Treat waste as a resource for sustainability, say engineers

The report – ‘Waste as a Resource: A sustainable Way Forward’ –  advocates an approach that prioritises waste streams according to their usefulness to materials and emissions reduction, as well as to their utility to the wider energy system.

The report is an update of a previous IMechE report, issued in 2009, and builds on that report’s advocacy to view waste not as a problem but rather as a resource. This requires a further rethink of recycling and waste policy.

In the report, the IMechE recommends that the government should:

• Replace the waste hierarchy with a model that genuinely delivers on the prevention of waste. The existing waste hierarchy has outlived its usefulness, the report states, and there needs to be a considerable reassessment of the way we view and deal with waste throughout the UK. The primary premise of its replacement must acknowledge that reducing or preventing waste of all types is paramount. Not producing the waste in the first place has by far the most beneficial effect on the environment.
• Release the value of our resources. Where ‘waste’ is inevitable and products not practically reusable, careful consideration must be given to achieve optimum use of all waste streams. Since waste is so diverse, it is obvious that there cannot be a single solution. Plants should be optimised so that some waste streams (e.g. metals, PET bottles) are given a ‘material-prioritisation’ strategy, while others (e.g. biodegradable materials) are given an ‘energy-prioritisation’ strategy.
• Adopt a zero-to-landfill approach. For many reasons (e.g. lack of new sites, the European Landfill Directive, environmental hazards), landfill is no longer an acceptable way of dealing with waste. ‘Zero-waste’ is not a ‘SMART’ (specific, measurable, achievable, realistic, and timed) objective, whereas a zero-to-landfill target is SMART and is much more likely to have a greater impact. It is also essential to have transparent, independently audited, published data on the recovery and destination markets of materials and energy (heat, transport, and electricity).
• A greater emphasis on all waste streams, not just household. Legislators should not just focus on waste from households (currently only 12 per cent of the total) and commercial and industrial waste (19 per cent), but start developing effective strategies for construction, demolition, and excavation (CD&E) waste (61 per cent) and other wastes (8 per cent).
• Use locally-produced waste to heat and power local communities. There must be a far greater degree of community involvement, the report suggests, envisaging a scenario (which already exists in other European countries) where a local community is responsible for its own waste and processes it into marketable products – e.g. electrical power, district heating and transport fuel, as well as recovered materials. The positive climate change mitigation (CCM) impact would be enormous, the report claims, as the transport of waste would be avoided and the community would have complete ownership of the whole process.

Professor Ian Arbon, lead author of the report, said: “We need to stop seeing waste as a problem and to start seeing it as a valuable resource and use it to maximum advantage. Our proposed modification to the waste hierarchy, which reduces it to four tiers, removes the unhelpful competition between ‘recycling’ and ‘recovery’ and helps to focus attention on minimising landfill.”

Matt Rooney, head of the IMechE’s Engineering Policy Unit,  said: “The UK could and should be making much better use of our waste streams. The recent cost-of-energy crisis has emphasised how important affordable domestic supplies of energy can be. The fact that so much waste heat from many of our power stations, for example, is simply lost to the atmosphere is something we need to change to build a more sustainable energy system.”

The full IMechE ‘Waste as a Resource’ report is available to download.