Abstract
More than 900 papers related to organosolv pulping have been
reviewed in this thesis. From the information included in those
papers it can be concluded that organosolv pulping processes are
still in a developing stage and are not yet ready to seriously threat
the position of the kraft process as the main pulp manufacturing
process in the world.
Distillation seems to be the main alternative as the process
for recovering the solvent in organosolv pulping. A good reason
for this is that using simple distillation no potentially harmful
components are introduced to the process.
The effect of feed composition on the operation of a separation
sequence in an organosolv process using aqueous formic and acetic
acids and corresponding peroxyacids was studied. When simple distillation
was used as the separation method the effect was found to be significant.
The no ideal nature of the formic acid-acetic acid-water mixture,
which separation was studied, makes the ternary composition space
to divide into four distillation regions. Which region the feed
is located in, obviously determines the economy of the distillation
sequence.
Shortcut calculation methods cannot be recommended to be
used for designing a distillation sequence for the ternary mixture
studied, but they give useful information for the comparison of
such sequences. They were used to choose a limited number of alternatives
for studies with rigorous calculation methods.
Minimum work of separation can also be used to make a satisfying
estimate for the relative easiness of separation of the formic acid-acetic
acid-water mixture.
Thermal integration using pinch technology was also tested
and found very useful for decreasing the thermal energy consumption
of distillation processes.
Thermodynamic efficiencies for separating the formic acid-acetic
acid-water mixture by simple distillation were estimated. They were
found to be lower than the average value for distillation presented
in literature.
| Identifer | oai:union.ndltd.org:oulo.fi/oai:oulu.fi:isbn951-42-5661-1 |
| Date | 18 May 2000 |
| Creators | Muurinen, E. (Esa) |
| Publisher | University of Oulu |
| Source Sets | University of Oulu |
| Language | English |
| Detected Language | English |
| Type | info:eu-repo/semantics/doctoralThesis, info:eu-repo/semantics/publishedVersion |
| Format | application/pdf |
| Rights | info:eu-repo/semantics/openAccess, © University of Oulu, 2000 |
| Relation | info:eu-repo/semantics/altIdentifier/pissn/0355-3213, info:eu-repo/semantics/altIdentifier/eissn/1796-2226 |
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