WASTE REFINING TO VALUABLE INTERMEDIATESDifferent micronization methods are used in the processing of waste materials:

• Impact mill• Vibratory disc mill• Ultrafine grinder• Microfluidizer

Waste fractions are analyzed for their potential as composite reinforcement or filler

• Waste fraction selection criteria: High aspect ratio (l/d–ratio) High fiber content Density (high/low)

• Most suitable waste fractions are processed into composites with

1) Thermoplastics such as PP2) Thermosets such as PU

• Composite manufacturing methods

• Twin-screw extrusion• Hot casting

INTRODUCTIONSustainable use of renewable natural resources and the recycling and re-use of waste materials targeting to highermaterial efficiency are the key factors in the MiKOMP (Mikronisoitujen jätekuitujakeiden hyödyntäminenkomposiittirakenteissa) project. In this research project the focus is on the recycling and re-use of fiber containingwaste materials by using them as low cost reinforcements or fillers in polymer matrix composites. The aim is to turnthe locally produced fiber waste materials into valuable components for composite materials by utilization of suitablemicronization, separation and classification methods.

Hietala, M., Upola, H., Karinkanta, P., Ojala, J., Piltonen, P., Haapala, A. & Niinimäki, J.Fibre and Particle Engineering, University of Oulu, Finland

Micronization of waste fractions and their utilization in composite materials

RECOVERED WASTE MATERIALSVarious fiber containing wastes are studied in the project:

• Waste board and paper• MDF sawing dust• Mineral wool waste• Glass fiber composite wastes• Fiber rejects from paper making• Carbon fiber composite waste

Dry

Wet

Abrasion testing

Mechanical testing

Composite product

PROJECT OUTCOME• Composite properties are compared to composites with virgin materials as reinforcements/fillers• The feasibility and performance of waste fiber materials in composites is evaluated • Promising synergies and material applications for local industries are identified