Every few minutes another black speck appears in the distant sky as the next plane lines up to touch down at Heathrow. With 97 airlines based at its five terminals, serving around 70 million passengers a year, the world’s third busiest airport operates on a truly gargantuan scale.

For the airport’s landlord Heathrow Airport Limited (HAL) managing the waste generated by more than 320 large businesses across the site, not to mention rubbish discarded by travellers passing through, is extremely complex.

While around 110,000 tonnes of waste materials are generated each year at Heathrow, HAL only directly manages a quarter (26,000 tonnes) with the majority collected by other businesses operating at the airport.

The myriad of regulations and frameworks that HAL has to operate within also means that currently it is denied access to a large percentage of the waste materials generated.

“We’ve got a recycling rate of 37% and the reason for that seemingly low rate is partly due to the fact that all of the airside waste, aircraft cabin waste, currently has to be incinerated according to the EU’s Animal-by Product Regulations,” explains HAL’s waste & environment manager Mark Robertson. “It’s significant to us because 35% of our waste stream effectively is off-bounds.”

But that could all change thanks to a novel partnership that HAL has forged with Closed Loop Environmental Solutions (CLES).

As part of HAL’s on-going sustainability review, CLES carried out what is believed to be the first in-depth waste audit at Heathrow, using its Turnstile mobile material recovery facility (MRF) to analyse 100 tonnes of waste.

Setting up a small recycling site near Terminal 4, CLES took compactors from Terminals 1, 3 and 4, splitting them for waste generated by the terminals landside and airside to provide six seven-day trials between February and June.

After seeing the value of the data being produced, the partners then extended the project’s scope to include a cabin waste analysis from airlines.

“[Defra’s] animal health in particular has really helped us take this project forward,” says Robertson.

“When we looked at the airside compactors and the aircraft cabin waste, they were very proactive in how they helped us manage that, so that we were still compliant [with the regulations] but we could get in and get our hands on the material and work out what was in there.”

For CLES’ director Peter Goodwin, who oversaw the waste analysis trials on the Turnstile MRF, it was vital that a new approach was taken to ensure that the data collected was reliable.

“The historic approach to waste auditing has always been, take a percentage of the waste stream and make an assumption that is the make-up of the entire waste stream,” he explains. “[But] we needed to get granular data and that cannot be a historic approach. It needs to be a thorough analysis.”

By running all of the unsegregated material through Turnstile as an individual waste stream at half a tonne an hour so that all of the recyclable materials could be taken off and categorised, CLES was able to do a full compositional analysis of the waste collected during the trial.

The results will not only enable HAL to develop a clear business strategy on how it manages waste at Heathrow going forward, but it will also help CLES to engage with and influence the 3,000 stakeholders and 97 airlines so that ultimately the products they procure are designed for a closed loop market.

“Our fundamental business model is, why make something out of a material without consideration for its value post-use? If it hasn’t got a value post-use, then guess what, nobody is going to take it back,” says Goodwin.

“Whereas the waste industry has historically looked at, reactively, ‘what can we get out of the waste stream once it’s arrived in a compactor?’ Our focus is very much, ‘if what goes in at the front end isn’t 70% recyclable, then how are we going to get to a 70% recycling rate?'”

It’s a valid point because HAL has a strategic key performance indicator to recycle 70% of waste by 2020. Even so, early results have been encouraging.

Not only did the initial analysis reveal that there was more packaging waste and more waste in general that was suitable for recycling than previously thought but up to 60% of the aircraft cabin waste analysed could be recycled.

“We weren’t even sure there was 70% recycling in our waste stream. The results indicate that there is certainly over 50% and the recycling that is there is good material,” says Robertson.

“What we now need to do is go away, do a detailed analysis and work out how we can recover that material in such a condition that we can maximise the income we receive from it when we take it to the markets. We want our recycling to work for us financially.”

Some of the revenue generated from this material will be passed back to the airlines and stakeholders, which hopefully should influence their procurement decisions and ultimately stimulate a closed loop market at Heathrow.

“Reduced costs potentially also gives the opportunity for people to make procurement decisions that incorporate the consideration for material value post-use,” says Goodwin.

“The solution is for the airlines and the airport to be aligned in terms of their objectives. Ultimately, the airport needs to provide the [recycling] facilities to receive waste whereas the airlines need to present the waste in a way that the airport can receive it and it’s a win-win scenario.”

With this in mind, HAL and CLES are about to undertake a second piece of work with the International Air Transport Association, the governing body that regulates international air transport, to see how they can overcome the regulatory restrictions that would enable HAL to recycle cabin waste from aircraft landing at the airport.

“If we find a system of getting recycling off aircraft in a compliant way with the strictest regulations in the world, it’s got to be a winner for everybody else,” says Robertson.

Nick Warburton is editor of LAWR

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