The Influence of Co2 on Pollutants Emission During Pyrolysis of Retired Wind Turbine Blades

Abstract

Multiple hazardous components would be generated during pyrolysis process of retired wind turbine blades. In order to effectively mitigate pollutants emission, this article investigated pollutants emission of retired wind turbine blades and the influence of CO2 on it during pyrolysis. Real-time flue-gas analyzer and gas chromatography-mass spectrometry were used to determine product components. The results showed that the main gaseous pollutants were HCN and NH3, and approximately 20-25% of nitrogen gaseous pollutant was NOx. As temperature increased to 600 °C, conversion of nitrogen in retired wind blades to gaseous pollutants first decreased and then increased as CO2 concentration in atmosphere increasing, which was opposite from that at 500 °C. The main nitrogen species in tar was nitrogen heterocycles. At 600 °C, toxic benzofuran and PAH in tar increased significantly. CO2 in atmosphere inhibited the generation of nitrile, which was beneficial for reducing the proportion of HCN in nitrogen containing phase pollutants. CO2 particularly boosted the generation of PAHs at 600 °C. What’s more, CO2 effectively promoted the secondary cracking of char or condensed tar and enhanced syngas generation. It was considered that 500 °C - 30% CO2-70% N2 as the optimal condition.

Keywords: Wind turbine blades, Carbon dioxide, Nitrogenous pollutant, Fused polycyclic