Soil recycling reimagined

The processing of topsoil, excavated soil, or stone-earth mixtures is a typical application for our innovative double trommel screening machines. The goal is to obtain valuable soil or humus with a perfect crumb structure, free from disruptive additives. In this process, turf, building rubble, stones, and roots are reliably removed. The double trommel ensures that clumps are effectively broken up. The fine fraction is usually the target product. Additional value is created by the separately obtained middle fraction, which can be used, for example, as frost protection or backfill material. This significantly reduces disposal costs, as only small residual amounts need to be disposed of.

Typical applications:

• Topsoil processing
• Excavated soil
• Separation of soil and turf
• rock-soil mixture

Construction materials efficiently recycle

Zemmler’s Double trommel technology enables separation into three fractions in just a single operation, making it particularly suitable for recycling building rubble, concrete, and asphalt. The intermediate fraction plays a key role, especially in building rubble recycling: coarse grain is fed directly back into the crushing process, while fine components are extracted separately and recycled for specific purposes. This produces high-quality secondary construction materials such as sand, chippings, and gravel, which can be used in a variety of ways in road construction and landscaping. The result: maximum material utilization, minimal residual waste, and a consistently efficient processing operation.

Typical applications:

Construction Materials

• All types of demolition materials
• Concrete rubble
• Brick rubble
• Asphalt rubble
• Milled material
• Bark

Precise separation of mineral materials in just one screening process

In the field of mineral processing, Zemmler screening machines offer decisive advantages. The double trommel technology enables the recovery of three high-quality fractions in just one screening pass, operating efficiently and economically. Impurities are reliably removed, and materials such as sand and gravel, as well as chippings and gravel, are cleanly recovered. Especially in mineral processing, a particularly fine screening is often required. This can be achieved exceptionally well with double trommel technology: The upstream separation of coarse material in the inner trommel creates a clean cut, enabling precise and efficient fine screening. This also allows for screening down to 2 mm. Another advantage results from the double trommel design: Compared to a single trommel, a significantly larger Screen area is available, leading to higher throughput and overall cleaner material processing.

Typical applications:

• Sand
• Gravel
• Chippings
• Gravel
• Railway ballast
• Lime
• Sand
• Clay
• Steinbruch

Efficient Wood Recycling with our double trommel screening machines

Our double trommel screening machines are among the most popular solutions in the field of wood recycling. They enable the precise screening of waste wood, fresh wood, wood chips, and tree bark, working flexibly and efficiently. A particular focus is on obtaining the intermediate fraction as the target product. In many applications, this represents the actual value fraction. The coarse material is fed back to the shredder, while overly fine components are reliably separated. These include mineral components that can cause slagging in the combustion process, as well as very fine sawdust that can cause unnecessary ash formation and disrupt the combustion process. The separated fine sawdust is often further processed, for example pressed and used for new products. This creates an efficient and stable material cycle.

Typical applications:

• Sawmills
• Combined heat and power plants
• Forestry
• Firewood
• Refinement of wood chips (for decorative purposes)
• Bark

High-quality biomass processing for maximum value creation

In compost processing, targeted screening ensures efficient utilization of all material fractions. The fine fraction, for example 0 to 10 mm, is considered a high-quality target product and can be reused in various ways depending on its quality. The middle fraction, approximately 10 to 50 mm, is returned to the rotting process so that valuable organic components can continue to decompose and then be reprocessed. Coarse components from 50 mm upwards are reliably separated and, depending on the material properties, shredded, disposed of, or also returned to the rotting process. This structured separation improves the quality of the end product and the overall process flows. Existing biomass is utilized more efficiently, resources are conserved, and the processing becomes more sustainable.

Typical applications:

• Green waste
• compost
• Processing for biogas plants and thermal power stations

Metal Recycling maximize value

Zemmler double trommel screening machines enable particularly precise and economical processing in metal recycling. In a single screening pass, several fractions are separated, allowing even fine metal particles to be reliably captured and recycled. The decisive advantage lies in the double trommel technology: The separate separation of coarse material in the inner trommel creates a very clean separation cut. This significantly stabilizes and refines the separate fine screening – even screenings down to 2 mm are reliably achievable. This combination of separation and large Screen area ensures high accuracy combined with high throughput, making the systems particularly efficient in metal recycling.

Typical applications:

• Aluminum scrap
• Iron and steel scrap
• Copper and brass scrap
• Electronic scrap / Cable scrap
• Light metals in the automotive or electronics industry
• Powder metals / Metal dust

Waste Recycling – Recovery of Substitute Fuels

In the recycling of waste for the recovery of substitute fuels, the focus is on utilizing waste as a valuable raw material that can be further processed to create economic and ecological value. At the same time, this process contributes significantly to resource conservation and sustainability. A central aspect is the targeted recovery of the intermediate fraction as the target product. This defined fraction represents the actual usable fuel. The coarse material is returned to the crusher or shredder to be reprocessed and achieve an optimal grain size. Fine components, on the other hand, must be consistently separated. These often consist of mineral components that can lead to slagging in the combustion process, as well as very fine particles that cause unnecessarily high ash formation and negatively affect the combustion process. For even more efficient processing, the use of ripping blades can be beneficial to reliably open garbage bags during the screening process and improve material release. Additionally, magnetic separators can be installed on all discharge belts to separately recover metals.

Typical applications:

• Waste
• Glass
• Rubbish
• Plastics
• Substitute fuels
• Separation of films

Riding Arena Surface Preparation for perfect ground quality

Clean ground for healthy hooves. Our screening technology delivers clear results. The Zemmler MULTI SCREEN® screening machine demonstrates its versatility particularly in riding arena and fleece preparation. In a practical test, it was used with a mesh size of 10 mm to process heavily contaminated material from a horse walker. The initial material consisted of a challenging mixture of fleece shreds, horse manure, sand, and other contaminants, some of which were compacted into large, solid clods. Despite this difficult initial situation, the process yields reprocessed, reusable fleece material and a significantly cleaner end product. Even heavily caked and previously problematic layers are reliably broken up and separated, allowing clean material to be reinstalled and residual waste to be disposed of cost-effectively.

Typical applications:

• Preparation of riding hall surfaces
• Screening of riding arena sand
• Recycling of riding arena mixtures
• Separation of sand and fleece fibers
• Removal of foreign objects

Special Materials flexible processing

Zemmler double trommel screening machines are suitable not only for soil, waste, or scrap recycling as well as mineral and biomass processing, but also for special and demanding materials. The decisive advantage lies in the separation of three fractions in just one screening pass—one more than conventional systems. Thanks to the interchangeable wire screen linings, the mesh sizes can be flexibly adjusted, enabling quick material changes and precise processing at any time. This creates high flexibility for a wide range of applications and material requirements.

Typical applications:

• Salt
• Coal
• FGD plaster
• Sandbag Processing
• Shooting Sand Processing