Abstract:
Despite increasing waste-to-energy (WtE) capacities, there remain deficiencies in comprehension of 136 kinds of tetra- through octa-chlorinated dibenzo-p-dioxin and dibenzofurans (136 PCDD/Fs) originating from incineration sources. Samples from twenty typical WtE plants, encompassing coal-fired power plants (CPP), grate incinerators (GI), fluidized bed incinerators (FBI), and rotary kilns (RK), yielded extensive PCDD/F datasets. Research was conducted on fingerprint mapping, formation pathways, emission profiles, and diagnostic analysis of PCDD/Fs in WtE plants. Fingerprints revealed a prevalence of TCDF, followed by PeCDF, while CPP and RK respectively generated more PCDD and HxCDD. De novo synthesis was the predominant formation pathway except one plant, where CP-route dominated. DD/DF chlorination also facilitated PCDD/F formation, showing general trends of FBI > GI > CPP > RK. The PCDD/F emission intensities emitted in air pollution control system inlet (APCSI) and outlet (APCSO) followed the statistical sequence of RK > FBI > GI > CPP, with the average I-TEQ concentrations in APCSO reaching 0.18, 0.08, 0.11, and 0.04 ng I-TEQ·Nm-3. Emission spectrum were accordingly formed. Four clusters were segmented for diagnosis analysis, where PCDD/Fs in GI and FBI were similar, grouped as a single cluster. PCDD/Fs in CPP and RK demonstrated distinctive features in TCDD, HxCDD, and HxCDF. The WtE plants exceeding the limit value tended to generate and retain fewer TCDD and TCDF yet had higher fractions of HxCDD and HxCDF. The failure of APCS coupled with the intrinsic source strength of PCDD/Fs directly led to exceedance, highlighting safe operational practices. This study motivated source tracing and precise evaluation of 136 PCDD/Fs based on the revealed fingerprint profiles for WtE processes.
摘要:
尽管废物转化能源(WtE)容量不断增加,对来自焚烧源的136种四-八氯化二苯并对二恶英和二苯并呋喃(136PCDD/Fs)的理解仍然不足。来自二十种典型的WTE植物的样本,包括燃煤发电厂(CPP),炉排焚烧炉(GI),流化床焚烧炉(FBI),和回转窑(RK),产生了广泛的PCDD/F数据集。对指纹图谱进行了研究,形成途径,发射剖面,以及WTE植物中PCDD/Fs的诊断分析。指纹显示TCDF患病率,其次是PeCDF,而CPP和RK分别产生更多的PCDD和HxCDD。从头合成是主要的形成途径,除了一种植物,CP路线占主导地位。DD/DF氯化还促进了PCDD/F的形成,显示FBI>GI>CPP>RK的总体趋势。空气污染控制系统入口(APCSI)和出口(APCSO)排放的PCDD/F排放强度遵循RK>FBI>GI>CPP的统计顺序。APCSO中I-TEQ的平均浓度分别达到0.18、0.08、0.11和0.04ngI-TEQ·Nm-3。相应地形成发射光谱。四组被分割用于诊断分析,GI和FBI中的PCDD/Fs相似,分组为单个集群。CPP和RK中的PCDD/Fs在TCDD中表现出独特的特征,HxCDD,和HxCDF。超过极限值的WtE植物倾向于产生并保留较少的TCDD和TCDF,但HxCDD和HxCDF的分数更高。APCS的失效与PCDD/Fs的内在源强度耦合直接导致超标,强调安全的操作实践。这项研究基于揭示的WtE工艺指纹图谱,推动了136个PCDD/Fs的来源追踪和精确评估。