In this system, the solid fuel received from the bunker is burned by feeding it under the grill to the furnace by means of a screw screw. It burns coal, pieces of wood, wood shavings and dust, sunflower husks, olive seeds, cotton waste (shank), hazelnut shells and similar solid fuels up to 50 mm in size.
The efficiency of steam boilers having this system is minimum 75%. Natural gas and liquid fuel can be burned in a short time. If desired, these boilers are manufactured to burn both solid and liquid / gas fuel. In these systems, which are widely used in the industry, processes such as dehulling and swelling of burning fuel should be performed. In this case, the cold air entering the furnace adversely affects the combustion regime.
In addition, in these systems, it is not possible to obtain satisfactory results in the combustion of coal with low melting temperature and coal dust. In consideration of these and similar disadvantages, it is useful to prefer Fixed Ladder Grid, Forward Propelled Ladder Grid or Pneumatic combustion systems in large capacity systems.