Processes, mechanics and management of wastes

Lead Research Organisation: University of Southampton
Department Name: Faculty of Engineering & the Environment

Abstract

Waste management is changing rapidly as the need to manage the earth's resources responsibly becomes increasingly accepted and enshrined in new legislation. Ideally, changes to the law, regulation and practice would be science-led; but in such a dynamic environment, scientific understanding and engineering know-how sometimes struggle to provide support with the result that the potential consequences of legislative and financial drivers for change may not be fully thought-through. For example, the EU Landfill Directive was enacted mainly to reduce fugitive greenhouse gas emissions from landfills, but its implementation with current treatment options could have the opposite effect. The aim of the Platform Grant is to provide the University of Southampton Waste Management Research Group with the stability and flexibility needed to explore new directions for its research that will provide the waste industry with the science and engineering needed for sustainable response to financial, regulatory and social drivers, and will address the legacy of unsolved problems arising from previous waste management practices. Key areas for development are:1) Field scale implementation of current research - enabling a rapid response when suitable study sites arise: We have developed the science needed by industry to reduce the long term pollution liability of landfills by a variety of remediation techniques, including flushing and in situ aerobic treatment. While excellent progress has been made, major uncertainties remain in upscaling from the laboratory to the field. This will be addressed in future research, in which we plan to investigate flushing and aeration at the field scale by running trials within discrete, bounded areas of MSW landfill(s) with the aim of significantly reducing the long term polluting potential of the wastes. 2) Resource recovery - second generation bio-based products and energy carriers from organic wastes and post-landfill processing: Government policy and strategic waste planning has highlighted a vital role for energy and commodity grade resource recovery in UK waste management practice. The infrastructure to facilitate this is already taking shape, through source segregated collection systems, growing markets for recovered products and pricing structures (e.g. ROC and feed-in tariffs) to encourage renewable energy production. The technology, however, is still in its infancy and underpinning research is urgently needed to support process engineering design, adapt existing technologies and exploit the potential for using waste as a raw material for biorefineries and solid recovered fuels. This will be done within an overall energy, materials and product recovery framework to include MSW processing operations where source segregation is not practised and also post-land filled wastes to reduce their long-term pollution potential and to create additional void space. 3) Application of recent and ongoing research to new forms of wastes - identifying key synergies: There is immense potential for translating the results of our current research into new areas, in particular in characterisation and near field contaminant transport modelling of low and very low level radioactive wastes.4) Development/promotion of a Sustainable Waste/Resource Management Forum including decision support systems (DSS - establishing expertise and stakeholder engagement, and maximising impact: DSS will make the results of the Group's research more readily available to users, encouraging knowledge transfer and maximising impact. Little work has been done to develop DSS for the waste industry, although the potential benefits have been recognised by some. DSS will also facilitate policy and operational decisions on the complex technology and process options available

Planned Impact

The WMRG is internationally recognised for its highly successful research programmes and the associated outreach and dissemination activities. A major factor in this has been the continuity of employment of its senior research staff, allowing them to engage with industry, regulators and government on waste and resource management topics. The Platform Grant will thus contribute significantly to the future of the waste management industry by providing a wide range of beneficiaries with continuing access to new knowledge. One aim of the proposal is to consolidate the knowledge now contained in our databases, models, documented experience and methods into more formalised decision support systems (DSS). This will have major impact by allowing the industry, including regulators and consultants involved in design and government departments responsible for policy and strategy, to access information in a much simpler and more user-friendly manner. The DSS concept extends across the topics considered in the application, but in the case of landfill aftercare a full DSS should be realised within the lifetime of the grant. This will provide a comprehensive analysis which, taken in combination with field scale remediation trials, will give improved confidence in aftercare provision and allow implementation of cost-effective management systems. Impacts will range from providing information to communities local to old landfill sites to giving site owners data on achievable and cost-effective engineering solutions, and planners a basis for the assessment of long-term economic and societal costs. More widely, current and future waste management options will be analysed using a range of LCA tools, allowing benchmarking and further development while providing improved datasets and reporting methods. The impact of this will be that Local Authorities and regional planners who are increasing called upon to consider ever more complex waste management treatment and recovery options, will have enhanced LCA toolkits that allow them to make decisions on process and management options in a consistent and transparent manner. The WMRG has helped to bring about the conceptual shift from waste to resource management, and the research will extend this by considering new approaches for enhanced materials and energy recovery from both fresh wastes and old landfills. This has positive impacts on natural resource sustainability, and on reducing greenhouse gas emissions and carbon footprints through energy substitution. Maximising benefits from the readily biodegradable fraction of waste is a key element of the work: development of sustainable nutrient cycles linking urban consumption to agricultural needs will play a major role in reducing environmental damage, while supporting the rural economy. As well as being carbon neutral energy sources, these biodegradable wastes can be used as feedstocks for second generation bio-based products, decreasing our reliance on oil and creating business development opportunities. We will also explore the prospects for resource recovery from waste already deposited in landfill sites, providing opportunities for the waste industry to diversity while freeing up airspace for re-use, to the benefit of local and regional planners. Research on containment systems has opened up new perspectives on the safety of some historic disposal sites, and tracer tests in landfills have provided baseline data for modelling the release and transport of contaminants. This knowledge could have a high impact on future policy and practice in the nuclear industry as it addresses the disposal of growing quantities of Low and Very Low Level radioactive waste. Transfer of our knowledge on soil-water interactions and our landfill modelling experience can contribute significantly to decision-making on sites for disposal of the 1.8 Mtonnes of VLLW expected from decommissioning of nuclear installations over the next few decades.

Publications

10 25 50
 
Description The fundamental landfill settlement framework that links waste composition, degradation, gassing and settlement.
Exploitation Route Through the sustainable landfill forum.
Sectors Environment,Other

URL https://landss.soton.ac.uk/
 
Description Highly downloaded papers by a range of users; established a very clear evidence based framework for the estimation of landfill settlement and the components of it. Extends framework to pre- and processed (post landfill directive) wastes.
First Year Of Impact 2014
Sector Environment
Impact Types Societal,Policy & public services

 
Title LANDSS website 
Description LANDSS is being developed as a Decision Support System (DSS) covering aspects of landfill engineering. The site has a particular emphasis on environmental control, sustainability and long term aftercare. It is being developed in consultation with stakeholders, through a landfill aftercare forum. 
Type Of Material Improvements to research infrastructure 
Provided To Others? No  
Impact None identified. 
URL https://landss.soton.ac.uk/Home
 
Title Mobile atmospheric methane monitoring 
Description The Tracer Gas Release technique uses gas tracers (typically acetylene) released at a known flux at or near a source of emitting methane. Concentrations of methane and the tracer gas are then measured downwind off site at locations where the gases are fully mixed. This enables whole site surveys of different sources of methane, such as composting sites, landfill, wetlands and anaerobic digestion sites. 
Type Of Material Technology assay or reagent 
Provided To Others? No  
Impact Too early to know. 
 
Title Development of online landfill modelling platform 
Description A coupled landfill processes model, first issued in 2017 and updated in 2018 and 2019. 
Type Of Material Computer model/algorithm 
Year Produced 2017 
Provided To Others? Yes  
Impact Utilization of model by other international research groups, including at Tongji University 
URL http://www.ldatmodel.com
 
Description International Symposium on Geohazards and Geomechanics 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Keynote lecture on geotechnical hazards associated with closed municipal solid waste landfill sites to an international audience. The Symposium brought together the complementary expertise of world leading groups carrying out research on the engineering assessment, prevention and mitigation of natural geohazards.
Year(s) Of Engagement Activity 2015
URL http://www2.warwick.ac.uk/fac/sci/eng/research/civil/geo/conference/presentations/william_powrie.pdf
 
Description LANDSS 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact A landfill aftercare forum has been established to provide stronger links between research and practice in the field of landfill management. An initial objective for the forum is to help direct Southampton's efforts to build a decision support system for landfill aftercare.
Year(s) Of Engagement Activity 2014,2015
URL https://landss.soton.ac.uk/Forum
 
Description LANDSS Landfill Aftercare Forum 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact A landfill aftercare forum has been established to provide stronger links between research and practice in the field of landfill management. The forum covers topics relating to improving landfill aftercare and includes oversees speakers to provide UK industry with an international perspective on challenges faced. The forum is open to anyone and regularly attracts over 100 delegates from a broad stakeholder group, including the public and private sectors, local authorities, consultants and academia.
Year(s) Of Engagement Activity 2016,2017,2018,2019
URL https://landss.soton.ac.uk/forum
 
Description Landfill Aftercare Forum, Birmingham, 2016 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact A forum for practitioners to improve national practice in the management of landfill sites. Participants included 8 academia, 36 consultants, 30 private sector, 17 local authority, 22 other public sector, 2 trade organisation and 1 independent.
Year(s) Of Engagement Activity 2016
URL https://landss.soton.ac.uk/
 
Description Uniwin lecture 2018 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact Prestige lecture at Institution of Civil Engineers: Transitions, Disruptors and the Quest for Sustainability (William Powrie). Some new technologies disrupt, and even those that do not often require complicated, systems-level transitions that are difficult to achieve quickly. The lecture illustrated these points with examples from energy and resource / waste management. It then critically assessed two ongoing efforts to achieve transformational change in transport: railway electrification and decarbonising our cities. Systemic failings
that have hindered success were identified. The lecture then discussed what we need from research if we are to do better in realising the benefits of technology in the future, while balancing the often-conflicting goals of affordability, equitability, improved environmental sustainability and quality of life.
Year(s) Of Engagement Activity 2018