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Gothenburg, Sweden

Johansson D.,Goteborg Energi AB | Franck P.-T.,Goteborg Energi AB | Berntsson T.,Chalmers University of Technology
Energy | Year: 2012

In this paper, the global CO 2 effect of integrating different biomass gasification concepts to meet an increasing demand of hydrogen in an oil refinery is examined and presented in comparison with a conventional steam reformer. The studied refinery is a hydro skimming refinery with a future hydrogen deficit of 16,000Nm 3/h. Three gasification concepts are considered: Entrained Flow (EF), Circulated Fluidised Bed (CFB) and Double Bed (DB). The system analysis is made with respect to global CO 2 emissions and primary energy use. The results show that if biomass is considered as an unlimited resource (i.e. sufficient biomass is considered to be available to substitute for all fossil fuels in society), biomass gasification concepts have a potential to reduce CO 2 emissions. The EF case shows the largest reduction potential. However, if biomass is considered as a limited resource (i.e. increased use of biomass at the refinery will lead to increased use of fossil fuel elsewhere in society), all concepts show an increase of CO 2 emissions. Here, the CFB gasifier shows lowest increase of CO 2 emission. The CO 2 effect of the different alternatives shows sensitivity to assumptions regarding alternative biomass user. © 2011 Elsevier Ltd. Source

Svensson E.,Chalmers University of Technology | Eriksson K.,Goteborg Energi AB | Wik T.,Chalmers University of Technology
Biofuels, Bioproducts and Biorefining | Year: 2015

The implementation of a biorefinery concept through the integration of new biomass conversion processes with existing industrial plants offers a potential for high overall biomass-to-product efficiencies and cost-effective production. To reach this potential, a high degree of process integration is essential. This implies that there will be strong interconnections between the different processing units in the original plant and the new biorefinery process, and thereby a risk of operability difficulties. Consequently, there is a need to consider operational objectives, together with economic and environmental ones in biorefinery integration design problems. This paper focuses on the operability of an industrial plant that is retrofitted with a new biorefinery process. The existing industrial plant is considered to be an energy-intensive, mature, commodity-producing plant and retrofit of this plant is necessary for enabling efficient integration and synergy effects of co-locating the biorefinery process with the existing process, instead of building a stand-alone greenfield plant. A wide range of operability issues associated with the integration of the biorefinery is considered, including flexibility, controllability, and reliability. The main issues that affect the operability when integrating a new biorefinery process to an existing industrial plant are investigated. Core operability issues to consider in the design and evaluation of future biorefinery concepts are highlighted and opportunities for further research and methodology development activities are identified. © 2014 Society of Chemical Industry and John Wiley & Sons, Ltd. Source

Isaksson J.,Chalmers University of Technology | Asblad A.,Goteborg Energi AB | Berntsson T.,Chalmers University of Technology
Biomass and Bioenergy | Year: 2013

Integration of biomass gasification with a pulp and paper mill is a possible route to create more value-added products. This route facilitates, for example, more advanced electricity generation and production of biomass based transportation fuels or chemical feedstock. Each unit operation in such a process affects overall efficiency as well as possibilities for process integration. In this paper, the impact of different dryer types in a biomass gasification combined cycle (BIGCC) has been evaluated in terms of efficiency and economic performance. The BIGCC was sized so that the excess heat would replace the current steam production from bark and oil. The results show that the dryer type can have a significant impact on economic performance and efficiencies. A BIGCC with an integrated belt dryer, utilizing excess heat to heat the drying air from the mill, can result in electrical efficiencies of up to around 40%, while e.g. a steam dryer can reach 36-37%. Choice of oxidant, air or oxygen, in the gasifier affects both capital and operational cost. Air was proven to be the most cost efficient solution for the cases evaluated in this study. The investment of around 100 to 140 million Euros for a BIGCC facility is profitable for most evaluated cases for an annuity factor of 0.1, while the net annual profit is negative for most cases when the annuity factor was increased to 0.2, even when including financial support for renewable electricity. © 2013 Elsevier Ltd. Source

Paulinder J.,Goteborg Energi AB
IET Conference Publications | Year: 2013

With the new network regulation model in Sweden, the financial reality for the network utilities has become tougher. It is more important than ever to ensure that the right investments are made. Reliability analysis is a tool to improve the basis for decision making when planning an investment. It can be seen as a way of quantifying the quality of supply. The result can then, together with economical and other technical aspects, form a thorough base for the decision-making process. Goteborg Energi Nat AB has recently introduced reliability analysis as a tool in network planning. The method is used to compare different investment alternatives, and to ascertain whether a planned investment will result in the expected improvement in quality of supply. This paper shows, using a practical example, how the theories of reliability analysis can be applied, what land of results to expect and how these results can be implemented. Source

Johansson D.,Chalmers University of Technology | Berntsson T.,Chalmers University of Technology | Franck P.-A.,Goteborg Energi AB
International Journal of Environment and Sustainable Development | Year: 2014

The oil refining industry is facing harder policies on renewable content in its products. One way to meet this is to produce diesel and gasoline from gasification of biomass via a Fischer-Tropsch (FT) synthesis. In this paper, heat integrating a biomass-to-FT syncrude process with a refinery is compared to a stand-alone biomass-to-FT syncrude process, in terms of the consequences for GHG emissions and energy balances. The upgrading of the FT syncrude is in both cases accomplished at the refinery, in the existing units or in new units. The studied system includes a circulating fluidised-bed biomass gasifier with a biomass input of 500 MW (50% moisture content) and a complex refinery with a crude oil capacity of 11.4 Mt/y. The integrated FT syncrude production shows the greatest potential for reductions in GHG emissions. Still, the GHG emission mitigation potential of using biomass for FT fuel production is smaller than co-firing biomass with coal in coal power plants. Copyright © 2014 Inderscience Enterprises Ltd. Source

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