What Happens to Your Rubbish After Collection?

Every week, millions of people put their rubbish or recycling out for collection. But what happens to it after it’s been taken away?

General rubbish

Although almost two thirds of UK waste can be recycled, around half is still disposed of as general waste [1]. Every time something is thrown away, all the energy that was used to produce the raw materials, and produce, package, store and transport the finished product goes with it. General waste is disposed of in landfill or by incineration, both of which have environmental impacts. Why not consider using a compost bin to put your food waste in, therefore removing it from your general waste amount?

Tens of millions of tonnes of waste go to landfill each year in England and Wales alone [2]. The UK produces a higher proportion of biodegradable waste than most other European countries – about two thirds of waste going into landfill is this type, which releases the greenhouse gases methane and carbon dioxide as it decomposes [3]. Although some of this gas is captured at some sites to be used to generate energy [3], significant amounts of greenhouses gases are still released from landfill sites. Additionally, chemicals leached from waste can cause pollution, methane is explosive, and if waste is not well managed it can attract vermin [4]. The Landfill Directive states that by 2013, waste going to landfill should be 50% of that sent in 1995, while by 2015 it should 35% [5].

There have been concerns about waste incineration, due to release of toxins when some substances, such as plastics, are burnt and because of the contribution to air pollution [4]. The Environment Agency has found no evidence for risk to human health and only low contribution to background air pollution due to tight emissions regulations [2]. Energy can be produced from burning waste and all UK incinerators recapture some of the heat produced and supply it to the national grid, although Greenpeace consider this an inefficient way to produce energy [6]; Energy from Waste plants producing electricity, according the Environment Agency, are 25% efficient [2]. As there will always be some waste that cannot be reused or recycled, alternatives to landfill such as incineration will increase in use as landfill availability decreases, and incineration is considered preferable to landfill because it presents a higher rate of energy recovery and generates lower greenhouse gas emissions [2]. While the UK only recovered energy from 11% of municipal waste (waste from homes, schools, shops, small businesses and council waste collections) in 2006/07, Denmark were able to recover energy from 54% of theirs [2], so there is potential for improvement. However, incineration is only preferable to landfill for non-recyclable and non-reusable waste. Recycling can and should be increased [2].

Recycling

Materials that can be recycled as part of kerbside collections vary between local authorities, but recyclable items that can’t be collected can often be taken to local recycling points instead, such as those listed by Recycle Now [7]. Recycling items conserves fossil fuels, both as raw materials and through the energy used to make products, and reduces the amount of waste going into landfill. Common household recycled items go through various processes after collection and delivery at a Materials Recovery Facility (MRF) [8, 9]:

Plastic – different types of plastic, of which there are many, are sorted and broken down into flakes, cleaned, melted and then made back into a wide variety of new plastic or plastic-containing items
Glass – this is sorted by colour, crushed, melted and into new bottles and jars. This is more energy and resource efficient than creating brand new items. Recycled glass can also be used in fibre-glass and road surfacing. Over 80% of the glass collected for recycling is used in the UK
Cans and aerosols – these are sorted using a magnet and compressed, then melted and rolled out into a sheet. Aluminium is sold back to can makers, where it can be used in a new can within six weeks of its disposal, while steel is recycled in a wide range of way, for example in fridges, new cans, as components of machinery and in the construction industry
Paper – this is pulped at a mill and inks and staples, etc., are washed out. The pulp is then reduced in thickness between wire meshes, dried and rolled into reels. All of the newsprint in the UK is now made from recycled paper, which can be produced within a week of initial collection
Food waste – large-scale processing plants heat and sterilise food waste to remove bacteria, and it is then composted, which takes a few months
Clothing and shoes – these are sorted, then sent to UK charity shops or overseas to wherever they are needed

Much of these recycled materials are used in the UK, while some are exported to other countries such as China which, because they don’t have many raw resources, pay for recycled substances such as plastics – although this means transport of material, it is still preferable to extraction and processing of further raw materials [9].

The image below shows what happens to a plastic bottle, and associated implications, if it is thrown away in general rubbish, and when it is recycled [10].

In terms of which methods of waste reduction and disposal are the most environmentally friendly, Directgov lists five levels in the “waste hierarchy”: