Does My Compound Need A Two-Stage Line?
Start with the material and the target: polymer or blend; recycled content and variability; additives/fillers/fibers; contamination and volatiles; mixing and filtration needs; and throughput and final compound properties.
A Twin-Compound line makes sense when two coordinated extrusion stages add clear process value, for example through staged formulation, intermediate filtration, post-filter additive dosing, separate degassing duties or demanding property modification.
When Does Twin-Compound Fit Better Than A Simpler Line?
Choose Twin-Compound when the representative material and formulation require distinct first- and second-stage duties: controlled first-stage melting/mixing, intermediate removal of defined solid contamination, protected addition of ingredients after filtration, further homogenisation/degassing and final pressure/pelletising.
A simpler route may be better when clean, stable feedstock can reach its target in one stage, when filtration is unnecessary, when all ingredients can be introduced at one suitable point, or when an existing line can be upgraded economically.
Best Suited For:
Define The Property Target Before Selecting Two Stages
Multi-stage processing is not automatically upcycling. First define the current material, its variability and value, the intended application and the measurable property target. Examples may include rheology, tensile/impact properties, stiffness, colour, odour, contamination, moisture/volatiles, filler/fibre dispersion, pellet quality or application performance.
Two stages may create value where filtration must occur between formulation steps, sensitive or non-filterable ingredients must be added after contaminant removal, or separate mixing and degassing duties cannot be achieved reliably in one stage.
How the MAS Twin-Compound Line Works
The complete process combines controlled feeding, first-stage compounding, continuous melt filtration, second-stage compounding and pelletising.
Feed + First Compound
Melt, mix and prepare the recycled input.
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Continuous Filtration
Remove solid contaminants before final formulation.
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Second Compound + Degas
Add sensitive ingredients and remove volatiles.
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Pressure + Pelletise
Build stable pelletising pressure without excess stress.
Flexible Additive and Fibre Incorporation
Additives Before Filtration
Additives and fillers that can safely pass through the filtration stage may be incorporated in the first extruder. This supports early homogenisation and controlled preparation of the recycled melt.
Additives After Filtration
Sensitive, valuable or non-filterable additives can be introduced after contaminants have been removed. This helps preserve additive function and avoids unnecessary material loss through filtration.
Gentle Fibre Feeding
The large feed opening of the second extruder enables rapid introduction of long or irregular fibres, including natural, wood, glass and carbon fibres, with controlled incorporation into the melt.
Key Advantages of the Twin-Compound Concept
High-Quality Regranulation
Two coordinated extrusion stages support demanding recycling compounds, including materials that are difficult to degas or require precise property modification.
Extended Material Addition
Chemicals, fillers and additives can be introduced before or after filtration according to their compatibility, filtration behaviour and process sensitivity.
Strong Homogenisation and Degassing
Conical co-rotating twin-screw extrusion provides intensive mixing, a large melt surface and efficient degassing while maintaining low melt pressure.
Multi-Level Blending
The staged layout supports tailor-made formulations and allows incompatible substances to be introduced separately at the most suitable process point.
Targeted Melt Filtration
Solid contaminants are removed before the second degassing and compounding stage, helping protect final compound quality and downstream processing.
Energy-Efficient Processing
Low melt temperatures, low shear and pressure build-up through the conical extruder design support gentle processing and can eliminate the need for a separate melt pump in suitable applications.
Customisable Line Design
Feeding, additive dosing, filtration, degassing and pelletising can be configured around the recycled material and the required compound properties.
Stable, User-Friendly Operation
The complete system is designed for stable operation, intuitive control and comparatively low maintenance requirements.
Test The Formulation Before Final Line Configuration
Send: representative material and variability; full formulation and ingredient specifications; contamination; moisture/volatiles; current process; required properties; throughput; pelletising/application target; utilities and economic constraints.
Compare: the simplest credible single-stage route, Twin-Compound and relevant modular/retrofit alternatives under agreed conditions.
Record: feeding/dosing; screw and stage configuration; filtration; vacuum; temperatures/speed; ingredient loading; throughput; total-line energy boundary; yield; waste; output tests; deviations; cleaning/changeover and wear observations.
Receive: route recommendation, operating window, ingredient-entry plan, limitations, scale-up assumptions, lifecycle considerations and acceptance criteria.
What Our Customers Say
The conical shape is very advantageous when melting the material, where with little shear and very short dwell time, the material is damaged as little as possible.
Arjan Van Kempen, CEO — Cumapol, Netherlands
We always have to try to buy as good as possible to produce top-quality regranulate. And we do that with the technology we bought from MAS.
Peter Daalder, CEO — Daly Plastics, Netherlands
Fatra was satisfied with the MAS cooperation, the possibility of tests before ordering, MAS innovative solutions and the final production performance achieved.
Ing. Jan Jedovnický, Fatra
Related Technologies
Twin-Screw Extruder
Conical co-rotating twin-screw extrusion for feeding, homogenisation, degassing and pressure build-up.
CDF Melt Filtration
Continuous melt filtration for removing solid contaminants before the second compounding stage.
Re-Compound Line
A single-extruder recycling and compounding concept for filtered regranulate and controlled additive incorporation.
Upgrade Line
A modular concept for upgrading existing recycling systems with additional MAS processing stages.
Technical Test Center
Material evaluation and process validation for MAS 110 project planning.
Send The Formulation, Receive A Line-Concept Comparison
Provide representative material and process data, including polymer/blend, recycled content, contamination, moisture/volatiles, ingredient specifications and loading ranges, fibre form/length, required properties, throughput, target application, utilities, space, changeover needs and economics. MAS will identify data gaps, assess single-stage, Twin-Compound, Re-Compound, iQonicTwin Regrind and retrofit options, define feeding, filtration and degassing requirements and limits, and establish a comparative trial and acceptance plan.
