The basic study of the The basic study of the kinetics of black liquor kinetics of black liquor

gasificationgasification

Joko WintokoJoko Wintoko

Department of Forest Product and Chemical EngineeringDepartment of Forest Product and Chemical Engineering

Chalmers University of TechnologyChalmers University of Technology

Schematic of a BLG processSchematic of a BLG process

The aimThe aim

To study the kinetics of black liquor To study the kinetics of black liquor gasificationgasification

Gasification/combustion processGasification/combustion process

Ref: Verril & Wessel (1995)

Plan of the researchPlan of the research

Literature review (ongoing)Literature review (ongoing) Construction of equipment (soon Construction of equipment (soon

finish)finish) Mathematical modeling (ongoing)Mathematical modeling (ongoing) Experimental work (expected start in Experimental work (expected start in

this spring)this spring)

Literature reviewLiterature review

Focusing on:Focusing on:

Phenomena occurs during the black liquor Phenomena occurs during the black liquor combustion/gasificationcombustion/gasification

Mathematical modelsMathematical models

Literature reviewLiterature review

Former model:Former model: Jim FrederickJim Frederick VerrillVerrill & & WesselWessel SaastamoinenSaastamoinen

Forward

Modeling by Jim FrederickModeling by Jim Frederick

Aim: to develop computational model for predicting the Aim: to develop computational model for predicting the combustion times for black liquor droplets in a recovery combustion times for black liquor droplets in a recovery furnace environmentfurnace environment

The controlling resistance is identified by calculating Biot The controlling resistance is identified by calculating Biot number for heat transfer and mass transfer.number for heat transfer and mass transfer.

transferrateexternal

transferrateernalBi

int

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Modeling by Verrill & WesselModeling 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 devolatilizationsodium loss during black liquor drying and devolatilization Amount and composition of fumeAmount and composition of fume

The vapor/gas flow inside the droplet is modeled as flow of The vapor/gas flow inside the droplet is modeled as flow of fluids through porous media.fluids through porous media.

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Modeling by SaastamoinenModeling by Saastamoinen

Aim: calculating the drying, devolatilization and swelling of Aim: calculating the drying, devolatilization and swelling of a black liquor dropleta black liquor droplet

The drying, devolatilization, and swelling is modeled as a The drying, devolatilization, and swelling is modeled as a subsequent process locally. However inside the droplet subsequent process locally. However inside the droplet those two process take place simultaneously.those two process take place simultaneously.

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Literature reviewLiterature review

Kinetics data:Kinetics data: Gasification with CO2Gasification with CO2 Gasification with steam Gasification with steam

Literature reviewLiterature review

Swelling no kineticsSwelling no kinetics Kinetics no swellingKinetics no swelling

Only one studying kinetics + swellingOnly one studying kinetics + swelling

Gasification/combustion processGasification/combustion process

Ref: Verril & Wessel (1995)

ModelingModeling

DryingDrying

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

ModelingModeling

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

EquipmentEquipment

CO2 & COAnalyzer

CH4 & SO2

Analyzer

H2S analyzer

FURNACE

FC

Balance

Power regulator

Data logger for temperature measurement

N2 purging

Video camera

Gas

Gas cooler

Equipment (under construction)Equipment (under construction)

SummarySummary

BLG kinetics studyBLG kinetics study Modeling in FEMLABModeling in FEMLAB

DryingDrying Equipment is finished soonEquipment is finished soon Experimental work latter in this Experimental work latter in this

springspring