Page 31 - Steel Tech India eMagazine Volume October 2021
P. 31
92/ Ć 12 Ć 2FWREHU
7KHVH VDPSOHV ZHUH IXUWKHU UXEEHG ZLWK HPHU\ SDSHU Nitrogen Pickup at Basic Oxygen Furnace (BOF)
MXVW EHIRUH WHVWLQJ LQ /(&2 DQDO\VHU DV VKRZQ LQ )LJXUH 4.2 Effect of Hot Metal and Scrap Ratio on Nitrogen
7KH SULQFLSOH RI RSHUDWLRQ IRU QLWURJHQ PHDVXUHPHQW Content in BOF
LV EDVHG RQ WKHUPDO FRQGXFWLYLW\ 7& RI 6DPSOH JDVHV
SDVV WKURXJK KHDWHG UDUH HDUWK FRSSHU R[LGH ZKLFK 6WHHO VFUDS LV VXSSRVHG WR EH D JRRG VRXUFH RI
FRQYHUWV &2 WR &2 DQG K\GURJHQ WR ZDWHU &2 DQG QLWURJHQ 7KXV LQFUHDVLQJ SURSRUWLRQ RI VFUDS LQ WKH
ZDWHU DUH WKHQ UHPRYHG ZLWK D /HFRVRUE $QK\GURQH FKDUJH PD\ UHVXOW LQ WKH ULVH RI WXUQGRZQ QLWURJHQ LQ
WUDS WR SUHYHQW GHWHFWLRQ E\ WKH 7& FHOO *DV IORZ WKHQ WKH VWHHO PHOW 0RUH VFUDS PHDQV OHVV KRW PHWDO DQG
SDVVHV WKURXJK WKH 7& FHOO IRU QLWURJHQ GHWHFWLRQ
WKXV OHVV &ă2 UHDFWLRQ UHVXOWLQJ LQ OHVV UHPRYDO RI
4 Results and Discussions QLWURJHQ E\ &2 EXEEOHV 6R LQFUHDVLQJ VFUDS UDWLR DQG
4.1 Mapping of Nitrogen GHFUHDVLQJ KRW PHWDO UDWLR LQ %2) FKDUJH PD\ OHDG WR
LQFUHDVH LQ 1LWURJHQ FRQWHQW LQ WKH VWHHO ,W FDQ EH VHHQ
0DSSLQJ RI QLWURJHQ ZDV GRQH DW HDFK RI VWHHO PDNLQJ IURP )LJXUH WKDW QLWURJHQ OHYHO LV JUHDWO\ DIIHFWHG E\
YLD %2) /+) &DVWHU $W %2) QLWURJHQ ZDV PHDVXUHG
DIWHU ILUVW WXUQGRZQ GHQRWHG DV 7' %2) $W /+) QLWURJHQ
ZDV PHDVXUHG WZLFH 2QH VDPSOH ZDV WDNHQ MXVW EHIRUH
WKH WUHDWPHQW DQG DQRWKHU DIWHU WUHDWPHQW RI VWHHO ZKLFK
DUH GHQRWHG DV /+) ,1 DQG /+) 287 UHVSHFWLYHO\ $QG
DW ODVW QLWURJHQ ZDV PHDVXUHG DW FDVWHU ZKLFK LV VLPSO\
GHQRWHG DV &DVWHU 0DSSLQJ RI QLWURJHQ DW HDFK VWDJH
RI VWHHOPDNLQJ KDV EHHQ VKRZQ LQ )LJXUH
Fig. 4: Effect of Hot Metal and Scrap Ratio on Nitrogen
Content in BOF
WKH VFUDS TXDQWLW\ DVVXPLQJ VDPH TXDOLW\ RU JUDGH RI
VFUDS ,QFUHDVHG SHUFHQWDJH RI VFUDS LQ FKDUJH OHDGV
WR KLJKHU QLWURJHQ RQ WXUQGRZQ
Fig. 3: Nitrogen Mapping of Steel Melting Shop 4.3 Effect of Re-blows on Nitrogen Content in BOF
1LWURJHQ SLFNXS IURP WKH DWPRVSKHUH PD\ LQFUHDVH
1LWURJHQ YDOXH PHDVXUHG DW WXUQGRZQ KDV EHHQ
GXULQJ UH EORZV DV GXULQJ WKDW SHULRG %2) ILOOV XS
GHQRWHG DV %2) 1LWURJHQ DQDO\VLV RI VWHHO MXVW EHIRUH
ZLWK DLU ZKLFK LV WKHQ HQWUDLQHG LQWR WKH PHWDO ZKHQ
/+) WUHDWPHQW KDV EHHQ GHQRWHG DV /+) ,1 1LWURJHQ
WKH R[\JHQ EORZ UHVWDUWV 'XULQJ UH EORZ EDWK FDUERQ
DQDO\VLV RI VWHHO MXVW DIWHU /+) WUHDWPHQW KDV EHHQ
FRQWHQW LV ORZ DQG WKHUH LV QR YLJRURXV &ă2 UHDFWLRQ
GHQRWHG DV /+) 287 1LWURJHQ YDOXH PHDVXUHG DW
WR IOXVK RXW WKH QLWURJHQ +HQFH UH EORZLQJ FDXVHV
FDVWHU KDV EHHQ VLPSO\ GHQRWHG DV &DVWHU 0DSSLQJ
DQ LQFUHDVH LQ QLWURJHQ FRQWHQW $ KDUG EORZ FDXVHV
RI QLWURJHQ JDYH WKH UDQJH RI QLWURJHQ OHYHOV IRXQG DW
PRUH YLJRURXV &ă2 UHDFWLRQ DQG OHDGV WR ORZHULQJ RI
HDFK VWDJH RI VWHHOPDNLQJ 7KLV PDSSLQJ RI QLWURJHQ
QLWURJHQ 6R KLJKHU WKH GXUDWLRQ RI UHEORZ KLJKHU ZLOO
UHYHDOV WKDW QLWURJHQ FRQWHQW LV PLQLPXP DW %2) ZKLFK EH WKH SUREDELOLW\ RI QLWURJHQ SLFNXS )URP RXU FXUUHQW
IXUWKHU LQFUHDVHV VKDUSO\ IURP WDSSLQJ WR /+) DQG ODVWO\ DQDO\VLV RI VRPH KHDWV IRXQG WKDW DIWHU FHUWDLQ GXUDWLRQ
LQ WXQGLVK LW LQFUHDVHV VOLJKWO\ 6WXG\ RI IDFWRUV DIIHFWLQJ RI UHEORZ DSSUR[LPDWHO\ VHF LQ RXU FDVH QLWURJHQ DW
QLWURJHQ SLFNXS LV FDWHJRULVHG DFFRUGLQJ WR VWDJHV RI WXUQGRZQ LVa SSP YHU\ VLPLODU WR KHDWV ZLWK ]HUR
VWHHO PDNLQJ SURFHVV LQ VWHHO PHOWLQJ VKRS $ %DVLF UHEORZ +RZHYHU DW KLJKHU UH EORZ GXUDWLRQ DERYH
R[\JHQ IXUQDFH %2) % /DGOH +HDWLQJ )XUQDFH VHF WKHUH LV DQ LQFUHDVH LQ QLWURJHQ SLFNXS XS WR
/+) DQG & &RQWLQXRXV 6ODE &DVWHU 7XQGLVK && SSP
STEEL TECH