by Tom Freyberg
Tom, I'm pregnant. Those three words, normally enough to scare and excite a grown man at the same time, changed my life. And for the better, I should add! Around 21 months later and I now have a one-year-old daughter, full of the joys of life and developing quickly each day.
The journey of parenthood is not one that you can fully prepare for; sleepless nights, food slung everywhere and on-demand stand up entertainment required 24/7. The happiness it also brings to a family can also not be underestimated. Yet, there is another big factor most new families never quite get used to: nappies.
From the first day in the hospital, usually realising you've put one on back to front (apologies doctor, new parents you see!), to becoming so well versed in the practise you can do it in the dark, half asleep – disposable nappies are all part of the child-rearing experience. And also a big expense, I should add. Estimates suggest that on average, parents spend over £1000 on nappies over the first 2.5 years of a child's life.
With the UK producing around one million tonnes of this waste stream each year alone, it's estimated the country spends over £100 million disposing of nappies. Improved recycling efforts are also meaning the percentage of waste that nappies make up in a household is increasing. Traditionally thought to be 4% or less of domestic waste, levels in the "black bin" are now up to 8% or more.
Nappy waste has also caused multiple headaches for local authorities up and down the country. The introduction of alternate weekly collections (AWC), leaving nappies to fester away in residual bins for two weeks during summer months is forcing councils to take action and collect them separately.
"The introduction of AWC has meant that many authorities are now looking at alternative approaches to this waste stream," says Adam Read, practice director: resource efficiency & waste management, AEA. "For any local authority introducing AWC, residential concerns about odour are an issue that need to be addressed."
One example is in Wales. Cardiff Council and Monmouthshire County Council bit the bullet and introduced a nappy collection on the alternative week to residual waste collection.
The first six months were used to establish a collection method. It was decided that "Tiger-stripe bags" (bright yellow bags with a black stripe) were the best method.
As part of Resource Efficiency Wales (12 councils in Wales), Wales and Monmouthshire then started looking at alternative ways to dispose of the 10 tonnes of nappies generated each week. Discussions started with one company which believes it has the answer.
Originating from North America, Knowaste started researching technologies to recycle absorbent hygiene products (AHPs) since the 1990s. AHPs include disposable nappies, adult incontinence products and feminine hygiene products.
It was in 2011 that the company opened the UK's first AHP recycling facility in West Bromwich, Midlands, with a capacity of 36,000 tonnes. Commercial contracts, with waste contractors serving nursing and care homes, make up a large part of the company's business.
Yet the vast majority of the one million tonnes of nappies thrown away each year in the UK are by households. These became a lucrative target for Knowaste. After discussions with Cardiff and Monmouthshire, a six month collection trial started. Waste management firm Viridor collects the yellow bags and transports them to Knowaste for processing.
The Recycling Process – Plastics and Fibres
As any parent will confirm, the last phrase that springs to mind when throwing away used nappies is "valuable resource". Out of sight and out of mind is usually the preferred option for the heavy and smelly parcels joyfully left by your child. Knowaste approaches this differently.
"In the 1990s people would say to me it's not that big a stream and the Environment Protection Agency in the US and a number of other places that did waste audits said that this was around 2% of the entire waste stream," Knowaste CEO Roy Brown tells me.
"Today, because of the recycling and food waste, we can be easily 9-10% of the remaining stream. This is the next thing that has to be recycled. Right now it's the biggest item that hasn't been addressed properly."
So how does the process work? Autoclave technology is used to firstly sterilise the material, starting the separation of fibres and releasing moisture. Super absorbent polymers at this stage are rendered inert, according to the company.
A sorting and separation of plastics and fibres then follows, before the removal of contaminants. Plastics then continue through granulation and multiple-washing stages before flakes are bagged for shipping.
The latter can be used, or pelletised and then used, in new products such as plastic components or as an ingredient in composite materials. Fibres produced can be recycled into cardboard and biosolids from the nappies are sent to the sewer.
|The fibre content of the nappies can be recycled into cardboard|
As the plastic comes from one source, this, the company claims, is its unique selling point. Brown says he can supply the plastics recycling industry with a very "predictable product". One client – a manufacturer of recycled plastic roof tiles – quoted in a Knowaste video claims the "conformity" of plastics from nappy recycling is the same in every batch. With plastics from other recycling processes, this can differ, he says.
With collection trials spreading across the UK (four councils in Scotland have also started a trial, as well as one in Cheshire, England) and end product markets seemingly happy, it throws up one question: how does nappy recycling compare, environmentally, to other disposal routes?
In December 2010, financial services company Deloitte completed a Life Cycle Assessment (LCA). It compared AHP recycling against landfill and waste to energy. The LCA findings state that "compared to landfill and incineration, the Knowaste recycling process emits up to 71% less carbon emissions".
However, past reports throw up different findings. CE Delft in the Netherlands also published a report on nappy waste disposal back in 2007. It compared collection with incineration, with composting, with subsequent bio-digestion and Knowaste's recycling process. Results concluded "the first route, municipal incinerator, is the most attractive".
Report author Jan Vroonhof, now senior consultant at Royal Haskoning, says: "GHG emissions of incineration are a bit higher compared with composting and anaerobic digestion, but better for Kwowaste. GHG of incineration is higher as composting and digestion due to the incineration of SAPs [super-absorbent polymers] in the nappy pulp.
"These SAPs will not be decomposed in the composting and digestion, but remain in the compost and end product of the digestion. According to Agrotechnology & Food Sciences Group of the Wageningen University, this gives risks in using these end products."
The Dutch Experience and Cost Competition
Environmental results to one side, one of the biggest issues concerning local authorities – if collections are to be rolled out nationwide – is cost. If councils can dispose of nappy waste more cheaply per tonne in landfill gate fees, then this could prove an attractive alternative.
And cost was one of the deciding factors in forcing Knowaste to close its Arnhem facility in Holland in 2007. Set out with a capacity of 70,000 tonnes per year, the plant was only taking AHPs from the commercial market. Brown says that although they secured 60% of this market, it only accumulated to 40,000 tonnes a year.
"We couldn't really access the local authority market so our plant was always too big and under utilised and then in 2007 two incinerators opened up and then the price dropped," the CEO says.
"We were getting 126 Euros as our gate fee and doing fine with that. Then for the 2008 year our logistics partners said we would have to match 105 Euros per tonne and you should know the prices are going to carry on down. Today they are in the 90s. So our board made the right economic decision to exit that marketplace because the configuration of the plant we had at that time was fixed in terms of cost."
For its Midlands facility, it is clear that Knowaste realises it cannot take on landfill or waste to energy on gate fee alone. It has to be equally priced or else councils will opt for the cheaper option.
"If we're not competitive then we lose the business," says Brown. "So we have to be bang on competitive with the alternatives, whether it's incineration or landfill or composting. Our customers will not pay us a premium for having the best credentials in the world."
Even in the US, where Knowaste had a pilot plant, the cost per tonne to recycle nappy waste was a deciding factor. Treatment technology processing 7,000 tpa of AHPs in Southern California proved the technology could work, over a period of six months. Brown says that at the time in the US, he still couldn't match the cheap economics of landfill.
"It was $28 per tonne to throw it away [to landfill], and it was costing me about $45 per tonne to process it," he says. "We were there for the technical argument and that worked out quite well although we have found out there isn't really a market for such a small system."
For the Welsh local authorities, the cost appears to be competitive enough that talks are in place for a long-term contract with Knowaste, once the trial has finished.
"In terms of gate fees it is favourable to landfill. It's on a par/favourable to landfill disposal with the rising cost of landfill tax it's going to become more attractive each year," says James Kay, SE Wales Regional Waste Co-ordinator, Resource Efficiency Wales.
UK and Global Expansion
Other waste pundits believe the Knowaste business model, if it can compete for feedstock when other companies also start bidding, could locate plants across the rest of the country.
Peter Jones, ex-director of waste management company Biffa and director of consultancy Ecolateral, says: "There is scope for 20 other plants sized at 50,000 tonnes a year. Most likely, if they are autoclave based, they will migrate alongside those with surplus cheap heat since that is a significant component of costs."
For Knowaste, the estimate is more conservative. Brown says they plan to build five 36,000 tonne facilities across the UK, totalling around 180,000 tonnes. He also thinks the company should be able to capture a significant part of the 200,000 – 250,000 tpa commercial market.
Outside of its "owner and operator" business model approach in the UK, the company plans to expand internationally by licensing its technology. Germany, France, Japan and Australia are touted as the next countries where Knowaste expects licensees to put its process into action.
With the Netherlands's facility closure behind it and local authority trials gathering momentum, it appears Knowaste is in a strong position.
Maximising nappies collected from local authorities will be key to its success. As will remaining cost competitive to landfill and waste to energy, with council budgets getting ever smaller. If the company does reach its target of five plants processing nearly 200,000 tonnes of nappy waste, that is still only scratching the surface of the one million tonnes disposed of in the UK each year.
Parents opting for disposable over reusable nappies inevitably feel a twinge of environmental guilt each time they throw one away. With Knowaste's process, it seems they don't need to.
Tom Freyberg is the chief editor of WMW magazine.
Nappy Recycling Trials Spread from Wales to Scotland
A kerbside collection trial is underway in several areas in Scotland to help recycle the 160 million nappies landfilled every year in the country into roof tiles and benches.
Welsh Councils to Recycle Nappies and AHP Waste
Absorbent hygiene products (AHP), including disposable nappies, adult incontinence and feminine hygiene products are to be recycled as part of a trial by Monmouthshire County Council and Cardiff City Council.
Reasons to be Cheerful
While the general air of economic and political malaise seems to have set in for the long-haul, with double 'dip recessions' and 'austerity measures' making regular appearances in world news, for the waste industry there's plenty of room for optimism.