Professor David C. Wilson
Waste & Resources Management Consultant
Visiting Professor in Waste Management
Imperial College, London

Uncontrolled burning of solid waste as a significant contributor to climate change

To qualify for inclusion in the official (IPCC) inventory of greenhouse gases (GHGs), data for an emission source must meet a quality threshold. This currently excludes black carbon emissions from the open burning of wastes. The relative quantities may be small compared to carbon dioxide from fossil fuels or methane from landfill, but black carbon is around 2,000 more powerful than CO₂ as a GHG and has an even shorter half-life than methane. In the absence of real data, early modelling studies using broad assumptions suggested that black carbon from open burning contributes 5% of total global GHG emissions, causing 270,000 premature deaths a year. DCW’s PhD student at Imperial College London, Natalia Reyna, has been working for the last four years to provide real data which would meet the IPCC requirements. Our first paper, published this month in the leading journal Environmental Research, presents field data from Mexico on how much solid wastes are disposed of by open burning, either by households or at uncontrolled dumpsites. The results suggest a GHG contribution from uncontrolled burning in backyards in Mexico fifteen times larger compared to methane released from the decomposition of equivalent amounts of waste in a disposal site. This suggests that urgent action is needed to reduce domestic open burning of waste and that this would have a significant impact, both on improving local air quality and respiratory health, and on reducing climate change. A future paper will present data on emission factors, i.e. how much black carbon is produced by burning a kilogram of waste.

China: Coming Full Circle

China - coming full circle v3

China’s recent import ban has thrown Western recycling systems into disarray. DCW has participated as CIWM President in three regional open meetings to address the ‘China recycling crisis’. His April column for the CIWM Journal has written up his presentation, providing a personal perspective on how he has seen China’s internal resource and waste management systems develop over the last 40 years. Arguably, its 1970s system could be viewed as an early example of a circular economy. The transition to ‘market -oriented’ operations led to economic growth being prioritised over environmental protection. But the current ‘National Sword’ campaign is just one symptom of a fundamental change, suggesting that, going forward, perhaps China really could lead the world in transitioning to a circular economy.

Let’s Skip ‘The Tip’

Language matters. DCW’s March column for the CIWM Journal celebrates the dramatic improvements in waste and resource management that have been achieved since he first entered the sector in 1974. This is largely due to changes in public behaviour, which have enabled the UK, for example, to increase recycling rates over the last 20 years from just 6% to 46%. However, he questions how we can expect people’s mind set to change permanently when some local authorities, and both professionals and politicians, continue to refer to modern recycling facilities as ‘the rubbish tip’.

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Turning the Tide

DCW’s February column for the CIWM Journal focused on the topical subject of marine plastics. He reported back on ‘Oceans 21’, the latest Development Finance Forum organised by the German Development Bank KfW, where he led a workshop on marine litter. The conclusions were clear: the amount of plastics entering the oceans is at least an order of magnitude greater than estimates of the visible quantities in the oceans or on beaches – so the first priority is to ‘turn off the tap’. And the most effective way to do that is to extend municipal solid waste collection in developing countries to all people and to eliminate uncontrolled dumping and burning; our best judgement was that this could reduce the weight of plastics entering the oceans by 50-70%.

Inspiring Reuse

DCW’s January column for the CIWM Journal showcases the five shortlisted entries for the Best Reuse Project at the CIWM Sustainability and Resource Awards 2017. As the judge for this category, DCW was inspired by the quality and sheer variety of the five very different reuse projects. He hopes that the projects will inspire others too, as we try to ensure that reuse, sitting near the top of the waste hierarchy, receives the same priority as has been given to recycling.

A key utility service

In his first monthly column in the CIWM Journal as CIWM President, Professor David C. Wilson has revisited his Presidential address. His overall theme for the year is solid waste management as a key utility service, underpinning modern society. Within that three strands are to avoid complacency when it comes to protecting public health and the environment; the continuing move from the linear ‘make – use – dispose’ model to a more circular economy; and the global waste crisis, with more than 3 billion people lacking access to a basic solid waste management service.

DCW writes: ‘“Let us work together to promote the fact that solid waste management is one of the essential utility services underpinning our society. Let us ensure that the regular, daily delivery of that service to protect public health and the environment is not undermined, either by on-going cuts in local authority spending or by deregulation following Brexit”. And again: “It is simply unacceptable that 40% of the World’s population lack this basic utility service that we take for granted. We need to ensure that waste collection is extended to all people, and that uncontrolled dumping and open burning is eliminated.”