마이크로웨이브 플라즈마 버너를 이용한 불화 가스 분해와 화학 및 생물 독가스 제독
ABATEMENT OF FLUORINATED GASES AND ELIMINATION OF CHEMICAL AND BIOLOGICAL WARFARE AGENT BY A MICROWAVE PLASMA BURNER
- 주제(키워드) Purification , Microwave Plasma , Plasma Burner
- 발행기관 아주대학교
- 지도교수 엄환섭
- 발행년도 2006
- 학위수여년월 2006. 8
- 학위명 석사
- 학과 및 전공 일반대학원 분자과학기술학과
- 본문언어 영어
초록/요약
An apparatus for generating flames and more particularly the microwave plasma-burner for generating high-temperature large-volume plasma flame was presented. The plasma-burner is operated by injecting liquid hydrocarbon-fuels into a microwave plasma torch in air discharge and by mixing the resultant gaseous hydrogen and carbon compounds with air or oxygen gas. The microwave plasma torch can instantaneously vaporize and decompose the hydrogen and carbon containing fuels. It was observed that the flame volume of the burner was more than 50 times that of the torch plasma. While the temperature of the torch plasma flame was only 550 K at a measurement point, that of the plasma-burner flame with the addition of 0.025 lpm kerosene and 20 lpm oxygen drastically increased to about 1850 K. A preliminary experiment was carried out, measuring the temperature profiles of flames along the radial and axial directions. A microwave plasma burner was presented as a tool for abating fluorinated compounds (FCs), which are the global warming gases emitted mainly from semiconductor industries. The microwave plasma burner consists of a fuel injector and a reactor connected in series to a microwave plasma torch. In this work, methane (CH4) as a fuel was injected into the microwave plasma torch for generating an enlarged high-temperature plasma flame. A mixture of nitrogen and FC gases was introduced into the fuel injector and oxygen gas was added to the mixture. Abatement of FC gases was conducted in terms of destruction and removal efficiency (DRE) for different nitrogen flow rates. The plasma burner generated at 1.4 kW plasma power and 15 liters per minute (lpm) CH4 achieved DREs > 99.9% for NF3 in 400 lpm nitrogen and SF6 in 120 lpm nitrogen. Also, the plasma burner abated 94.7% of CF4 concentration in 60 lpm nitrogen. Finally, the experimental results presented in this work show that the microwave plasma burner can successfully eliminate FCs discharged from the semiconductor industries. A kerosene microwave plasma burner was presented as a tool for abatement of SF6 and CF4 gases. The plasma burner operates by injecting kerosene as a liquid hydrocarbon fuel into a microwave plasma torch and by mixing the resultant gaseous hydrogen and carbon compounds with air or oxygen gas. The destruction and removal efficiencies of the burner were achieved up to 99.9999% for 0.1 liters per minute SF6 in 120 lpm N2 and 99.3% for 0.05 lpm CF4 in 60 lpm N2, revealing that the plasma burner can effectively eliminate fluorinated gases emitted from the semiconductor industries. An elimination of airborne simulated-chemical and biological warfare agents was carried out by making use of a plasma flame made of atmospheric plasma and a fuel-burning flame, which can purify the interior air of a large volume in isolated spaces such as buildings, public transportation systems, and military vehicles. The plasma flame generator consists of a microwave plasma torch connected in series to a fuel injector and a reaction chamber. For example, a reaction chamber, with the dimensions of a 22 cm diameter and 30 cm length, purifies an airflow rate of 5,000 liters per minute contaminated with toluene, the simulated chemical agent, and soot from a diesel engine, the simulated aerosol for biological agents. Large volumes of purification by the plasma flame will free the mankind from the threat of the airborne warfare agents. The plasma flame may also effectively purify air that is contaminated with volatile organic compounds, in addition to eliminating soot from diesel engines as an environmental application.
more목차
ABSTRACT i
TABLE OF CONTENTS iv
LIST OF FIGURES vii
LIST OF TABLES x
CHAPTER I
INTRODUCTION
A. Research Backgrounds and Motivations 1
1. Electrodeless Microwave Plasma Torch 2
2. Microwave Plasma Burner 5
3. Abatement of Fluorinated Compound Gases 7
4. Decontamination of Chemical and Biological Warfare Agents 15
B. Outline of Text 21
CHAPTER II
THEORY AND CHARACTERISTICS OF MICROWAVE PLASMA TORCH
A. Plasma Parameters 24
B. Microwave Parameters 28
C. Characteristics of Microwave Plasma Torch 30
D. Microwave Plasma Burner 40
CHAPTER III
ABATEMENT OF FLUORINATED COMPOUND GASES BY MICORWAVE PLASMA BURNER
A. Abatement of Fluorinated Compound Gases by a Methane Microwave Plasma Burner 46
1. Experimental Method 46
2. Results and Discussion for Abatement of FC Gases by a Methane Microwave Plasma Burner 52
B. Abatement of SF6 and CF4 by Making Use of a Kerosene
Microwave Plasma Burner 61
1. Experimental Method 61
2. Results and Discussion for Abatement of FC Gases by a Kerosene Microwave Plasma Burner 63
CHAPTER IV
PLASMA FLAME FOR MASS PURIFICATION OF CONTAMINATED AIR WITH CHEMICAL AND BIOLOGICAL WARFARE AGENTS
1. Experimental Apparatus 70
2. Results and Discussion 73
CHAPTER IV
CONCLUSIONS 82
APPENDICES
A. CF4-O2 Plasma Abatement Chemistry 86
B. Additional Reaction and Species for FC Abatement 89
C. NF3 Chemistry 95
REFERENCES 98
PUBLICATIONS
A. Journals 111
B. Patents 113
C. Presentations 114
ABSTRACT (in Korean) 116
