A claimed aggregate recycling first and the growth of the sector in European countries including Germany and the UK. Guy Woodford reports.
The claimed world’s largest wet processing plant for construction and demolition waste built by
More than 70 companies from Norway, Sweden, Denmark and Tunisia were in attendance at the Velde Pukk site.
The new 300tonnes/hour washing plant for construction and demolition waste was purchased by Velde Pukk in late 2014 and is said to be the first of its kind in Norway. “We opened discussions with CDE a number of years ago as we see the huge opportunity presented by the recycling of construction and demolition (C&D) waste to high-quality, high-value recycled sand and aggregates with a wide range of applications,” says Egil Velde, managing director of Velde Pukk. “We visited a number of existing CDE installations and have watched very closely the technological innovations from CDE in recent years, which combine to maximise material quality and minimise waste from the process.”
As well as processing C&D waste received at the Sandnes quarry, the new CDE plant is also processing overburden from the company’s hard rock quarry operations at the same site. The CDE project was initially led by Eoin Heron, CDE regional director for Europe and Russia, and he says that the flexibility offered by the CDE equipment was an important factor in winning the project. “We looked at the overburden for Velde and determined that we could design a plant that would allow them to not only recycle the C&D waste but also to recover material from the overburden which could subsequently be used in their integrated operations.”
As well as operating the quarry in Sandnes, Velde also specialise in the production of ready-mixed concrete, asphalt production and laying and have their own transport fleet which are very apparent on any trip around the Sandnes and Stavanger areas.
The North Sea oil industry is a big driver for the economy in this part of Norway and the short trip from Stavanger airport to the quarry in Sandnes reveals a huge amount of infrastructure development on the ground, matched only by the number of helicopters you see transporting people and parts back and forward from the oil rigs off the coast.
“We are a well-established and respected name in this area and are providing material to a large number of local projects on a daily basis” explains Velde. “Our investment in the first wet processing plant for C&D waste in Norway is a symbol of our success - people expect innovation from our company because of our history and we hope that our investment in the CDE plant is taken as a symbol of the potential that exists for this highly valuable resource to be turned into high-quality, high-value recycled sand and aggregates.”
This partnership approach between Velde and CDE allowed for significant efficiencies to be enjoyed during the project delivery phase. The CDE project manager on this job was Colum Bryson and he believes the level of engagement with the Velde brothers and the wider operations team in Sandnes was critical to a successful plant installation.
“This is one of the largest mechanical installations that CDE has ever completed and as with all projects there were some very specific challenges to overcome during the design and delivery phase” explains Bryson. “Sandnes quarry is a very busy working site so the installation and commissioning phase had to be managed with respect for the essential daily operations of the crushed rock processing plant, the ready-mixed concrete plant and the asphalt production plant. Thanks to the engagement and commitment of the full team at Velde, we were able to not only manage these issues but actually reduce project delivery time by 40%.”
A total of 55 lorries were involved in the transportation phase to deliver the new washing plant to Sandnes quarry, and due to limitations on space it was essential that staged deliveries were organised. It was also essential that this was done in such a way as to minimise crane hire requirements on site.
The Velde commitment to doing everything the right way is immediately apparent whenever you visit Sandnes quarry and see the work that has gone into the civils on which the plant is located. A concrete pad was constructed as well as a variety of concrete product bays built to facilitate the introduction of the many radial product conveyors on the plant. “The concrete pad at Sandnes quarry is an example of how all projects such as this should be accommodated” says Bryson. “The long-term benefits of this are huge - easier and more efficient movement of site vehicles around the site and quick, easy and safe access for essential plant inspection and maintenance.”
The specification of several radial stockpile conveyors for the washed recycled sand and aggregates is another example of the Velde commitment to minimising the environmental impact of their operations. “This has the effect of significantly reducing transport movements onsite, bringing significant cost savings,” explains Harald Velde, operations director at Velde. “This also eliminates unnecessary double handling of our products. In addition to the cost benefits, the reduction in transport movements also reduces health and safety risks on site - safer, happier people are more productive people, and this was a big factor for both us and CDE in the design of our new plant.”
The groundbreaking CDE Global solution for Velde Pukk is operated highly efficiently.
Feed material is delivered from the feed hopper to two side-by-side R2500 primary screening units with integrated apron feeders that split the feed across two separate 150tonnes/hour processing lines. Any +90mm material is removed via a double deck 5m x 1.5m grizzly screen. The remaining material is discharged to two horizontal feed conveyors.
The 0-90mm material then arrives at two AggMax 151 modular logwashers where a pre-screen removes all the 0-4mm material which is delivered directly to the EvoWash 201 sand washing plant. “The pre-screen is essential at this stage to ensure the efficient operation of the AggMax” explains Eoin Heron. “Not only does it ensure that the aggregate fraction is satisfactorily scrubbed, it minimises wear in the AggMax and maximises sand production.”
After aggressive scrubbing in the two AggMax units, the 4mm-90mm recycled aggregate is sent to a ProGrade P2-108 sizing screen. The two AggMax machines also include a trash screen at the rear which removes any lightweight and organic contamination from the recycled aggregate product. Any sand liberated during the attrition phase is also sent to the EvoWash sand washing plant, ensuring maximum product yield from the C&D waste feed.
The ProGrade P2-108 sizing screen is from the new Infinity screening range from CDE. It includes a patented side wall construction said to remove unnecessary weight and reduce the power required to run the screen. The screen is set up to produce 4mm-11mm, 11mm-16mm, 16mm-22mm and 22mm-90mm products, all of which are stockpiled using static and radial stockpile conveyors. The EvoWash sand washing plant produces two grades of sand – a 0-2mm and 2-4mm. The 0-2mm product is used in the asphalt production plant at Sandnes quarry, while the 2-4mm product is used in the concrete plant.
Given the space restrictions on site it was essential that full water recycling and sludge management was included on the new Velde Pukk plant. There is no option to include settling ponds at Sandnes quarry, but the Velde commitment to minimising environmental impact meant that this was an essential requirement of the new plant anyway. “Not only does the plant require much less space with the full water and sludge management system, but the fresh water requirement is 95% less than if we simply included settling ponds. It also results in a cleaner, safer and more productive site,” explains Harald Velde.
The wastewater from the plant is first delivered to an AquaCycle A1500 thickener where it is dosed with flocculant. This forces the very fine particles of silt and clay to bind together and sink to the bottom of the tank. Meanwhile, the recycled water overflows the peripheral weir and is stored in a concrete buffer tank before being recirculated to the washing plant.
The sludge at the bottom of the AquaCycle thickener is discharged automatically at certain pressure and is sent to another concrete buffer tank which is fitted with a set of agitators to ensure a consistent sludge is delivered to the overhead beam filter press. The filter press model specified is one of the largest available and has 169 plates each measuring 2m x 2m. These plates press the sludge to remove more water before the filter cake is discharged to a bay below.
“We are currently using the filter cake – which has a dry solids content in excess of 80% - for the construction of embankments which means that we have eliminated waste from this stage of the process” explains Harald Velde. “Of the 300tonnes per hour feed to the plant the only waste from the process is made up of the lightweight and organic contamination removed during the attrition phase.”
The new CDE plant at Sandnes quarry will divert approximately 600,000tonnes of C&D waste from landfill every year. Velde Pukk aim to develop the market for recycled material in Norway in the months and years ahead through extensive testing and use of material in their own operations.
Juha Tiilikka, the company’s global sales support, aggregates business line, says he has seen strong growth in aggregate recycling.
“Western Europe, particularly Germany and the UK, is very strong in this area,” says Tiilikka. “Scandinavia is not currently so much for recycling. Due to high transport costs as a result of the region’s infrastructure being so widespread, the economic value of recycling has not been good.”
Tiilikka says environmental legislation is making companies do more recycling as part of a wider green agenda. He says more recycling is done onsite such as asphalt recycling, for example, on highway projects. “This is also cutting transport costs, making it better value for money,” he adds.
Whereas previously 15% of aggregate material was recycled on any given building construction or highways project, Tiilikka says it’s now closer to 30%. The final recycled material is now increasingly cleaner, he notes.
“Lower diesel fuel costs and better fuel efficiency of recycling plants is also making aggregates recycling more economical,” continues Tiilikka. “In future there will be greater demand for recycling equipment. More recycling will be done closer to urban areas, as operators conform to noise and dust emissions regulations. More and more onsite recycling will then take place, lowering transport costs.”
Andrew Bolton,
“There’s definitely within Europe more and more pressure for companies to avoid using landfill,” says Bolton, who was talking to Aggregates Business magazines during
“In the shingle market in the US, road planers are reusing the material and putting it back there and then,” adds Bolton. “We can provide a wide range of machines for recycling that can be adapted for different jobs.”
For its new recycling plant near Vienna, Austrian firm Schneps has installed a new CI521 Prisec horizontal shaft impact crusher from Sandvik Construction.
Following intense discussions and planning meetings between Schneps, BAG and Sandvik, a flowchart was created using the Sandvik PlantDesigner software. This created a virtual plant tuned to Schneps’ exact requirements and needs. At the core of the newly designed recycling plant is the Sandvik Prisec CI521 horizontal shaft impactor. This new generation of compact horizontal shaft impactors (HSI) from Sandvik Construction is said to combine low investment costs with the highest performance. They are able to efficiently process a wide range of materials, in a variety of application areas, at a very low operating cost.
The key to this is, according to Sandvik, operational flexibility, ensured as the modular design of the Prisec series enables conversion of the equipment from primary to secondary crusher in a short time, without the use of any additional parts. The new crushing chamber configuration is said to enable a higher crushing rate than before. Additionally, and besides the improved productivity, the new crusher features universal wear parts and a low maintenance requirement.
The CI521 chosen by Schneps is equipped with two infinitely adjustable, hydraulic-operated curtains, which together with the newly developed braking system enables the corresponding impact curtain to be lifted and held in position when any uncrushable material enters the crusher.
Both the first and the second curtains are equipped with an adjustment/braking system, located on the cross-beams of the crusher. With this new generation of HSI’s, blockages, crusher downtime as well as hazards for health and safety are said by Sandvik to be kept to a minimum, resulting in maximum utilisation of the operating time.
The core components of the crusher are the rotor and the hammers. The weight and improved design of the rotor is said to easily give the crusher the inertia needed for optimum crusher performance. The modular design (banana shape) of the hammers ensures a uniform wear pattern during the entire wear or service lifetime, producing a uniform product. An additional safety aspect is the key safety interlock system, guaranteeing safe maintenance, preventing the unintentional opening of the crusher or the inspection hatches.
Things moved rapidly for Schneps: from the initial planning to the award of the contract was a mere 14 days. Following two months of plant construction work, the CI521 was installed and commissioned. With its 50 employees, Schneps is now able to efficiently deal with building waste recycling in a radius of 50-70km around Stockerau, turning this waste material into high-quality products, supplying the Austrian market in an environmentally friendly and economic manner.
In neighbouring Germany, Simmerather Recycling has found a successful operational model by combining recycling with quarrying of limestone. Both jobs can be executed with one flexible machine: Metso’s Lokotrack LT1213 impactor – with the firm’s third LT1213 recently installed.
Simmerather Recycling has its operations in the middle of picturesque countryside in North Rhine-Westphalia, close to the Belgian border. With the workforce of about 30 employees, the company processes recycling materials collected from the region around the town of Simmerath.
In addition, since 2000 the company has been processing limestone in a nearby quarry. The approximate recycling/year is 50,000tonnes and quarrying generates 100,000tonnes/year of material.
The new LT1213 was sold to Simmerather Recycling by Metso’s official distributor in Germany, Fischer-Jung.
“Flexibility and quality are the main factors securing cost-efficient operation for us. In processing of recycled materials, we emphasise high quality. When having a break in recycling, we can transport the LT1213 easily to a nearby limestone quarry for aggregates production,” comments Simmerather Recycling managing director Stephan Braun.
Simmerather Recycling is certified to the highest RCL1 level with its recycle crushing end products. The company’s main particles to recycle are asphalt, concrete and other types of demolition debris. The materials are supplied from reserves collected by Simmerather and other companies.
The basic end products crushed with the LT1213 impactor plant include 0-32mm and 0-40mm sized grades. These are mainly then used to create waterproofing and road basement layers.
“I bought my first LT1213 already in 1999, and the second one a few years later. If the machines weren’t good I would not have bought the third one,” Braun notes.
Renewed details in the new LT1213 unit include direct crusher drive, Tier 4 motors, curved feeder walls and idling motor mode when the crusher is empty, the latter feature saving vital fuel costs.
“We do expect the new model to be 20% more economical then the old one. The new IC700 process control with easy-to-use colour panel and push buttons is working well, and keeps the process flow fluent,” Braun continues.
In recycling, the capacity of the new LT1213 is around 150-160tonnes/hour, and in aggregates production 180-270 tonnes/hour.
Simmerather uses Metso’s martsensitic alloy steel blow bars on its LT1213 models. Parts and service are handled by Fischer-Jung.
“We have noticed that Metso’s blow bars last longer than the competitor ones. In the near future, we will also test Metso’s matrix type blow bars made of steel and ceramic alloy,” says Braun.
