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The Effect of Construction and Demolition Waste Plastic Fractions on Wood-Polymer Composite Properties
Published on: June 7, 2020
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Sorting efficiency in mechanical sorting of construction and demolition waste
Marko Hyvärinen1, Mikko Ronkanen2, Timo Kärki1
1Fiber Composite Laboratory, Lappeenranta University of Technology, Finland.
Summary
Recycling construction and demolition waste requires efficient sorting technology. This study shows mechanical sorting equipment reliably produces nine fractions, balancing cost and purity for effective material recovery.
Area of Science:
- Environmental Science
- Materials Science
- Engineering
Background:
- Increasingly stringent regulations necessitate improved construction and demolition waste (CDW) recycling.
- Effective CDW recycling relies on advanced sorting technologies for material recovery.
- CDW comprises diverse recyclable materials like metals, plastics, and wood.
Purpose of the Study:
- To evaluate the mechanical sorting efficiency of CDW using commercial roller screening and air separation equipment.
- To assess the impact of material characteristics on sorting system performance.
- To determine cost-effective sorting strategies based on purity and profitability.
Main Methods:
- Utilizing pre-sorted and crushed test material for mechanical sorting trials.
- Employing sieve analysis to establish particle size distribution before sorting.
- Operating a commercial sorting system with roller screening and air separation units.
Main Results:
- The mechanical sorting equipment reliably produced nine distinct fractions from mixed CDW.
- Particle size distribution, determined by sieve analysis, influenced sorting outcomes.
- The quality criteria of CDW presented challenges to consistent sorting system operation.
Conclusions:
- The tested mechanical sorting equipment demonstrates reliability in fractionating CDW.
- Achieving cost-efficient sorting requires balancing the desired purity level with utilization profitability.
- A compromise between sorting costs and fraction purity is typically necessary for practical CDW recycling.
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