All materials (even the ones that no one wants to discuss) are destined to become waste at one time or another and every production process generates some form of waste. The main strategic focus for preventing waste production should be reducing the environmental impact of that waste and the products that will become waste.
Lifecycle thinking requires greater knowledge of the impact of resource use on waste generation and management. Nappies, adult incontinence and feminine hygiene products which are known as Absorbent Hygiene Products (AHPs) go straight to the landfill or the incineration facilities along with the other waste.
Hence, landfill and incineration methods can’t handle the massive waste streams that are generated globally. A recycling strategy should aim to promote the recycling sector in order to reintroduce waste into the economic cycle in the form of quality products, while at the same time minimizing the negative environmental impact of doing so. The option of recycling AHPs is also possible now. Knowaste, AHP waste recycling specialist, has recently opened in West Bromwich the UK’s first-ever facility for recycling nappies, feminine hygiene and adult incontinence products. This with four more planned over four years, would be able to process 36,000 tonnes annually.
The Knowaste technology is used to clean, treat, recycle and recover energy from AHPs. The innovative, efficient, cost-effective and environmentally sensitive patented process deactivates the SAP and extracts plastic recyclate from the AHPs. The remaining cellulose fibre can be cleaned sufficiently for reuse or gasified to create electricity.
Advantages
• Diversion of untreated human waste from landfills, thereby reducing the contamination of underground water supplies
• 98% of nappy waste is diverted from landfill thereby dramatically reducing landfill gases, the main constituents of which are methane and carbon dioxide, both commonly known as green house gases, which form a surrounding layer around the earth trapping in heat
• The plastic components and organic residue from the nappies are reused or recycled
• The plastic is recycled into building products such as plastic wood, roof tiles, sidings and decking
• The organic residue is gasified to create green energy or it can also be used as a thickener for industrial products
• Enables local authorities and healthcare and daycare providers to face up to the challenges of ever tougher environmental legislation and increasing costs of sending waste to landfill
Knowaste can customise a recycling facility to meet the needs of a particular community or region through a large or small scale recycling facility. The process involves three key stages:
1. AHPs are collected and transported to a Knowaste plant.
2. The Knowaste process sterilizes the AHP material, deactivates and mechanically separates the individual components: organic residue, plastic and super absorbent polymers.
3. The reclaimed components can then be made into recycled products such as: Plastic wood, Plastic roofing tiles, Absorption materials, Process sweeteners, Recycled paper products and Green energy.
Absorbent Hygiene Products consist of three components: mixed plastic, wood pulp and super absorbent gel polymers. These components vary by product type, but are basically the same for all AHPs.
AHPs take 500 years to decompose and they contain human waste leading to contamination
Nappies and adult incontinence products have mixed plastic makes up the inner and outer layers. Wood pulp inside the nappy, cushions and wicks the moisture away from the skin and towards the inner core. Super absorbent polymers and gel-like capsules are located in the inner core, swelling and absorbing the moisture. All of these individual components of a disposable nappy or adult incontinence product can and should be recycled, effectively preventing an endless stream of negative environmental impacts associated with their disposal.
Stages
Used disposable nappies, adult incontinence and feminine hygiene products are collected and transported by a waste hauler to a Knowaste processor or plant. The Knowaste process sterilizes the AHP material and mechanically separates the individual components so the wood pulp and plastic can be recycled. Up to 98% of a used disposable nappy can be removed from the trash stream.
The plastics in nappies and/or adult incontinence products can be used in the production of plastic wood, roof shingles and vinyl wood sidings. The fibre and super absorbent polymers can make biogas or green energy or can be used as a thickener for industrial products.
• AHPs begin the recycling process by entering an autoclave that break them apart and sterilizes them. From here, the nappies are sent on to a pulper to begin processing.
• The next step washes the material and exposes it to a special chemical treatment to deactivate the super absorbent polymers. At the completion of this washing process, the plastic materials are removed and sent to a separate device for processing.
• Plastic components are again filtered and cleaned in a final washing cycle.
• The plastic is then compressed into small pellets that can be sold for easy reuse.
• Remaining parts of the absorbent hygiene product enter a screening process that captures any remaining traces of plastic and other organic material.
• To conserve resources throughout the recycling process, water is recaptured from each wash cycle and sent to an internal treatment device for clarification. The water is then reused in the Knowaste system.
• The remaining organic waste is dried and used to create Green Energy.
Knowaste’s recycling technology can be customised to support a small demonstration project in a single community or scaled-up to service a regional recycling program. This flexibility allows the company to market to a diverse and growing group of interests including waste management companies, local authorities, product manufacturers, hospitals, senior care facilities and many more.
Roy Brown, CEO of Knowaste, during the inauguration said: “We are developing partnerships with local authorities and their waste contractors to recycle domestic AHP waste in the future and our plant here in the Midlands and those intended for Scotland, the West and London will enable both commercial operators and local authorities to further cut carbon, increase recycling and divert waste from landfill.”
The AHPs for the West Midlands facility are being delivered to the site for processing by local, regional and national commercial waste operators, including OCS/Cannon Hygiene, PHS All Clear and Initial Rentokil. These operators collect this waste from washrooms, hospitals, nursing facilities and child care nurseries.
Mike Drake, Specialist Services Divisional Director at OCS, said the company will be responsible for delivering thousands of tonnes of AHP waste to the plant in Sandwell.
The majority of their collections will come from the Midlands and will include nappies, adult incontinence items and feminine hygiene items.
Drake said: “The operational opening of the Knowaste plant represents true progress for all organisations that collect absorbent hygiene waste.
“We are now able to move forward with improved sustainability, meeting both the business aims of OCS/Cannon Hygiene and many of our customers.”
In December 2010, Deloitte completed a Life Cycle Assessment (LCA) comparing the environmental performance of Knowaste’s recycling process with the existing UK disposal methods for AHPs, namely landfill and incineration.
The main findings were significant and showed that compared to these two options, the Knowaste recycling process emits up to 71% less carbon emissions and that the West Bromwich site would save 22,536 metric tonnes of greenhouse gas emissions per year.
This equates to:
• nearly 7,500 cars removed from UK roads
• The annual carbon emissions of more than 2000 UK citizens
• Over 100,000 LCD TVs switched off
Knowaste believes this same appetite for action exists in the public sector. With the building of capacity, in addition to the commercial sector, Knowaste is opening talks with local authorities with a view to treating domestic waste and helping the councils achieve higher recycling rates. Iain Gulland, Director of Zero Waste Scotland, said: “Achieving Scotland’s ambitious zero waste targets will require fresh thinking to recover the maximum value from all our resources.
“We are working to support Scottish councils who are looking at this new waste stream.”
All UK governments see diverting waste from landfill and recycling more as a priority; England targets 50% recycling by 2020. As a strategic aim of Zero Waste Scotland, the Scottish government targets 70% recycling of all wastes and no more than 5% landfill by 2025. Northern Ireland is setting a recycling target of 60% by 2020 and Wales’ Towards Zero Waste’ policy framework aims to reduce dependency on landfill and targets 70% of municipal waste being recycled or composted by 2020.
Knowaste joins other waste treatment operators in providing solutions that operate at a higher level of the waste hierarchy and which, along with waste prevention, can benefit the environment.
Facts on AHP waste
Population is rising fast, which will create more AHP waste.
• The world population of more than six billion people is set to increase to nearly eight billion people by 2025.
• The latest records in the UK by the National Statistics Office sets the population at 60.2 million and set to rise to 67 million by 2031. The use of disposable nappies has increased over the past 20 years as a result of their convenience. A baby will use 6,000 disposable nappies before being potty trained at an average age of 2.5 years.
• One baby’s disposable nappies fill 40 black sacks in a year.
• In the UK around three billion disposable nappies are used every year – generating about a half a million tonnes of waste. Adult incontinence product usage is rising as well.
• People are living longer.
• Baby boomers are retiring.
• The fastest growing age group in the UK is people over 80.
Feminine hygiene products also contribute to the growing problem of AHP use. In the UK, about 18 million women use sanitary protection products which generate over 200,000 tonnes of waste per year.
2 comments