With several quarries and recycling centres around Leeds, Mone Brothers has a long tradition in mineral recycling. Since it was founded in 1965, the business quickly developed from a simple plant hire company into one of the principal providers of construction materials and recycling services in West Yorkshire.
In minute intervals, dumper trucks drive into the near 2.5-hectare Fireclay recycling centre site, bringing mixed rubble from demolition work and construction sites and taking back crushed and cleaned material. On average, more than 300,000 tonnes of this material are processed here every year. While broken bricks are recycled into hardcore according to British Standard 6F2 and used primarily as a capping layer in road construction, the recycled concrete is used as a higher quality Type 1 layer for sub-base purposes.
Furthermore, Mone Brothers works a great deal with the local utility industry and supports the expansion of the electricity, water and gas network with its material. The companies deliver their mixed rubble and drive away again with recycled Type 1.
The different feed materials and required quality standards have an impact on the production process. Thanks to a higher permissible oversize grain content, it is possible to dispense with a closed circuit for 6F2 and in doing so increase the feed capacity. In this configuration, the MOBIREX MR 110 Z EVO2 of Mone Brothers has a capacity of 280 tonnes per hour.
For the recycled Type 1 material, the system changes its location in just a few minutes and the secondary screening unit is mounted in around 15 minutes. With the integrated oversize grain return conveyor, the capacity for this classified product is still 250 tonnes per hour while also meeting the highest standards in British road construction.
These products are typically produced in the UK with jaw crushers, and Mone Brothers also has one from Kleemann working on quarry applications. However, the decision to opt for an impact crusher for use at Fireclay recycling centre was made for a good reason.
Michael Coleman, managing director at Mone Brothers, says the final product quality has significantly increased. The impact crusher achieves a grain shape in one crushing stage that a jaw crusher could not come close to without a second crushing stage. The slightly higher fine content helps to bind the material during later use and therefore also equates to the required quantity.
In addition to product quality, the higher performance of the MOBIREX is also a highlight. While jaw crushers offer a recommended crushing ratio of 7:1 in recycling, impact crushers can achieve a ratio of 15:1 and thereby a greater feed size, which facilitates significantly higher performance.
"The output is truly mesmerising and it has been a real benefit to the business," says Coleman.
It is therefore easy to work out why Mone Brothers replaced two of its jaw crushers with just one impact crusher. Thanks to the diesel-direct-electric drive concept of the MR 110 Z EVO2 impact crusher, this is said to reduce what were already low operating costs by another 15%.
Despite many years of cooperation and positive experiences with the aftersales service, Coleman says the decision to invest in a Kleemann impact crusher was not a matter of course. "We did try other machines but actually they could not produce enough of the product at the right speed and they were much more expensive to operate.”
