This paper describes full lab-scale investigation of Middle-Bosnia coals
launched to support selection an appropriate combustion technology and to
support optimization of the boiler design. Tested mix of Middle-Bosnia brown
coals is projected coal for new co-generation power plant Kakanj Unit 8
(300-450 MWe), EP B&H electricity utility. The basic coal blend consisting of
the coals Kakanj: Breza: Zenica at approximate mass ratio of 70:20:10 is low
grade brown coal with very high percentage of ash - over 40%. Testing that
coal in circulated fluidized bed combustion technique, performed at
Ruhr-University Bohum and Doosan Lentjes GmbH, has shown its inconveniency
for fluidized bed combustion technology, primarily due to the agglomeration
problems. Tests of these coals in PFC (pulverized fuel combustion) technology
have been performed in referent laboratory at Faculty of Mechanical
Engineering of Sarajevo University, on a lab-scale PFC furnace, to provide
reliable data for further analysis. The PFC tests results are fitted well
with previously obtained results of the burning similar Bosnian coal blends
in the PFC dry bottom furnace technique. Combination of the coals shares, the
process temperature and the air combustion distribution for the lowest NOx
and SO2 emissions was found in this work, provided that combustion efficiency
and CO emissions are within very strict criteria, considering specific
settlement of lab-scale furnace. Sustainability assessment based on
calculation economic and environmental indicators, in combination with Low
Cost Planning method, is used for optimization the power plant design. The
results of the full lab-scale investigation will help in selection optimal
Boiler design, to achieve sustainable energy system with high-efficient and
clean combustion technology applied for given coals.