A quick glance through the engineering interventions at a mining and metals major - center of excellence

1. By
Sandeep Gupta
sandeepgp1970@gmail.com

2. Role for Safety @HZL
1. Apex committee member secretary for safety excellence with globally
renowned consultant DuPont at HZL.
2. Process Safety Management (PSM) Incubation Center. Pro active approach.
Engineering support for process safety Incidents.
3. Structural and Mechanical Integrity management (part of PSM) coordinator
HZL wide.

3. Safety Excellence :
Key Guidelines, Intuitions and motivations
 Safety First. Safety is commitment for self , your coworkers and neighborhood. It is un
compromisable.
 Safety comes by your awareness and behavior.
 Devil’s advocacy to identify the hazards, think beyond what is evident. Look beyond
compliances for mega hazards to start with. For Safety Engineering interventions
prevent failures and go beyond compliance of statutory requirements also beyond
CAPA and HAZOP, use FMEA based on learning's from incidents elsewhere on the
subject equipment/schenario.
 Be proactive in learning from others , it may be very costly if you learn from your own
experience.
 Zero harm target can’t be achieved by sermons, It has to be by design. For towering
targets the efforts have to be deep. That of 10X engineer and 10x leader.
 Use engineering and technology (advanced NDT and Inspections tools etc) to the maximum.
 Consultants have mandate limit of involvement on engineering side, as a client , you don’t.
 Always integrate the learning into the system.

4. Illustration case study ( for atypical insight and
consistent efforts on mega hazard)
Sulphuric acid plant and its storage tanks are mega hazards at Zinc and Lead
smelters.
Two out of four 5000 MT storage capacity tanks of Sulphuric acid at Pyro
Plant, Chanderia were giving frequent leakages problems. (ST 1 and 2).
Usual and regular plate thickness measurement and tilt measurement of
the tanks were carried out. Ground had up heaved due to acid seepage
underground. Unit Engineering head on the basis of steel tank sheet
thickness basis prioritized to replace the tank#1 first. Product line with
96% min purity was unusually getting punctured frequently. Based on
learning from a Process safety Incident catastrophe elsewhere, I did
visualization by combining thickness report and tilt report , failure mode
analysis and devil’s advocacy of the degradation of acid tanks. By this
analysis ST2 tank was more dangerous than ST1 .In ST 1 thickness
reduction was in small patches all around(they were scattered) . In ST#2
the thickness reduction was in a almost vertical line and at the same time
the tilt was such that the vertical line with less thickness was lowest . This
was a dangerous recipe of potential vertical rupture of tank, tank could
then spin, travel a distance and finally collapse.

5. Illustration case study( for atypical insight and consistent
efforts on a mega hazard)
For replacement of tank a raised ring pyre type foundation suggested in
place of monolithic low raise foundation for easy detection of leakage
point of tank bottom. API 650 inspection practice was started with M/s
SGS. For the product acid pipe failure, speed of the acid in pipe was
detected two times the recommendation according to the MOC- MS pipe
<0.5 m/s . This recommendation was not known to the team. Upheaval
could over stress the overhead piping and resultant pipe failure could be
highly dangerous- Pipings were distressed and a glass indicator for the
stress placed on the pipings- poka Yoke. AET based inspection of tanks
bottoms recommended for future.

6. Safety Contributions and Achievements
My zone 2 topped among 6 zones in safety management system
assessment on continuous basis.
Initiated a sub committee on Training , Information and communications out
side the frame work and later agreed by consultant.
‘Adaptation’ of the excellence model or frameworks to application –example PSM
‘originated for oil and gas industry and toxic chemicals, tweaked for the mining.
For acceptability and max gains.
Engineering controls : writing safety plans to prevent failures and go beyond
‘compliance of statutory requirements (i)Carbon monoxide safety at furnaces,(ii)
liquid metal handling, melting and casting operations, including use of
microwave for drying of cathode sheets, MMI for liquid metal kettle failure
prevention, metal dissolution prevention(eg Ni should be reduced with Cu and
lead ) sourced standard of Anglo American for hot materials (iii) Material
handing and conveying safety and guarding standards.(iv) Sulphuric acid
transportation by road tankers. (v) Toppling of tipper trucks safety. HCV parking
safety etc.

7. Safety Contributions and Achievements
FSIPP- fatality safety incident prevention plan roll out and usage of Bow tie
analysis. Several fatality and process incident potential awareness and prevention
by proactive approach of learning from database and case studies of incidents else
where.
Atypical fatality potential incidents search and case study discussion through
safety contact Ex (i) Pressure explosion in column of Zinc refining Plant at
Pyro.(ii) Zn powder is non explosive but an unexplained incident of fatality in
African plant(iii) Zn fumes fever fatality(iv) Interaction in special condition of
high temperature to explode – CO and H2O2; (v)Pirhana Solution creation
possibility due to drainage of H2O2 in sulphuric acid plant area. (vi) Gyratory
crusher pit liner plates shooting off during zincing.

8. Safety Contributions and Achievements
Safety Incident investigations into five cases.(each of these had in depth technical expert
analysis akin forensic analysis and recommendations beyond the incident and covered
Holistic Safety plan for the subject equipment)
 Viz Pneumatic powder tanker blow off(there was recommendation of regular pressure
test , my RCA was a faulty change where a compressed air point was added above the
fluidization pad of the tanker)
 FRP tank of Hypo chloride bottom failure, implosion of FRP duct at roaster 1 acid plant
(Till these two FRP incidents FRP maintenance was neglected, team thought that FRP
had no maintenance to be done except wooden hammer test. I introduced integrated
life cycle quality management Plan).
 Failure of crane hoist during lifting of Ausmelt furnace top for shutdown without load
application (I found the gear coupling didn’t have crowning in the gears) .
 Failure of man hoist in construction of Mansa Power Plant chimney construction.
(Suggested a retractable spider arms platform with coffin hooks and a positively locked
anchor beams for it at the chimney top and complete FMEA of the chimney construction
was done, including leanings from Hindalco, Balco and world over- going beyond
expectation of particular incident report only)
 Hydrogen safety at Purification plants and acid plant(candle filter damage by hydrogen
fire).

9. Safety Contributions and Achievements
Structural and Mechanical Integrity management (part of PSM)
coordinator HZL wide.
Proactive approach. Awareness module for structural integrity,
Failure mode analysis and Failure case studies in Vedanta group and
public domain. Plausible failure modes and control plan (beyond
compliance). Structures and equipment rehabilitation and detritions
prevention, assets sweating & health audits. Corrosion control plans for mining
equipment and acid plants.
(1) Distressed thickeners at pyro and abandoned fine slurry tank (concrete) at
mines rehabilitated, saving Rs 15 cr (2) Mechanical Integrity study & Plan of Six
Sulphuric acid plants, acid storage tanks, acid transport tankers & mining
equipment to contain detritions by corrosion control plan etc.(3) A subsoil
drainage system at Mahan smelter to safeguard against shallow water table and
consequent current, earth leakage (4) Ore pass, Mine adit tunnel integrity
(proposed armidilo plated reinforcement) (5) High vibrations problem in
Chinese ball mill foundation at Agucha mills.

10. Safety Contributions and Achievements
Structural and Mechanical Integrity management (part
of PSM) coordinator HZL wide.
 (6) Integrity program institutionalized for Reactors, bulk liquid tanks at
smelters.(7)Wooden log health inspection tools introduced(cooling tower
and reactors). (8) Metal Furnace cooling system and tap hole block
Integrity improvements. (9) Plant health audit and structural stability
program for Debari Zinc smelter.(12) In house Feasibility study for
conversion of traditional tailings slurry disposal into thickened paste to
save land requirement & reduce failure risk for pond(10) QAP/FQAP and
maintenance plan developed for FRP tanks, ducts. (13) Practice of
mothballing (preservation techniques) and achieved a vertical restart up
after six months of shutdown. Mothballing manual sourced. (14) AET and
other advanced condition monitoring tools scouted for furnace, roasters,
big tanks, reactors and large diameter shaft of rotary equipment - MI tools
trials.(by Hatch).

11. Thanks and a question – How does when measure safety
wisdom, contribution and commitment?