TOPIC: The Waste Journey of Glass

With Scotland generating over 207,000 tonnes of glass waste in 2023 — but recovering only around 131,000 tonnes — there is still a huge opportunity to improve glass circularity. Jane opens with why glass recycling matters: it’s infinitely recyclable, supports the circular economy, and reduces reliance on virgin materials. But the journey is more complex than many realise.

Depending on where you live, glass might be collected kerbside (like Alasdair’s purple-lidded bin), mixed with cans and plastics (like Jane’s), or taken to bottle banks. Regardless, the ideal input is glass bottles and jars only — not Pyrex, window glass, ceramics or drinking glasses, all of which melt at different temperatures and contaminate the recycling stream.

Colour sorting remains important for closed-loop recycling, although modern facilities like Sibelco’s Newhouse plant can separate mixed glass into usable fractions. Surprising to both presenters, current market prices for clear, green, brown and mixed glass are broadly similar — raising questions about the cost–benefit of colour separation at collection.

Jane draws on her visit to the O-I glass factory, describing molten glass “dropping out in globules” before forming new bottles — a process as mesmerising as it is energy-intensive. Reprocessors can only include a certain proportion of recycled content to keep emissions manageable, balancing circularity with furnace performance.

Not all glass becomes bottles again. Some lower-grade material is turned into aggregate, sand substitute, shot-blast material or — interestingly — filtration media. Glass filters can reduce water treatment energy use, chemical demand, and fouling, making it a surprisingly high-value outlet despite its lower carbon savings.

Alasdair highlights European examples where beer bottles are standardised and endlessly reused — a system far more sustainable than recycling. Even at home, Jane recalls milk bottle return schemes as a reminder of how simple reuse can be. Could reuse make a comeback in the UK? Only if producers are pushed to redesign packaging systems.

The UK-wide DRS will exclude glass, unlike Wales, which plans to include it. That decision impacts kerbside systems, retail handling, safety concerns and producer behaviour. As Alasdair notes, omitting glass could lead to more plastic on the market — an unintended environmental consequence worth watching closely.

RUBBISH RANT: Christmas Over-Consumption

With Christmas approaching, Alasdair’s seasonal plea is simple: stop buying tat. From novelty gifts destined for the bin by January to pressure to over-consume at parties, the wastefulness is staggering.

Real or artificial trees? That debate continues, but the message remains: consume thoughtfully, reuse what you have, and resist the assumption that more stuff equals more celebration.

And a final reminder: WEEE and batteries should always be recycled properly — don’t put them in the bin. You can find out where to take them at: Recycle Your Electricals.