Mining engineers and plant managers oversee a wide range of environmental compliance responsibilities, including the management of slurries, ore processing streams, and the water used for separation, cooling, dust suppression, and washdowns. Advanced filtration is also critical for treating water strained from pits, sumps, wash bays, stormwater collection points, milling, beneficiation, and chemical leaching processes. As a result, dependable automatic scraper strainers play an important role in maintaining uptime while supporting broader water management and compliance goals.
Today, automatic scraper strainers are among the closest solutions to a true “set-and-forget” system, effectively removing both large and fine suspended solids from mine water, process water, cooling tower water, liquids, and slurries.
The basic design represents one of the most efficient and cost-effective industrial self-cleaning strainers available. The motorized unit is engineered for minimal maintenance and operator involvement and can remove solids as small as 75 microns. These strainers allow for continuous, uninterrupted flow, including during blowdown cycles.
Cleaning is performed by a spring-loaded blade and brush system controlled by a fully automatic control unit. The two blades and two brushes rotate at 8 RPM, for a total of 32 passes per minute. The scraper brushes penetrate the wedge-wire slots to dislodge stubborn particulates and adhered solids.
However, incorporating minor customizations or application-specific modifications can further optimize the automatic scraper strainer’s performance and suitability for a given mining application, according to Robert Presser, President of Acme Engineering Products, Inc., a North American manufacturer of industrial self-cleaning strainers.
Choose the Screen Best Suited to the Application
Reverse formed wedge wire screens are the most common screen type used due to their strength, durability and resistance to deformation resulting from high differential pressures. The smooth continuous slot profile minimizes particle wedging and facilitates the use of automated brush cleaning systems.
For processes that require finer filtration, multilayer sintered metal mesh screens are a good option. These screens consist of multiple layers of woven wire mesh bonded together to form a rigid, porous structure.
Add a Macerator to Break Up Large Solids
For applications with high solids loading that are prone to clogging, a macerator can be installed upstream of the automated scraper strainer. This solution accommodates heavy solids loading while ensuring uninterrupted flow and dependable, clog-free performance.
Specify Fiber-Reinforced Plastic (FRP) Construction
When the chemical properties and temperature of the process fluid raise concerns about material compatibility, automated scraper strainers are available in other materials such as Monel, D2205, SD2507, and even Fiber-Reinforced Plastic (FRP). The internal mechanism and wetted components can be manufactured from super duplex or similar high-performance steels.
Given the wide range of fluids encountered in mining applications, selected materials must resist pH variation, dissolved metals, chlorides, sulfates, abrasiveness, and operating temperatures, while also meeting pressure and flow requirements.
For these reasons, duplex or super duplex stainless-steel construction is used to resist corrosion, but at considerable cost. However, a much more cost-effective option is to utilize Fiber-Reinforced Plastic (FRP) strainers that are specifically designed to be resistant to corrosive environments at a fraction of the cost.
For mining and mineral processors, automatic scraper strainers can offer a far more stable answer to solids separation in applications where conventional screens struggle with heavy loading, changing flow conditions, or persistent fouling. Continuous self-cleaning reduces the need for manual intervention, helping plants avoid unnecessary downtime and maintenance.
For more info, visit Acme Engineering Prod. Inc. at acmeprod.com; phone Philippe Ellison, Project Manager at: +1-518-236-5659; email phil@acmeprod.com. In Canada phone: +1-514-342-5656.