NUMERICAL STUDY ON THE OPTIMAL DESIGN OF SPRAY SYSTEM IN PACKED BED SCRUBBER

충진층식 스크러버의 스프레이 시스템 최적 설계에 대한 수치해석적 연구

  • 고승우 (중앙대학교 대학원 기계공학과) ;
  • 노경철 (중앙대학교 기계공학부) ;
  • 유홍선 (중앙대학교 기계공학부)
  • Published : 2007.03.31

Abstract

This study evaluates the performance of the packed bed scrubber and proposes the optimization of spray system for improvements of collection efficiency. The packed bed scrubber is used primarily in the semiconductor manufacturing process. The mean diameter of entering solid particles in scrubber is the submicron. The impaction between water droplets and solid particles is an important factor in removing the solid particles. Thus, the coverage area of spray system influences on the collection efficiency. The collection efficiency of a single droplet is calculated through the mathematical model and numerical calculations are performed for coverage area for each nozzle type (Droplet diameters: 500, 319.5, $289.5{\mu}m$) and injected directions (0, 15, $30^{\circ}$). In case of nozzle type 3, the collection efficiency of a single droplet is highest but the collection efficiency of spray system has lowest value because the ratio of flow rate between the gas and water is below 0.1. The results show the coverage area ratio is about 85% in the case of nozzle type 3 and downward sirection $15^{\circ}$. It was shown that a coverage area increase by two times than an existing spray system. In simulation of demister, collection efficiency by demister is predicted about 80% and the pressure drop in demister is below 3.5 Pa.

Keywords

References

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