| Abstract [eng] |
The prevailing technologies for boiler flue gas desulphurisation and denitrification are selective. The combined impact on the reduction of overall emissions of biofuel reciprocating grate boilers has not been sufficiently studied. This dissertation is intended to determine the combined effects of primary and secondary measures on nitrogen and sulfur emissions. Experimental studies were carried out in industrial boilers (4 - 12 MW) and research stands (20 kW) of similar design and operating conditions, burning wood and waste of agricultural, industrial and animal origin. Selective non-catalytic reagents (NH3, (NH2)2CO), solid reagent (CaO), flue gas recirculation, excess air and combination of these measures on flue gas NO2, N2O, NH3, HCN, SO2, SO3 and H2S emissions were determined. Flue gas recirculation and insufficient excess air have been found to reduce NO, NO2, NH3, SO3 and H2S emissions but increase SO2, HCN and N2O emissions. These methods must therefore be combined with additional desulphurisation measures. Experimental measurements also showed that selective non-catalytic reagent ((NH2)2CO) reduces not only NO, NO2, but also SO2 and H2S concentrations in biofuel combustion products. The dissertation presents a methodology for the calculation of NOx and SO2 concentrations in flue gas based on the results of experimental research, which allows for the optimal selection of emission reduction measures. |
