Method for supplying combustion gas in incineration systems
AssigneesMartin GmbH fur Umwelt- und Energietechnik, Covanta Energy Corporation
InventorsJohannes Martin, Joachim Horn, Oliver Gohlke
Life of this patent
Estimating the term…
Abstract
The combustion system for implementing the process has a combustion grate, hoppers below the combustion grate for supplying primary combustion gas through the grate and nozzles that lead into the furnace above the combustion grate to supply secondary combustion gas. At least one extraction duct for flue gas is provided at the rear end of the furnace above the combustion grate. This duct is connected to the suction side of a fan. The pressure side is connected to nozzles arranged in the upper area of the flue gas pass. The nozzle height allows the flue gases a residence time of at least 1 second after secondary gas is supplied.
Claims10
Method for combustion control in incineration systems, in which a fuel is conveyed to an incineration grate, primary combustion gas is passed through the fuel, and secondary combustion gas comprising ambient air without any additional fuel is introduced through nozzles directly into a waste gas stream, above the fuel, and in which part of the waste gas stream is drawn out of the waste gas stream in a rear incineration region and passed back into the combustion process as internal recirculation gas, wherein a sum of primary combustion gas amount and secondary combustion gas amount is lowered to such an extent that essentially stoichiometric reaction conditions are achieved, with reference to the waste gas stream directly above a secondary combustion gas plane and below a tertiary combustion region, without introducing any additional fuel and that said internal recirculation gas is prevented from entering a primary combustion region and a secondary combustion region and is passed into the tertiary combustion region, in which the waste gases have a dwell time of at least one second after introduction of the secondary combustion gas.
Dependencies are inferred from the claim text.