Pollutants generation characteristics from retired wind turbine blades treated with thermochemical methods

XIONG Xiaohe; ZHANG Yinan; LI Liangyu; ZHANG Jingjing; TAN Houzhang

doi:10.13225/j.cnki.jccs.2024.0231

Abstract：Due to the light weight,high strength,and long blades of wind turbine blades characteristics,it has been a diffi-cult problem for the recycling in the solid waste industry.The thermochemical treatment of retired wind turbine blades is a technology with great potential for large-scale industrial application.In response to the issue of pollutant emissions during the thermochemical treatment process,the pre-treated wind turbine blades thermal conversion experiments were conduc-ted on a tubular electric furnace experimental platform under four different temperatures of 400,600,800,and 1 000 ℃during N2,CO2,and air atmospheres,respectively.The pollutants emissions containing nitrogen and chlorine were tested.Under the CO2 and N2 ambience,HCN and NO are the main nitrogen-containing pollutants.As the temperature increases,HCN gradually increases.At 1 000 ℃,HCN-N is the most important nitrogen-containing component,accounting for 88.3％of total nitrogen.However,the proportion of HCl-Cl to total chlorine fluctuates little,maintaining around 5％.Un-der the air ambience,NO is the main nitrogen-containing pollutant,with a peak concentration of 918.3 × 10-6.Moreover,the oxygen in the NO mainly comes from the wind turbine blades themselves,rather than the external air.As the temperat-ure increases,HCl and HCN gradually decrease,reaching their maximum at 400 ℃,accounting for 46％and 8.4％of total chlorine and total nitrogen,respectively.CO2 has a significant promoting effect on the distribution of products,which is related to temperature and composition.CO2 can significantly promote the generation of HCN and NO at a high temperat-ure of 1 000 ℃,but the promotion effect is not significant at a low temperature of 400 ℃.At a low temperature of 400 ℃,CO2 has a significant promoting effect on the generation of NO2,while at a high temperature of 1 000 ℃,CO2 has no sig-nificant promoting effect on the generation of NO2.Considering that the oxygen generated by NO mainly comes from the blades themselves,traditional air classification is not effective in reducing nitrogen oxides.