TRANSFORMING MATERIALS INTO VALUE

Transcription

1 AUTOMOTIVE GLASS RECYCLING Due to the cost implications of producing virgin glass, the recycling of automotive glass (see figure 1) has long made great sense. The disposal costs of this resource are not only expensive but traditional landfill methods are being curtailed due to overburden of landfill sites. Unlike standard glass products, automotive glass is typically made with two or three sheets of glass laminated with sheets of plastic. This makes the recovery of this resource more complicated than standard glass recycling. This has caused the need for recyclers to investigate alternative treatment solutions. As a result of this; BHS-Sonthofen was approached by a blue chip recycling company to investigate different methods of treatment and develop a solution. The goal was to determine if there was an alternative to the standard glass pre-treatment method which although is effective; suffers from a very high wear rates. The solution should crush and de-laminate the glass to achieve clean individual fractions with a low volume of fines. Testing Process BHS selected 2 different pre-treatment machines and 1 secondary treatment machine. 1. A twin rotor shredder, BHS model VR (see figure 2). This twin shaft shredder offers a low speed high torque size reduction solution. The VR shredders breaking action promotes minimized wear impact on the cutting blades. 2. A Rotorshredder Model RS, (see figure 3) a large vertical mill with internal screening offering high throughput with low wear cost. This machine crushes and disaggregates large volumes of materials. This machine can process more material and have a more homogenous crushing result which means the processing time in the secondary machine is reduced. 3. For secondary treatment a Rotor Centrifugal Crusher Model RSMX (see figure 4), which was developed for minerals aggregated industry, is a high speed machine with an internal shelf which allows for autogenous milling. BHS examined 3 scenarios at the test center: small-medium volumes and large volumes. For small volume of material (<2 tph), only pre-treatment with the Twin Shredder (VR) For small volume to medium volume of material (2 10 tph), pre-treatment with the VR then secondary treatment with the RSMX. For large volumes (> 10 tph), BHS selected the RS Rotorshredder for pre-treatment then secondary treatment with the RSMX. The Rotorshredder s greater influence and more homogenous crushing results means that time required in the second step RSMX is reduced.

2 Test Results 1. While the VR shredder successfully size reduces the input materials in preparation for step two its influence on the materials do not start the delamination process. 2. Rotorshredder 2018 for large volume of material starts to have a delaminating effect on crushing input materials as opposed to size reducing them, 3. The output of the two pre-treatment methods was then placed in the RSMX Rotor centrifugal crusher. (see figure 5) The resulting material from the RSMX was successful as the high velocity crushing and delaminating action generated a clean glass cullet free from laminated plastic. The fines produced during the process are used as a talc, deactivating the glue on the plastic laminate preventing any sticky residues. You can clearly see the size variation between the delaminated plastic and glass cullet and the ease at which these can be screened apart resulting in clean recoverable fractions. Conclusion Twin shaft shredder; (VR) has little effect on the infeed material other than to size reduce it to an acceptable grain size for input into the RSMX. Rotorshredder (RS) on the other hand has a much greater effect on the infeed materials generating a much more even feedstock for the RSMX and having a first step delaminating action on the materials. It should however be noted that RS2018 requires large TPH throughput to be both economically viable and effective. Rotorshredder like RSMX needs material to work on material and therefore significant throughput volumes are required. Rotary Centrifugal Crusher (RSMX): We can conclude that pre-treated material fed to the BHS RSMX exit the machine as a clean glass cullet delaminated and free from plastic. (see figures 6 & 7) This valuable recovered glass cullet can be reintroduced to the glass making industry or further size reduced as recovered secondary aggregate or recovered sand. This is also true of many other types of glass treated employing this method. Green glass has of late very successfully been used as recovered sand in many building and drainage projects. The pilot plant at BHS-Sonthofen GmbH (see figure 8) is available for testing of your material. Contact BHS-Sonthofen to arrange your testing. About BHS-Sonthofen BHS-Sonthofen Inc., a wholly-owned subsidiary of BHS-Sonthofen GmbH, offers technical solutions for mixing, crushing, recycling and process filtration. The Recycling division offers a broad range of machine technologies and fully-engineered turnkey systems. BHS shredding, crushing and shearing technologies are used for size reduction in the treatment as well as the

3 pre- and post-shredding of a diverse range of recyclable and waste materials. This includes scrap, shredder residual fractions, slag, incineration bottom ash as well as tires, cables, refusederived fuels and other domestic, commercial and industrial waste. Peter G Schirk Recycling Sales Manager BHS-Sonthofen Inc. Peter.Schirk@bhs-sonthofen.com Website:

4 Figure 1- Automotive Glass Figure 2 - Twin Shaft Shredder (VR)

5 Figure3 - Rotorshredder (RS) Figure 4 - Rotary Centrifugal Crusher

6 Figure 5 - Inside RSMX Figure 6 - Glass Cullet

7 Figure 7 - Size Distribution after RSMX

8 Figure 8 - BHS Pilot Plant