How to improve grinding plant performance when considering environmental, social and governance targets

As the need for mining and aggregates products continues to grow, plant operators, equipment manufacturers, vendors and customers alike are taking greater interest in how products and materials are sourced, produced and operated and choosing sustainable options wherever possible. With this in mind, operators must consider environmental, social and governance (ESG) targets as an indispensable part of any process improvement plan.

Resource efficiency, CO₂ emissions reduction, machine availability, performance, safe operations and accountable sampling present opportunities for operators to enhance plant processes that reflect ESG goals. Across the mining and aggregates processing lifecycle, the comminution process — where large rocks are turned into small rocks — is the most energy-intensive part of traditional concentrator plants. So how can plant operators use ESG targets to enhance operations? Here are a few options to consider.

Asset health monitoring and liner optimization

Professional consultation, process automation and digital solutions can serve as important elements in optimizing minerals processing circuits for sustainability. Whether focused on a single piece of equipment or a complete processing circuit, technical expertise and digital capabilities can be applied in-person or remotely to monitor and support operations through the entire plant lifecycle. Monitoring solutions are scalable, from a single circuit to a mine-to-market review, giving greater impact to optimization efforts.

As an example, when remote monitoring captured a potential mill failure on site in Asia, data exposed abnormal issues in the mill drive train. By detecting the issue early, plant personnel were able to schedule a stoppage to prevent damage to the pinion and other major components, resulting in considerable maintenance cost savings and the CO₂ emissions required to manufacture and transport new component parts.

Wear parts also offer ESG opportunities. Liner performance and wear monitoring can extend liner lifecycles and improve throughput and uptime. For example, if liners can be optimized to last longer, a mining operation may only end up using two sets of liner in a given year instead of three, resulting in less waste. In addition, recyclable mill liner materials may allow rubber and steel elements of worn liners to be removed and reused or recycled as raw material for new liners and prevent disposal in landfills.

Upgrades and modernizations

Production means profit, and evolving technology continues to deliver innovative tools and solutions that can keep systems and equipment operating at their peak. Whether to extend equipment service life, improve performance, enhance efficiency, increase availability, improve safety or maximize return on investment and cash flow, component and equipment upgrades and modernizations can take processes to the next level and help to achieve ESG targets. For example, if more production is required from a circuit, upgrading existing equipment could be an economical option, which also saves on the embedded carbon produced such as when manufacturing new components or equipment.

Upgrades may be standard or custom-engineered to individual needs. Mechanical upgrades can enhance performance, energy efficiency and equipment reliability, while controls/electrical modernizations can improve safety and efficiency.

Grinding mills often require accumulator units to maintain bearing pad lubrication and prevent the pad from running dry and damaging the mill during unexpected events such as electrical power outages. Comprised of the lubrication unit, gauges and pressurized nitrogen tanks, these systems occupy a large footprint, require ongoing maintenance and can take equipment offline in the event of failure. A polymer bearing pad upgrade not only ensures consistent hydrostatic pressure, mechanical reliability and longevity, but also eliminates the need for accumulator circuits and the associated unplanned downtime. The pads’ sustained elasticity has proven to enhance mill availability and reduce maintenance costs over babbitted bearings.

For example, when a mill required an emergency shutdown several months after a set of polymer bearings were installed at a customer site, all auxiliary equipment was successfully stopped, however, the main mill motor circuit breaker failed to cut power to the motor due to a pre-existing and undetected fault in the breaker assembly. As a result, the mill continued to rotate for approximately 10 minutes with no oil supply to the polymer HSB bearings.

After stopping the mill, the circuit breaker was repaired and the lubrication systems restarted. Mill instruments gave no indication of bearing damage or performance loss, and the mill resumed operation. Following three years of operation following the incident, no adverse effects were noted to the polymer HSB system.

Reuse and recycle

New equipment can provide high performance and act as a channel for growth. But today’s extended manufacturing lead times and limited budgets make surplus and second-hand equipment an option in certain applications.

Using surplus equipment saves CO₂ through the circular economy may drastically reduce lead times. A surplus equipment broker can provide access to lower-priced premium assets, help operators repurpose equipment into new applications and help to meet a plant’s ESG targets. Surplus or unused equipment can be considered at any point in a plant lifecycle, from a major equipment change to a greenfield project.

To help operators achieve ESG goals, Metso and surplus mining equipment broker AM King have entered into the industry’s first global partnership for upgrades, parts and field services for AM King surplus equipment sales, regardless of manufacturer. Whether servicing original or third-party equipment, the partnership provides OEM support for wholistic, turnkey customer support.

Options designed for flexibility

When it comes to environmental, social and governance-friendly options to improve mining and aggregate plant process performance and production, there are several options to consider. Decisions may depend on timing, budget, material type, plant size, site conditions or operation lifespan. Investing in new equipment and technologies can also provide advantages in plant process performance. Metso provides capital and aftermarket products and services for OEM and third-party equipment to help operators achieve production targets and sustainability goals.

Metso is a frontrunner in providing sustainable technologies, end-to-end solutions and services for the aggregates, minerals processing and metals refining industries globally. Central to our efforts is Planet Positive, a portfolio of over 100 products and services designed to improve our customers’ processes during modernizations and upgrades, as well as optimize existing production processes.