Abstract
In kraft pulp mills, black liquor is concentrated and
burned in recovery boilers to produce steam and power and
to recover pulping chemicals. Black liquor contains a
large amount of alkali compounds, which form ash with low
melting temperatures upon combustion. This causes many
problems in recovery boiler operation, including fouling
of the heat transfer surfaces, plugging of the flue gas
passages, reduction of the heat transfer rate, and
corrosion of the superheater tubes. This paper presents a
model for simulating fine fume particles formed as a
result of condensation of alkali compound vapors in the
recovery boiler.
The modeling method combines CFD modeling, equilibrium
chemistry, and fine particle dynamics in a way that
enables simulation of a full scale three-dimensional
boiler environment. The model has been partially
validated with measurements performed in an operating
recovery boiler. The modeling results, particularly for
the fume particle composition, agree well with the actual
measurements.
| Original language | English |
|---|---|
| Pages (from-to) | 45-53 |
| Number of pages | 9 |
| Journal | Fuel |
| Volume | 129 |
| DOIs | |
| Publication status | Published - 2014 |
| MoE publication type | A1 Journal article-refereed |
Keywords
- kraft recovery boiler
- alkali metal,
- fine particle
- deposition
- computational fluid dynamics