WITH less than 10% of all general waste being recycled in South Africa, almost 100-million tons of municipal waste is dumped at hundreds of landfill sites across the country every year.
That’s according to Jay Moodley, Regional General Manager at Babcock, citing Department of Energy figures. He added that once full, many of these landfill sites will be used for building housing estates, malls, office blocks or other developments and that various processes and equipment are required to ensure the integrity of the ground for future building on these sites.
Moodley said that Volvo articulated dump trucks (ADTs) are playing a pivotal role in this specialised process at four landfill sites in KwaZulu-Natal.
Ethekwini Municipality’s Durban Solid Waste (DSW) department has invested in 22 30-ton Volvo articulated dump trucks (ADTs) to be used at the landfill sites. DSW took delivery of eight A30G trucks in June 2021, with a further eight trucks delivered on 6 October at the official handover ceremony. The rest of the trucks will be delivered early next year.
Supplied by Babcock, the exclusive distributor of Volvo Construction Equipment in southern Africa, the A30G dump trucks are being used as standard ADTs, water tankers and for hoisting of skips with hook lifts.
Moodley said the 30-ton Volvo ADTs are the ideal dump trucks for a landfill environment as they are purpose-built for these types of conditions, have sufficient capacity for the volumes required to move for this application, and are easy to manoeuvre on roads as well as the landfill sites.
“Ensuring the future integrity of the landfill ground hinges on the quality and efficiency of the products and processes used. While the equipment is just one element of the process to extend the life of a landfill site, using the right equipment and quality machinery to get the job done safely can prevent incorrect compaction, development of manholes or sinking of a compacted area when it may be used for building years later.”
In their simplest application for DSW, some of the Volvo A30G dump trucks are being used for hauling and moving of waste within the landfill sites after being loaded by excavators or front-end loaders.
Others have been modified as hook lifts to lift skips from waste removal trucks and transport them to be offloaded.
“Garbage is brought to a drop-off zone by road trucks that cannot access landfill sites due to rubble and uneven dirt roads. The skips are lifted on to the back of the ADT and are transported to the landfill sites where they are then offloaded.”
Babcock partnered with ETT to undertake the modifications, a company that specialises in professionally engineered special vehicle solutions for mobile industrial equipment.
ETT also assisted Babcock to convert some of the trucks to water tankers, which are necessary for watering down the dirt roads leading to the landfill sites to prevent dust from rising, keeping the air clear and watering down any contaminants.
“The water tankers are also used to wash down the actual landfill area between compacting to achieve maximum compression, which is essential should the land be used for building at a future date,” said Moodley.
To prepare the trucks for the harsh, toxic landfill site conditions, a number of modifications were made to all the trucks. Landfill sites produce high amounts of methane during the decomposition process, which can be a flammable hazard. Babcock partnered with Fogmaker to fit fire suppression systems in the cabs and engines to protect drivers and the essential parts of the trucks in the event of a fire.
The trucks were also fitted with an auto-greasing system to ensure that all the moving or wear parts are greased regularly. Moodley explained that the system creates a constant flow of grease to the moving parts to ensure that the friction on wearing parts is reduced so that they last much longer.
“On a landfill site there is a lot of moisture, and different materials such as sand, rubble and chemicals that could be highly corrosive to the moving parts, so it is important that these parts are coated in grease to promote longevity.”
He said reverse camera systems were installed at the rear of all the ADTs to enable drivers to clearly see any obstructions or people behind the large trucks, which are constantly reversing on site. To further increase visibility, particularly at night, additional LED lighting was installed above the canopy.
Moodley said Babcock worked closely with DSW to undertake these modifications. “DSW has invested substantially in the knowledge, research, social impact and environmental impact studies with regard to safely managing waste. They understand the challenges of landfill sites and have set out specific requirements that are essential for all stakeholders operating safely on site. Babcock has the flexibility to modify equipment, and we partner with leading suppliers to meet our clients’ stringent criteria.”