Reaction kinetics of limestone - SOx in a thermogravimetric analyzer and a fluidized bed combustor = 열중량 반응기와 유동층 연소로에서의 SOx - 석회석 탈황 반응 특성

Cited 0 time in webofscience Cited 0 time in scopus
  • Hit : 217
  • Download : 0
The effects of reaction temperature, $CO_2$ partial pressure, the properties of six different sorbents and sorbent size on the reactivities of calcination and sulfation of limestones have been determined in a thermogravimetric analyzer (TGA). The calcination reactivity of limestone under air atmosphere increases with increasing reaction temperature and its apparent activation energy is found to be 31,500kcal/kmol. The calcination rate decreases with an increase in $CO_2$ partial pressure in the ambient gas stream but increasee increases with increasing reaction temperature. The apparent thermal decomposition reaction order of limestone under $CO_2$ gas mixture atmosphere and the apparent sulfation reaction orders of precalcined limes-$SO_2$ are found to be close to unity. The apparent activation energies are found to be 17,000 kcal/kmol for sulfation of precalcined limes with $SO_2$ and 19,500kcal/kmol for direct sulfation. The initial sulfation reaction rate of precalcined limes increases with increasing temperature, whereas the sulfur capture capacity exhibits a maximum value at 900$^\circ$C. In the direct sulfation, the sulfation reactivity and sulfur capture capacity of limestone increase with increasing temperature and decreasing $CO_2$ partial pressure. From the XRD spectra, $CaCO_3$ in sulfated limestone under 10%-$CO_2$ gas stream at 850$^\circ$C decreases sharply with reaction time; CaO increases with time up to 20 min and thereafter decreases with time. Also, $CaSO_3$ slowly increases with increasing calcination and sulfation reaction time. The decomposition temperature of limestone has been correlated with $CO_2$ partial pressure as: $$T_{\mbox{doc}}=35\;\mbox{In}(P_g)+915$$. The effects of reaction temperature, $CO_2$ partial pressure, exposure time, and physical properties of three different sorbents on the pore structure of limestone in sulfation and calcination reactions have been determined. The surface area of CaO formed by rapid calcination in...
Advisors
Kim, Sang-Doneresearcher김상돈researcher
Description
한국과학기술원 : 화학공학과,
Publisher
한국과학기술원
Issue Date
1992
Identifier
59779/325007 / 000865005
Language
eng
Description

학위논문(박사) - 한국과학기술원 : 화학공학과, 1992.2, [ xv, 268 p. ]

URI
http://hdl.handle.net/10203/29123
Link
http://library.kaist.ac.kr/search/detail/view.do?bibCtrlNo=59779&flag=dissertation
Appears in Collection
CBE-Theses_Ph.D.(박사논문)
Files in This Item
There are no files associated with this item.

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0