Added value from biomass by broader utilization of fuels and CHP plants

The present work, where additional value-creating processes in existing combined heat and power (CHP) structures have been examined, is motivated by a political- and consumer-driven strive towards a bioeconomy and a stagnation for the existing business models in large parts of the CHP sector. The research is based on cases where the integration of flash pyrolysis for co-production of bio-oil, co-gasification for production of fuel gas and synthetic biofuels as well as leaching of extractable fuel components in existing CHP plants have been simulated. In particular, this work has focused on the CHP plants that utilize boilers of fluidized bed (FB) type, where the concept of coupling a separate FB reactor to the FB of the boiler forms an important basis for the analyses. In such dual fluidized bed (DFB) technology, heat is transferred from the boiler to the new rector that is operating with other fluidization media than air, thereby enabling other thermochemical processes than combustion to take place. The result of this work shows that broader operations at existing CHP plants have the potential to enable production of significant volumes of chemicals and/or fuels with high efficiency, while maintaining heat supply to external customers. Based on the insight that the technical preconditions for a broader operation are favourable, the motivation and ability among the incumbents in the Swedish CHP sector to participate in a transition of their operation towards a biorefinery was examined. The result of this assessment showed that the incumbents believe that a broader operation can create significant values for their own operations, the society and the environment, but that they lack both a strong motivation as well as important abilities to move into the new technological fields. If the concepts of broader production are widely implemented in the Swedish FB based CHP sector, this can substantially contribute in the transition towards a bioeconomy.

Höjdbestämningsmetoder vid upprättande av nybyggnadskartor : Jämförelse mellan nätverks-RTK och trigonometrisk höjdmätning

Levelling and trigonometric height measurements are the methods that are mostly used today for height determination, as the standard error with these methods is in the magnitude of millimeters, as long as the view length is less than 50 m. When creating a new construction map the requirement on standard error differ from 1 (Fredriksson, 2011) to 10 cm (www.arvidsjaur.se) depending on which municipality it concerns. When using network RTK for measuring, the accuracy in height can fall below 3 cm when the conditions are optimal. The purpose of this paper is to investigate if network RTK can be used as an alternative to determinate height when accuracy under 10 cm is requested. Five points at locations with different conditions for accuracy got their height determined with the three methods mentioned above. Positional accuracy was formed for each point and method. The result from levelling was used as reference for the calculations. To compare the result with the requirements extended standard uncertainty, 2covering 95 %, was used. The result from trigonometric height measurement shows a position accuracy of 4 mm. From the network RTK, the points that were positioned without interference got a positional accuracy of 3.3 to 5.5 cm, while the points that were influenced by their environment, multipath interference and obstructions, got a positional accuracy of 123.3 cm and 234.4 cm. Positional accuracy of this method became 127.4 cm. The result from the height determination with network RTK shows big difference in accuracy for the different points. The conclusion is that network RTK measurement would not be a sufficiently accurate height determination method for preparation of a new construction map in an area similar to the one used for this test. Conversely, a construction map drawn up in an open area free from interference obstacles the results show that the network RTK is an approved method for determining height, depending on the requirements of the municipality.