How to recycle LDPE HDPE LLDPE Scraps Onsite

Recycling is a crucial part of sustainable waste management, and polyethylene (PE) is one of the most commonly used plastics in the world. In this blog post, we’ll look at how to recycle LDPE, HDPE, and LLDPE scraps onsite.

Polyethylene (PE) Classification

Polyethylene is a thermoplastic polymer that is classified into three categories: Low-density polyethylene (LDPE), high-density polyethylene (HDPE), and linear low-density polyethylene (LLDPE). Each type has different physical and chemical properties, making them suitable for various applications.

Basic Information of LDPE

LDPE is a type of polyethylene with a density of less than 0.94 g/cm3. It is a flexible and transparent plastic that is often used in packaging films, grocery bags, and containers. LDPE is easy to process and has excellent resistance to water, acids, and bases.

Advantages of LDPE

• Flexibility: LDPE is a flexible plastic that can be easily shaped into various forms.
• Transparency: LDPE is transparent, making it ideal for packaging applications.
• Water resistance: LDPE is highly resistant to water and moisture, making it suitable for outdoor applications.
• Chemical resistance: LDPE has excellent resistance to acids and bases, making it useful in the chemical industry.

Disadvantages of LDPE

• Low melting point: LDPE has a low melting point, making it unsuitable for high-temperature applications.
• Vulnerable to UV rays: LDPE is susceptible to degradation from UV rays, which limits its outdoor use.
• Low tensile strength: LDPE has low tensile strength, making it unsuitable for structural applications.

Common Applications of LDPE

LDPE is used in various applications, including:

• Packaging films and bags
• Squeeze bottles
• Toys and playground equipment
• Agricultural films
• Corrugated pipes

Basic Information of HDPE

HDPE is a type of polyethylene with a density of more than 0.94 g/cm3. It is a stiff and strong plastic that is often used in pipes, containers, and toys. HDPE is easy to process and has excellent chemical resistance.

Advantages of HDPE

• Strength: HDPE is a strong plastic that can withstand high pressures and loads.
• Chemical resistance: HDPE has excellent resistance to chemicals, making it useful in the chemical industry.
• Weather resistance: HDPE is resistant to weathering and UV rays, making it suitable for outdoor applications.
• Recyclable: HDPE is easily recyclable, making it an environmentally friendly plastic.

Disadvantages of HDPE

• Low thermal resistance: HDPE has a low thermal resistance, making it unsuitable for high-temperature applications.
• Difficult to bond: HDPE is difficult to bond with other materials, making it challenging to use in multi-material products.

Common Applications of HDPE

HDPE is used in various applications, including:

• Water and gas pipes
• Bottles and containers
• Toys and playground equipment
• Chemical tanks
• Recycling bins

Basic Information of LLDPE

LLDPE is a type of polyethylene that is a blend of LDPE and HDPE. It has a density between 0.915 and 0.925 g/cm3, making it a more flexible and thinner plastic than HDPE. LLDPE is often used in packaging films, stretch wrap, and bags.

Advantages of LLDPE

• Flexibility: LLDPE is a flexible plastic that can be easily shaped into various forms.
• Strength: LDPE is a strong plastic that can withstand punctures and tears.

• Good cling: LLDPE has good cling properties, making it useful for stretch wrap applications.
• Resistance to punctures and tears: LLDPE has good resistance to punctures and tears, making it useful for packaging applications.

Disadvantages of LLDPE

• Lower chemical resistance: LLDPE has lower chemical resistance than HDPE, making it less suitable for some chemical applications.
• Limited thermal stability: LLDPE has limited thermal stability, making it unsuitable for high-temperature applications.

Common Applications of LLDPE

LLDPE is used in various applications, including:

• Stretch wrap
• Bags and packaging films
• Agricultural films
• Cable insulation

Comparison of LDPE, HDPE, and LLDPE

Here’s a comparison of the three types of polyethylene:

Property	LDPE	HDPE	LLDPE
Density (g/cm3)	<0.94	>0.94	0.915-0.925
Flexibility	Highly flexible	Stiff	Flexible
Tensile strength	Low	High	Moderate
Chemical resistance	Good	Excellent	Lower than HDPE
Weather resistance	Vulnerable to UV rays	Resistant to weathering and UV rays	Moderate resistance to weathering and UV rays
Recyclability	Easily recyclable	Easily recyclable	Easily recyclable

How to Recycle LDPE, HDPE, and LLDPE Scraps Onsite

The traditional way(not eco-friendly)

Recycling LDPE, HDPE, and LLDPE scraps onsite is a straightforward process that involves the following steps:

1. Collect the scraps: Collect all the LDPE, HDPE, and LLDPE scraps generated onsite and sort them by type.
2. Wash the scraps: Wash the scraps to remove any dirt, dust, or other contaminants.
3. Shred the scraps: Shred the clean scraps into small pieces using a shredder.
4. Melt the scraps: Melt the shredded scraps in a melting machine or extruder.
5. Form the recycled material: Form the melted material into a new product using a molding machine or extruder.

The NEW way(Eco-friendly way to recycle onsite)

With a new-tech plastic granulator, Recycling polyethylene scraps onsite become an eco-friendly and cost-effective way to reduce waste and save resources for plastic film products manufacturers. The machine used is called new-tech plastic granulator, not like a traditional plastic granulator production lines, the new-tech plastic granulator adopts low-temp granualting technology, help to keep the original properties of the plastic materials, the process needs no water to cool, no aggressive high-temperature damage, no waste generated, no water pollution made. The new-tech plastic granualtor simple the recycling process as below:

1. Put the scraps into the feeder;
2. The screw will crush and half-melt the pieces and extrude them into short plastic strands;
3. Just as the strands come out, the spinning blade will cut them into uniform pellets;
4. The pellets will be air-cooled and blowed to the conveyor pipe to further cooling down.

 

Comparison the traditional plastic granulator and the new-tech plastic granulator

Aspect	Traditional Granulator	New-Tech Granulator
Production Line Size	Large	Compact
Melting Technology	High-Temperature	Low-Temperature
Method of Melting	Direct Heat	Friction Heat
Impact on Plastic Properties	Changes properties of plastic	Maintains properties of plastic
Quality of Pellets	Lower quality pellets	Higher quality pellets
Reusability of Pellets	Fewer reusable pellets	More reusable pellets
Ease of Use	Requires experienced worker	Simple to operate with only a few buttons to click
Application Scenery	Suitable for general recycling centers that buy all kinds of plastic materials	Suitable for specific plastic product manufacturers to recycle scraps and unqualified products onsite.
Requirements of Recycled Materials	Materials need to be sorted, washed, and shredded by heavy labor, which is time-consuming and costly.	Materials do not need to be sorted or washed, and potential impurities can be filtered out by the mechanism, resulting in a lower cost and less time-consuming process.

In summary, the traditional granulator requires recycled materials to be sorted, washed, and shredded, which is a time-consuming and labor-intensive process. In contrast, the new-tech granulator does not require any sorting or washing of recycled materials, and potential impurities can be filtered out by the mechanism. This results in a more efficient and cost-effective process for recycling plastic materials.

By recycling LDPE, HDPE, and LLDPE scraps in the new-tech way, you can not only save a big investment on traditional plastic granulator lines, but make the recycling process efficient and easy.

Conclusion

Polyethylene is a versatile plastic that is used in various applications worldwide. LDPE, HDPE, and LLDPE are three types of polyethylene with different properties and applications. Using a new-tech way of recycling polyethylene scraps onsite is an effective way to reduce waste and conserve resources.