Estimation of Coal Devolatilization Modeling Parameters from Thermogravimetric and Time-resolved Soft Ionization Mass Spectrometric Data

Nowadays i t i s w i d e l y recogn ized t h a t t h e i n i t i a l p y r o l y s i s s t e p i n coa l convers ion processes has a p ro found e f f e c t on t h e y i e l d and d i s t r i b u t i o n o f end produc ts such as c o a l d e r i v e d l i q u i d s , gases, coke, o r p o l l u t a n t emiss ions . Two general approaches f o r model ing coa l p y r o l y s i s r e a c t i o n s can be d i s t i n g u i s h e d , namely: ( a ) phenomenological model ing and ( b ) chemical mode l ing [l]. The phenomenological model ing approach i s u s e f u l i n c o n v e r s i o n processes such as h i g h tempera ture g a s i f i c a t i o n where d e t a i l e d chemical i n f o r m a t i o n may be advantageous b u t i s p robab ly n o t ind ispensab le . Other convers ion processes, however, e.g., l i q u e f a c t i o n and h y d r o p y r o l y s i s , may r e q u i r e more d e t a i l e d chemical i n f o r m a t i o n t o p r e d i c t t h e d i s t r i b u t i o n o f f i n a l p r o d u c t s [2]. Whether p y r o l y s i s ( " d e v o l a t i l i z a t i o n " ) models f o r p u l v e r i z e d coa l combust ion processes r e q u i r e d e t a i l e d i n f o r m a t i o n on coa l s t r u c t u r e and r e a c t i v i t y o r can be based p r i m a r i l y on a phenomenological approach i s s t i l l a m a t t e r o f c o n s i d e r a b l e debate [3 ] .