Why Should Plastic Be Cleaned?
Many people assume that once waste plastic is shredded, it can be directly granulated; however, it is not quite that simple. Cleaning plays a particularly critical role in the recycling process—so much so that it directly determines the quality of the resulting granules.
If the material is not thoroughly cleaned, the following issues are highly likely to arise during subsequent stages:
- Granules turning black
- Pungent, acrid odors
- Machine clogging
- Melt instability
- Poor finished product quality
Therefore, for any legitimate recycling operation, cleaning is an essentially indispensable step in the process.
Where Is the “Dirt” in Waste Plastic?
Much of the recovered plastic carries various surface impurities, such as:
- Soil
- Oil stains
- Beverage residues
- Adhesives
- Labels
- Metal shavings
- Sand
- Dust
This is particularly true for household plastic waste, where the level of contamination is often far more severe than one might imagine.
Why Is Cleaning So Important?
Improving the Quality of Recycled Plastic
The more thoroughly the material is washed, the higher the purity of the resulting plastic pellets typically is.
High-quality pellets:
- Exhibit greater color stability
- Have a fainter odor
- Offer superior melting performance
- Are easier to sell
Reducing Equipment Wear
Sand and metal contaminants within the plastic can cause significant wear and tear on the equipment.
This applies particularly to:
- Granulator screws
- Blades
- Die heads
If contaminated materials are processed over an extended period, the service life of the equipment will be significantly reduced.
Preventing Problems During Pelletizing
When dirty plastic undergoes high-temperature granulation, it is prone to the following issues:
- Smoking
- Screen clogging
- Carbonization
- Strand breakage
In severe cases, it may even lead to a complete shutdown.
Raising the Value of Recycled Plastic
Even when dealing with the same type of recycled plastic pellets, the price gap between clean and unclean batches can be substantial.
This is because manufacturers prefer materials that feature:
- Minimal impurities
- Low moisture content
- Faint odor
Plastic cleaning not only impacts the quality of recycled granules but also affects the operational efficiency of the entire recycling line.
Gomine offers a wide range of plastic cleaning and recycling equipment—including PET bottle washing lines—designed to help enhance plastic recycling efficiency and improve the quality of finished products.
