基于透射散射光的宽分布煤矿粉尘在线检测原理及方法研究

Mine dust is the main source of dust explosion and miners’ pneumoconiosis, so it is important to monitor the mine dust in real time. A new method of dust measurement was proposed based on transmitted light and scattered light. Combining total scattering with angle scattering principles and taking advantage of the characteristics that total scattering is sensitive to small particles and angle scattering is sensitive to large particles, the model of light transmission-scattering will be built and the wide particle size distribution of dust will be inversed with high-precision. Based on Mie scattering theory, photon transmission in particle group will be simulated and analyzed statistically. Then, the mathematical model of the relation between scattering and transmission intensity, light wavelength, particle size distribution and concentration of dust will be established. According to the model, non-mode particle size inversion algorithm which combines total scattering with angle scattering will be built. Particle size distribution and concentration of dust with wide range will be calculated fast and accurately. On the basis of theoretical research, experimental platform will be set up. Test facility will be calibrated using standard particles. Particle groups of different particle size distribution will be studied and compared with the detection result of scanning electron microscopy, thus verifying the validity and reliability of the system. The findings of this project can be used to develop dust concentration monitor which can monitor the mine dust in real time..

煤矿粉尘是煤矿粉尘爆炸事故及矿工尘肺的主要来源，因此在煤矿中对煤矿粉尘进行实时监测具有重要的意义。本项目提出透射散射光粉尘测量方法，结合全散射和角散射原理，利用全散射光对小颗粒敏感、角散射对大颗粒敏感的特点，建立光透射散射模型，实现煤矿宽分布粉尘颗粒粒径的高精度反演。在米氏散射理论基础上，模拟光子在颗粒群中的传输过程，并做统计分析，建立散射和透射光强与光波波长、粉尘颗粒粒径分布、浓度之间的光透射散射数学模型，根据数学模型建立非约束模式的全散射和角散射相融合的透射散射光颗粒粒径反演算法，实现宽分布煤矿粉尘的粒径分布及浓度的快速、准确计算。在理论研究的基础上，搭建实验平台，利用标准颗粒对测试装置进行标定，并对不同粒径分布的颗粒群进行实验研究，与扫描电镜的检测结果作对比，对系统的正确性和可靠性进行验证。该项目的研究成果可开发成矿用粉尘浓度监测仪，对煤矿粉尘进行实时监控。

煤矿粉尘是煤矿粉尘爆炸事故及矿工尘肺的主要来源，因此在煤矿中对煤矿粉尘进行实时监测具有重要的意义。本项目提出透射散射光粉尘测量方法，结合全散射和角散射原理，利用全散射光对小颗粒敏感、角散射对大颗粒敏感的特点，建立了光透射散射模型，实现了煤矿宽分布粉尘颗粒粒径的高精度反演。在米氏散射理论基础上，模拟光子在颗粒群中的传输过程，并做统计分析，建立散射和透射光强与光波波长、粉尘颗粒粒径分布、浓度之间的光透射散射数学模型，根据数学模型建立多种颗粒粒径求解的目标函数，如基于Tikhonov正则化理论的目标函数，基于偏振散射光的目标函数等,根据数学模型和目标函数建立多种约束和非约束模式的全散射和角散射相融合的透射散射光颗粒粒径反演算法，如改进的Chahine迭代算法,粒子群算法,人工鱼群算法等，实现宽分布煤矿粉尘的粒径分布及浓度的快速、准确计算。在理论研究的基础上，采用CCD阵列和光谱设备替代传统的环形光强检测装置，实现颗粒散射信号的获取，并应用图像处理技术提取实际的散射光能分布，从而实现多方法同平台宽粒径分布颗粒的同时检测。利用标准颗粒对测试装置进行标定，对不同粒径分布的颗粒群进行实验研究，对不同颗粒粒径计算方法的精度进行对比。不论在理论仿真还是在实验情况下，颗粒粒径测量精度均得到了改进。该项目的研究成果已申请装置发明专利，并将其进行产品化，开发矿用粉尘浓度监测仪，对煤矿粉尘进行实时监控，也可用于工业现场或实验室颗粒粒径检测。