In this study, a high-S lignite coal was burned with hazelnut shells in a laboratory scale circulating fluidized bed (CFBC) with secondary air injection. The thermal capacity of the laboratory scale CFBC was 30 kW.  The system consists of a stainless steel insulated combustor which is 6000 mm in height and 108 mm in inner diameter, two cyclones, a return leg, an angled L valve, a distributor plate, a wind box, an air pre-heater, an air blower, a bag filter, a fuel feeding system and a gas analyzer. The combustion temperature is kept in the range of 800–850°C. During the combustion experiments, emissions in the flue gas were continuously measured. In this study, cold and hot tests were performed. The objective of the study was to maximize combustion performance, minimize the emissions, and to see the effect of various amounts of secondary air injection on emissions. The results of this study have shown that the co-combustion of lignite coal with hazelnut shells in a CFBC can be performed with minimum emissions. The results showed that emissions can be reduced with the addition of secondary air. With the injection of secondary air into the combustor, CO emission trends were found to be different for SAR< 20% and SAR> 20%. CO presence in the emissions helped the NO reduction.