Aggregates such as crushed stone, gravel and sand are the backbone of construction globally – quietly underpinning the success of infrastructure development programmes – making them one of the most important materials in the modern world.
In fact, sand is said to be the second largest natural resource by volume after water and accounts for the largest volume of solid material extracted globally. To provide context, The United Nations notes that demand for sand has grown three-fold over the past two decades, with the world now needing 50-billion tonnes per year, an average of 18 kg per person per day.
The increasing discrepancy between the need for aggregates in society and the scarcity of natural sand (the result of exhaustion of resources and environmental considerations), has pushed the industry to look for a suitable and sustainable alternative fine aggregate. Manufactured sand has therefore come to the fore as the most economical and ecological alternative.
Amid this transition to manufactured sand, Pilot Crushtec Intranational has over the years positioned itself as a leading solutions provider for the sand manufacturing market in southern Africa, offering a comprehensive range of cutting-edge solutions for efficient and sustainable sand manufacturing.
Leveraging 35 years of expertise in the mining and aggregates industries, the company has developed a range of standard, ready-to-run sand making plants. The Pilot SMP line of sand manufacturing plants benefits from a comprehensive and proven range of feeders, crushers, screens and conveyors.
This is complemented by the DynamiTrac HRC8 tracked high pressure grinding roll (HPGR) crusher, which takes sand-making to the next level by producing significantly more fines than conventional crushing, while offering improved shape and gradation at a much lower cost of operation.
Pilot SMP range
Sand producers seeking a quick route to production can choose from three sand-making plants, engineered for quick setup and consistent performance. The range comprises the SMP100, SMP200 and SMP300.
The SMP100 – the smallest in the range – can produce up to 40 tonnes per hour (tph) of -5 mm sand with a maximum recirculating load capacity of 85 tph through the rotor. This compact plant can take 5-25 mm feed when equipped with a 600-mm rotor or a 5-35 mm feed size with a 700 mm rotor.
The mid-size SMP200 can produce up to 55 tph of -5 mm sand with a maximum recirculating load of 120 tph through the rotor. This plant can take 5-30 mm feed material with a 700 mm rotor and a feed size of 5-45 mm with an 800 mm rotor. The largest in the range is the SMP300, which produces up to 100 tph of –5 mm sand with a maximum recirculating load capacity of 280 tph through the rotor.
Benefits abound
One of the key advantages of these sand-making plants, explains Francois Marais, sales and marketing director at Pilot Crushtec, is that they are designed as a complete, ready-to-run solution, thus offering fast setup and deployment.
“These plants are pre-engineered and ready to go, meaning that one can get them up and running much quicker than bespoke solutions. There is no need for lengthy design phases – it is just a matter of assembling and starting to produce,” says Marais.
Another major benefit of going the Pilot SMP plant route is cost-efficiency. As a leading original equipment manufacturer (OEM) in South Africa, Pilot Crushtec has paid its school fees in the design and manufacture of comminution solutions over the past 35 years, which means that customers do not have to foot the costly bill for custom engineering. This translates into reduced upfront capital costs and reduces the risk of budget overruns.
With these engineered designs proven in the field for over three decades, customers can maximise their operational uptime through proven reliability. “Our standard SMP plants are built from tried-and-tested designs. They have been refined over the years to work seamlessly across various applications, thus eliminating the risk of unexpected breakdowns and inefficiencies,” says Marais.
With flexibility in mind, these plants are designed to handle a range of tonnages across applications such as sand making, aggregate processing, or even specialised processes. These solutions are also scalable, suiting the needs for customers who require to increase capacity as and when demand dictates.
With standard designs, parts are off the shelf and easily available from Pilot Crushtec’s established support network. Plant uptime is further maximised by the minimal site preparation requirements. All modules are skid-mounted and designed to work on a flat, compacted surface, although a concrete base can be more beneficial.
To be successful in sand production, the equipment must be of a high standard to ensure consistent and efficient production. The Pilot SMP plants are manufactured at Pilot Crushtec’s ISO-accredited Jet Park facility in Johannesburg, South Africa. The proven quality of the plants reduces downtime and maximises output, thus mitigating against risks that could undermine a project’s viability or dampen the producer’s reputation in the market.
New way of sand making
In addition to the SMP plants, Pilot Crushtec now offers its DynamiTrac HRC8, the world’s first fully track-mounted, dual power HPGR crusher ideal for use in quaternary crushing applications. At the heart of this machine is the Metso HRC 8 HPGR crusher, which employs a completely different crushing principle from other conventional solutions such as impact crushing.
The HRC 8 uses a method of inter-particle comminution by drawing in a bed of material between two rotating rollers. The rollers, one of which is in a fixed position and another floating, generate an extremely high pressure that is applied to the layer of material between the rolls, extruding the feed material down to the desired smaller grain sizes. The HRC 8’s adjustable pressure allows customers to vary the curve grading for finer or more coarse grading.
“Customers can obtain much better grain proportions with the new HRC technology, as well as control in the manufactured sand gradation with a very good particle shape and less ultra-fines generation,” explains Marais.
Ultimate sand maker
The HRC 8, adds Marais, is the ultimate solution for the manufactured sand market where fines must meet a defined end product specification. The quality of sand can be adjusted and optimised, thus reducing the amount of cement and asphalt required in concrete mixes or asphalt. The machine produces a gradation according to customer needs and delivers a perfect cubical shape for concrete and asphalt sands.
In some applications, non-saleable waste materials can be reprocessed by the HRC 8 to correct the gradation curve and particle shape, converting them into high-value saleable products. This not only addresses the cost factor, but also speaks to the manufactured sand sector’s drive for sustainable operation.
“In typical sand-making with vertical shaft impactors (VSIs), for example, there is generally a high percentage of ultra fines – the unwanted 0,075 micron material, which calls for wet processing. Due to its ability to produce very fine material with fewer unwanted microfines in the final product, we believe that in some applications, the HRC 8 may eliminate the requirement for washing,” explains Marais.
The tracked DynamiTrac HRC8 from Pilot Crushtec is powered by a 250-kW on-board Volvo TAD851GE diesel generator engine available in Euro Stage 3 or Euro Stage 5 emission controls. The Deepsea electric genset controller allows for switching between generator and grid power, when available. The crusher is controlled by the Metso IC80C automation system that ensures and manages consistent feed into the crusher to ensure optimal energy efficiency and maximum production.
“The reduced power required to run the machine compared to traditional impact and even cone crushers is another big benefit of the HRC 8. To provide context, where customers would traditionally require 250-300 kW of power to produce 50 t of manufactured sand, they now use only 120 kW with the HRC technology. In fact, the machine consumes up to 50% less power in sand production compared to other technologies for the same volume of net product,” concludes Marais.
