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Yingzhe Du Shengyong Lu Zheng Peng Xiaodong Li Jianhua Yan 《Journal of the Air & Waste Management Association (1995)》2013,63(2):230-236
Over the past decades in China, the number of medical waste incinerators (MWIs) has been rising rapidly, causing emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). In this study, samples of fly ash, ash deposits, and bottom ash from typical MWIs were analyzed for PCDD/Fs and their distribution characteristics. Results showed international toxic equivalent (I-TEQ) values in the range of 6.9–67 ng I-TEQ/g in fly ash and ash deposits, whereas the concentration in bottom ash was extremely low (only 1.33 pg I-TEQ/g), yet the generation of PCDD/Fs was mostly de novo synthesis in fly ash and ash deposits according to the ratio of PCDFs to PCDDs; the major distribution differences of PCDD/Fs in fly ash was manifested by the content of toxic furan 2,3,7,8-TCDF, but other toxic PCDD/Fs showed similar distribution. Other findings are that 2,3,4,7,8-PeCDF had the most contribution to TEQ concentration, and that the most abundant toxic furan congener is 1,2,3,4,6,7,8-HpCDF. Correlation analysis showed that there was no significant correlation between PCDD/Fs concentration and several other physical and chemical parameters.
Implications: This paper is of interest because it presents the emission performances of PCDD/Fs in ash from medical waste incineration in China. PCDD/F contents in fly ash and ash deposits vary between 6.9 and 67.3 ng I-TEQ/g. However, the concentration in bottom ash was extremely low (only 1.33?×?10?3 ng I-TEQ/g). The fingerprints of PCDD/Fs in fly ash are almost similar, except for 2,3,7,8-TCDF. There is no marked correlation between PCDD/Fs and other physicochemical properties. Supplemental Materials: Supplemental materials are available for this paper. Go to the publisher's online edition of the Journal of the Air & Waste Management Association. 相似文献
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煤矸石层燃与工艺研究 总被引:1,自引:0,他引:1
介绍了煤矸石层燃与工艺流程及其燃用特性,利用成型燃烧理论和助燃技术解决了煤矸石在层燃炉内难燃和烟尘污染严重等技术难题,为煤矸石废弃物的洁净利用提供了一种切实可行的新技术。 相似文献
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Sun Chen Chen Tong Huang Qunxing Wang Jun Lu Shengyong Yan Jianhua 《Environmental science and pollution research international》2019,26(9):8902-8913
Environmental Science and Pollution Research - Novel KMnO4-treated magnetic biochar (FMBC) was successfully synthesized by addition of Fe(NO3)3 during carbonization and KMnO4 treatment following... 相似文献
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Effect of temperature and oxygen on the formation of chlorobenzene as the
indicator of PCDD/Fs 总被引:1,自引:0,他引:1
Sampling and analysis of polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs) are both time-consuming and expensive. In principle,real-time monitoring of chlorobenzene(CBz) as an indicator for PCDD/Fs could be useful to control and optimize incinerator operating conditions.To test this strategy,CBz was analyzed together with PCDD/Fs in flue gas samples collected from a hospital waste incinerator.Moreover,lab experiments were conducted to investigate the eect of temperature and oxygen on CBz formation from fly ash from the same incinerator.The experimental results demonstrate that chlorobenzene(in particular PeCBz) correlate well with PCDD/Fs,in line with previous research.The optimum temperature of CBz formation is in a range of 350 to 400°C and CBz yield increases significantly with oxygen,in line with PCDD/Fs formation.This study is useful for confirming the de novo mechanism and defining correlations between CBz and PCDD/Fs. 相似文献
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The mechanochemical dechlorination of pentachlorophenol (PCP) was studied using CaO and SiO2 powder as additives. The e ects
of the milling time and additives on the dechlorination rate were investigated. The resulting product was characterized by X-ray
di raction (XRD), Fourier transform infrared spectra (FT-IR), thermogravimetric analysis (TG) and ion chromatography (IC). It is
found that grinding operation could dechlorinate PCP, with the formation of inorganic chloride and amorphous carbon. The addition
of quartz to the grinding mixture facilitated dechlorination. On the basis of the experimental results, the decomposition mechanism
was proposed. Decomposition predominantly proceeds through rupture of C–Cl bond in PCP molecule, followed by the formation of
inorganic chlorides. 相似文献
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PCDD/Fs in soil around a hospital waste incinerator: comparison after three years of operation 总被引:2,自引:1,他引:1
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) can be formed during the cooling of flue gases in waste incinerator. These pollutants are either in the gas phase or attached to the fine particles, escaping dust collection. After stack emission, they are slowly oxidized photochemically (gas phase), or eventually are deposited (dry and wet deposition of particulate) in earth surface. In 2007 and 2010, 11 soil samples were collected in the vicinity of a hospital waste incinerator (HWI), prior and after its startup. In order to find out any variation of PCDD/Fs in soil, in brief dioxins, their concentrations were analyzed by high-resolution gas chromatography with high-resolution mass spectrometry (HRGC/HRMS). Compared to the baseline survey (2007), PCDD/Fs in soil significantly increased, by average, +81.6% in total PCDD/Fs and +132.7% in international toxic equivalency (I-TEQ) unit. By principal component analysis (PCA), both the PCDD/Fs homologue and the HxCDF isomer profile in soil were found to become more similar with fly ash. Generally, this incinerator influences the soil only in a limited area. More comprehensive supervision, stricter management and more advanced technology should be implemented in this plant to reduce pollutants emission, even though the level of PCDD/Fs in soil is quite low at present. 相似文献