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Show (J) ~ - 19 - The curve A has been calculated by using another computer program and by assuming insignificant spatial temperature differences inside the particle. The curve B is based on the numerical solution of the equation (17). DISTRI~U'IO~ O~ PV~Ol~SIS 1.0 r-------======-----------, I~~--------------. 1200 0,8 '"" 1: 0,6 ~ I())) d=O. 1 mm @ iclrl N ~ 0,4 § DIAMETER O.lmm 0,2 Yo=O. 2 Tg=Tw=1 lOOK °f~~--0~, ~~--0~, O-10--0~, O~15--0~,~~-~O,~ TIME (5) '"" Fig. 12. The comparison of pyrolysis models. iE~~~~~iM~E ~~5i~~~~¥~~~5 I~~-------------~ d=O.lmm Tg=Tw=1100K 128) Yo=O. 2 ~I(m 1.------ ill cr ~ 7fXJ a: cr ill ~ ~~----------ill f- 12 ~~----------~~----====~ ~.O 0,2 0.4 0,6 0,8 PLACE (Surface=1. Centre=O) Fig. 14. Temperature profiles inside a coal particles during the pyrolysis _stage of the combustion. 1.0 ~ 7fXJ Yo=O. 2 a: cr ~ ~ Tg=Tw= 11 OOK ill f- O,ali 0,010 0,015 T ItAC (s) o,tm Fig. 13. ~ratures at the surface and at the centre. ~E[t!]S~il1 [P~~IFO[l!ES O,tP.i I~r---------------. 4 8 12OO r===============~~~~==~~ 12 ("") I())) ~ Ol .:i. '-"750 f>-- ---- ...... ~!m ~ d=O. I mm ~ Yo=O.2 Tg=Tw=1 lOOK ems) ~.o 0,2 0,4 0,6 0,8 PLACE (Surface=I, Centre=O) 1,0 ~ ig. 15. Density profiles inside a coal particle during the pyrolysis stage of the combustion. The temperatures at the surface, at the centre, the density |