Sustainable recycling close to the construction site.

The Wirtgen KMA 240(i) mobile cold recycling mixing plant offers an extended range of capabilities

The Wirtgen Group offers a variety of solutions for the recycling and re-use of road construction materials such as milled material produced during the rehabilitation of asphalt roads. One of these solutions is the KMA 240(i) mobile cold recycling mixing plant. This high-performance plant from Wirtgen is an ideal choice for the environmentally compatible and cost-effective production of mix close to construction sites. It enables contractors to convert up to 240 tons of old material into new, high-quality mix – every hour.

Optimum material flow in a perfectly coordinated system – discover more about the Wirtgen KMA 240(i) mobile cold recycling mixing plant – and what it can do for you.

Production of materials ranging from bitumen-bound to cement-treated base layer mixes.

Mounted on a flatbed semitrailer, and equipped with its own engine unit, the new KMA 240(i) mobile cold recycling mixing plant is set down close to the construction site and is ready to go almost right away. This mobile configuration enables rapid redeployment of the plant to any other location. Adding to the proven advantages of its predecessor, the KMA 220(i), the engineers at Wirtgen have upgraded both the performance and the precision of the new plant. The outstanding features of the new KMA 240(i) are higher mixing performance and an innovative cement metering system with automatic self-calibration system controlled by static weighing. Fresh bitumen is added to the mix in the form of bitumen emulsion or foamed bitumen.

Thanks to its powerful six-cylinder diesel engine, the new, high-performance Wirtgen cold recycling mixing plant can process 240 tons of material per hour. On a full tank, the engine provides sufficient power for up to two days of exceptionally cost-efficient production of recycled mix from a wide range of non-cohesive base materials – generally sourced from Wirtgen cold milling machines. The low engine emissions also allow operation of the plant in urban areas. Thanks to the highly effective soundproofing of the engine housing, plant operatives and local residents will particularly welcome the significant reduction of noise emissions.

Tolles Produkt

The hourly processing of 240 tons of material is equivalent to 20 tons of cold recycling mix every 5 minutes

Environmentally friendly, cost-effective and versatile – cold recycling with the KMA 240(i)

In the case of cold in-plant recycling, a mobile cold recycling mixing plant (KMA) is set up at a location close to the construction site. This saves time, reduces material haulage requirements and minimises environmental impact, making it possible to achieve the following benefits – up to 60% lower CO₂ emissions through cold processing, up to 50% shorter construction times and up to 50% lower construction costs.

The KMA 240(i) mobile cold recycling mixing plant produces mixes for immediate paving and is suitable for the production of various types of bound base layers. In addition to mix for cement-treated base layers (CTB) and roller-compacted concrete (RCC), the plant can also be used to produce bitumen-bound base layers by the addition of bitumen in the form of bitumen emulsion or foamed bitumen. The different mixes can be used for a wide range of applications, including the construction of motorways, roads and paths and car parks.

The new roads and industrial areas built in this way stand out for their high load-bearing capacity, resistance to deformation and long service life. Wirtgen cold recycling technology therefore stands not only for maximum sustainability and the conservation of natural resources, but also offers significant potentials for cutting overall costs.

The main control panel enables the operator to access real-time information about the material flow, the machine status and the entire production process at any time.

The advantages in figures
Recycling of existing materials
as much as 100%
Reduction of material for disposal
as much as 100%
Reduction of construction material haulage
as much as 90%
Reduction of required resources
as much as 90%
Reduction of binding agents
as much as 50%

The cutting-edge process technology of the KMA 240(i) ensures faster mix production

Thanks to its microprocessor control system, the KMA 240(i) works with outstanding precision. The plant is supplied with binding agents such as hot bitumen, bitumen emulsion, and cement from storage silos or road tankers. The precise metering of the base materials and binding agents in proportions determined beforehand in a road construction laboratory is monitored by a tried-and tested microprocessor control system. In the best-case scenario, the KMA 240(i) continuously stockpiles the new, homogeneous mix of construction materials or loads it directly onto trucks.

The paving process with a cement-treated base layer (CTB)

5. Paving
1. Milling + stabilisation
2. Transport / unloading
3. KMA 240(i)
4. Transport from the plant to the construction site

Case study: New CTB at Paderborn-Lippstadt Airport

During the rehabilitation of the apron and the refuelling and de-icing area of Paderborn-Lippstadt Airport, the requirements included not only a high mixing capacity, but also an increase of the compressive strength of the new cement-treated base layer (CTB). On one of its first proof-of-concept outings, the KMA 240(i) took only seven days to produce the required quantity of ready-to-pave mix from 5,500 tons of construction materials.

Prior to this, the lead contractor, Oevermann, had already milled off 15,000 m² of tarred surface from the project site with a Wirtgen W 220(i) cold milling machine and had stockpiled the material removed in an adjacent car park, together with the crushed limestone 0/5 that was to be used as an additive. The two construction materials were loaded into the hopper of the KMA by a wheel loader in the proportions 80% milled material to 20% crushed limestone, where they were processed together with cement as a binding agent and water in the plant’s twin-shaft pugmill to produce a high-quality mix.

Tolles Produkt

Potential feed rate of up to 10% binding agent

In general, the unconfined compressive strength of such mixes is 5–7 MPa. In this case, however, the CTB was required to meet the higher specification and achieve an unconfined compressive strength of 12.5–15 MPa. The operator of the KMA 240(i) therefore decided to increase the proportion of cement in the material mix of milled material and limestone to 10% instead of the usual 5–6%. The ability to precisely adjust the feed rate of binding agents is one of the advantages of the more advanced features of the KMA 240(i) that extend its range of applications.

Thanks to the daily production of around 800 tons of cement mix, the downstream paving equipment was also able to operate without interruption. After a grader had evenly distributed the material across the individual sections, a team of two Hamm 3412 compactors ensured optimal compaction of the new CTB.