选煤厂粉尘治理实践

粉尘问题是影响选煤厂高效安全洁净生产的重要问题,本文结合生产和选煤厂设计的实际,分析了粉尘产生和扩散的原因,对选煤厂的粉尘治理进行了综合性探讨。并以破碎筛分车间粉尘治理的实践介绍了选煤厂粉尘治理的情况。论文最后对粉尘治理的实践进行进一步深入的理论探讨。     

粉尘爆炸防护措施的研究进展

随着工业现代化的发展,粉末技术应用越来越广泛。由于人们对不同物料粉尘的危害认识不清,特别是粮食粉尘和金属粉尘爆炸机理和防治技术研究不够系统、深入,缺乏有效的粉尘爆炸安全防护,导致最近几年粉尘爆炸事故频繁发生。为预防和控制粉尘爆炸事故,更加深入地了解粉尘爆炸,首先从粉尘爆炸的机理和必要条件介绍了粉尘爆炸;其次,总结了粉尘爆炸防护措施的试验研究现状,对惰化技术、泄爆技术、抑爆技术3个方面进行阐述。此外,分析目前防护措施的不足,并提出将来发展的方向,为粉尘爆炸防护研究提供引导作用。     

露天矿爆破粉尘排放量影响因素分析及试验研究

露天矿爆破作业是粉尘排放的最大来源,粉尘排放不仅对环境造成污染,而且对人员身体健康造成威胁。为了定量分析爆破粉尘排放量,制定更加有效的防尘措施,以缅甸某露天矿山爆破作业为背景,对影响爆破粉尘浓度和排放量的因素进行了现场试验研究。通过合理设置实验方案,测得多点粉尘浓度及粉尘沉降量,结合粉尘污染扩散理论,采用函数拟合的方法,对不同药量和水封高度条件下的爆破粉尘排放量进行对比分析,得到了炸药量和水封高度与粉尘排放量的数量关系。结果表明:炸药用量增加10%,粉尘排放量增加达25%;采用水封爆破手段时粉尘吸收量最高达63%,验证了水封爆破降尘的有效性。     

采掘工作面的尘源与煤矿粉尘防治技术

讨论了采掘工作面粉尘的构成和各因素对工作面粉尘生成的影响，介绍了各种粉尘防治技术及其效果，并提出了形成工作面粉尘的主要根源一一一截割粉尘及其影响因素，为开创粉尘防治的新思路、从根本上降低工作面的粉尘奠定了思想基础。     

采掘工作面的尘源与煤矿粉尘防治技术

讨论了采掘工作面粉尘的构成和各因素对工作面粉尘生成的影响，介绍了各种粉尘防治技术及其效果，并提出了形成工作面粉尘的主要根源——截割粉尘及其影响因素，为开创粉尘防治的新思路、从根本上降低工作面的粉尘奠定了思想基础。     

拆除爆破粉尘控制研究现状与前景

综述了爆破粉尘控制的研究现状,分析了爆破粉尘的特点,对拆除爆破粉尘的控制方法进行了探讨,预测了拆除爆破粉尘控制的发展趋势。文中提出了采用清除积尘、预湿建筑物、爆炸水雾、局部建筑单元蓄水、喷淋等综合除尘方法降低城市控制爆破过程中的粉尘,以减轻和消除爆破粉尘对环境的污染。     

浅谈采掘工作面的尘源与煤矿粉尘防治技术

本文主要以采掘工作面粉尘的构成和各因素对工作面粉尘生成的影响为主题，详细阐述了各种粉尘防治技术及其效果，并提出了形成工作面粉尘的主要根源——截割粉尘及其影响因素，为开创粉尘防治的新思路、从根本上降低工作面的粉尘奠定了思想基础。     

纸盒包装生产线粉尘运移规律研究

目的 研究全自动高速纸盒包装生产线上气流和粉尘的运移规律,从而提供合理的控尘方案.方法 利用Ansys Fluent软件对某制药厂纸盒生产线上气流与粉尘的运动进行仿真模拟,并与现场实测数据进行比较.结果 气流与粉尘的运移轨迹基本一致;在开盒工位,含尘气流互相掺杂,粉尘扩散范围广,落尘严重;在说明书堆叠工位,粉尘受阻碍回流大量散落在承载台表面;在合盒工位,粉尘易团聚落入机构内部;在纸盒料仓工位,部分粉尘因静电吸附在传送带上,未降落粉尘随气流进入开盒区域.结论 文中控尘方案在说明书和纸盒料仓工位设置了吸尘口,以减少粉尘的输出,在开盒工位处设置了吸尘口以阻断粉尘的运移,达到了有效的除尘和控尘效果.     

锦界选煤厂粉尘治理实践

粉尘问题是影响选煤厂高效安全洁净生产的重要问题,本文结合本选煤厂的生产和实际,分析了粉尘来源所产生和扩散的原因,对选煤厂的粉尘治理进行了综合性探讨。综合破碎车间对本选煤厂粉尘治理的情况做以实践分析。     

基于图像处理测量露天爆破粉尘量

以缅甸莱比塘铜矿为研究对象,开展露天爆破粉尘测量方法的研究。采用数码相机对爆破粉尘进行摄影,获取了不同浓度粉尘图像灰度值数据,通过对粉尘浓度实际测量,建立了粉尘浓度值与图像灰度值的数学关系,分析粉尘图像灰度特征获得了粉尘浓度空间分布规律,计算得到起爆后某一时刻爆区空气爆破粉尘总量。研究结果表明:爆区正侧方50m处起爆后96s内平均粉尘浓度为1 602mg/m~3;粉尘浓度与粉尘图像灰度的比例系数k为9.117mg/m~3;起爆后30s时形成粉尘体的浓度由内向外逐渐降低,边缘浓度急剧降低,宽度方向浓度近似相等;起爆后30s时空气中爆破粉尘总量为864.91kg。     

Estimation of Parameters of Universal Distribution of Moments of Failure of Products

A method is proposed for estimating the parameters of a mixture of exponential and Weibull distributions for which the accuracy of preliminary estimates obtained by graphical analysis is refined in accordance with the criterion of maximum likelihood. The efficiency of the proposed method is supported by the results of statistical modeling.     

Evaluation of optical properties of highly scattering media by moments of distributions of times of flight of photons

A novel method for the determination of the optical properties of tissue from time-domain measurements is presented. The data analysis is based on the evaluation of the first moment and the second centralized moment, i.e., the mean time of flight and the variance of the measured distribution of times of flight (DTOF) of photons injected by short (picosecond) laser pulses. Analytical expressions are derived for calculation of absorption and of reduced scattering coefficients from these moments by application of diffusion theory for infinite and semi-infinite homogeneous media. The proposed method was tested on experimental data obtained with phantoms, and results for absorption and reduced scattering coefficients obtained by the proposed method are compared with those obtained by fitting of the same data with analytical solutions of the diffusion equation. Furthermore, the accuracy of the moment analysis was investigated for a range of integration limits of the DTOF. The moment analysis may serve as a comparatively fast method for evaluating optical properties with sufficient accuracy and can be used, e.g., for on-line monitoring of optical properties of biological tissue.     

Analysis of the rate of propagation of the wave of change of boiling modes

An approximate analytical expression is derived for the velocity of the front of the wave of change of boiling modes on a rod and on a plate. The impact of the Thomson effect and of the heater orientation in the gravity field is included. Adequate agreement is demonstrated between the derived relations and experimental data.     

Estimation of potentialities of methods of summation of direct measurement errors

Conventional methods for summation of direct measurement errors are considered. Conditions under which these methods provide consistent results are stated. It is proposed to utilize for characteristic of the total error, its interval estimator or the half-sum of the value obtained by adding up its arithmetic and geometric random errors.Translated from Izmeritel'naya Tekhnika, No. 4, pp. 10–12, April, 1995.     

空压机轴承箱蜗壳温度探头油封改造

由于空压机进气侧轴承箱蜗壳温度探头密封效果不好,使空压机及其后续管道受到油污染。后将温度探头的O形圈密封改为骨架油封,杜绝了轴承箱漏油问题。文章简介空压机的结构和技术参数,详细介绍了骨架油封的制作和优点。     

Characteristics of mechanical properties of materials in studies of conditions of attainment of marginal states

It is shown that conditions of attainment of marginal states in the material of structural components are formulated on the basis of analysis of force and deformation criteria of formation and development of destruction. The parameters of these criteria are data on types of structural materials, standard and special characteristics of their mechanical properties, structural forms of considered elements of the equipment, and their operating stress loading. In this case, the construction of a system of state equations for describing interrelation of current damage, external actions, and responses to them is based on the concept of calculating variations in properties of materials at all stages of the design life cycle.     

Determination of parameters of microstructural inhomogeneity of deformation of metals by the method of modeling

The article suggests a method of evaluating the microstructural inhomogeneity of deformation of metals by modeling. The method includes the measurement of deformations of metal according to meshes of a dividing grid with small base and the calculation of the distribution parameters of microdeformations in model representation. It is shown that the modeling method makes it possible objectively to evaluate the microinhomogeneity of deformation of metals independently of the chosen mesh size of the dividing grid. New structural characteristics are introduced: the base and wave of variation expressing the degree of crumbling or amalgamation of metal grains by inhomogeneity of deformation.Translated from Problemy Prochnosti, No. 7, pp. 40–44, July, 1991.     

水三相点复现的不确定度评定

水三相点是开尔文热力学温度的唯一基准点，也是ITS-90国际温标重要的定义固定点。因此，水三相点不确定度分析对整个温标的建立、温度量值传递起着至关重要的作用。近3年来，中国计量科学研究院研制出一系列高质量的水三相点容器，加强了水三相点的研究，为不确定度的分析提供了更为可靠的实验依据。同时，不确定度的分析也是客观评价新研制容器性能的一个重要指标。因此，根据实验结果对新研制容器所复现的水三相点进行了不确定度评定。评定结果表明，其扩展不确定度为0．16mK(k=2．69，P=0．99)。