My experience at KTH, Sweden
Transcription
My experience at KTH, Sweden
Biofuels Research Infrastructure for Sharing Knowledge CASE STUDY My experience at KTH, Sweden Alen Horvat of the Carbolea Research Group at the University of Limerick, Ireland, outlines his visit to the Royal Institute of Technology (KTH) in Sweden Carbolea is a young and ambitious research group based at the University of Limerick, Ireland. Its main research area is lignocellulosic and waste biomass conversion via processes such as gasification, pyrolysis, hydrolysis, and catalytic upgrading of intermediate products. The gasification team consists of four-five researchers operating a large lab scale bubbling fluidised bed gasifier with a feeding rate of approximately 3kg. My own research focus is on the effects of process conditions on tar composition, particularly tar sampling, post sampling and final instrumental analysis. I felt that it would be useful for me to research alongside other gasification experts, and I also wanted hands on experience working with other gasifiers and particularly working using different tar sampling and analysis techniques. KTH is a leading gasification centre and seemed to offer the opportunity for both. My experimental plan was to investigate the effect of biomass pretreatment (torrefaction) on tar composition. The proposed study on gasification of non-torrefied and torrefied Miscanthus Gigantheus was approved for the duration of two weeks, and in September 2014 a team of three Carbolea researchers travelled to Stockholm. The team used a top fed fluidised bed reactor with a high temperature filter (also called an LDU) and a feeding rate of 3-4kgh-1 during the experimental campaign. The LDU enabled upscale continuation of our previous study of torrefied biomass – previous studies were conducted on a smaller test rig with a feeding rate of approx. 0.5kgh-1 and side screw feeding. Figure 1: Biomass preparation sieving. Figure 2: SPA sampling. The study visit included feedstock preparation (i.e. shredding, sieving), large lab scale gasifier operation (i.e. testing the feeding system, maintenance work between tests), and Solid Phase Adsorption (SPA) tar analysis. Since this was the first time torrefied biomass Figure 3: Adjusting the feeding hopper. Continued on next page 1 Biofuels Research Infrastructure for Sharing Knowledge CASE STUDY My experience at KTH, Sweden had been gasified at KTH we had to deal with issues such as adjusting the steady feeding rate, char accumulation in the bed, sintering etc. The gasifier operated under atmospheric conditions as opposed to well-developed pressurised tar sampling, which created new challenges. For that reason modifications of the tar sampling point were necessary during the first week of operation. Iraj Bavarian (one of KTH’s analytical chemists) kindly shared his experience in conducting SPA tar analysis and I showed him the methods we use within the Carbolea group. As a young gasification researcher it was exciting to be working at an organisation where gasification and tar analysis have a long history. Our full experimental plan could not be completed due to time consuming modifications and adjustments at the beginning of the visit. Three tests using torrefied biomass were conducted while non-torrefied biomass still needs to be tested in order to compare the two types of biomass. Therefore, another visit to the facility has been proposed, due to take place in 2015. BRISK Transnational Access remarkably accelerates knowledge transfer in the field of bioenergy, by making available research facilities across recognised organisations accessible to young researchers. This was Carbolea’s third participation in the BRISK project, and BRISK enhanced my individual research experience significantly. Figure 4: Extraction of SPA cartridges. The benefits I gained from the BRISK Transnational Access experience would not have been possible without the welcoming and helpful personnel at KTH: Christer Rosén, Mikael Lundgren, Klas Engvall and Iraj Bavarian. I would also like to acknowledge my colleagues from Carbolea; Marzena Kwapinska and Natalie Taupe who worked alongside me during the visit. Thank you and I look forward to my participation in 2015. Figure 5: Marzena Kwapinska and Natalie Taupe. Contact www.briskeu.com Andrew Martin Royal Institute of Technology (KTH) E: [email protected] W: www.kth.se 2