Author | Sarawut Jetinai |
Call Number | AIT Thesis no. PP-99-14 |
Subject(s) | Kraft paper industry
|
Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of
Engineering, School of Environment, Resources and Development |
Publisher | Asian Institute of Technology |
Abstract | The study was set up to investigate the influence of electrostatic precipitator (ESP) ash on
the distribution of chloride and potassium in modern kraft recovery boiler. Both chloride
and potassium, which enter a mill with wood raw material, lower the melting point of
fume or ash, causing deposits and plugging the flue gas passage, and also accelerating
corrosion. Advance Agro Public Company Limited, the first pulp and paper integrated
mill in Thailand has conducted the study. Under the variation in two set of conditions:
ESP ash recycling and removing, the elements in concern such as sodium, potassium and
chloride presented in black liquor, smelt and ESP dust were quantified as well as sulfate
in black liquor and flue gas.
Both the chloride and potassium contents in black liquor solids of 1.5% and 5.1 %(wt),
respectively, in condition of ESP ash recycling considered as normal operation, are
higher than the typical values of about 3 times. The predicted sticky temperature of ESP
dust is about 520°C corresponding to chloride and potassium enrichments in the dust both
of around 20% mole. With operating superheated steam temperature of about 450 °C,
plugging is likely occmred.
Chloride and potassium enrichment factors of ESP dust are 4.7 and 1.5, showing less
variation to the typical values of around 3 and 1.6, respectively. Chloride and potassium
enrichment of 20.0% and 20.2% mole in case of ESP ash recycling show insignificant
difference to that of ESP ash removing of 18.3% and 18.4% mole, respectively. To the
lower extent of chloride and potassium enrichments, ESP ash disposing period is required
long run up to month. The mill situation contains relatively high level of chloride and
potassium, but not critically high. |
Year | 1999 |
Type | Thesis |
School | School of Environment, Resources, and Development (SERD) |
Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
Academic Program/FoS | Pulp and Paper Technology (PP) |
Chairperson(s) | Malinen, Raimo 0.; |
Examination Committee(s) | Kiiskila, Erkki ;Kolehmainen, Heikki; |
Scholarship Donor(s) | Advance Agro Public Company Limited; |
Degree | Thesis (M.Eng.) - Asian Institute of Technology, 1999 |