2. ArcelorMittal South Africa (AMSA) is the largest steel producer in Africa.
AMSA produces 4.8 million tonnes per year of saleable steel.
The plant’s steel products are manufactured in an integrated process.
Raw materials such as iron ore, coke and dolomite are charged to blast
furnaces where they are converted to liquid iron.
The liquid iron is refined in basic oxygen furnaces and electric arc
furnaces to produce liquid steel.
The liquid steel is cast into slabs, which are hot rolled into heavy plate in
a plate mill, or into coils in a strip mill.
The coils are either sold as hot rolled sheets in coil or processed further
into cold rolled and coated products, such as hot dip galvanised, electro-
galvanised and pre-painted sheet, and tinplate.
Company Profile
3. • First encounter with the Industrial Energy Efficiency Project (IEEP) –
Dec 2013 with UNIDO experts becoming a valuable extension of the
AMSA energy efficiency team.
• Energy management systems (EnMS) expert level training – May
2014.
• Compressed air system optimisation (CASO) 2 day training – June
2014
• Pump system optimisation (PSO) 2 day training – Mar 2014
• PSO expert level training – Jul 2014
• Fan system optimisation (FSO) 2 day training – Sep 2014
• FSO expert level training – Oct 2014
• Steam system optimisation (SSO) 2 day training – Sep 2014
• SSO expert level training – Feb 2015
• In the process of implementing EnMS – ISO 50001, energy systems
optimisation (ESO) assessments and case studies in pumps, fans,
steam and compressed air.
Arcelor Mittal VDBP - NCPC / IEEP Journey
4. ArcelorMittal VDBP - EnMS implementation results:
Electricity and natural gas data on baseline period 2013
Actual Savings 2016 – Approx. R105 million!
ESO Assessment Results - Case Study
Compressed air leak detection assessment R3.6 million
Pump system optimisation assessment (Ph1) R25 million
Compressed air system optimisation assessment R36 million
Steam system optimisation assessment
(Incl. power generation)
R175 million
5. Status of Energy Phase1 Pump Savings Projects
with the assistance of UNIDO / NCPC Funding
Plate Mill
Descaler
pump Ph1
Plate Mill
Descaler
pump Ph1&2
BF- D Furnace
cooling pumps
5 Stand South
Ph I Cool
pump
5 Stand South
Ph 2 Cool
pump
HSM-HP Pump
(after VSD’s)
Savings study
mechanism funded by
NCPC
Run best out of
3 pumps only
after pump
efficiency test
Refurbish
pumps
Run 1 pump
only
Run 1 less pump
Reduce friction
Reduce orifice
size at bypass
Automate main
pumps on/off
Analyse /
optimise in
PumpMonitor
Savings
(Rand)
R253,246 R458,557 R1,498,421 R811,992 R900,113 R2,200,000
Energy savings
(kWh p.a)
358,705 649,514 1,971,607 1,014,990 1,125,141 2,820,513
Total equipment
investment VDB
(Rand)
None
(completed)
R457,053
(completed)
R 676,640
(completed)
R30,000 R300,000 R508,000
Payback time
N/A 12 months 5.5 Months <1 month 4 months 3 months
Project status & plant
support
Completed M&V Audit Completed
Implemen -
tation
Proposal Proposal
6. How the Blast Furnace (BF-D) Pump System Works
Motor Data :
Rated Power 315 kW
Voltage 3 300 V
Full Load Amps 68 A
Speed 998 RPM
Pump Data :
Salweir Centrifugal Split Casing Double
suction
Model SDA 400-500
Type 400/500
Impeller Diameter 478mm
Cooling Tower
Sum
p
Heat
Exchangers
BF-D
Close
System
IN
BF-D
Close
System
OUT
7. BF-D Pump System - Root Cause Analysis
Pump
Station
BF-D
New Water Level increase
NPSH
9. BF-D Pump System - Root Cause Analysis
Pump operation
outside BEP
2
Inlet cavitation
Low NPSH
available
Inline strainers got
blocked restricting
flow
Plastic cooling
tower packing
collapsed and
contaminated water
Strainers at cooling
tower and pump
suction were not
effective
2.1
Cooling tower fill is
in bad state due to
ageing. End of life.
2.2
Strainers cause
high ∆P even when
clean
Design restriction
2.3
Long rusted inlet
pipes with elbows
increase pipe
resistance
Pipes ageing
2.4
One out of two inlet
valves stuck in
close position
restricting half of
the flow
Butterfly valve
sleeve damaged
during installation
cause disk to
become stuck
Installation is too
rigid. Valve had to
be forced into
position
2.5
Low level in the
sump
Water overflows to
BF-C sump
Leaking sluices
2.6
No control by
operational
personnel
2.7
Lack of
maintenance &
lubrication
1
Grease does not
enter the bearings
but stays in the
bearing cap
Bearings were not
greased by supplier
Bearings were not
greased by
maintenance
personnel
10. • Recommendations (without large capital) :
• Sump level increase to 100%.
• Automatic level control for top-up.
• Redesign suction pipe in order to reduce pressure loss
o Use bigger size pipe;
o Regularly clean strainers; and
o Remove elbow on inlet.
• Regularly clean heat exchangers.
• Adjust flow based on temperature.
• Confirm ΔT requirements of the ‘BF closed loop’ system and
calculate the required flow rate of the ‘open’ loop system.
• Compare flow requirements with cooling degree days.
• Operate a single pump year round.
BF-D Pump System - Root Cause Analysis
Operation
outside BEP
2
Outlet cavitation
High back
pressure
Blocked heat
exchangers
increase system
pressure
Plastic cooling
tower packing
collapsed and
contaminated
water
Strainers at cooling
tower and pump
suction were not
effective
2.1
Cooling tower fill is
in bad state due to
ageing. End of life.
2.2Heat exchangers
were not cleaned
regularly
No maintenance
plan for heat
exchangers
cleaning
2.8
Not effective and
unreliable system
for monitoring HE
pressure drop
2.9
12. Effect of Increased Maintenance at the Right Time
on Total Operational and Energy Cost
13. The Plate Mill makes use of a
descaling pump system (1 out of 3
pumps in parallel) that sprays
concentrated high pressure water
onto the plate, after the heating and
rolling process, to remove any scale
that has formed on the plate.
Effect of Increased Maintenance on Total Operational and Energy Cost
14. Plate Mill Descaler PSO
- Worn Pump Reduce Head, Flow, Efficiency at Increase Power
