FLUENT FUEL FIRED BURNER

摘要

A fluent fuel fired burner formed with cylindrical discharge passages of annular cross section (8, 10, 12, 14, 16) arranged co-axially of a central passage (8) accommodating secondary burner means (6) and connected to discharge a combustion air flow. Outwardly successive passages of annular cross section are connected to discharge a pulverised fuel flow together with a combustion air flow, a secondary combustion air flow, a quaternary combustion air flow and a tertiary combustion air flow. The central passage (8) is connected and arranged to discharge less than 5 % of the total combustion air mass flow, and the outwardly successive passages (10, 12, 14, 16) of annular cross section are respectively connected and arranged to discharge 100 % of a pulverised fuel flow together with between 15 % and 25 % of the total combustion air mass flow, a secondary combustion air flow of between 15 % and 25 % of the total combustion air mass flow, a quaternary air flow of between 15 % and 30 % of the total combustion air mass flow and a tertiary air flow of between 30 % and 55 % of the total combustion air mass flow. This arrangement inhibits the discharge of oxides of nitrogen (NOx) in, whilst limiting the unburnt carbon content of, the combustion products.