Micropollutant emissions (heavy metals - PCB - PAH - BTEX) from sinter plants and possible reduction strategies
This project aimed to characterise micro-pollutant emissions from sintering and to investigate process-integrated strategies to reduce these emissions. The ways to sample and analyse the micropollutants focussed on in this project have been clearly described and validated and can be used by the other European ironmakers. Solutions have been found to reduce the emissions of heavy metals: reduce their input by choosing the iron ores versus their heavy metal contents or by avoiding some reverts such as BF dust, increase the sinter basicity, if accepted by the Blast Furnace process, invest in a bag filter to collect the very fine dust because heavy metals are generally emitted under very fine particles ( <0.5 I. mu m), reduce the raw mix chlorine content because, for example, adding sea water to the mix, changes the lead partition to more being released in the waste gases and less being retained in the sinter. Solid fuels with high volatile compounds content are also not recommended, because they increase the PAHs, VOCs and methane emissions. PCBs have the same behaviour as PCDD/Fs and their contribution of WHO-12 PCBs is typically in the range 5% to 7%. So adding urea to the raw mix also seems effective in reducing PCBs emissions by a third. Activated coal injection in the waste gas stream allows an 80 % reduction of the PCB or PAH emissions and it seems also to have an interesting impact on the emissions of heavy metals. Using a metallic bag filter with zeolite injection can help to reduce the PAH emissions, but it has no PCB reduction efficiency. Injecting MEA into the gas mains does not help to reduce the PCB emission. No other good suppressant has been 1ound, except KDP, but its alkali content 1orbids ESP dust sinter recycling.
Bibliographic Reference: EUR 22443 EN (2007), 142 pp. Euro: 25
Availability: Katalogue Number: KI-NA-22443-EN-S The paper version can be ordered online and the PDF version downloaded at: http://bookshop.europa.eu
ISBN: ISBN: 978-92-79-04606-3
Record Number: 200719231 / Last updated on: 2007-07-05
Original language: en
Available languages: en