How Recycling Works

Summary

This video explores the fascinating world of recycling, breaking down the complex processes that transform waste into reusable materials. It covers the different types of Material Recovery Facilities (MRFs), including Single Stream and Dual Stream systems, and the sorting methods used to separate paper, steel, glass, aluminium, and plastic. Viewers learn about the recycling of common materials, from the transformation of paper into pulp to the separation of plastics by type. The video highlights how different materials, like glass and aluminium, are recycled into new products, emphasizing the importance of proper waste sorting for environmental sustainability.

Takeaways

• 😀 Recycling is the process of collecting and breaking down waste materials to create new products.
• 😀 Different materials require different recycling processes; for example, paper is broken down into cellulose fibers, while glass is crushed into cullet.
• 😀 Material Recovery Facilities (MRFs) are specialized plants that sort recyclables, and they can be either 'Single Stream' or 'Dual Stream' recycling facilities.
• 😀 In Dual Stream Recycling, waste is separated at the curbside into 'Mixed Paper' and 'Everything Else', whereas Single Stream combines everything into one bin for sorting later.
• 😀 Some items, like computers, batteries, and light bulbs, cannot be recycled at MRFs and need to be handled separately.
• 😀 MRFs primarily sort five materials: paper, steel, glass, aluminum, and plastic.
• 😀 Paper recycling involves compacting, baling, pulping, and de-inking to remove contaminants like ink and plastic before turning it into new products.
• 😀 Steel is recycled by being crushed, baled, melted, and then mixed with new steel to create new products like cans and cars.
• 😀 Glass is sorted by color (clear, brown, and green) to prevent degradation of contents like beer, which is sensitive to light exposure.
• 😀 Aluminum is separated from plastic using a high-powered magnetic field created by an 'Eddy Current Separator', and then recycled into new products like cans or foil.
• 😀 Plastic recycling is complex because different plastics have varying molecular structures, making some easier to recycle than others. Plastics are separated by type to preserve their properties.

Q & A

What is recycling and why is it important?

Recycling is the process of collecting waste materials, breaking them down into basic components, and reusing them to create new products. It is important because it reduces waste, conserves natural resources, and helps protect the environment.

What are Material Recovery Facilities (MRFs) and how do they work?

Material Recovery Facilities (MRFs) are specialized plants where recyclables are sorted, cleaned, and processed. They use various techniques such as rotary screen separators, magnets, and air classifiers to separate materials like paper, glass, and plastics, allowing them to be recycled effectively.

What is the difference between Single Stream and Dual Stream Recycling?

In Dual Stream Recycling, materials are separated into two categories—mixed paper and everything else—before being sorted. In Single Stream Recycling, all materials are collected in one bin and sorted later by both people and machines. Single Stream Recycling is growing in popularity despite being used by less than half of MRFs.

How is paper recycled in a Material Recovery Facility?

Paper recycling begins by separating it from other materials using rotary screen separators. The paper is then compacted, sent to a mill, and put into a hot water bath to break it down into pulp. The pulp is cleaned by filtering out ink and dirt before being de-inked with air bubbles and surfactants, and finally formed into new paper products.

What happens to steel in a recycling facility?

Steel is separated from other materials using a powerful magnet. Once separated, it is crushed, baled, and sent to foundries where it is melted down. The recycled steel is then mixed with new steel to create new products like cans, cars, and beams.

How is glass processed in recycling?

Glass is separated from other materials using air classifiers and is then crushed into small pieces called cullet. The cullet is sorted by color—clear, brown, or green—because these colors cannot be removed during recycling. The cullet is then melted down to create new glass products.

Why is glass separated by color during recycling?

Glass is separated by color because different colors are made with different ingredients, which affect the properties of the glass. Clear glass, for example, is made from silica, while brown and green glass contain additional materials to block UV rays, making it necessary to recycle them separately.

What is an Eddy Current Separator and how does it work?

An Eddy Current Separator is used to separate aluminum from plastic in recycling. It creates a powerful magnetic field that induces a current in the aluminum, causing it to be repelled onto a separate conveyor belt, while plastic continues along the main belt.

How is plastic separated and recycled in MRFs?

Plastics are separated by type using infrared sensors that identify the specific polymer based on the light it reflects. Once identified, air blasts separate the plastics into different groups. Plastics like PET can be melted down and reused, while others like PVC require specialized processing.

Why is it difficult to recycle Styrofoam (expanded polystyrene)?

Styrofoam is difficult to recycle because it is mostly air and very lightweight, making it inefficient to transport and process. While it can technically be recycled, the low yield of usable material makes it impractical to do so on a large scale.