How Recycling Works
Recycling is the process of collecting used materials — paper, plastic, metal and glass — and breaking them down so they can be remade into new products instead of being buried or burnt. In Singapore, where landfill space on Pulau Semakau is limited, this process starts at the blue bin outside most HDB blocks and ends at a factory turning old material into something new.
The journey has five stages. A household sorts clean paper, plastic, metal and glass into the blue bin, keeping food scraps and dirty items out. A recycling truck collects every bin into one mixed load and delivers it to a Materials Recovery Facility (MRF). There, machines separate the pile: magnets lift steel cans, air blowers push out lightweight plastics, and different materials end up in separate streams. Each stream is then cleaned, crushed and melted, destroying the old shape entirely. Finally the raw material is remoulded — a drink bottle can become fabric fibre, and old paper becomes new paper.
The key idea learners grasp is contamination: one wet or dirty item can spoil the clean paper around it, sending the whole batch to the incinerator instead.
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Where does your bottle go?Nothing is wasted! Where does your drink bottle go? You finish your drink. You drop the bottle into the blue bin near your HDB block. Then… it vanishes! But it doesn't really vanish. That bottle goes on a long journey — a truck ride, a giant sorting machine, a wash, a melt — and comes back as something brand new. In Singapore we call this the recycling loop. In the next few slides you'll follow one bottle all the way around it. 🎯 Your mission: learn the 5 steps of recycling — and find out the one mistake that spoils the whole batch.
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Step 1: Sort at homeStep 1 — You sort it 🏠 Recycling starts with you. In Singapore, the 🔵 Blue Bin takes paper, plastic, metal and glass. Food scraps and dirty things go in the 🟢 Rubbish Bin. Tap an item, then tap the bin it belongs in. Try all 4! 📰Newspaper 🥫Empty tin can 🍚Leftover rice 🧴Rinsed bottle Blue Binrecycling Rubbish Bingeneral waste
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Step 2: The truck collectsStep 2 — The truck collects it 🚛 A recycling truck comes round the neighbourhood and empties every blue bin into one big load. Then it drives to a Materials Recovery Facility — a huge sorting factory. People call it the MRF for short. MRF Tap the truck to start the drive 🚛 Drive to the MRF 💡 One truckload can hold the recycling of a whole street — that's why the bins are emptied together, not one bottle at a time.
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Step 3: Machines sort itStep 3 — Machines sort the pile 🧲 At the MRF everything is mixed together, so clever machines split it apart: 🧲 Magnet pulls up steel cans 💨 Air blower lifts light paper 👀 Workers pick out mistakes A steel can and a paper sheet are stuck together on the belt. Which machine picks up the steel can? steel can paper 🧲 The magnet 💨 The air blower 💧 A water jet
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Step 4: Clean, crush, meltStep 4 — Clean, crush, melt 🔥 Now all the bottles are in one pile. To become new plastic they go through three steps. The old shape has to disappear completely! 🫧 wash → 🔩 crush → 🔥 melt Put the three steps in the right order. Tap the chips 1 → 2 → 3. 1 2 3 Melt into liquid Wash off the dirt Crush into small flakes 🔥 Melted plastic is poured into tiny beads called pellets. Factories buy pellets the way a baker buys flour — as the raw ingredient.
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Step 5: It becomes something newStep 5 — It becomes something new ✨ This is the fun part. The old material is now a raw ingredient, so a factory can make a completely different thing out of it. Tap each card to see what it can turn into. 🧴 Plastic bottle 📰 Old newspaper 🥫 Metal can 🍾 Glass bottle ♻️ Making a can from recycled metal uses far less energy than digging up new metal from the ground. Recycling saves energy, not just space.
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The one big mistakeThe one big mistake 🚫 Here's the secret most people don't know. If you put something dirty or wet into the blue bin, it can spoil the clean paper around it. Wet, food-stained paper can't be recycled — so a whole bag can end up as rubbish. This spoiling is called contamination. Find the one item that does not belong in the blue bin. Tap it. 📦Flattened cardboard box 🍕Greasy pizza box with food 🧴Rinsed shampoo bottle 🥫Washed tin can ✅ Golden rule: empty it, give it a quick rinse, let it dry — then bin it. Clean recycling is good recycling.
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You closed the loop!♻️ the loop Sort → Collect → Machines → Melt → New thing You followed the whole journey! 🎉 1. Sort at home — blue bin for paper, plastic, metal, glass. 2. Collect — the truck takes it all to the MRF sorting factory. 3. Machines sort — magnets grab metal, air lifts paper, workers check. 4. Clean, crush, melt — the old shape disappears into pellets. 5. Made new — bottles become shirts, cans become bicycles. 🚫 And the one rule that beats all the others: keep it clean and dry, or contamination spoils the batch. 🏅 Recycling Loop Champion Tonight, rinse one item and put it in the blue bin. You now k
Frequently asked questions
- What can go into the blue recycling bin in Singapore?
- Paper, plastic, metal and glass items belong in the blue bin, and they should be reasonably clean and dry. Food waste, used tissues, soiled containers and disposable cutlery do not — they go into the regular green refuse chute or bin.
- Do I need to wash my drink bottles before recycling them?
- A quick rinse is enough — you are removing leftover liquid and food, not scrubbing it spotless. Liquid left in a bottle can soak the paper sitting next to it in the bin, and wet paper can no longer be recycled.
- What happens at a Materials Recovery Facility?
- Everything arrives mixed together, so machines pull the pile apart: magnets attract steel cans, air blowers lift light plastics, and screens and sorters separate paper from heavier items. Each material leaves as its own clean stream ready for cleaning, crushing and melting.
- Why does one dirty item matter so much?
- Recycling is processed in large batches, not item by item. A leaking cup or a half-eaten meal can contaminate the clean paper and cardboard around it, and once that batch is soiled it is sent for incineration rather than remade.
- Does a recycled plastic bottle become another plastic bottle?
- Not usually. After it is melted down the plastic becomes a raw ingredient, so a factory can make something completely different from it — plastic bottles are often turned into fibre for clothing, bags or carpets.
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