Date post: | 20-Feb-2017 |
Category: |
Documents |
Upload: | marc-de-menibus |
View: | 16 times |
Download: | 1 times |
Formulated Lime (Flucal® Jet) co-injected or not with oxygen into Electric Arc Furnace fed with solid and liquid pig iron in Arcelormittal Cariacicaand Juiz de Fora (Brazil)
M. Ventura 1, M. Arcanjo* 1, T. Furtado2, B. Pinheira*2
M.A. de Menibus3, P. Bartolomeo3, P. Nicacio3,Perrin Eric4
1ArcelorMittal Cariacica2ArcelorMittal Juiz de Fora
3Belocal Lhoist do brazil, Sao José de lapa, 4Lhoist SA (belgium)
* speaker
Content
� Steel shop presentation
� System description
� Process parameter
� Experimental results
� Conclusion
2
3
AM JUIZ DE FORA�Capacity : 1.000.000 t�Products Type : Longs Manufacturing Process : BF/EAF
Plant Profile of AM Juiz de Fora�BFs (2 unid)• Capacity 360.000 t • Iron ore/Coal
�EAF(1 unit)•Tap Weight = 110t •Manufacturer – Paul Wurth
�LF (1 unit)•Capacity = 110t•Manufacturer – ASEA
�CCM•Manufacturer-Concast/Danieli
•5 strands •Radius 6m•Square Section 130 x 130
4
AM CARIACICA�Capacity : 600.000 t�Products Type : Longs Manufacturing Process : EAF
�EAF(1 unit)•Tap Weight = 75t •Manufacturer – Demag
�LF (1 unit)•Capacity = 75t
�CCM (1 unit)�100x100; �120x120; �130x130;�150x150 and�160x160mm
Plant Profile of AM Cariacica
5
Production flow
�Continuous Casting Machine
�Pig Iron �Scrap
�Scrap
�Shear
�Dedusting
�Ladle Furnace �Electric Arc Furnace
�Continuous Casting Machine
�Blast Furnace�Gusa Líquido
�Pig Iron �Scrap
�Scrap
�Shear
�Dedusting
�Ladle Furnace �Electric Arc Furnace
AM Juiz de Fora : 30% Hot metal
AM Cariacica : 30 % pig iron
� lime 100% bucket charged � lime 100% injected
6
Motivations :Cost reduction, Productivity, Improved safety, Proc ess improvement
AM Cariacica AM Juiz de Fora
Project presentation : lime 100 % from bucket charged to 100% injected through the EAF wall
Technology presentation
Cariacica layout Process Technology International (PTI) injector
� Two silos of 240 t each.� Pneumatic system for lime transport to reach
200 kg/min.� Jetbox® and a QuadJet® (PTI) with burner
and lime injection in the centre.
7
Juiz de Fora layout Lumar injector � Two silos of 200 t each.� Pneumatic system for lime transport in 120
kg/min from PTI.� Air-shrouded lime injector in the wall
Formulated lime (Flucal® Jet)� lime or dolime (0 to 10 mm)� Controlled granulometry
Injection pattern description
� AM Cariacica
8
� AM Juiz de Fora
�Injection flow pattern �Injection flow pattern
Dolime pattern
Lime pattern
Scrap
basketScrap
basket
Hot metal
First basket
Second basket
Scrap
basketScrap
basket
Hot metal
Experimental results (1/4)
9
89,9 90
88,9
90,7
88
89
90
91
Bucket Inject Bucket Inject
Metallic charge yield (%)
AM Cariacica AM Juiz de Fora
33,8 33 36,7 36,4
3032343638
Bucket Inject Bucket Inject
Power on time (min)
AM Cariacica AM Juiz de Fora
+2%
-2,5%-1%
407 403265 252
200250300350400450
Bucket Inject Bucket Inject
Electric cons. (kwh/t)
AM Cariacica AM Juiz de Fora
-5%
-1%
before Lime Bucked charge
after Lime injected
559 549 442 433
300
400
500
600
Bucket Inject Bucket Inject
Total energy (kwh/t)
AM Cariacica AM Juiz de Fora
-2%-1.8%
� Process improvement whatever the hot metal ratio
10
20
25
30
35
40
45
30000 35000 40000 45000 50000 55000
Hot Metal (kg/heat)
Power On (min)
Big Bag Flucal Linear (Big Bag) Linear (Flucal)
Experimental results : (2/4)Lime Injection Impact on Power On and on Electric consumption
150
250
350
30000 35000 40000 45000 50000 55000
Hot Metal (kg/heat)
Electric cons. Kwh/ton
Big Bag Flucal Linear (Big Bag) Linear (Flucal)
Experimental results (2/3)
11
3,67 3,294,1
2,7
234567
Bucket Inject Bucket Inject
Refractory wear (kg/t)
AM Cariacica AM Juiz de Fora
-34%
39,8 39,1
39,5 52
2030405060
Bucket Inject Bucket Inject
Total fluxe specific cons. (kg/t)
AM Cariacica AM Juiz de Fora
+33%-2%
before Lime Bucked charge
after Lime injected
27,5 25,528,8
24,8
202326293235
Bucket Inject Bucket Inject
Fetot in EAF slag (%)
AM Cariacica AM Juiz de Fora
-14%-7%
-10%1,3 1,24 0,84 0,78
0,50,70,91,11,31,5
Bucket Inject Bucket Inject
Electrode cons. (kg/t)
AM Cariacica AM Juiz de Fora
-7%-4,5%
Experimental results (3/3)
12
8797
8698
708090
100110
Bucket Inject Bucket Inject
CaO Yield (%)
AM Cariacica AM Juiz de Fora
0,530,67
0,45 0,72
0,20,40,60,8
Bucket Inject Bucket Inject
Phophorus removal (kg/t)
AM Cariacica AM Juiz de Fora
+14%+60%+24%
before Lime Bucked charge
after Lime injected
+11%
Other operational impacts
� Safety : elimination of contact with lime
� Manpower reduction
� Time reduction to prepare the scrap bucket
� Workshop cleanliness : reduction of lime dust
� Much lower stock of big bags. More free areas
� No more losses of big bas stock due to the rain
� Refractory ladle life time increase
13
ExplanationsImprovement on the control and management of slag formation
� Better foaming slag formation : � More efficient thermal barrier :� Improved heat transfer to the melt
� Faster slag formation� CaO and dolime dissolution increase� Phosphorus Removal raise� Higher refractory protection
� Better EAF process stability – smooth noise.
� Electrode profile and consumption.
� Easy tool and more flexible to adjust the slag during the process
14*Takao Nakagiri & al, NSSMC presentation to scanmet conference may 2012 in stoklhom
*
Conclusions
� Safety : remove many unsafely operations involving man and machine
� Process technology : easy tool for operators
� Implementation : real change in term of process control
� Results : significant impacts on :� Production cost, productivity, steel quality (P removal)
� Next step� Operation consistency and fluxes consumption optimization
15