This review summarises results of our pilot-scale experiments to find suitable inhibitors for preventing the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) during waste incineration and to specify the role of the main factors affecting the inhibition process, and is based on doctoral dissertation of Ruokojaärvi (2002). Results of previous experiments reported by other researchers are also presented and compared with ours. The detailed aims of our experiments were (1) to compare the effects of different inhibitors on PCDD/F formation during incineration in a pilot plant, (2) to investigate the role of the particle size distribution of the flue gas on the inhibition of PCDD/Fs, and (3) to find the main parameters affecting PCDD/F inhibition in waste incineration. Prevention of the formation of PCDD/Fs with chemical inhibitors and the effects of different supply points, feed temperatures and process parameters were studied in a pilot scale incinerator (50 kW) using light heating oil and refuse-derived fuel as test fuels. Various concentrations of the gaseous inhibitors (sulfur dioxide, ammonia, dimethylamine and methyl mercaptan) were sprayed into the flue gases after the furnace, in addition to which urea was dissolved in water and injected in at different concentrations. The residence time of the flue gas between the furnace and the PCDD/F sampling point was varied in the tests. In another set of urea tests, urea-water solutions at three concentrations were mixed with the RDF prior to incineration. PCDD/F and chlorophenol concentrations, together with other flue gas parameters (e.g. temperature, O2, CO, CO2 and NO), were analysed in the cooling flue gases. The gaseous and liquid inhibitors both notably reduced PCDD/F concentrations in the flue gas, the reductions achieved with the gaseous inhibitors varying from 50 to 78%, with dimethyl amine the most effective, while that produced with urea was up to 90%. The PCDD/F reductions were greater at increased inhibitor concentrations and with increased residence time of the flue gas between the furnace and the sampling point. PCDD/F concentrations in the particle phase decreased much more markedly than those in the gas phase. The urea inhibitor did not alter the particle size distribution of the PCDD/Fs when the amount of inhibitor was adequate. Chemical inhibitors seem to offer a very promising technique for preventing the formation of PCDD/Fs in waste incineration. The addition of urea to the fuel before combustion proved to be very effective approach and could be a useful technique even in the full-scale incinerators.
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http://dx.doi.org/10.1016/j.scitotenv.2003.11.006 | DOI Listing |
Molecules
January 2025
Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Zhejiang Normal University, Jinhua 321004, China.
CO capture from the flue gas is a promising approach to mitigate global warming. However, regulating the carbon-based adsorbent in terms of textural and surface modification is still a challenge. To overcome this issue, the present study depicts the development of cost-effective and high-performance CO adsorbents derived from petroleum coke, an industrial by-product, using a two-step process involving thiourea modification and KOH activation.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Cangzhou Municipal Engineering Company Limited, Cangzhou 061000, China.
To improve the mechanical and durability properties of low liquid limit soil, an eco-friendly, all-solid, waste-based stabilizer (GSCFC) was proposed using five different industrial solid wastes: ground granulated blast-furnace slag (GGBS), steel slag (SS), coal fly ash (CFA), flue-gas desulfurization (FGD) gypsum, and carbide slag (CS). The mechanical and durability performance of GSCFC-stabilized soil were evaluated using unconfined compressive strength (UCS), California bearing ratio (CBR), and freeze-thaw and wet-dry cycles. The Rietveld method was employed to analyze the mineral phases in the GSCFC-stabilized soil.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Key Laboratory for Advanced Coal and Coking Technology of Liaoning Province, University of Science and Technology Liaoning, Anshan 114051, China.
In this study, the mechanisms of SO adsorption on lignite char and char-supported Fe-Zn-Cu sorbent (FZC sorbent) were investigated. The FZC sorbent was prepared by the impregnation of metal components on raw coal followed by steam gasification. Flue gas desulfurization experiments were carried out on a fixed-bed reactor at 100-300 °C by using simulated flue gas containing SO/O/HO balanced by N.
View Article and Find Full Text PDFChemosphere
January 2025
Department of Chemical Engineering, Birla Institute of Technology and Science (BITS), Pilani, 333031, Rajasthan, India. Electronic address:
Elevated emissions of flue gases deteriorate the quality of air, impacting both terrestrial and aquatic ecosystems through their contribution to acid rain and eutrophication. This study examines the bio-mitigation process in a packed bed reactor and its capacity to concurrently decrease the environmental consequences of industrial flue gases (CO, NO, and SO) and wastewater by employing mixed bacterial consortia. The highest biomass productivity achieved during the growth phase was 0.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Department of Energy Systems Engineering, Faculty of Engineering and Architecture, Burdur Mehmet Akif Ersoy University, 15030, Burdur, Turkey.
In this study, the effect of additives on particulate matter (PM) and flue gas emissions during the co-combustion of poultry waste and pine woodchips in air and oxy-fuel combustion conditions was examined. The appropriate additive for the fuel mixture to reduce PM emissions has been selected by a fast screening method based on thermogravimetric analysis (TGA) in oxygen environment. Among the additives CaHPO, MgCO, MnCO, MgPO, kaolin, CaO, and Zn, the most suitable ones were determined as Zn and MgCO.
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