LAWR

November 2014 Local Authority Waste & Recycling 15 FOOD WASTE many authorities have adopted food waste collections, and these comply with the legal duty to apply the waste hierarchy, they are finding that such collections are not very effective. Traditional thinking is that because food waste is putrescible, is messy and smells, the only option is to collect it once a week – and that's expensive. As part of a large research programme funded by the European Community called Valorgas (www.valorgas.soton. ac.uk), Southampton University found that in the five European countries investigated, even after food waste col- lections were introduced, most food waste is still found in the residual waste stream. So the perception that food waste col- lection is not effective is correct – and the lack of participation by residents makes it an expensive service to oper- ate. Having to carry it out weekly over and above what may be a two-weekly based collection service just exacer- bates the problem. So the issue is how can participation be raised, and with local authorities having to cut costs, how can it be done as cheaply as possible whist remaining effective. Whilst the standard answer is more communication and education, it is unlikely that just having more leaf- lets and logos is not the answer. What is needed is something that engages with the psyche of the householder and makes disposing of food an almost natural thing to do. 'Engaging the user' Whilst it is not yet fully proven, there is a novel technology that may overcome most or all of these issues. Known as the 'Aerobic Bin', this as yet little known development could transform the storage and collection of food waste. Following three years of research at Imperial College, London, the Aerobic Bin combines science with sociology. It consists of a unique ventilated bin that holds a specially designed paper liner. The bag is waterproof and will contain liquid, but will allow vapour and air to pass through the fibres in the paper, keeping the food waste in aero- bic and stopping the problem of odour which attracts flies. The waste mass in the bag becomes subject to aerobic microbial activity, which causes the temperature to rise, thus evaporating the moisture content and drying the food waste. Not only does the waste not smell, it reduces in weight as it is stored. This means that food waste can eas- ily be kept in an Aerobic Bin for two weeks and collected with the alternate weekly collection, reducing the cost of vehicles, crews and disposal. Collection advantages aside, perhaps the most interesting aspect of the Aerobic Bin is the human interface. This is different to what has gone before, and if local authorities are to re- launch their education and behaviour change campaigns, they need some- thing different. The design of the bin is important, but the paper bag is key. It is required to allow the biodrying process to take place, but also keeps everything clean. The most interesting feature, how- ever, is that it seems to be better in engaging the user than a plain plastic bin. It may be coincidence, but in the Valorgas study, the best performing collection recorded was in Sweden and used a paper bag. Early trials carried out in Bexley, London, also indicated that there was a better engagement by the users than other collection systems. Maybe a clean paper bag liner makes the difference. It avoids the mess and the need to wash the bin every week. It seems to have a positive effect on the user participation and improve food waste capture rates. Of course, the Aerobic Bin may only be a small part of the answer, but if we can establish what really lies behind the psychology of waste collection, whilst putting more orderliness into the way we manage our waste at large, it will open up the future of recycling at large. A two-stream waste collection system may be a dream, but if we can get the people to engage with their waste, pro- gress can be made. This beautiful sum- mer must not be allowed to become the autumn of recycling in the UK. Let's not let the fatigue set in. Keith Riley is founder and chief executive of waste and environment consultancy Vismundi Consultancy. Food waste can represent anything from 16% to 18% of the waste produced by householders, according to Riley.

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