TITLE:
Incineration of Municipal Sewage Sludge in a Fluidized Bed Reactor
AUTHORS:
Beata Kowarska, Jerzy Baron, Stanisław Kandefer, Witold Zukowski
KEYWORDS:
Biomass Power; Reburning; Nitrogen Oxides; NOx Reduction; Sewage Sludge; Fluidized Bed Combustion
JOURNAL NAME:
Engineering,
Vol.5 No.1A,
January
29,
2013
ABSTRACT: In the present study reduction of nitrogen oxides using reburning technology, during combustion of sewage sludge (fuel I) and the mixture of sewage sludge, wasted bleaching earth and CaO (fuel II), was carried out. The experimental works were conducted in a laboratory-scale fluidized bed reactor (power up to 10 kW) with application of two types of beds: chemically inert bed (sand) and chemically active bed (CaO). The second combustion (reburning) zone in the reactor was formed by dosing into an area above the bed, additional gaseous fuel (propane). Obtained reduction in emissions of nitrogen oxides in both types of beds was at a level 70% - 79%. Additionally bed of CaO has the desulfurizing effect and also reduces the CO concentration in the exhaust fumes. A significant drawback of active bed is the adverse effect on increase of the primary NO which enters the second combustion zone. The result of this fact is higher NOx emission during combustion of the same fuel in bed of CaO in comparison to the combustion of this fuel in the sand bed, when the same maximum degree of reduction of NOx will be obtained for both types of beds.