Study of Submicron Particle Removal by a Venturi Scrubber Via Heterogeneous Nucleation
|Keywords:||異相凝核增長;文氏洗滌器;次微米微粒;heterogeneous nucleation;Venturi scrubber;submicron particles|
A Venturi scrubber to remove submicron particles in the exhaust is investigated in this study. Using high temperature and saturated steam to mix with normal temperature gas, which was composed of NaCl particles, those submicron particles would grow in particle diameter by heterogeneous nucleation, so removal of submicron particles is possible. In the traditional experiment of Venturi scrubber (without adding steam), the particle diameter for lowest removal efficiency is about 20nm, where the efficiency is only about 20% in the operating condition for the flowrate of normal temperature gas and the liquid to gas ratio are 400 lpm and 2.5 l/m3, respectively. However, the removal efficiency is greater than theoretical prediction. When particles grow by heterogeneous nucleation, the removal efficiency of 20nm particles is promoted to the range of 62% to 71% in the operating condition of 200 lpm and 2.5 l/m3. In this study, the removal efficiency is between 60% to 90%, and the pressure drop is only 9.3 in. H2O. The removal efficiency is above 55% for the computer simulation of mixing ratio is as low as 0.0046. In this simulation, total energy consumed is used to heterogeneous nucleation of submicron NaCl particles, so there is no waste heat generated. This method can be applied to remove submicron particles for industrial application after improving the mixing for saturated steam and exhaust.
|Appears in Collections:||Thesis|