Development Of Compact Rainbow Refraction Measuring Device And Application Of Multi-phase Reaction Droplet For Desulfurization

Spray droplet is significant form of gas-liquid two-phase reaction,which has large specific surface area and is widely used in production and daily life.The accurate measurement of spray droplet parameters is of great significance for understanding the mechanism of gas-liquid two-phase reaction and guiding industrial production.Rainbow measurement technology is attracting more and more attention because of its advantages of on-line in-situ measurement of temperature?composition?of spray droplets.In this paper,aiming at the difficulty of rainbow measurement technology in engineering application,an integrated rainbow refractometer with compact structure and adjustable laser incidence angle is designed.A drop-on-demand droplet generator is developed.The experimental study of single droplet measurement is carried out.The application potential of rainbow refractometry in power plant desulfurization tower is explored.The following three aspects are studied.A compact rainbow refractometer is designed and developed.The problems of the existing rainbow optical system applied in the field environment are analyzed,and the optical system is improved.Based on the improved optical system,an integrated rainbow refractometer with small size,portable,sealed and stable performance is designed and developed.The rainbow refractometer has the function of tunable laser incidence angle.It can directly change the incidence angle of laser by adjusting the rotation table,and keep the location of measuring points unchanged,thus increasing the measuring range of refractive index,which enables the rainbow refractometer to measure the spray of different refractive index conveniently.And the calibration process is simplified.A series of experimental tests on rainbow refractometer are carried out.The rainbow refractometer is used to measure the deionized water spray.The results show that the measurement accuracy of the rainbow refractometer is2?10^-4.The refractive index of water-ethanol two component spray at different mixing ratios is measured and compared with literature data.The experimental results are in good agreement with the literature data.Finally,the axial refractive index distribution of ethanol spray was measured,and the temperature distribution was calculated.The heat transfer in the spray evaporation process was analyzed.Standard rainbow of single droplets was measured with the rainbow refractometer.A drop-on-demand droplet generator is developed.The formation process of single droplet using deionized water as spraying liquid is photographed with a high-speed camera.The droplet size and velocity change is calculated.The change of droplet velocity between upward and downward injection of ethanol was compared.The refractive index of ethanol droplets at different heights is measured by rainbow refractometer.The change of the refractive index of ethanol droplets in the process of mass and heat transfer with the outside is summarized.The test results show that the rainbow refractometer can accurately capture the standard rainbow of single droplets and retrieve the refractive index.The rainbow refractometer is applied to the multiphase reaction of spray desulfurization.Firstly,the feasibility of estimating the ionic composition and concentration in desulfurization slurry by rainbow measurement technology is analyzed.The change of refractive index of various ions with concentration is compared.The calculation method of refractive index of mixed ion solution is verified by experiments.The general method of obtaining the concentration relationship of each ion component in mixed ion solution is given.The Rainbow measurement technology is analyzed in desulfurization waste liquid.Then,the experimental system of desulfurization in spray tower is built,and the refractive index change of desulfurizer during desulfurization reaction is measured in situ by rainbow refractometer.