Reaction Rate Analysis of Combustion for Indonesian Coal Char Applied by External/Internal Diffusion

Autor: Ryang-Gyoon Kim, Kwang-Il Ryu, Ze-Lin Wu, Chung-Hwan Jeon, Chan-Won Hwang
Rok vydání: 2014
Předmět:
Zdroj: Korean Chemical Engineering Research. 52:133-140
ISSN: 0304-128X
DOI: 10.9713/kcer.2014.52.1.133
Popis: 본 연구의 목적은 국내 화력발전소에서 사용중인 인도네시아 석탄촤의 연소반응율을 연구하는 것이다. 석탄촤의 반응율은 External, Internal effectiveness factor를 고려하여 입자 내부 및 외부확산을 정량적으로 정리하였으며, Randompore model을 사용하여 탄소변환율에 따른 입자내부비표면적의 변화를 반영하였다. 가열 및 측정이 가능한 WHR(WireHeating Reactor)를 활용하여 반응시간을 측정함으로써 석탄촤의 반응율을 도출하였고 BET(Brunauer-Emmett-Teller)및 TGA(Thermo-Gravimetric Analysis) 장비를 활용하여 석탄촤의 물리적인 특성인 내부비표면적과 Random pore model의 구조변수(ψ)를 측정하였다. 석탄 종에 따른 활성화에너지 및 빈도인자를 도출하기 위해 아역청탄인 BARAMULTI,ENERGYMAN, AGM탄을 사용하였다. 본 연구 결과에서 External, Internal effectiveness factors를 통해 확산에 따른kinetics를 비교한 결과 외부 확산 보다 내부 확산의 영향이 지배적임을 확인하였다. 최종적으로 내부 및 외부 확산에대한 영향을 고려한 3종의 석탄촤 Intrinsic kinetics의 활성화에너지는 110~118 kJ/mol의 값을 보였다.Abstract −The experiment was designed to compare the char combustion kinetics of pulverized Indonesia coals com-monly utilized in Korea power plants. The reaction rate of coal char has been formulated using the external and internaleffectiveness factors to describe the diffusion effect quantitatively. The Random Pore Model (RPM) was used for apply-ing internal specific surface area as a function of carbon conversion ratio. Reaction rate was obtained from reaction timeusing the Wire Heating Reactor (WHR) which can heat and measure the char particle temperature at the same time. BETand TGA were used to obtain physical properties such as internal specific surface area and structural parameter. Threekinds of Indonesia Sub-bituminous coals “BARAMULTI, ENERGYMAN, AGM” were used in order to derive the acti-vation energy and pre-exponential factor. The results of this study showed that the effect of internal diffusion than that ofexternal diffusion is the dominant as comparison of kinetics was reflected in external and internal effectiveness factors.For three kinds of coal char, finally, activation energy of intrinsic kinetics indicates 110~118 kJ/mol. Key words: Coal Char, Reaction Rate, Kinetics, WHR, RPM
Databáze: OpenAIRE