Benninghoven performance “down under”

Benninghoven TBA 4000 transportable asphalt mixing plant with environmentally friendly technology in Yatala, Australia

Commissioning of a TBA 4000 transportable asphalt mixing plant with environmentally friendly technology in Yatala, Australia

Yatala | Queensland, Australia

Benninghoven’s TBA-type transportable asphalt mixing plants are a popular choice around the world. Like in Yatala (Queensland), for example, where, the COLAS Australia Group has just commissioned a TBA 4000. With this investment, the road-building company aims to produce asphaltic mixtures of a consistently high quality and quantity while also achieving recycling rates of up to 40% and while maximizing its energy-saving potential. In addition, COLAS has integrated a foam bitumen module for the production of temperature-reduced asphalts.

By using Benninghoven’s technology, the company can be sure to comply with all of Australia’s national specifications and their customer requirements. Many of these focus on temperature-reduced asphalt – also known as warm mix or low-temperature asphalt. All in all, the TBA in this configuration shows off the all-rounder features that are popular with owners and operators alike worldwide.

Highlights of the TBA 4000 in Yatala, Australia

320 t/h

is the maximum mixing capacity of the TBA 4000

Strong plant performance and mature recycling technology

The COLAS Australia Group is a leading provider of sustainable solutions for road building and road maintenance. As part of its strategy to remain at the forefront of its sector, the Group was looking for an asphalt mixing plant provider able to fulfill multiple requirements. “We picked the TBA because we’d already had a great experience with three other mixing plants from Benninghoven in the past. And of course we were also impressed by the high level of productivity this plant offers, plus the chance to reuse our reclaimed asphalt,” reports Thierry Madelon, CEO COLAS Australia Group. “The TBA is also a perfect match for the rest of our requirements spec.”

The multivariable cold feed system is responsible for ensuring the recycling rate of up to 40%. The system batch-feeds the old, shredded asphalt from renovation projects directly into the 4 t mixer in the TBA 4000. This avoids the kinds of vapor clouds that suddenly form when large quantities of cold and hot material are forced together. This protects both the mixer and the other plant components.

Sustainable and energy-efficient: the TBA 4000 at COLAS.

Multivariable feed system

Cold recycling of up to 40% RAP: highlights of the multivariable feed system

Cold recycling feed system with gentle, batched feeding into the mixer
This prevents shocks from rapidly expanding hot water vapor
Protects materials and components
Patented system (European patent EP 2554746B1)
High-precision weighing technology for exact dosing
Maximizes feed rates for cold recycling
Dosing option for any non-tacky bulk materials – e.g. Trinidad asphalt, rubber granulate, etc.

Cold recycling of up to 40% RAP: Figure: multivariable feed system

RAP feed box

The second integrated recycling feed system doses the reclaimed asphalt (RAP) right into the dryer drum.

10 cold feed hoppers and four bitumen tanks for many different recipes

COLAS was looking in particular for a plant that offered great flexibility for asphalt recipes. “Our client has stringent quality requirements for their asphaltic mixture. Based on where the asphalt will be laid, different proportions of RAP are allowed to be added. Our client also requires different types of bitumen, depending on the specific recipe,” comments Cameron Nisbett, CEO COLAS Queensland. To meet these needs, the TBA 4000 at COLAS in Yatala offers a number of plant options. As one example, the plant has eight cold feed hoppers for virgin mineral in various particle sizes. The recycled material is also provided in various particle sizes by two other cold feed hoppers. When it comes to bitumen, COLAS has a choice of four types, allowing the use of specialized recipes. The bitumen tanks needed for this are very energy efficient – something Benninghoven has achieved by using electric heaters combined with insulation that is no less than 300 mm thick.

“Together with the Recipe Generator, this plant specification lets us meet any set of requirements that our clients are likely to specify,” explains Thierry Dulac, Plant and Fleet Manager at COLAS Australia Group. The Recipe Generator is just one of the many highlights in Benninghoven’s user-friendly BLS 3000 control system. The mixing supervisor simply picks a recipe stored in the system and all of the parameters across the plant are set automatically for the asphaltic mixture to be produced.

Benninghoven’s Recipe Generator is also a great help when it comes to feeding in recycled material. This software option in the Benninghoven BLS 3000 control unit lets operators change the recycling rate on the fly. If a job has been started with a virgin mineral proportion at 100%, for example, the mixing supervisor can use a sliding control to then add RAP at any time. This virgin mineral proportion, along with all the other ingredients in the recipe like bitumen, filler, etc. are adjusted automatically while maintaining the asphaltic mixture’s grading curve – without stopping production or changing the recipe, and while keeping temperature and quality constant.

A total of ten cold feed hoppers (bottom of photo) and four bitumen tanks: the TBA 4000 at COLAS can handle many different types of asphalt recipes.

A total of ten cold feed hoppers and four bitumen tanks: the TBA 4000 at COLAS can handle many different types of asphalt recipes.

Foam bitumen module improves energy efficiency

Apart from the recycling technology, a foam bitumen module also helps to make operations more energy-efficient. This module gives the TBA 4000 the capability to produce warm mix asphalts. Compared to conventional hot mix asphalt, this low-temperature asphalt is processed and laid at a temperature that is 20–40 °C lower. When using foam bitumen as a binder, the production process for asphaltic mixtures improves overall energy use while also reducing production-related emissions. With a daily output of 2,000 t, this adds up to savings of 1,800 l of heating oil (or other energy source) plus a 6 t reduction in CO₂ emissions.

When manufacturing low-temperature asphalts, a temporary reduction in bitumen viscosity is needed, which can be achieved by the addition of water. By mixing hot bitumen with water in the Benninghoven foam bitumen module, the bitumen is foamed up to several times its original volume. Thanks to its large surface area, this technology simultaneously improves the wettability of the stone materials.

Injection nozzle bars are used to feed the foam bitumen into the mixer directly. Apart from the foaming of the bitumen, the production process is otherwise largely unchanged. All of which means that foam bitumen is not only better for the environment but is also cost-effective for plant owners.

* Deutscher Asphaltverband e.V., Asphalt Guideline, Reduced-Temperature Asphalts

“The foam bitumen module takes us another step toward our goal of maximum sustainability. Lower production temperatures also mean less energy used – which naturally also cuts our CO₂ emissions.”

Thierry Dulac, Plant and Fleet Manager
COLAS Australia Group

Benninghoven’s foam bitumen module: this technology is integrated into the weighing/mixing section to facilitate the production of warm mix asphalts. When injected into the mixer, the foamed binder binds optimally to the recycled material thanks to its large-pored surface texture, which ultimately results in a hard-wearing asphalt.

Proven technology from the foam bitumen pioneer – the Wirtgen Group

An internationally established binder, foam bitumen is starting to carve out a large share of the market for road construction and maintenance, and is an increasingly interesting option for road authorities and construction firms.

Process advantages:

Environmentally-friendly due to major energy savings
Resource-friendly due to reduced fuel usage
Material-friendly due to less bitumen aging and lower rates of plant wear
Economical due to lower variable costs

More options with the Benninghoven burner

The EVO JET also plays a part in plant efficiency. This burner from Benninghoven can be run on no fewer than four different fuels. Operators can switch between heating oil, natural gas, liquefied gas, coal dust, and biomass-to-liquid (BtL) fuels at the touch of a button. This makes plant owners less dependent on commodity markets and means the burner can always be run on the cheapest fuel. An advanced frequency control ensures maximum efficiency during operation.

With their chosen plant configuration for the TBA 4000, the COLAS Australia Group can face the future with confidence. And the company’s clients in the State of Queensland can also look forward to first-class asphaltic mixtures produced with the green technology offered by a TBA 4000.