How to Recycle Styrofoam?
Recycling Styrofoam is important to reduce environmental pollution, but it can be a bit challenging because it is not accepted in curbside recycling programs. However, there are still ways to recycle Styrofoam, and here is a step-by-step guide on how it is done.
1. Collecting Used Styrofoam
The first step in recycling Styrofoam is to collect the used material. This can be done by individuals, businesses, or through municipal recycling programs.
Styrofoam will still be marked with the recycling symbol even though you typically cannot put it in your recycling bin. A number that identifies the kind of plastic the recycling symbol is composed of can be found inside the symbol. To find out what kinds of plastic your local recycling business accepts, inquire with them. The majority of recycling services require:
- Plastic #1: Polyethylene terephthalate is the plastic used in drink bottles, food containers, and detergent containers.
- Plastic #2: High-density polyethylene makes up containers like milk jugs, water jugs, and shampoo bottles.
- Plastic #5: Polypropylene is found in items like yogurt and pudding cups. Not every recycling location will accept plastic #5.
2. Cleaning and Shredding
Styrofoam is separated from other materials like paper, plastic, or food scraps. This is important as contamination can make recycling difficult. Then, any stickers or labels that may be present on the Styrofoam are removed. It is then inspected for any food residue or dirt. Styrofoam needs to be cleaned before shredding if it is dirty. It is wiped down with a damp cloth or washed in warm, soapy water. It is then dried before shredding. A specialized Styrofoam shredder is used to shred the Styrofoam into small pieces. Lastly, the shredded Styrofoam is collected in a plastic bag or container. The shredded Styrofoam or beads can now be melted down and transformed into pellets for reuse.
3. Melting and Transforming Paste into Pellets
The beads are mixed with a special solvent, usually a hydrocarbon, to turn them into a thick paste. The solvent used is usually a hydrocarbon mixture that dissolves the EPS foam. The paste is then heated in a reactor vessel to a temperature of around 180-220°C (356-428°F), causing it to melt. This process is carried out under pressure to prevent the solvent from boiling and evaporating, which can cause the foam to break down. Once the paste has melted, it is extruded into long strands using an extrusion machine. These strands are then cooled and cut into small, cylindrical pellets. The pellets are then dried to remove any residual moisture and are packaged for distribution to manufacturers who can use them in various applications.
4. Transporting the Pellets to Manufacturers
The final step is to transport the Styrofoam pellets to manufacturers who can use them to create new products. These pellets can be used to create a variety of items such as picture frames, crown molding, and even surfboards.