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171.
焦作矿区煤矸石山周围土壤和玉米作物重金属污染研究 总被引:3,自引:0,他引:3
以焦作演马矿区为例,研究煤矸石长期堆放对周围土壤和玉米作物造成的重金属污染。根据当地地形地貌在矸石堆周围呈放射状布设3条采样线,用HCl-HNO3-HF—HClO4全分解法和HNO3-HClO4湿法消解土壤和玉米样品,检测土壤和玉米(叶、茎和籽)中主要有害重金属元素(Pb、Cu、Cr、Zn)。研究表明:土壤和玉米中Pb和Zn含量超标,且距离矸石堆由近及远土壤和玉米作物中重金属含量呈下降趋势,重金属在玉米作物不同部位的富集能力表现为叶中最高,茎次之,籽最低。 相似文献
172.
Accurate detection of CO gas is crucial to the prevention of coal combustion. Tuneable diode laser absorption spectroscopy (TDLAS) is a reliable method for CO detection during coal combustion. The influences of temperature and pressure cause changes in the line strength and linewidth of the index gases’ absorption spectra, leading to sizable measurement errors. To correct the distortion of the CO absorption spectrum caused by temperature and pressure fluctuation, a compensation model based on the grey wolf optimizer–support vector machine (GWO–SVM) was proposed. The results were compared with those of the single SVM, the back propagation neural network (BPNN), and multiple regression analysis (MRA). MRA was revealed to result in the lowest accuracy, which indicated that MRA is not ideal for compensation in TDLAS. The hyperparameter selection of the SVM had the disadvantages of randomness and blindness, which led to instability and large errors. The BPNN achieved better correction in the training stage, but severe overfitting occurred in the testing stage. The modified results revealed that the GWO–SVM model had higher accuracy and stability than the other models. It effectively inhibited the effects of temperature and pressure on the measured concentration and greatly improved the measurement accuracy. The equipment is thus suitable for CO gas detection with the aim to preventing coal combustion loss, and it can be further applied to loss prevention in other process fields. 相似文献
173.
174.
介绍华能国际电力股份有限公司丹东电厂现采用的一炉一塔石灰石一石膏湿法脱硫方案.主体工程包括烟气系统和二氧化硫吸收系统,配套脱硫剂制备系统、石膏脱水系统等,设计脱硫效率95%,脱硫保证率为90%以上. 相似文献
175.
176.
我国煤炭资源赋存丰富且条件复杂,历年开采引发或加剧众多矿山地质环境问题。本文以煤炭资源开发各环节活动及开采形式为基础.分析和探讨了煤矿建设和生产对矿山地质环境的影响,探讨了问题类型及特征,并给出了不同开采形式对矿山地质环境影响的关系,并提出了矿山地质环境问题防治工作进一步开展的几点建议,对我国发展绿色、高效矿山有一定促进作用。 相似文献
177.
针对造纸废水中含有木质素聚糖类、纤维素和碱浓度较高等特点,利用灰水混合体良好的吸附与沉降特性,通过热电厂粉煤处置系统对木浆造纸废水进行处理。结果表明,利用该工艺处理造纸废水可降低污染负荷65%以上,为降低造纸污水污染负荷提供了一个以废治废的有效途径。 相似文献
178.
高浓度洗煤废水治理方法的研究 总被引:2,自引:0,他引:2
分析了高浓度洗煤废水的性质及其难于处理的原因,提出了采用CaCl2+PAM混凝沉淀法处理该种废水的方法,并通过实验确定了主要技术参数.实验结果表明,该方法处理效果显著,不仅有较高的清水分离率,而且出水的各项指标均达到国家排放标准. 相似文献
179.
This paper addresses the distribution and occurrence of harmful organic substances in coal gangue dump from Jiulong Coal Mine
and its influence on the environment. The samples were taken from the coal gangue dump and coal waste water stream and analyzed
by organic geochemical methods. The results indicate that the coal gangues contain abundant harmful organic substances like
polycyclic aromatic hydrocarbons. The TOC and sulfur contents of the samples are much higher than those of the background
sample except Sample JL7. The contents of organic bulk parameters are relatively high. Ten carcinogenic PAHs were identified
and these harmful organic substances have influenced the surrounding area. Along the waste water stream, organic substances
pollute at least 1,800 m far from the coal gangue dump. 相似文献
180.
Self-ignition in coal stockpiles is a serious economic, environmental and safety problem. Evaluation is an effective way to identify the self-ignition hazards in implicit environment of coal piles and provides a guide for countermeasures against spontaneous combustion in coal piles. In this paper, a comprehensive evaluation system is proposed. The trapezoidal and the triangular extent fuzzy AHP methods are employed to handle the imprecision and uncertainty of the effects of factors. A coal stockpile stored at the Bulk Cargo Logistics of Tianjin Port of China and three coal piles in the Teruel basins of Spain are studied to demonstrate the validity of the index system and the effectiveness of fuzzy AHP approaches. The evaluated results indicate that the proposed evaluation system and approaches are valid and objective for evaluating self-ignition risks of coal stockpiles; compared with the trapezoidal fuzzy AHP method, the triangular extent fuzzy AHP approach is more effective to evaluate self-ignition risks of coal piles for the priorities of factors impacting self-ignition risks are highlighted by their weight comparisons' calculation using the triangular extent analysis. The comprehensive evaluation system is beneficial to manage self-ignition risks of coal piles from a holistic point of view and to establish an early warming system of self-ignition risks of coal piles. 相似文献