Experimental Study on Atomizing and Reaction Performance of Pressure Swirl Nozzles in Ethoxylation Reactor

Spray Tower Loop Reactors is one of the most advanced ethoxylation reactors in the world. The special pressure swirl nozzles are the core component and important for production efficiency and product quality. A test rig was established, which was divided into four parts: spray system, laser measurement system, photographic system and flux distribution test system. An experimental study on the atomizing performances was conducted, including discharge coefficient, spray cone angle, spray flux distribution, Sauter mean droplets size and droplets size distribution. According to the measurement data, the correlation of volume flow rate, discharge coefficient, spray cone angle and Sauter mean droplets size versus pressure drop were respectively gained. The spray flow distributions of all measured nozzles are classified as a unimodal、bimodal and trimodal distribution due to the different structure. And the experimental Probability Density Function (PDF) of the droplets size was gained by a split-type spray laser droplets size analyzer and compared with five empirical distributions. The log-hyperbolic distribution has a most agreement with the measured PDF. At same time, reaction performance of the special nozzles was measured in the industrial STLR ethoxylation reactor. It is indicated that Sauter mean diameter determines the number of EO and the width of droplets size distribution determines the width of the molecular weight distributions. The present paper exhibits the measurement way and outcomes of spray characteristics of the nozzles in ethoxylation reaction and it is instructive for the optimization design of SPLT ethoxylation reaction.