By using fluidized-bed furnace and rotary-kiln+stoker furnace and four different kinds of industrial wastes such as waste wood, coffee mill, waste oils and waste plastics, we have drawn the following conclusions:
(1) A relationship between H6CBz and DXN is acquired, which is DXN=0.34×H6CBz1.1.
(2) The following means of emission reduction can be considered. (a) Reduction of DXN and Cl accumulation within the furnace, (b) control by the incinerated object, (c) control through the precursors of H6CBz, (d) improvement through operational control, (e) ammonia injection into the high-temperature zone of the furnace seems to be effective in reducing DXN and (f) DXN concentration is high with CO above 1800 ppm, though it decreases with CO below ≈10 ppm. 相似文献
Abstract The objective of the present study was to assess the potential interactive effects of two Great Lakes chemical contaminants, hexachlorobenzene (HCB) and mercury (HgCl2). Groups of 10 female Sprague‐Dawley rats were administered by gavage single doses of HCB (400, 600 mg/kg b.w. in corn oil), HgCl2 (10.0, 12.5 mg/kg b.w. aqueous) or combinations of both followed by observation for clinical signs of toxicity for 14 days. Five animals from treatment groups died before the termination of the study; one animal each in 600 mg HCB, 400 mg HCB + 10 mg HgCl2, and 600 mg HCB + 10 mg HgCl2, and two animals in 600 mg HCB + 12.5 mg HgCl2. The surviving animals were necropsied at the termination of the study, and hematological, clinical chemistry, histopathological and tissue residue analyses were performed. Relative liver weights were increased in both low and high dose groups of HCB but not in animals treated with HgCl2 alone. Co‐administration of HgCl2 did not alter the HCB effects on the liver weight of the animals. Serum cholesterol levels were increased in all the groups receiving HCB but not HgCl2. No interactive effects on other serum parameters were seen in animals administered with both chemicals. Mild to moderate morphological changes occurred in the liver, thyroid, thymus, ovary and bone marrow of rats exposed to HCB or HCB + HgCl2, and in the kidney of HgCl2 or HgCl2 + HCB treated animals. More severe histological changes occurred in the groups receiving both chemicals. The histological effects appeared to be additive. It was concluded that co‐administration with HCB and HgCl2 resulted in additive effects in some of the endpoints measured but no synergism or antagonism was observed. 相似文献
Mean hexachlorobenzene (HCB) and hexachlorocyclohexane (HCH) concentrations, measured in seawater and air samples, confirmed the decline in levels of these compounds in Antarctic air and water. However, low α/γ-HCH ratios in air at the beginning of the sampling period suggest a predominance of fresh lindane entering the Antarctic atmosphere during the Austral spring probably due to current use in the Southern Hemisphere. Water-air fugacity ratios demonstrate the potential for HCH gas deposition to coastal Antarctic seas, while the water-air fugacity ratios for HCB imply that volatilization does not account for the observed decrease of HCB in surface seawater. HCH concentrations found in krill samples were correlated with seawater concentrations indicative of bioconcentration of HCHs from seawater. 相似文献
This paper explores issues of governance and decision-making structures associated with the problem of hexachlorobenzene (HCB) waste at Botany in New South Wales. From a government perspective, the problem is ‘downstream’ of a well-known national controversy over whether Australia should have a high-temperature incinerator (HTI) to ‘dispose’ of such scheduled wastes. The 1992 decision not to proceed with HTI followed an extensive process of public consultation, which, against the expectations of industry and government, saw the emergence of Australia-wide community opposition. Alternative national management plans were formulated for the treatment of several types of organochlorine waste, with the scheme of these plans first approved in 1993 by the Australian and New Zealand Environment and Conservation Council (ANZECC). The HCB Management Plan is one of three such plans (the others being for PCBs and organochlorine pesticides). With this, ANZECC established the Scheduled Waste Management Group comprising government officials, and the National Advisory Body (NAB) made up of stakeholders. Officially the NAB had oversight of the HCB problem until 2002 when it was disbanded. As a result of the HTI experience, new community consultation protocols were introduced in association with the alternative management plans. For HCBs, which are confined almost entirely to Orica's Botany site in southeastern Sydney, this led to the establishment of the Community Participation and Review Committee (CPRC), a representative body with review and advisory functions. This paper draws conclusions from this history about government processes of decision making, the role of individual and institutional actors, the central importance of trust, and the democratisation of risk management. Using concepts delineated by McDonell [1991. Toxic waste management in Australia: why did policy reform fail? Environment 33(6), 11–13, 33–39; 1997. Scientific and everyday knowledge: trust and the politics of environmental initiatives. Social Studies of Science 27, 819–863.] we identify swings towards, then away from institutionalised trust. Across two decades, government and industry have placed faith in centrally controlled mechanisms for public participation, hoping to garner trust and legitimate privileged technological solutions. On the ‘backswings’, these processes have seen public trust dissipate in the face of government misunderstanding of the opportunities for effective bureaucratic interventions. 相似文献
In the environmental conflict that surrounds the sighting of hazardous waste facilities there is usually a volatile mix of disparities in power, expertise and information access as well as differing views on risk, which are all played out amidst commercial arrangements and environmental justice concerns. In recent times, the volatility of this mix has been further compounded by the growing climate of public concern and distrust surrounding scientific developments and technology. While there is no 'quick fix' to the complex conflict that this entails, community information systems (CISs) based on participatory models can help address the outstanding issues of capacity, information access, power inequities and environmental justice. CISs are an effective response to the five crucial elements of a toxic dispute, that is, the dialogue, capacity building, information access, evaluation of hazards and risk, and expertise. This paper will review the role of community accessible information systems in the dispute in Botany over the management and destruction of Orica Australia's stockpile of the persistent organic pollutant, hexachlorobenzene (HCB). It will focus on the role of CIS in responding to the challenges for expert information delivery, and in addressing the disparity of informational power within the toxic dispute. 相似文献
Under the Stockholm Convention on Persistent Organic Pollutants (POPs), China is required not only to reduce polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF) but also unintentionally produced polychlorinated biphenyls (PCB), hexachlorobenzene (HCB) and pentachlorobenzene (PeCBz). A baseline of the sources in China that generate these unintentional POPs is needed for both research and regulation purposes. In this paper, we have compiled production data of potential sources in China and assessed them in five-year intervals from 2000 to 2015. Most of these activities experienced changes from rapid growth to slow growth. Measured data for PCB, HCB and PeCBz in samples collected from potential sources in China were reviewed. Most information was associated to thermal processes with high potential of emission, including waste incineration and ferrous and non-ferrous metal production. In addition, high levels of PCB, HCB and PeCBz were found as impurities in a few chlorinated products or as by-products in solvent production, which suggested organochlorine industry might be important sources. Finally, based on the studies reviewed, recommendations for future actions in research and policy as well as a few regulatory issues in China are discussed.
The chlorination and condensation of acetylene at low temperatures is demonstrated using copper chlorides as chlorinated agents coated to model borosilicate surfaces. Experiments with and without both a chlorine source and borosilicate surfaces indicate the absence of gas-phase and gas-surface reactions. Chlorination and condensation occur only in the presence of the copper catalyst. C2 through C8 organic products were observed in the effluent; PCDD/F were only observed from extraction of the borosilicate surfaces. A global reaction model is proposed that is consistent with the observed product distributions. Similar experiments with dichloroacetylene indicate greater reactivity in the absence of the copper catalyst. Reaction is observed in the gas-phase and in the presence of borosilicate surfaces at low temperatures. The formation of hexachlorobenzene is only observed in the presence of a copper catalyst. PCDD/F were only observed from extraction of the borosilicate surfaces. A global reaction model is proposed for the formation of hexachlorobenzene from dichloroacetylene. 相似文献
Hexachlorobenzene (HCB) in the milligram range was co-heated with calcium oxide (CaO) powder in sealed glass ampoules at 340–400 °C. The heated samples were characterized and analyzed by Raman spectroscopy, elemental analysis, gas chromatography/mass spectrometry, ion chromatography, and thermal/optical carbon analysis. The degradation products of HCB were studied at different temperatures and heated times. The amorphous carbon was firstly quantitatively evaluated and was thought to be important fate of the C element of HCB. The yield of amorphous carbon in products increased with heating time, for samples treated for 8 h at 340, 380 °C and 400 °C, the value were 17.5%, 34.8% and 50.2%, respectively. After identification of the dechlorination products, the HCB degradation on CaO at 340–400 °C was supposed to through dechlorination/polymerization pathway, which is induced by electron transfer, generate chloride ions and form high-molecular weight intermediates with significant levels of both hydrogen and chlorine, and finally form amorphous carbon. Higher temperature was beneficial for the dechlorination/polymerization efficiency. The results are helpful for clarifying the reaction mechanism for thermal degradation of chlorinated aromatics in alkaline matrices. 相似文献