Additional revenue opportunities in pulp mills and their impacts on the kraft process
Hamaguchi, Marcelo (2013-12-18)
Väitöskirja
Hamaguchi, Marcelo
18.12.2013
Lappeenranta University of Technology
Acta Universitatis Lappeenrantaensis
Julkaisun pysyvä osoite on
https://urn.fi/URN:ISBN:978-952-265-541-7
https://urn.fi/URN:ISBN:978-952-265-541-7
Tiivistelmä
Although the concept of multi-products biorefinery provides an opportunity to meet the
future demands for biofuels, biomaterials or chemicals, it is not assured that its
implementation would improve the profitability of kraft pulp mills. The attractiveness
will depend on several factors such as mill age and location, government incentives,
economy of scale, end user requirements, and how much value can be added to the new
products. In addition, the effective integration of alternative technologies is not
straightforward and has to be carefully studied. In this work, detailed balances were
performed to evaluate possible impacts that lignin removal, hemicelluloses recovery
prior to pulping, torrefaction and pyrolysis of wood residues cause on the conventional
mill operation. The development of mill balances was based on theoretical
fundamentals, practical experience, literature review, personal communication with
technology suppliers and analysis of mill process data.
Hemicelluloses recovery through pre-hydrolysis of chips leads to impacts in several
stages of the kraft process. Effects can be observed on the pulping process, wood
consumption, black liquor properties and, inevitably, on the pulp quality. When lignin is
removed from black liquor, it will affect mostly the chemical recovery operation and
steam generation rate. Since mineral acid is used to precipitate the lignin, impacts on the
mill chemical balance are also expected. A great advantage of processing the wood
residues for additional income results from the fact that the pulping process, pulp
quality and sales are not harmfully affected. For pulp mills interested in implementing
the concept of multi-products biorefinery, this work has indicated possible impacts to be
considered in a technical feasibility study.
future demands for biofuels, biomaterials or chemicals, it is not assured that its
implementation would improve the profitability of kraft pulp mills. The attractiveness
will depend on several factors such as mill age and location, government incentives,
economy of scale, end user requirements, and how much value can be added to the new
products. In addition, the effective integration of alternative technologies is not
straightforward and has to be carefully studied. In this work, detailed balances were
performed to evaluate possible impacts that lignin removal, hemicelluloses recovery
prior to pulping, torrefaction and pyrolysis of wood residues cause on the conventional
mill operation. The development of mill balances was based on theoretical
fundamentals, practical experience, literature review, personal communication with
technology suppliers and analysis of mill process data.
Hemicelluloses recovery through pre-hydrolysis of chips leads to impacts in several
stages of the kraft process. Effects can be observed on the pulping process, wood
consumption, black liquor properties and, inevitably, on the pulp quality. When lignin is
removed from black liquor, it will affect mostly the chemical recovery operation and
steam generation rate. Since mineral acid is used to precipitate the lignin, impacts on the
mill chemical balance are also expected. A great advantage of processing the wood
residues for additional income results from the fact that the pulping process, pulp
quality and sales are not harmfully affected. For pulp mills interested in implementing
the concept of multi-products biorefinery, this work has indicated possible impacts to be
considered in a technical feasibility study.
Kokoelmat
- Väitöskirjat [1036]