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in Wiley Online Library (wileyonlinelibrary.com) Ferric sulfate is used as an additive in biomass combustion to convert the released potassium chloride to the less harmful potassium sulfate. The decomposition of ferric sulfate is studied in a fast heating rate thermogravimetric analyzer and a volumetric reaction model is proposed to describe the process. The yields of sulfur oxides from ferric sulfate decomposition under boiler conditions are investigated experimentally, revealing a distribution of approximately 40% SO 3 and 60% SO 2 . The ferric sulfate decomposition model is combined with a detailed kinetic model of gas-phase KCl sulfation and a model of K 2 SO 4 condensation to simulate the sulfation of KCl by ferric sulfate addition. The simulation results show good agreements with experiments conducted in a biomass grate-firing reactor. The results indicate that the SO 3 released from ferric sulfate decomposition is the main contributor to KCl sulfation and that the effectiveness of ferric sulfate addition is sensitive to the applied temperature conditions. V C 2013 American Institute of Chemical Engineers AIChE J, 59: [4314][4315][4316][4317][4318][4319][4320][4321][4322][4323][4324] 2013

The development of a high efficiency CFB power plant (once-through supercritical CFB technology) and the use of alternative fuels require advanced methods of control and knowledge of the dynamic behavior of the furnace. Dynamic response analysis is needed for design of control algorithms in load changes. The operation of a pilot CFB-reactor in dynamic conditions and in load changes is analyzed experimentally and by modeling at different process conditions. Reactivity parameters for different fuels can be extracted from simple dynamic measurements and then used in computations studying operation in load changes. Dynamic studies are also required to see the necessary requirements for the fuel quality and fuel feed system to maintain stable operation. For high volatile coals the fuel feeding must be steadier to keep the variation in the outlet oxygen concentration at some range than with coals with low reactivity or alternatively greater air coefficient is needed to prevent too low O2 concentrations, which can cause an increase in CO emissions. The fuel quality can be characterized by the fluctuation of oxygen concentration in flue gases in steady operation conditions, which depends on the fluctuations in the combustion and in the fuel feed and on operational conditions. The amplitude of the fluctuations was studied. For advanced controls, it is necessary to know the factors affecting the process dynamics, such as reactivity and the behavior of char inventory in bed. This information is also necessary in developing and optimizing the CFB boiler considering emissions, combustion process and furnace scale up.

The National Repository Library of Finland was founded in 1989 as a means of providing the most economical way of storing library material for all libraries in Finland. It also acts as a connecting link in the country's library network and a centre for interlending. The paper describes the cost savings that have been achieved (€3.5 million annually) by the use of this central facility. Interlibrary loan requests are processed within 24 hours of receipt. Physical copies are mailed to user libraries, and periodical articles are scanned and despatched electronically. Fulfilling an important function in national collection policy, the National Repository Library has allowed other libraries to concentrate on maintaining active local collections, in the knowledge that research material sent to the Repository Library can be made available to them quickly and efficiently. As repositories acquire more and more material they become print resources on a regional or national scale, leading to the possibility that in time they might come together in a network to create a Universal Repository Library.