground mine to characterize aerosols generated by:(1)a diesel-powered personnel carrier vehicle operated over a simulated light-duty cycle and(2)the simulated repair of existing equipment using manual metal arc welding(MMAW).Both the diesel-powered vehicle and MMAW process contributed to concentrations of nano and ultrafine aerosols in the mine air.The welding process also contributed to aerosols with electrical mobility and aerodynamic mobility count median diameters of approximately 140 and 480 nm,respectively.The welding particles collected on the filters contained carbon,iron,manganese,calcium,and aluminum.

Diesel generator exhaust heat recovery fully-coupled with intake air heating for off-grid mining operations:An experimental,numerical,and analytical evaluation

The customarily discarded exhaust from the fossil fuel-based power plants of the off-grid mines holds the thermal potential to fulfill the heating requirement of the underground operation.This present research fills in an important research gap by investigating the coupling effect between a diesel exhaust heat recovery and an intake air heating system employed in a remote mine.An integrative approach comprising analytical,numerical,and experimental assessment has been adapted.The novel analytical model developed here establishes the reliability of the proposed mine heating system by providing comparative analysis between a coupled and a decoupled system.The effect of working fluid variation has been examined by the numerical analysis and the possible improvement has been identified.Experimental investigations present a demonstration of the successful lab-scale implementation of the concept and validate the numerical and analytical models developed.Successful deployment of the fully coupled mine heating system proposed here will assist the mining industry on its journey towards energy-efficient,and sustainable mining practices through nearly 70%reduction in fossil fuel consumption for heating intentions.

井下硐室柴油蒸气泄漏扩散规律

随着柴油单轨吊和无轨胶轮车等辅助运输装置在煤矿井下的推广应用,在井下运输和加注柴油的频率越来越高,运输和加注柴油过程中泄漏的柴油和挥发的柴油蒸气会污染井下空气环境,严重时还可能造成燃烧与爆炸事故。针对煤矿井下柴油运输及加注过程的环境特点,构建了井下流态环境泄漏柴油蒸发扩散模型,建立了基于风速和蒸发速率的柴油蒸气体积分数峰值预测方法,研究了不同环境风速及柴油蒸发速率条件下的柴油蒸气体积分数分布规律,提出了煤矿井下柴油蒸气-瓦斯混合环境防火防爆措施。结果表明:在井下流态环境中,柴油蒸气扩散呈现出明显的沉降、分层及分段特性,风流对柴油蒸气扩散具有促进作用;当柴油泄漏后20s时,蒸气可扩散至距泄漏点下风侧10 m;当柴油泄漏后40 s时,蒸气可扩散至距泄漏点下风侧15 m;当柴油泄漏后70 s时,硐室中各监测点柴油蒸气体积分数达到峰值并趋于稳定;柴油蒸气体积分数峰值点位于泄漏点下风侧1 m处;可通过采用降低硐室环境温度、减少泄漏面积和增加风速等措施防止柴油蒸气-瓦斯混合气体燃烧和爆炸。

地下超细长输油主管结构稳定性分析

依托柴油机为动力的无轨车辆是金属非金属地下矿山开采的核心设备,如何安全、高效保障柴油运输始终是困扰矿山安全生产的关键问题。本文提出了几种形式的地下垂直输油管道系统及输油主管约束方式,并结合压杆稳定理论、ANSYS建模分析,开展了超细长输油主管的失稳分析、热应力分析及模态分析,对输油主管的结构稳定性进行了较为全面的考察,研究结果能够为地下垂直输油管道系统的设计提供理论参考依据。

矿区火电厂后备柴油发电机监控系统的设计与优化

矿区火电厂的生产环境复杂,一旦主电源出现故障,可能导致生产停滞、设备损坏甚至安全事故。因此,为保证稳定的电力供应,保护矿区生产和人员安全,有必要优化设计应用后备柴油发电机监控系统,在紧急情况下迅速启动,为关键设备提供电力,确保生产的连续性和安全性。鉴于此,本文分析了矿区柴油发电机的监控系统应用现状,明确柴油发电机组系统组成,而后就监控系统设计基本要求,以及监控系统设计结构及控制方法展开探讨,对该系统监控功能的具体实现进行分析,以期为更多矿区火电厂正常运行提供安全保障和支持。

ZJ-30钻机“油改电”技术在河南省煤矿区域水害治理工程中的应用

鉴于ZJ-30钻机在河南省煤矿区域水害治理中采用柴油作为动力源所带来的高能耗和重污染问题,研究开发了钻机“油改电”技术,采用网电替代柴油作为动力系统的钻机装置。改造实施后,每口井每天能够减少约1.2 t的柴油能源消耗,每月能够减少二氧化碳排放约150 t,减少二氧化硫排放约1.05 t,节能降耗和减排能力效果显著。

矿山自卸车起动控制过程及故障研究

早期的矿山自卸车一般使用机械泵柴油机,随着人们对发动机排放及油耗要求越来越高,矿山自卸车逐步开始使用大缸径系列电控柴油机。为了了解大缸径电控柴油机的起动过程,以及帮助维修人员更方便的解决电控柴油机起动过程中遇到的故障,本文对大缸径柴油机的起动过程原理进行了详细介绍,并对常见起动困难故障原因进行分类、总结。同时,本文通过故障处理的实例,介绍了大缸径电控柴油机起动故障的处理过程,为维修人员解决此类故障提供了参考。

矿用防爆柴油机智能故障诊断技术研究

针对矿用防爆柴油机故障排除耗时、依赖经验和检修工具落后等问题,设计了一种集防抖、故障处理、主从识别和信息存储于一体的故障诊断管理系统,显著提高了维护效率与可靠性。同时,结合售后维修需求,提出了一种搭载融合多种无线通信技术的智能诊断仪的远程故障诊断方案,实现了对防爆柴油机的远程故障诊断、实时监测和远程升级等功能,为煤矿行业的高效运营提供了有力支持。

CH_(4)浓度对于矿用防爆柴油机排放性能的影响研究

为了研究CH_(4)浓度对于矿用防爆柴油机排放性能的影响,进行了4次矿用防爆柴油机台架试验。通过低浓度配气装置来调节CH_(4)流量进而实现浓度调节,试验CH_(4)浓度分别为1.00%、0.50%、0.30%和0,空气的温度、湿度和压力由进气空调给定,在6个工况点进行试验并采集尾气进行分析。试验结果表明:CH_(4)浓度会对矿用防爆柴油机的排放性能产生影响,但由于矿井CH_(4)浓度一般不得高于0.50%,因此其对于矿用防爆柴油机的影响较小。

基于数据挖掘的钻完井柴油机气缸套使用寿命预测方法

目前的气缸套使用寿命预测方法难以全面覆盖运行中的复杂工况和多因素影响。基于此,文章基于数据挖掘技术,提出钻完井柴油机气缸套使用寿命预测方法。首先,整理收集到的钻完井柴油机气缸套使用寿命的影响特征数据,并进行数据集划分。其次,对数据集进行回归方程计算,探究多因素间的关系,评价并计算气缸套寿命极限。最后,对此方法进行测试。测试结果证明,该方法可以有效预测气缸套的使用寿命,有助于柴油机及时更换气缸套,确保机器正常运转。

EFT/B interference transmission model and method of anti-interference in a coal mine monitoring substation

Coal mining monitoring system has been enforcing tests for the immunity of Electromagnetic Compatibility(EMC) since 2006.However,not all monitoring substations can pass the Electrical Fast Transient/Burst(EFT/B) immunity test and the explosion-proof test simultaneously.In order to enhance EMC,the EFT/B interfere transmission model was presented at the substation power port,after the EFT/B test method was used to analyze the monitoring substation power ports.Hence,a low-pass filter was designed by using the simulation software PIPICE and an anti-jamming method was proposed by way of a parallel connection of the discharge interfere circuit and the low-pass filter.The improved complex EMI filter was made up of an interference discharge device and a filter.The dynamic equivalent circuit was proposed for the EFT/B immunity test.As a result,the monitoring substation has passed the EFT/B immunity and explosion-proof tests with the complex filter.It is concluded that the complex EMI filter has significantly enhanced the immunity of the coal mining monitoring system.

<i>In</i><i>Silico</i>Mining of EST-SSRs in Jatropha curcas L. towards Assessing Genetic Polymorphism and Marker Development for Selection of High Oil Yielding Clones

In recent years, Jatropha curcas L. has gained popularity as a potential biodiesel plant. The varying oil content, reported between accessions belonging to different agroclimatic zones, has necessitated the assessment of the existing genetic variability to generate reliable molecular markers for selection of high oil yielding variety. EST derived SSR markers are more useful than genomic markers as they represent the transcriptome, thus, directly linked to functional genes. The present report describes the in silico mining of the microsatellites (SSRs) using J. curcas ESTs from various tissues viz. embryo, root, leaf and seed available in the public domain of NCBI. A total of 13,513 ESTs were downloaded. From these ESTs, 7552 unigenes were obtained and 395 SSRs were generated from 377 SSR-ESTs. These EST-SSRs can be used as potential microsatellite markers for diversity analysis, MAS etc. Since the Jatropha genes carrying SSRs have been identified in this study, thus, EST-SSRs directly linked to genes will be useful for developing trait linked markers.

Parallel personal measurements of diesel engine exhaust and crystalline silica using dual sampling port

Diesel engine exhaust(DEE) and crystalline silica exposures occur simultaneously in the mining industry,and occupational sampling campaigns can be time-and cost-consuming. The authors evaluated a dualport system for simultaneous sampling of DEE and crystalline silica in laboratory and field conditions.Laboratory tests evaluated the operation of pumps during 8 h sampling and the intensity of the flow variation for various filter loading conditions and for different modes of operation. Field validation was performed in an underground mine. Pumps operated in constant flow or constant pressure modes.Tests in constant flow mode showed that when the flowrate increased on one side of the system, it decreased on the opposite side according to the loading intensity. Tests in constant pressure mode showed that flowrates systematically decreased when using loaded cassettes. However, the higher the backpressure setting, the lower the flow variation was. Flow variations during field tests were generally within the acceptable ±5% range. However, significant flow variations were identified in higher concentrations. A significant negative correlation was found between flowrate variation and total carbon concentration. While the majority of tests support the use of the dual-port for evaluating concomitant exposures, results highlight the possibility of filter overloading as a cause of flowrate changes.

防爆柴油机单轨吊分布式混合动力系统及模糊控制研究

针对传统防爆柴油机单轨吊存在的运行速度低、尾气污染严重等问题,为其设计了一种新型分布式混合动力驱动系统,制定了基于模糊规则的控制策略并进行了试验验证。首先,设计了分布式混合动力系统架构,制定了小坡度重载和大坡度轻载2种工况并完成主要部件选型及参数匹配;其次,基于模糊规则制定了控制策略并利用MATLAB建立控制模型;最后,利用AMESim和MATLAB开展联合仿真试验。结果表明,采用分布式混合动力系统并配合模糊控制策略,能够在大幅提升原单轨吊运行速度的同时,也显著降低其尾气污染程度。

基于气体介质的煤矿用防爆柴油机启动与安全保护系统研究

启动与安全保护系统是防爆柴油机的重要组成部分,启动困难与保护失效是防爆柴油机通常出现的故障问题。通过分析防爆柴油机的启动原理与安全保护要求,研究2种系统之间的关联性,设计出一套采用压缩空气为工作介质的启动与安全保护系统。研究系统中的主要元部件性能需求,分析计算系统中的运行参数,优化设计方案,通过系统设计解决防爆柴油机在启动与安全保护方面出现的问题。

220 t级矿用自卸车柴油发电机转动部件强度分析

本文探讨了电动轮驱动系统用柴油发电机转动部件的强度问题。有限元计算和联调试验结果显示,柴油发电机转动部件在工作转速范围内可安全稳定、平稳运行,证明了转动部件强度有限元计算结果的可靠性。

基于改进蜂群算法的井下防爆柴油车多目标优化

为了保障井下煤矿员工健康,响应碳中和号召,提出一种改进后的人工蜂群算法(modify artificial bee colony,Modify-ABC)来降低油耗、减少尾气排放。以5 t和8 t的井下防爆材料车为研究对象,建立防爆柴油机数学模型,提出降低有害气体排放及油耗的多目标优化模型,用Modify-ABC与其他3种算法进行对比,对目标函数进行优化求解。结果表明,Modify-ABC相比于传统蜂群算法,遗传算法和模拟退火算法收敛速度更快更好,使用改进算法后,井下5 t材料车油耗及有害气体排放量减少了25%,8 t材料车油耗及有害气体排放量减少了24.8%。