Optical measurement method of non-spherical particle size and concentration based on high-temperature melting technique.

• The theoretical dynamic model of optical measuring volume (OMV) with gas temperature is established. • The application condition of OPC is extended to 650 °C. • An optical measurement method of non-spherical particle based on high temperature melting technique is proposed. Optical particle counter (OPC) is always used to measure particles in high-temperature gas pipelines through gas cooling, leading to the original molten droplets condensing into irregular solid particles. To solve the problem, an optical measurement method of non-spherical particle size and concentration based on high-temperature melting technique is proposed. By establishing the theoretical dynamic model of optical measuring volume (OMV) of commercial OPC (Welas 3000, PALAS GMBH, Germany) with changing gas temperature and studying the thermal expansion characteristics of aerosol conduit, the influence of gas temperature on OPC optical sensor is analyzed, and OPC is applied at 650 °C. On this foundation, irregular glass particles are melted into spherical shape by high-temperature melting technique to realize the optical measurement of particle size and mass concentration. By comparing the online and off-line results of mass concentration, the deviation between them is less than 5%, verifying the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]