The basic study of the kinetics of black liquor gasification Joko Wintoko Department of Forest Product and Chemical Engineering Chalmers University of Technology

Schematic of a BLG process

The aim To study the kinetics of black liquor gasification To study the kinetics of black liquor gasification

Gasification/combustion process Ref: Verril & Wessel (1995)

Plan of the research Literature review (ongoing) Literature review (ongoing) Construction of equipment (soon finish) Construction of equipment (soon finish) Mathematical modeling (ongoing) Mathematical modeling (ongoing) Experimental work (expected start in this spring) Experimental work (expected start in this spring)

Literature review Focusing on: Phenomena occurs during the black liquor combustion/gasification Phenomena occurs during the black liquor combustion/gasification Mathematical models Mathematical models

Literature review Former model: Former model: Jim Frederick Jim Frederick Jim Frederick Jim Frederick Verrill & Wessel Verrill & Wessel Verrill & Wessel Verrill & Wessel Saastamoinen Saastamoinen Saastamoinen Forward

Modeling by Jim Frederick Aim: to develop computational model for predicting the combustion times for black liquor droplets in a recovery furnace environment Aim: to develop computational model for predicting the combustion times for black liquor droplets in a recovery furnace environment The controlling resistance is identified by calculating Biot number for heat transfer and mass transfer. The controlling resistance is identified by calculating Biot number for heat transfer and mass transfer. Back

Modeling by Verrill & Wessel Application of modeling result to study the laboratory data: Application of modeling result to study the laboratory data: sodium loss during black liquor drying and devolatilization sodium loss during black liquor drying and devolatilization Amount and composition of fume Amount and composition of fume The vapor/gas flow inside the droplet is modeled as flow of fluids through porous media. The vapor/gas flow inside the droplet is modeled as flow of fluids through porous media. Back

Modeling by Saastamoinen Aim: calculating the drying, devolatilization and swelling of a black liquor droplet Aim: calculating the drying, devolatilization and swelling of a black liquor droplet The drying, devolatilization, and swelling is modeled as a subsequent process locally. However inside the droplet those two process take place simultaneously. The drying, devolatilization, and swelling is modeled as a subsequent process locally. However inside the droplet those two process take place simultaneously. Back

Literature review Kinetics data: Kinetics data: Gasification with CO2 Gasification with CO2 Gasification with steam Gasification with steam

Literature review Swelling no kinetics Swelling no kinetics Kinetics no swelling Kinetics no swelling Only one studying kinetics + swelling Only one studying kinetics + swelling

Gasification/combustion process Ref: Verril & Wessel (1995)

Modeling Drying Assumptions: Water evaporation takes place only on the droplet surface. Heat transfer inside the droplet is only due to conduction. Mass transfer inside the droplet is only due to diffusion nitrogen gas flow water evaporation black liquor droplet

Modeling Result of modeling & comparing with the data from literature Result of modeling & comparing with the data from literature

Equipment CO 2 & CO Analyzer CH 4 & SO 2 Analyzer H 2 S analyzer FURNACE FC Balance Power regulator Data logger for temperature measurement N2 purging Video camera Gas Gas cooler

Equipment (under construction)

Summary BLG kinetics study BLG kinetics study Modeling in FEMLAB Modeling in FEMLAB Drying Drying Equipment is finished soon Equipment is finished soon Experimental work latter in this spring Experimental work latter in this spring