Scaling up screening performance

The full article was first published in Dry Bulk magazine online during February 2025

Screening is a critical part of most mining and aggregates operations, often determining the final product’s gradation and quality as well as playing a vital role in ensuring production and throughput rates. Its efficiency directly impacts overall cost-effectiveness and operational performance. Prioritising decisions about screening equipment, media and operational factors can significantly reduce costs, enhance uptime, and optimise results. Even so, screening often receives less attention than crushing or other processing equipment selection.

Screening involves separating materials through screens or meshes to achieve uniformity in gravel, sand and crushed stone for further processing or direct use. The two key considerations when setting up your screening operation are preparation and choosing the right equipment. Read more below.

Preparation: collecting data for better decisions

The best place to start is by gathering and analysing information about the screening operation you plan to set up. Although the resources available for this step will vary according to the size and maturity of your business, it is always worth properly exploring the technologies available to support your decision-making process.

Process simulation

By allowing virtual testing instead of physical trials, process simulation tools can save time and resources later on. They can help you select the best equipment for specific materials and production goals and predict how adjustments in set-up or equipment selection would affect performance, such as production capacity, throughput and product gradation, as well as operational costs. For example, Metso’s Bruno software saves time and resources by identifying the best equipment for specific materials and production goals.

Lab tests

Run independently or used to confirm the results of a process simulation, lab tests can also play a valuable part in designing effective screening solutions for mining and aggregates. By providing critical data on material properties and behaviour, they make it possible to tailor screening processes and equipment to specific requirements. Lab tests are available for a range of applications, such as dry fine screening, wet fine screening, and traditional wet or dry screen testing. The results from the lab tests can be used to guide your decisions on screen type, aperture size and shape, screen deck configuration and material handling.

Choosing the right screening equipment

The wide array of screening equipment can be overwhelming, but you can narrow down your options by asking a few critical questions.

Mining or aggregates?

Since mining operations are characterised by high tonnage and 24/7 usage, they require heavy duty machines that can be relied upon to keep going between planned shutdowns. Key priorities are high availability and capacity, as well as ease of maintenance and availability of wear parts. Some examples of screening equipment designed to support the high capacity and mechanical availability required for mining operations are conventional inclined and horizontal screens, box exciter banana screens, dewatering screens, and high-frequency screens. Each one has a different stroke pattern (circular, linear or elliptical motion) to fit a specific application.

If your screening solution is intended for aggregate production, the equipment will typically be operating for eight hours per day, rather than round the clock. With less heavy use, your screens will last longer, so wear and tear will be a lower priority. For aggregates, we therefore generally recommend horizontal equipment that has a low and compact profile and gives high quality separation efficiency.

Stationary or mobile equipment?

Stationary screening equipment is ideal for high-production mining applications since it can handle large volumes, integrates well with other equipment, and offers high precision production with lower long-term maintenance costs. Mobile equipment, on the other hand, is more suitable for aggregate production due to portability, lower initial investment, flexibility and minimal set-up time.

Wet or dry materials?

Screening sticky, high-moisture materials is challenging, often requiring water for processing. However, environmental regulations and rising water costs have prompted the development of sustainable innovations like Metso’s Banana Screen Efficiency (BSE) and Efficient Screening (EF) technologies. Combining banana/multi-slope screens, elliptical motion, and flexible rubber media makes it possible to effectively screen sticky materials with minimal or no water.