“What do you think happens to the rubbish when you throw it out into the street?” asks the Mighty Boosh’s great realist Howard Moon.
“I don’t know, does it dissolve in the rain like a giant Berocca?” replies Shoreditch everyman Vince Noir.
Inconveniently, however, those black bags endure. In the UK half of all household waste, tens of millions of tonnes ends up on the tip face. Waste management processes, such as recycling, have been developed to cut down on landfill and the EU’s recycling targets mean that countries that do not meet their reduction targets may be punished. In order to meet these ambitions many countries (especially in northern Europe) have clambered just one rung above landfill by burning instead of burying.
But technological developments and behavioural changes are bringing us to the brink of a world in which we not only stop burying our everyday gremlins, but dig up those of yesterday and turn them into useful stuff. Where methane-belching landfill sites are replaced by high-tech processing plants that turn trash into building materials, electricity and gas. It seems impossible but a waste-free society could be just around the corner.
The end of incineration?
There are a number of reasons why incineration is one of the least preferred measures of waste disposal, not least because it is inefficient. Typical waste incinerators are 5-10% less efficient than fossil fuel power stations. Incinerators also create their own problematic waste by-products.
British company Advanced Plasma Power (APP) claim to have a solution that is clean, efficient and creates almost no by-products. Their demonstration plant in Swindon is trialling a process that could eventually transform landfill and incineration into memories of a wasteful past.
The APP plant sorts recyclables from general waste, then shreds the leftovers and dries them in an oven. The dehydrated pellets are then put into a cylinder called a fluid bed gasifier, which sounds like something I just made up, but they assure me it is real. There is a bed of sand in the chamber that, when hit by jets of steam and oxygen becomes “fluidised”. The highly energetic sand breaks apart the molecular bonds in the rubbish, leaving behind a gas which is mostly hydrogen and carbon monoxide, but also contains ash and other complicated organic materials. This gas is then fed into a compartment where it is essentially hit with a lightning bolt. The massive electrical charge turns it into plasma. This separates out the impurities creating a clean stream of gas as well as a stable, vitrified substance that holds all the potentially nasty heavy metals, APP call it Plasmarok. The UK Environment Agency has approved Plasmarok as a safe material for use as a building aggregate.
A typical plant will process up to 170,000 tonnes of rubbish each year, which is about the same amount collected by Manchester city council in 2012. This would create enough gas to generate 20MW of electricity. The process will use 5MW. The net gain of electricity means a plant could power 6750-9000 homes. Around 20,000 tonnes of aggregate will also be created.
Electricity generation is only one potential use for the end products. The gas could also be fed directly into the national grid. Or used to create hydrogen, which may well be the gas of the future if hydrogen cars become an everyday reality.
But the company has so far failed to get rid of waste entirely. Around 1,000 tonnes of ash that is currently untreatable is produced and will have to go into a sealed landfill site. The company says it is working on uses for this as well.
The challenge for this type of technology is to become self-sustaining. APP’s chief executive officer Rolf Stein says the potential income streams are “endless”. He says the process “already offers better returns to investors than conventional technologies [ie incinerators] and this will only increase as the downstream processing options and relevant markets are further developed”. The economic case is aided by the payments for which plants would be eligible for diverting waste from landfill.
But William Neale, a member of the European Commission’s (EC) environment cabinet, says one of the problems for incinerators has been that they bind countries into burning waste rather than developing new ways to recycle.
“Once you build incinerators, they are there for 50 years or so and you have to feed the monster.” Zero Waste Europe‘s associate director Mariel Vilella says this technology is no different, describing it as a red herring. “Even if this was safe, would it be sensible to spend so much money in destroying resources that ought to be shared with future generations?” A project in Belgium, where old rubbish is actually being dug up, may provide a way for this waste to energy to coexist with recycling.
Digging up the old
Historic landfill is full of useful rubbish, buried before we had the ability or inclination to recycle it. At the Remo landfill site in Flanders, trials have been successfully conducted to show the potential for digging up old waste and separating out material we can use. Around 45% of the buried material is estimated to be reusable. Millions of tonnes of glass, ceramics, ferrous and non-ferrous metals, plastics, paper, wood and textiles lie below, awaiting resurrection. The left overs can be used to generate energy.
Neale says the process is close to being economically viable. “Waste is becoming, in certain circumstances, so valuable that you could actually consider going in to old landfill.”
Last month, the European commission granted permission for APP to build a plant at the Remo site. The Enhanced Landfill Mining Consortium (ELMC), a cooperate initiative between APP and other companies, is now seeking investment of €50m-55m (£40m-£44m) for the project. They expect to be operating by 2016.
The big advantage of landfill mining for the energy making process is that it scales it up hugely, enhancing the economic potential. The amount of waste coming in from local municipal and industrial rubbish is nothing compared to how much of it is already under our feet. There are an estimated 150,000-500,000 landfill sites in Europe, holding billions of tonnes of rubbish. The Remo site alone holds 16.5 million tonnes. The ELMC say this would make a plant viable for around 30 years. After this the site could be regenerated. If the process was installed across Britain, APP says it could supply 20% of the country’s gas.
Divide and conquer
Also being trialled at the Remo site is the separation and temporary storage of rubbish. Tom Jones from the ELMC says “this is basically a way to store certain fractions [of waste] which are not yet recoverable today, but we do not want to incinerate them today, so we want to keep them in such a way that we can recover them in the near future”. One example is the storage of asbestos, which can be vitrified in an APP plant, turning the old hazard into a safe building material. This only way to make this process cost-effective, however, is to have a large amount of asbestos stored up.
Again, the issue is cost. But Jones says building up large caches of homogenous waste that can be easily dug up will eventually make these approaches possible. Although the approach makes sense in theory, Neale says the EC has concerns about it expanding. “The difficulty that we have legally is that we don’t want to create loopholes. Because although the organisations that are doing it now have got very good reasons for wanting to develop this temporary storage idea, it might be used by others as a loophole to get around the targets for reducing landfill, if they can say ‘oh it isn’t landfill, it’s temporary storage’.”
Technology good, people better
In the end though, people’s behaviour is by far the biggest factor governing how much waste we produce, says Vilella. “To reach waste prevention targets, you need to think of social innovation, not technology innovation.” Reduce, reuse, recycle is a familiar adage. But there are very few places in the world that actually do it well.
Primarily, people must be encouraged to reduce how much they throw away, either through smarter consumption or reuse. The impact of correct recycling processes can also be enormous. But Vilella says people must be motivated to be involved.
In the Italian town of Capannori, this motivation came from a threat. In 2005, 60% of the town’s trash was going to landfill. Residents were told an incinerator would be built in order to burn the excess for energy. Knowing incinerators can produce harmful emissions, locals mobilised against the development. By educating the public and providing a rigid schedule for separate waste collection the town managed significantly reduce total levels of collected rubbish and now operates a recycling rate of 80-90%.
“The successful results of zero waste towns in southern Europe can be reproduced in any municipality across Europe,” says Vilella. “The key is to set up a new direction away from landfills and incinerators and invest in flexible systems that allow to continuously reduce the waste that cannot be recycled or composted.”
A society with almost no waste is coming. But can we get to zero waste? Joe Ross, director of the Biorenewables Development Centre in York, says we are heading in the right direction and a world of very little waste is conceivable. But zero might be a stretch. “It’s a journey we are all on. When it will happen and to what degree it will happen is very difficult to know. Whether we can get down to zero, that’s a very challenging target.”
But Iain Gulland, the director of Zero Waste Scotland, says the idea of zero waste is not so much about how much ends up in landfill, as how much is unnecessarily wasted. “Zero waste is fundamentally about a change of mindset. It’s about seeing all the materials circulating in our economies as resources, not waste, and keeping them in a high-value state for as long as possible. Based on that understanding, zero waste is absolutely achievable.
The end of waste is not a story about technology riding in on a white horse to save us from drowning in our own unavoidable filth. It is remarkable that in the UK, where landfill space is rapidly running out, the municipal recycling rate was just 43.2% last year. With clever social projects, towns such as Capannori have doubled this in less than a decade. As it turns out, the best technology is already available to us.
• This article was amended on 13 June 2014 to remove an incorrect reference to “the EU’s landfill tax”; there are EU recycling targets but the landfill tax is a UK tax. The earlier version of the article also erred in describing William Neale as a British MEP.
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