Led by a sustained focus on cost-effective production, the state-of-the-art world’s second largest silver mine Sindesar Khurd Mine (SKM), reported highest ever ore production, at 5.65 Mt, during FY 2023-24. Mined metal production (zinc and lead) also showed sustenance during the year. SKM achieved the highest ever mine development of 26.2 km, besides clocking ore treatment of 6.06 Mt, the highest in the mine’s history.
Equipped with cutting-edge technologies and best-in-class equipment, SKM has been on a consistent growth path since it became operational in 2006 with 0.3 Mtpa capacity. It currently has the distinction being one of the India’s largest underground mines, besides being one of the lowest-cost producers. SKM’s performance excellence is driven by its multiple standalone production centres, created by the main lens and a multitude of standalone auxiliary lenses in the mine’s deposit.
KEY OPERATIONAL MILESTONES OF FY 2023-24
In FY 2023-24, SKM reported a 1% increase in ore production over the previous fiscal, forging ahead on its strategic agenda to deliver responsible growth and value creation for the Company.
5.65 Mt
Ore Production
4.73%
Grade
242.2 kt
Mined Metal Production
26.2 km
Mine Development
SCALING NEW MILESTONES
FY 2023-24 saw SKM scale new milestones in operational efficiency as a result of several impactful initiatives and developments.
Strengthening of paste-fill reticulation, for increasing paste-fill flow from 166 m3/hour in FY 2022-23 to 177 m3/hour in FY 2023-24
Commissioning of ore production from lower D block (-235 mRL to -355 mRL) and from the E-Block situated at a depth of more than 900 metres from surface
Highest ever mine development of 26.2 km
AUTOMATING & DIGITALISING TO DRIVE EFFICIENCIES
To scale efficiencies, we adopted several new automation and digitalisation technologies during the year:
Automation of main pump station at -55 mRL in underground, enabling complete operations from the surface control room
Installation and commissioning of digital load scanner system underground at -165 mRL ore-pass, for real-time monitoring of the load carried and the fill factor
Commenced underhand mining below paste-fill at depth of more than 900 metres from surface, becoming the second mine in India, after Rampura Agucha underground mine, to achieve this feat
Installation of ‘timers’ on auxiliary ventilation fans underground, for power saving in idle hours and shift changeover time
CONTINUED EXPANSION AND UPGRADATION
Expansion and upgradation of the mine facilities continued during the year, augmenting the process efficiency at SKM:
Successfully commissioned a 617 metres long borehole of shotcrete, for smooth shotcrete transfer from surface to underground
Achieved 70% reduction in mine voids (from 1.0 mn m3 to 0.32 mn m3) by backfilling mine voids to improve global mine stability
During my training period, I rotated through departments like geotech, development, and control room digitalisation. I also gained authorisation to operate LMVs underground. In 2022, I received the Chairman’s Award in the digital category for pioneering India’s first Wi-Fi blasting project, earning the moniker ‘WI-FI Sandhya’. In 2023, I earned certification in Mine Rescue operations and joined India’s premier women’s rescue team, receiving accolades internally and nationally, including another Chairman’s Award for our collective achievements. These past three years have been transformative, marked by continuous personal growth. Immersed in Hindustan Zinc’s stringent safety and ESG standards, I’ve refined my skills and embraced leadership opportunities with unwavering determination.
Sandhya Singh Shift Foreman – Production Drilling, SKM
CASE STUDY
Boosting mine shaft utilisation through cage-skip
In a pioneering move, we installed a partition between cage (man winding) and skip (material winding), while operating both simultaneously, during the year. The initiative was aimed at enhancing the safety of our personnel. The previous lack of a partition between the two compartments within the 7.5-metre diameter shaft has now been addressed, significantly reducing the risk of material spillage from the skip compartment into the cage compartment. This was creating a bottleneck in simultaneous operation of skip and cage, which we have successfully removed with this first-of-its-kind initiative in the Indian mining industry.
Key features
Increase in operating hours from 12 to 16, post the installation of the partition
Assembled a screen between the buntons (steel cross bars installed at regular intervals to carry guides in the shaft), to ensure first-time right operations
Key outcome
Improved safety at the mine
Reduced need for rework, as a result of enhanced flexibility and agility
4 hours/day increase in hoisting system utilisation, with man winding being done simultaneously
Increase in hoisting capacity by 2,680 MT/day
Cumulative savings of over ₹ 10 crore in FY 2023-24
+22% increase in rock hoisting over the previous fiscal year
AWARDS & RECOGNITIONS
Bagged 1st prize in ‘Systematic and Scientific Development’, 2nd Prize in ‘Overall Performance’, ‘Mineral Beneficiation’ & ‘Digitalization’ at the 34th Mines Environment & Mineral Conservation Week 2023-24, held under the aegis of Indian Bureau of Mines - Ajmer Region
Won the “Vedanta Sesa Goa Mining Innovation Award” from the Federation of Indian Mineral Industries for year 2022-23
Became the 2nd mine in India to get enrolled as a member of International Mines Rescue Body (IMRB), lending Hindustan Zinc the same distinction
CASE STUDY
Undertaking seismic monitoring to prevent mishaps
We have installed five seismic geophones at various locations in SKM to minimise the incumbent stress of overlying strata and prevent sudden mishaps. Deep mines face the threat of several micro and major seismic events during mining operations. At SKM, we have many structures running from the surface to a depth of 1,000 metres below the surface. If any seismic event or movement takes place in these structures due to stress or fault slip, the absence of seismic monitoring makes it difficult to ascertain the location of the movement trigger, amount of energy released, its source mechanism, etc. Underground mines around the world are now adopting seismic monitoring mechanisms, which has become an integral tool for the effective management of ground-related hazards.
Key features
Combination of uniaxial & triaxial sensors is being used in the 5 seismic deep bore hole geophones installed in the initial stage
Numerical simulation undertaken for sensitivity array to identify the exact location of sensors
All sensors connected to the mine station through cable connection, followed by WiFi connection of the mine station to the surface server
Review of all major events by seismologists at the Institute of Mine Seismology (IMS), Australia through remote server
Auto generation of mails of all major events, detailing the location & magnitude of the event
Key outcome
Real-time monitoring & data enabling geotechnical engineers to predict any unsafe ground condition underground to activate TARP (Trigger-Action-Response-Plan) to prevent unforeseen incidents
Need for complete evacuation of the mine in case of large seismic event has been eliminated, since exact coordinates enable TARP activation only in the affected area
TARP is a unique initiative of SKM to define the minimum set of corrective actions that are required by site personnel in response to unpredicted impacts or deviation from normalcy in the mine conditions.
CASE STUDY
Innovative backfilling to fill mine voids
At SKM, we have commissioned +100 metres incline hole (+75 metres vertical) for backfilling the SK area to employ more tailings in the mine instead of sending the same to the tailing dam. This cost-effective and environment-positive initiative is a milestone in the mine’s sustainable growth journey.
Key features
Bore hole is designed for negative discharge of backfill up to +75 metres vertical height
Flow at paste-fill plant regularised to avoid choking of existing backfill reticulation and bursting of the pipeline
Flow model has been developed to push the backfill above +75 metres height
Key outcome
Improvement in tailing utilisation, enabling cost reduction
Savings in the cost of the project relating to filling up of the area with conventional methods (including plant, pipeline, borehole and manpower related cost), and reduction in dry stacking cost at tailing dam
