Excess Heat from Kraft Pulp Mills: Trade-offs between Internal and External Use in the Case of Sweden - Part 1: Methodology

Excess heat from a kraft pulp mill can be used either internally to increase the level of efficiency in the mill, or externally for example as district heating. This paper presents an approach to investigate the competition between external and internal use through modelling the pulp mill and an energy company (ECO) within the same system boundary. Three different sizes of ECOs with different district heating demands are studied. To investigate the competitiveness of using industrial excess heat as district heating compared with other heat production techniques, the option of investing in excess heat use is introduced, along with the possibility for the ECO to invest in biomass combined heat and power (CHP), waste CHP and natural gas combined cycle (NGCC). To evaluate the robustness of the model, alternative solutions are identified and will be used as a comparison to the optimal solutions. The model has been verified by comparing the results with previous studies concerning kraft pulp mills and with related studies regarding district heating and real ECOs. Finally, the approach presented in this part of the study will be used in the second part in order to investigate the trade-off between internal and external use of excess heat under different future energy market scenarios.

[1]  Mats Söderström,et al.  Towards cooperation in industrial symbiosis: considering the importance of the human dimension , 2005 .

[2]  Peter Sandberg,et al.  Driving forces and obstacles with regard to co-operation between municipal energy companies and process industries in sweden , 2006 .

[3]  Alemayehu Gebremedhin.  The role of a paper mill in a merged district heating system , 2003 .

[4]  Thore Berntsson,et al.  Increased capacity in kraft pulp mills: Lignin separation and reduced steam demand compared with recovery boiler upgrade , 2006 .

[5]  Bahram Moshfegh,et al.  An integrated chemical pulp and paper mill: Energy audit and perspectives on regional cooperation , 2006 .

[6]  Simon Harvey.  Scenarios for evaluating energy efficiency measures in industrial energy systems , 2004 .

[7]  B. G. Karlsson,et al.  MIND optimization reduces the system cost at a refinery , 1994 .

[8]  Louise Trygg,et al.  SWEDISH INDUSTRIAL AND ENERGY SUPPLY MEASURES IN A EUROPEAN SYSTEM PERSPECTIVE , 2006 .

[9]  Bahram Moshfegh,et al.  Modelling and optimization of district heating and industrial energy system - An approach to a locally deregulated heat market , 2004 .

[10]  Åsa Marbe.  New Opportunities and System Consequences for Biomass Integrated Gasification Technology in CHP Applications , 2005 .

[11]  Sven Werner,et al.  Combined heat and power in the Swedish district heating sector--impact of green certificates and CO2 trading on new investments , 2006 .

[12]  Thore Berntsson,et al.  Exporting lignin or power from heat-integrated kraft pulp mills: A techno-economic comparison using model mills , 2006 .

[13]  Thore Berntsson,et al.  Heat integration opportunities in average Scandinavian kraft pulp mills: Pinch analyses of model mills , 2006 .