Abstract
The effect of combustion temperature on the emission of trace elementswas studied under O2/CO2 atmosphere during coal combustion in a laboratory scale fluidized bed combustor. The elemental composition of fine fly ash particles collected with a low pressure impactor(LPI)was quantified by X-Ray F1uorescence Spectrometer (XRF). The elemental composition of coal and bottom ash was quantified byinductively coupled plasma-atomic emission spectroscopy (ICP-AES). The results indicate that the contents of Mn, Zn, Cd and Cr in the fly ash increase with the rise of combustion temperature. It is found that the enrichment of Zn and Cd is greater in the submicrometer particles than the supermicrometer particles, but Mn and Cr do not enrich in the submicrometer particles. Mn, Zn, Cd and Cr display one peak around 0.1 μm. The relative enrichment factor (Rij) of four elements is in the order of Zn, Cd, Mn and Cr. Zn and Cd are mostly retained in fly ashwhileMn and Cr are retained in both the fly ash and bottom ash.
Highlights
In additional tothe major elements Si, Al, Ca and Fe, many coals contain trace elements such as Pb, Ni, Mn, Zn, Cd, Cr, and Hg that aretoxic trace elements [1-3]
The effect of combustion temperature on the emission of trace elementswas studied under O2/CO2 atmosphere during coal combustion in a laboratory scale fluidized bed combustor
The results indicate that the contents of Mn, Zn, Cd and Cr in the fly ash increase with the rise of combustion temperature
Summary
In additional tothe major elements Si, Al, Ca and Fe, many coals contain trace elements such as Pb, Ni, Mn, Zn, Cd, Cr, and Hg that aretoxic trace elements [1-3]. When the coal is burned in the furnace, the trace metals are released from the fuel and transformedinto ash. This can result in high concentrations of trace metalsin certain ash fractions. Due to the high heavymetal concentrations, the ash cannot be circulated back tothe soil, i.e. disposed of in conventional landfills or used as cement replacement and other reuse applications unless the heavy metals can be separated into a smallash sidestream.these elements can be emitted into atmosphere during coal combustion, posing a serious threat to human health and the environment. O2/CO2 combustion, using oxygen and recycled flue gas as a combustion medium, can achieve a CO2 concentration of more than 95% in dry flue gas to enable an easy CO2 recovery It can offer additional benefits of substantially reducing NOx, and SO2 emissions. The emission characteristics of trace elements in O2/CO2 atmosphere were experimentally investigated in a laboratory scale fluidized bed
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: IOP Conference Series: Earth and Environmental Science
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
