水体小粒径悬浮物粒度低位异面扫描光散射测量方法研究  

Study on method of low position out-of-plane scanning light scattering of small-particle-sized suspended solids in water

作　　者：刘灯奎 殷高方 石朝毅[2] 贾仁庆 石一鸣 漆艳菊 夏蒙 甘婷婷 杨瑞芳 赵南京 LIU Dengkui;YIN Gaofang;SHI Chaoyi;JIA Renqing;SHI Yiming;QI Yanju;XIA Meng;GAN Tingting;YANG Ruifang;ZHAO Nanjing(Key Laboratory of Environmental Optics and Technology,Anhui Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Hefei 230031,China;Hefei University,Hefei 230601,China;School of Environmental Science and Optoelectronic Technology,University of Science and Technology of China,Hefei 230026,China;Information Materials and Intelligent Sensing Laboratory of Anhui Province,Institutes of Physical Science and Information Technology,Anhui University,Hefei 230601,China)

机构地区：[1]中国科学院安徽光学精密机械研究所中国科学院环境光学与技术重点实验室,安徽合肥230031 [2]合肥学院,安徽合肥230601 [3]中国科学技术大学环境科学与光电技术学院,安徽合肥230026 [4]安徽大学物质科学与信息技术研究院安徽省信息材料与智能感知实验室,安徽合肥230601

出　　处：《光学技术》2022年第5期548-553,共6页Optical Technique

基　　金：中国科学院科研仪器设备研制项目(YJKYYQ20190050);安徽省科技重大专项(202003a07020007);中国科学院环境光学与技术重点实验室开放基金(2005DP173065-2020-01);安徽省高校优秀青年人才支持计划项目(gxyq2021229)。

摘　　要：静态散射光蕴含颗粒尺寸的特征信息,因此静态光散射法是快速测量水体悬浮物粒度的有效手段。然而由于颗粒侧向和后向散射光微弱,不易探测;前向散射受艾里斑影响,存在测量盲区,导致静态光散射法的小颗粒粒度测量精度不足。提出水体小粒径悬浮物粒度低位异面扫描光散射测量方法,以光电倍增管为探测器,采用多角度连续扫描方式探测颗粒的光散射信息:通过缩短探测器到样品池距离,提高相同角分辨率下的散射光强度,提升侧向和后向散射光探测灵敏度;将探测器偏离激发光轴,避开艾里斑盲区,在不改变前角小角度测量精度条件下,实现前向大角度散射光探测。在此基础上,结合米散射模型,实现小粒径悬浮物粒度测量。不同粒度样品实验表明,方法能准确测量350nm至2μm范围内颗粒的粒度,2μm、1.5μm、500nm和350nm标物D的测量相对误差均不超过5.61%,均低于标物不确定度的相对误差,且优于实验室内激光粒度仪的测量结果。Static light scattering contains characteristic information of particle size, so static light scattering method is an effective means to measure the particle size of suspended matter in water body rapidly. However, the measurement accuracy of the static light scattering method for small particle size measurement is insufficient because the lateral and backward scattered light of particles is weak and not easily detected, and the forward scattering is affected by the Airy spot and there is a blind area for measurement. A low-level anisotropic scanning light scattering measurement method for small particle size suspensions in water is proposed, using a photomultiplier tube as the detector and a multi-angle continuous scanning method to detect the light scattering information of particles: by shortening the distance from the detector to the sample cell, the intensity of scattered light at the same angular resolution is increased, and the sensitivity of lateral and backward scattered light detection is improved;by deviating the detector from the excitation optical axis By avoiding the blind area of Airy spot, the forward large-angle scattered light detection can be achieved without changing the precision of the small-angle measurement of the front angle. On this basis, the method is combined with the meter scattering model to achieve the particle size measurement of small particle size suspensions. Experiments on different particle size samples show that the method can accurately measure the particle size of particles in the range of 350 nm to 2μm, and the relative errors of measurement of D50 for 2μm, 1.5μm, 500 nm and 350 nm specimens do not exceed 5.61%, all of which are lower than the relative errors of specimen uncertainty, and are better than the measurement results of laser particle size meters in the laboratory.

关 键 词：光学测量 小粒径 悬浮颗粒物 粒度测量 静态光 低位异面测量 

分 类 号：TH741[机械工程—光学工程]