RAILWASTE - Production of railway sleepers by mixed plastic waste (SUSPRISE Joint Call)

Status

ongoing

Summary

Initial Situation

The overall goal of the development is to prove feasibility of railway crossties ("sleepers") production from an alternative (renewable) raw material. This material will be mixed plastic waste (MPW), in order to increase secondary raw materials use, to improve materials efficiency along with preparation of a business case for railway sleepers from alternative materials.

Sleepers are as a part of the track system used to keep the rails at a given distance, and to transfer mechanical loads to the track bed. Thus the most important properties of sleepers are a defined geometry (typical dimensions are about 2,6 m x 0,3 m x 0,2 m), weather stability, load bearing properties, and low maintenance cost. As of today, sleepers are made from wood, concrete, or to a minor extent from steel.

Objectives

It is proposed to produce railway sleepers from an intelligent combination of post consumer waste materials: Mixed plastic wastes (MPW) along with glass fibre wastes and auxiliary agents will be applied to form a composite product with a thermoplastic polymer matrix, which is reinforced with glass fibers and consists a foamed core. The matrix material is used as a binder, glass reinforcement will add to the mechanical stability and stiffness, and the foaming will reduce materials consumption of the product. The expected weight of the polymer sleepers will be 80 kg. They shall be feasible for automated rain track assembly gear.

Method

In order to prepare large-scale implementation of sleeper production, the project will put its technological focus on the two areas of materials and technology development. In the materials R&D area, a compound from waste, additives, glass fibers is to be developed which can meet the mechanical requirements for sleepers. In the process R&D area, optimum combination of fibre processing, foaming, and shape stability of the profile has to be achieved.

Expected Results

Compared with conventional sleepers, the MPW sleeper is expected to show superior weather resistance (about 40 % longer life span than wooden sleepers), and remarkably lower primary materials consumption (due to the use of waste materials) along with improved acoustic damping properties (over metal and concrete sleepers).

The expected result is the proof of the feasibility of the production of MPW sleepers. Furthermore a generation of samples of this product will be developed.

Project management

Joerg Woidasky
Fraunhofer-Gesellschaft for its
Fraunhofer-Institute for Chemical Technology (ICT)

Project or cooperation partner

• PAV GmbH & Co. KG, Germany
• Next Generation Recyclingmaschinen GmbH

Joerg Woidasky
E-Mail: woi@ict.fhg.de
Internet: www.ict.fraunhofer.de