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Diverting organic waste from landfills provides significant emissions benefits in addition to preserving landfill capacity and creating value-added energy and compost products. Dry anaerobic digestion (AD) is particularly attractive for managing the organic fraction of municipal solid waste because of its high-solids composition and minimal water requirements. This study utilizes empirical data from operational facilities in California in order to explore the key drivers of dry AD facility profitability, impacts of market forces, and the efficacy of policy incentives. The study finds that dry AD facilities can achieve meaningful economies of scale with organic waste intake amounts larger than 75,000 tonnes per year. Materials handling costs, including the disposal of inorganic residuals from contaminated waste streams and post-digester mass (digestate) management, are both the largest and the most uncertain facility costs. Facilities that utilize the biogas for vehicle fueling and earn associated fuel credits collect revenues that are 4-6x greater than those of facilities generating and selling electricity and 10-12x greater than facilities selling natural gas at market prices. The results suggest important facility design elements and enabling policies to support an increased scale of organic waste handling infrastructure.

Managing waste is a crucial challenge for modern societies. The UK government has established ambitious targets in terms of landfill diversion for household waste. Household Waste Recycling Centres represent key facilities for achieving these targets. However, Local Authority budgets are under severe strain due to reductions in central government transfers. As such, local councils often need to perform reconfigurations of the recycling centres networks, by reducing the number of sites or their opening hours while still offering adequate service levels. Central to being able to do this, is understanding the spatial patterns of access to such centres. Therefore, this paper develops a spatial interaction model aimed at examining and exploring users’ behaviour and preferences when choosing recycling centres. Specifically, an origin-constrained gravity model is developed; through a careful estimation of its attractiveness parameters, the model is capable of describing demand flows from Sheffield City Council districts to Household Waste Recycling Facilities. The results are compared to actual data obtained through a users’ survey from an English Local Authority. The high level of correlation between the results provided by the model and actual users’ preferences indicates that the model can be a valuable tool in describing users’ behaviour in accessing the service. Based on this, the model can be employed in order to estimate the impacts of modifications to the network configuration on users, performing scenario analyses and providing useful suggestions to planners.

Anaerobic digestion of organic fractions of municipal solid waste (OFMSWs) represents a promising solution to achieve greater landfill diversion and resource recycling. The objectives of this study were (a) to explore potential synergistic effects on methane production in co-digestion of organic MSW components with distinct biodegradabilities, and (b) to evaluate whether and how the inoculum source and substrate composition affected methane production and microbial community composition. Anaerobic mono- and co-digestion of food waste (FW), newspaper (NP) and branch (BR) were conducted in a batch culture system inoculated with landfill leachate (LL) and anaerobic sludge (AS) under mesophilic conditions. The 16S rRNA sequencing based community analysis revealed that the microbial communities consisted of taxonomically diverse but methane yielding populations, and were primarily influenced by their inoculum. The methane generation results showed that co-digestion of readily degradable FW with more recalcitrant lignocellulosic NP and/or BR, only resulted in additive effects on the cumulative yields, but synergistic effects on the production rates (up to 22% yield increase between 10 to 15 days). This early synergism was primarily associated with the accelerated hydrolysis due to the FW addition to promote the growth of hydrolysis microorganisms. These results suggest that multi-component feedstock (e.g., OFMSWs) is preferred for efficient AD systems and brings in early synergism benefits for process optimization in practice.

High-density polyethylene is an important polymer for a variety of industrial applications. The pressure for landfill diversion strategies have increased with consumer awareness of traditional end-of-life practices. It is critical to understand the influence of post-consumer recycled polymer (PCR) content on properties and consumer safety as converters blend PCR with virgin resin to increase sustainability. The ability to empirically quantify the PCR content is vital for compliance with minimum content laws. This work determined ∼380% increase in UVA absorption, increased carbonyl and terminal vinyl functional groups, a 50% reduction of fluorescence properties, a reduction of the polymer crystal quality, and a ∼4 °C increase in the degradation temperature. The extractables content of all PCR blends complied with the Code of Federal Regulations for direct food contact applications. Trends between the measured properties and PCR content identified potential certification markers for empirical quantification of PCR content and single-measurement quality control metrics.

Separate household food waste collection for anaerobic digestion is one method used in the sustainable management of biodegradable municipal solid waste (MSW). Recycling of food waste contributes to the UK’s reuse, recycling and composting targets and can help local authorities boost plateauing rates whilst encouraging landfill diversion. This study explored the reasons for differences in the provision of food waste collections, using two comparable local authorities, one with a collection in Wales (Cardiff), and the other absent of such service in England (Southampton). A PESTLE analysis investigated the political, economic, social, technological, legal and environmental impacts of separate food waste collections. The greenhouse gas impacts of the collection and treatment systems of MSW in both cities were estimated for 2012/13. Results showed significant policy and legislative differences between devolved governments, that separate food waste collections can save local authorities significant sums of money and substantially reduce greenhouse gas impacts. A survey of one hundred respondents in each city aimed to understand attitudes and behaviours towards recycling, food waste segregation, cooking and purchasing habits. The number of frequent recyclers and levels of satisfaction were higher in the authority which provided a separate food waste collection. In the area which lacked a separate collection service, over three-quarters of respondents would participate in such a scheme if it were available.

When assessing the environmental and human health impact of a municipal food waste (FW) management system waste managers typically rely on the principles of the waste hierarchy; using metrics such as the mass or rate of waste that is 'prepared for recycling,' 'recovered for energy,' or 'sent to landfill.' These metrics measure the collection and sorting efficiency of a waste system but are incapable of determining the efficiency of a system to turn waste into a valuable resource. In this study a life cycle approach was employed using a system boundary that includes the entire waste service provision from collection to safe end-use or disposal. A life cycle inventory of seven waste management systems was calculated, including the first service wide inventory of FW management through kitchen in-sink disposal (food waste disposer). Results describe the mass, energy and water balance of each system along with key emissions profile. It was demonstrated that the energy balance can differ significantly from its' energy generation, exemplified by mechanical biological treatment, which was the best system for generating energy from waste but only 5th best for net-energy generation. Furthermore, the energy balance of kitchen in-sink disposal was shown to be reduced because 31% of volatile solids were lost in pre-treatment. The study also confirmed that higher FW landfill diversion rates were critical for reducing many harmful emissions to air and water. Although, mass-balance analysis showed that the alternative end-use of the FW material may still contain high impact pollutants.

The selection of an appropriate technology for waste management in a way that enhances sustainability is a complex problem requiring information from multiple disciplines. This decision is made more complex for large, diverse organizations for which individual sites or components have different requirements and capacities for waste management. For U.S. Army installations, sustainable waste management is a major obstacle for resource constrained and overburdened installation personnel. The Army has prioritized landfill diversion at installations; there is a significant push for each installation to develop and implement waste management plans that follow high-level goals set by U.S. Army Installation Management Command (IMCOM). The main objective of this study is to demonstrate an excel-based dashboard tool incorporating Multi-Criteria Decision Analysis (MCDA) for site-specific waste management technology selection. The dashboard uses the preferences of an installation and a series of weighted metrics to evaluate technologies. With this information the dashboard can rank the technologies to identify those that simultaneously meet IMCOM's objectives and are appropriate for specific sites' capabilities and resources. Fourteen different technology makes and models were compared in this version of the decision model including dehydrators, pulpers, garbage disposals, containerized in-vessel composting, windrow composting, forced-air static composting, and containerized anaerobic digestion. MCDA provides for transparent comparison of technologies for all sites, and the dashboard visualizes the level of appropriateness of each technology for each site. The approach developed here adds value in that it utilizes the priorities of the organization and identifies the best performing waste management technology given the specific capacity and capabilities of an individual site.

The city of Makkah in the Kingdom of Saudi Arabia (KSA) hosts millions of Muslim worshippers every year. As a consequence, the municipal solid waste (MSW) quantities become enormous. City landfills receive about 2.4 thousand tons of MSW every day, whilst during the months of fasting (Ramadan) and Pilgrimage (Hajj), these quantities become 3.1 and 4.6 thousand tons per day respectively. Currently, there is no waste-based biorefinery or waste-to-energy (WTE) facility existing in KSA to treat different fractions of MSW as a source of renewable energy production and a solution to landfill waste problems. Therefore, the waste-based biorefinery, if developed in Makkah city, including WTE technologies such as anaerobic digestion (AD), transesterification, pyrolysis and refuse derived fuel (RDF) can be able to treat around 87.8% of the total MSW. The remaining 12.2% of MSW fraction can be recycled. The waste-based biorefinery, along with the recycling approach, can generate savings of about 87.6 million Saudi Arabian Riyal (SAR) from carbon credits. Similarly, a total net revenue of 758 million SAR can be generated from landfill diversion (530.4 million SAR) and electricity generation (288.5 million SAR). Moreover, 1.95 million barrels of oil and 11.2 million MCF of natural gas can be saved with a cost savings of 485.5 million SAR. Collectively, the waste-based biorefinery and recycling can reduce the global warming potential (GWP) of 1.15 million Mt.CO2 eq.

In the United States of America (U.S.) almost all of the food waste generated is ends up in landfills. Centralized systems of composting have been effective at diverting large volumes of food waste. However, they require considerable capital investments and face operational challenges. As solid waste planning practices vary across national geographies, this study primarily focuses on the application of decentralized composting within the U.S. This study advocates decentralized composting for its anticipated benefits of outreach, landfill diversion, and cost savings. Using Chicago as a case study, the recovery potential and challenges of using a portion of public parks for community composting are explored. Community characteristics are incorporated in the numerical and spatial analysis of food waste generation and capture potential. This study also conducts a preliminary cost and greenhouse gas (GHG) emissions impact analysis, comparing the proposed community composting to current food waste processing systems. The results demonstrate the viability of decentralized composting to divert substantial volumes of food waste, as a complementary strategy to other landfill diversion programs. Policy recommendations are provided to facilitate the implementation and increase the efficiency of decentralized composting programs.

A municipality with 90,000 inhabitants located in Central Brazil undertook to attract recycling enterprises. This study identifies the basic strategy of a household waste management model that would provide a steady supply of raw materials for the industry within a time frame of 20 years. It developed the concept of sorted-waste composition to drive reverse logistics and ancillary industry. The domestic waste production rate was 45 tons/day, and the immediate diversion potential stood at 67%. Annual progress indicators required to reach this potential within the given timeframe are detailed. Reverse logistics operators were found capable of removing all inert waste items separated at source. The necessary logistics for biodegradable matter are outlined. With the long-term guaranteed increase of recyclable material, a favourable environment for prospective industrial enterprises was constructed, and the challenge of the municipal administration was reduced to promoting source separation.

Waste generation and waste disposal are issues that are becoming increasingly prominent in the environmental arena both from a policy perspective and in the context of delinking analysis. Waste generation is still increasing proportionally with income, and economic and environmental costs associated to landfilling are also increasing. Thus, the need of accelerating the eventual delinking process by the introduction of policies at all stages of waste production and disposal. This paper provides a comprehensive analysis of waste generation, incineration, recycling and landfill dynamics based on panel data for the EU25, to assess the effects of different drivers (economic, structural, policies) and the eventual heterogeneity on such evidence between western and eastern EU countries. We show that for waste generation there is still no absolute delinking trend, although elasticity to income drivers appears lower than in the past. Landfill and other policy effects do not seem to provide backward incentives for waste prevention. Regarding landfill and incineration, the two trends, as expected, are respectively decreasing and increasing, with policy effects providing a strong driver. It demonstrates the effectiveness of policy even in this early stage of policy implementation. This is essential for an ex post evaluation of existing landfill and incineration directives. Nevertheless, it signals the risk of widening gaps between early adopters and countries which postpone ratification and implementation. It is also worth noting that EU15 and EU10 groups of countries show some different waste trends and driving forces of waste generation and landfill diversion hen analysed separately. We may conclude that although complete delinking is far from being achieved – especially for waste generation, there are some positive signals, and signs of a quite significant role of the EU waste policies implemented in the late 1990s and early 2000s.

Energy-from-waste (EfW) policies can provide an essential part of landfill diversion and climate change strategies. Many UK waste disposal authorities (WDAs) are currently deciding which energy-from-waste policies are most suitable for their respective municipal areas. Such decisions are challenging since the environmental, economic and social implications of any EfW policy must be fully considered, now that planning guidelines require a full Sustainability Assessment. More specifically, WDAs must identify suitable site locations for facilities, and the optimal scale and number of facilities. This paper reports the results from a study that has developed and appraised EfW policy options using Geographical Information Systems and Multi Criteria Analysis modelling. These methods were used to evaluate and compare the impacts of several EfW strategies in the UK administrative areas of Cornwall and Warwickshire. Different strategies have been defined by the size and number of the EfW facilities, as well as the technology chosen, which includes conventional incineration and advanced thermal treatment. The overall conclusion of this work is that distributed small-scale EfW facilities score most highly overall on the chosen decision criteria and that scale is more important than technology design in determining overall EfW policy impact.

The use of materials and the generation of waste are linked to economic activities and in many projections these are assumed to be a constant ratio of the economic activities. This may be the case considering detailed economic activities and unchanged technology. However, the assumption of constant coefficients is questionable when linking material use and waste generation to aggregated economic activities. Therefore, in this paper, econometrics is used to test the assumption of constant waste coefficients empirically. The analyses show that an assumption of constant waste coefficients is not supported, generally, and a model allowing for trendwise changing coefficients is developed and used for projections of waste and material flows in 25 European countries.

The life cycle of basic food items was studied in order to discover the reasons for low landfill diversion rates of this material. Management failures at key points of the cycle were identified. Subjects of study were commercialization procedures of fruit and vegetables before consumption, consumption proper and after-consumption disposal procedures for food scraps in the Brazilian context. Before consumption, the rate of lost fruit and vegetables stood at 16 wt.% of the total quantity commercialized. During consumption by residents, the waste rate of food amounted to 9 wt.% of all collected household garbage. In the after-consumption sector of the cycle, biodegradables represented 72 wt.% of all household garbage collected by official means in a typical Brazilian town. The numbers produced clearly identified landfill diversion of biodegradables as a management problem. The authors experimented with original proactive administrative procedures designed to set landfill diversion targets. The occurrence of wasted fruit and vegetables at the wholesaler and retailer levels was identified. Remedies were proposed and tested to reduce this waste by at least 50%. In the after-consumption sector, the notion of divided garbage collection was developed and applied to test communities. It was shown that biodegradables may be collected separately from the rest of household waste. This resulted in a diversion potential of 100% for biodegradables alone and 77 wt.% for all collected household waste. The study produced a formal policy proposal to municipal administrations to avoid the need for tipping of biodegradable material.

The detailed characterization of household waste in the city of Uberlândia, Central Brazil, reveals the presence of 72 weight percent biodegradable organic matter. For the first time, this research contributes data on Uberlândia to national statistics. A new concept of reporting household waste composition was employed. The effect of informal collection was considered. A better estimate of the true generation rate of household waste in this country resulted. Technical and administrative shortcomings of the present models for household waste management were identified. In order to correct them, the philosophy of divided collection was developed, and the corresponding management model is detailed. The model was applied to a test community. Experiments were conducted with behavior management of people and with collection and sorting of waste. The model was deemed functional. It opens the prospect of diverting 84% of waste from landfill.

This paper evaluates the two well-known final waste disposal methods, incineration and landfilling. In particular we compare the social cost of two best-available technologies using a point estimate based on private and environmental cost data for the Netherlands. Not only does our comparison allow for Waste-to-Energy incineration plants but for landfills as well. The data provide support for the widespread policy preference for incineration over landfilling only if the analysis is restricted to environmental costs alone and includes savings of both energy and material recovery. Gross private costs, however, are so much higher for incineration, that landfilling is the social cost minimizing option at the margin even in a densely populated country such as the Netherlands. Furthermore, we show that our result generalizes to other European countries and probably to the USA. Implications for waste policy are discussed as well. Proper treatment of and energy recovery from landfills seem to be the most important targets for waste policy. Finally, WTE plants are a very expensive way to save on climate change emissions.