基于光散射法无动力粉尘质量浓度检测技术

Detection technology of unpowered dust concentration based on light scattering method

针对目前煤矿光散射法粉尘质量浓度传感器的易堵塞、维护难问题,提出了一种具有无堵塞、易维护特征的光散射法无动力粉尘质量浓度检测技术并开发光散射法无动力粉尘质量浓度传感器。首先通过分析光散射法粉尘质量浓度检测基本原理与目前光散射法粉尘质量浓度传感器的结构特征,设计了一种由激光器、光电二极管、遮光罩等部分组成的光散射法无动力粉尘质量浓度检测单元,并附上超低信号处理电路,设计了一种光散射法无动力粉尘质量浓度传感器。通过分析外界自然光对光散射法无动力粉尘质量浓度传感器的影响规律,设计一种传感器零点值动态检测的数据处理算法,消除了外界自然的干扰。然后通过分析光散法无动力粉尘质量浓度传感器光散射信号的分布特征,并且确定了光散法无动力粉尘质量浓度传感器检测初始值与实际粉尘质量浓度的数学关系,以粉尘质量浓度低于120 mg/m^(3)采用二次多项式曲线拟合,高于120 mg/m^(3)采用线性拟合的方式,实现了无动力光散射法粉尘质量浓度传感器的精准标定。最后通过试验证明了基于光散射法无动力的粉尘质量浓度传感器低浓度误差低于15%,高浓度误差低于10%。无动力光散射法粉尘质量浓度检测技术检测精度满足标准要求,以无堵塞、易维护的优势增加了光散射法粉尘质量浓度传感器对恶劣环境的适应性,对煤矿粉尘质量浓度的精准在线检测技术的发展提出新思路。

Aiming at the problems of easy clogging and difficult maintenance of the current coal mine light scattering dust concentration sensor,a light scattering unpowered dust concentration detection technology with the characteristics of no clogging and easy maintenance was proposed,and a light scattering unpowered dust concentration sensor was developed.Firstly,by analyzing the basic principle of light scattering dust concentration detection and the structural characteristics of the current light scattering dust concentration sensor,a light scattering non-dy-namic dust concentration detection unit composed of laser,photodiode,light shield and other parts was designed.With the addition of ultra-low signal processing circuits,etc.,a light scattering unpowered dust concentration sensor was designed.By analyzing the influence of external natural light on the sensor,a data processing algorithm for the dynamic detection of sensor point was designed,which eliminates the interference of external nature.Then,by analyzing the distribution characteristics of the light scattering signal of the light-scattering unpowered dust concentration sensor,the mathematical relationship between the initial detection value of the lightscattering unpowered dust concentration sensor and the actual dust concentration was determined.When the dust concentration was lower than 120 mg/m^(3),the quadratic polynomial curve was used for fitting,and the linear fitting method was used for the dust concentration higher than 120 mg/m^(3),which realizes the accurate calibration of the non-dynamic light scattering dust concentration sensor.Finally,it was proved by experiments that the low concentration error of the dust concentration sensor based on the unpowered light scattering method was less than 15%,and the high concentration error was less than 10%.The detection accuracy of dust concentration detection technology by non-dynamic light scattering method meets the standard requirements.With the advantages of non-clogging and easy maintenance,the adaptability of the light scattering dust concentration sensor to harsh environments is increased,and a new idea is proposed for the development of accurate online detection technology of coal mine dust concentration.