Study On Emission Factors And Identification Of Markers Of Polycyclic Aromatic Hydrocarbons For Stationary Sources

Polycyclic aromatic hydrocarbons(PAHs)are the first known chemical carcinogens.Although the presence in the environment is trace.However,it constantly generates,migrates,transforms and degrades,and enters the human body through the respiratory tract,skin and digestive tract,which greatly threatens human health.Biomass combustion,coal-fired power plants,and waste incineration power plants(including plastics)are inevitable sources of PAHs in our lives.It is necessary to identify the main sources of contribution and quantify their contribution rates.This study initially obtained the measured data of biomass polycyclic aromatic hydrocarbon emission factors in the Beijing-Tianjin-Hebei region.The ?18PAHs for all the bottom ashes varied significantly from 65.0±10.6 to 1310±129 ng/g.The various sized bottom ashes of sorghum had the highest PAH levels(from 1100±160 to1310±129 ng/g),while those from corn cob produced the lowest levels(65.0±10.6 to338±68.9 ng/g).NA,PHE,ACL,AN,FA,PY,FL,and AC dominated in all the bottom ash samples except for sesame.The bottom ashes from all bio-fuels were dominated by LMW-PAHs.Most ratios AN/(AN+PHE),BaA/(BaA+CHR),BaA/CHR,BbF/BkF,BaA/BgP,PY/BaP,and BaA/BaP varied significantly among the 8 bio-fuels,which indicated the strong influence of bio-fuel types on emitted PAHs and suggested that no series of coincident diagnostic ratios can represent all bio-fuels.BgP,BbF and IP are markers of PAHs for soybean,millet,sorghum,sesame and cotton,while AC and FL are corn,corn cobs and walnut branches are indicative of polycyclic aromatic hydrocarbons.Sorghum and sesame have a high potential toxicity risk.The PAH concentrations were in the range of 5.51–70.9ng/g for 16 coal-fired power plants(CFPPs)with individual block power capacity as 600 MW,significantly lower than886-916ng/g for 200/300 MW.The 18 CFPPs were dominated by low molecular weight ones.NA and PHE are markers of polycyclic aromatic hydrocarbons for CFPPs.PAH profiles for 16 CFPPs with 600 MW were significantly different from other industrial stacks based on higher coefficients of divergence.The BaP-based toxic equivalency(BaPeq)concentration and BaP-based equivalent carcinogenic power(BaPE)for 16 CFPPs with 600 MW were 0.834ng/g and 0.570,much lower than corresponding 20.5ng/g and 15.4 for 200/300 MW.The average value of waste incineration power plants and plastics is 2676.76 ng/g and 103.31 ng/g,respectively.The 3-and 2-ring PAHs were the predominant homologs.BaP,CHR,BkF,BgP,IP aremarkers of polycyclic aromatic hydrocarbons for waste incineration power plants power plant.PHE,BbF,BaP,IP are the main homologues of plastic burning bottom ash,and neither of the bottom ash can be used as a soil amendment.