The most significant feature of this desgin and the diffrence from the other known designs is to possess a secondary firing, which burns the fule gases where these have unburned gas and other materials, being the main source for air pollution. By this wy it minimizes the pollution, with increasing the effiency to avarage %80 givin an extra %30 energy saving . However to get acceptable results the suction in the chimney should be adequate and the coal should not have excess dust and moisture.

ISSY-L type lignite boilers are steel welded construciton. They are semi-cylindirical design and smoke type broilers. They are insulated with glass wool and covered with prismatic galvanised steel. Every side of boiler is accesible, providing us easy maintanence. They are manufactured according to TSE (Turkish standart) or DIN (German standar) and for 3 to 5 bars. It is recomended that a 35 or 50 cm height ash storage from brichet wall is prepared. A ash storeage inlet door is given with boiler.