The individual grate bar blocks
In accordance with the invention it is particularly advantageous that the individual grate bar blocks can be moved by means of the grate bar carriers, and/or that the firing grate has an angle of inclination of 8 to 11°. The movability of the grate bar blocks does not reduce the operational safety of the firing grate designed in accordance with the invention. The inventive firing grate may be designed for instance as an inclined counterflow grate or as an inclined feed grate or as a horizontally arranged feed grate.
In a further aspect of the invention the grate slots have a width of 1 to 1.5 mm. This width of the grate slots ensures that the fuel disposed on the grate does not drop through the slots, and that enough combustion air gets into the fuel layer. In particular the chain grate slots provided between two grate bars do not change their width during the operation, as the connecting pieces fix the individual grate bars such that a grate slot-width of 1 to 1.5 mm is reliably maintained.
In accordance with the invention it is furthermore provided that the connections between the grate bars and the connecting pieces or the inlet and outlet pieces are sealed by a flush cut of the contact surfaces of the workpieces and by graphite seals. Due to the cooperation of the flush cut contact surfaces of the workpieces with the graphite seals and with the inventive screw connections of the individual workpieces an absolutely reliable sealing of the cooling system is achieved, so that the operational safety of the firing grate is also ensured over an extended operation.
In accordance with the invention the grate bars lie on the connecting, inlet and outlet pieces and screwed to the connecting, inlet and outlet pieces by means of vertically extending screws. The large contact area and the screw connection lead to a good fixation of all workpieces and a safe sealing of the cooling system.
In some cases it turned out to be expedient when a horizontal, air-cooled firing grate known per se is provided downstream of the inventive fire grate china . In this way, a high burn-out of the fuel is advantageously achieved, although the thermal load-bearing capacity of the air-cooled firing grate is only 0.5 to 0.8 MW/m 2 grate area. Alternatively, a second inventive, horizontal, water-cooled firing grate can be provided downstream of the inventive firing grate, so that a high fuel burn-out is achieved with a high load-bearing capacity of the grate.
The postcombustion can be improved in accordance with the invention in that at the upstream side of the second air-cooled or water-cooled firing grate nozzles are provided, through which pulsed combustion air is introduced into the combustion space, where the pulsed air may also be preheated.
In accordance with the invention the horizontal, air-cooled fire grate provided subsequent of the inventive firing grate has connecting and end pieces, which have no connecting passages, but are otherwise designed corresponding to the connecting, inlet and outlet pieces.
In a further aspect of the invention the grate slots have a width of 1 to 1.5 mm. This width of the grate slots ensures that the fuel disposed on the grate does not drop through the slots, and that enough combustion air gets into the fuel layer. In particular the chain grate slots provided between two grate bars do not change their width during the operation, as the connecting pieces fix the individual grate bars such that a grate slot-width of 1 to 1.5 mm is reliably maintained.
In accordance with the invention it is furthermore provided that the connections between the grate bars and the connecting pieces or the inlet and outlet pieces are sealed by a flush cut of the contact surfaces of the workpieces and by graphite seals. Due to the cooperation of the flush cut contact surfaces of the workpieces with the graphite seals and with the inventive screw connections of the individual workpieces an absolutely reliable sealing of the cooling system is achieved, so that the operational safety of the firing grate is also ensured over an extended operation.
In accordance with the invention the grate bars lie on the connecting, inlet and outlet pieces and screwed to the connecting, inlet and outlet pieces by means of vertically extending screws. The large contact area and the screw connection lead to a good fixation of all workpieces and a safe sealing of the cooling system.
In some cases it turned out to be expedient when a horizontal, air-cooled firing grate known per se is provided downstream of the inventive fire grate china . In this way, a high burn-out of the fuel is advantageously achieved, although the thermal load-bearing capacity of the air-cooled firing grate is only 0.5 to 0.8 MW/m 2 grate area. Alternatively, a second inventive, horizontal, water-cooled firing grate can be provided downstream of the inventive firing grate, so that a high fuel burn-out is achieved with a high load-bearing capacity of the grate.
The postcombustion can be improved in accordance with the invention in that at the upstream side of the second air-cooled or water-cooled firing grate nozzles are provided, through which pulsed combustion air is introduced into the combustion space, where the pulsed air may also be preheated.
In accordance with the invention the horizontal, air-cooled fire grate provided subsequent of the inventive firing grate has connecting and end pieces, which have no connecting passages, but are otherwise designed corresponding to the connecting, inlet and outlet pieces.
