The task of the convector cooler is to cool flue gasses from the furnace, from 800 - 900 °C down to about 200 - 240 °C. This is done with convection to the surrounding air . The cooling capacity must therefore be able to remain low at moments when the incoming temperature is lower than normally.
After passing through the inlet convection pipe, the hot flue gas is lead through the upper collection duct. The flue gas is distributed through 12 parallell connected pipes where the flue gas is cooled through convection to the surrounding air. The cooled gas then enters the lower collection duct and on to the filter via the outlet channel. To avoid a too powerful cooling effect at start-up of the furnace and at low load, the cooler is partitioned in four sections.
The cooling effect is decreased by closing 1 to 3 sections. The cooling area can in this way be adapted from 13 to 52 m². The control system senses the temperature before the filter and adapts how much of the cooler that needs to be used. These are maneuvered by pneumatical shaft actuators. To acheive an even dust coating the sections are opened and closed in a cyclical pattern.
The cooler is placed on a support.