Gallagher’s Hermitage Quarry reduces their carbon footprint with the help of PowerX Equipment.

By John Vincent...

Hermitage Quarry is located in Maidstone, Kent and is one of only two processing operations actively quarrying Kentish Ragstone. Owned and operated by Gallagher Aggregates Ltd who are at the heart of the Gallagher Group. Hermitage Quarry has the capability to produce up to 1 million tonnes of aggregate per annum, which are processed into more than 70 different construction materials. Gallagher also operate six concrete plants, supplied mainly by their own indigenous aggregates. Additionally, Gallagher operate a modern recycling facility at Hermitage Quarry which processes construction and demolition waste into a range of recycled aggregates in addition to an active Landfill facility that accepts inert waste which cannot be recycled to fill the void left by quarrying back to original levels. 

Hermitage Quarry features two benches, which are drilled and blasted by conventional techniques and the as blasted material is loaded and hauled to the processing plant that features a Hercules trommel, which efficiently segregates the interbedded nature of the deposit. The material is then processed and washed into aggregates through a series of crushers, screens, log washers and cyclones.

All these operations including drilling and blasting are conducted by the in-house Gallagher team.

The new conveyor installation:

Having previously visited the quarry almost twenty years ago to view the then new wash plant [which had been installed by PowerX Engineers] it was interesting to view the recent changes in operation today.

I met Dave Scanlan the Quarry Manager who took me on a tour of the quarry.

Recently modifications have been made to the stockpile feed from the wash plant.

Dave, commented, “We had recently installed a new state of the art concrete plant on-site and we made the decision to move the aggregate closer to the new plant to make the process more efficient and most importantly reduce our carbon footprint. We were using dump trucks and wheeled loaders to haul the washed and rinsed aggregate from the wash plant to the concrete plant bins, so we decided to make some changes and turn the second screen to feed off on the left-hand side onto three transfer conveyors. This eliminated one dump truck and one loading shovel from the process”

We had previously engaged PowerX Equipment on several projects over the years and we viewed them as a tried and tested company, very skilled in what they design and offer. Subsequently they were given the order to design and commission the three new conveyors, feed hoppers and supporting structures complete with safety walkways, improving access and egress.”

At this time, new aggregate storage bays and the concrete foundations for the new transfer gantries were completed by the in-house Gallagher team.

Installed and commissioned within a time frame of two weeks the three 800mm wide transfer conveyors, each approximately 30 metres in length are supported by a modular galvanised support structure and feature fully guarded 800mm steel emergency walkways and include head and tail drums with maintenance platform.

Specifically in line with Gallagher’s philosophy on Air and material quality, the conveyors are also fully covered.

On an average day, the wash plant processes in the region of 2,000 tons with the new no 1 transfer conveyor handling the sharp sand, with washed 10mm aggregate on conveyor no 2, and washed 20mm aggregate on conveyor no 3. The finished 3 products are generally consumed within Gallaghers concrete business or supplied to the external market for pipe bedding and block manufacture.

Dave, concluded, “Pat Gallagher and the family always invest in the best equipment, and it is credit to PowerX Equipment that the installation does “exactly what it says on the tin.” If you look at the original wash plant [Since installation has processed 9 million tonnes] we have only had to upgrade two screens in the last 8 years and apart from the usual wear and tear the 20-year-old plant is solid. An adjacent logwasher which had reached ‘end of life’ was replaced two years ago and again PowerX did a thoroughly competent job with the supply and installation!

“The PowerX team are first class with a huge commitment to Health and Safety, with all their team well trained, competent and knowledgeable. The project was completed easily within the time frame, and we are very pleased with the final outcome.”