The tightening of new national and European regulations for air pollution control requires the use of new concepts and modern technologies to optimize the combustion process and thus reduce pollutant emissions in biomass boilers. This work outlines the development of the CIC-technology in automatically charged domestic biomass boilers for the use of low-quality wood chips and other fuels which are classified under the fuel number 8 and 13 of The First Ordinance of the Small Firing Appliances, § 3. The CIC-technology, a multi-stage combustion with an integrated flue gas treatment technology, consists of two units: the cyclone combustion chamber as a NOx reduction zone and the packing technology as a main thermal treatment step. The staged combustion enables the targeted supply of air in its three steps. Also, the enlargement of the active reaction zones in both the reduction and oxidation chambers ensures the optimization of the combustion conditions over the different operating phases. As a result, both the main combustible pollutant emissions (CO, OGC and particulate matters) and NOx emissions are significantly reduced.