RESUMEN
Waste-sector greenhouse gas emissions have long been accepted as a critical component of climate change mitigation efforts because of the significant radiative forcing of methane (CH4) production from municipal landfills and other emissions from waste management processes. In developed countries, waste generation is expected to peak and decline by the end of the century, whereas waste generation is rapidly rising in many developing nations. The extent to which the countries of the world are planning to handle future quantities of waste has not been explored in detail. This work provides the first detailed account of future waste management planning and waste-sector mitigation strategies through an analysis of stated commitments in the 174 Nationally Determined Contributions (NDCs, documents outlining each country's actions to mitigate carbon emissions and adapt to a changing climate) that have been filed to date within the Framework Convention on Climate Change secretariat in Bonn. One-hundred thirty-seven of 174 countries that submitted NDCs included waste-sector emission mitigation actions, representing approximately 85% of all global emissions. About half (67) of the countries that included waste sector mitigation tactics identified infrastructure or policy actions to meet mitigation commitments, but these strategies vary widely in their scope and level of detail. Landfilling was the most commonly-cited waste-sector commitment (nâ¯=â¯47), followed by deriving energy from waste through various techniques (nâ¯=â¯42). Countries targeting improved solid waste collections had less extensive coverage (µcollectionâ¯=â¯38% of generated waste collected) than countries that did not prioritize improved collections (µcollectionâ¯=â¯46% of waste generation), but countries not prioritizing the waste sector at all in NDCs had the most limited waste collection coverage (µcollectionâ¯=â¯33%). Almost all of the countries that specified emissions inventory assumptions (132 of 135) use outdated CH4 global warming potential values which, coupled with missing or poor waste management data suggests many countries may be underestimating the importance of waste sector emissions in national emissions portfolios. Several examples of data collection and reporting models are identified that can help to inform and potentially improve life-cycle environmental outcomes in the waste sector. Adaptation strategies detailed in NDCs have largely overlooked the waste sector, suggesting inadequate incorporation of future climate scenarios in waste sector infrastructure planning.
Asunto(s)
Eliminación de Residuos , Administración de Residuos , Efecto Invernadero , Residuos Sólidos , Instalaciones de Eliminación de ResiduosRESUMEN
Using nonhazardous wastes as inputs to production creates environmental benefits by avoiding disposal impacts, mitigating manufacturing impacts, and conserving virgin resources. China has incentivized reuse since the 1980s through the "Comprehensive Utilization of Resources (CUR)" policy. To test whether and to what extent environmental benefits are generated, 862 instances in Jiangsu, China are analyzed, representing eight industrial sectors and 25 products that qualified for tax relief through CUR. Benefits are determined by comparing life cycle inventories for the same product from baseline and CUR-certified production, adjusted for any difference in the use phase. More than 50 million tonnes of solid wastes were reused, equivalent to 51% of the provincial industrial total. Benefits included reduction of 161 petajoules of energy, 23 million tonnes of CO2 equivalent, 75 000 tonnes of SO2 equivalent, 33 000 tonnes of NOX, and 28 000 tonnes of PM10 equivalent, which were 2.5%-7.3% of the provincial industrial consumption and emissions. The benefits vary substantially across industries, among products within the same industry, and when comparing alternative reuse processes for the same waste. This first assessment of CUR results shows that CUR has established a firm foundation for a circular economy, but also suggest additional opportunities to refine incentives under CUR to increase environmental gain.
Asunto(s)
Ambiente , Industrias/métodos , Residuos , China , Política Ambiental , Industrias/estadística & datos numéricos , Reciclaje , Residuos Sólidos , Residuos/estadística & datos numéricosRESUMEN
This study advances contemporary ideas promoting the importance of managing wastes as resources such as closed-loop or circular material economies, and sustainable materials management by reinforcing the notion of a resource-based paradigm rather than a waste-based one. It features the creation of a quantitative tool, the "reuse potential indicator" to specify how "resource-like" versus how "waste-like" specific materials are on a continuum. Even with increasing attention to waste reuse and resource conservation, constant changes in product composition and complexity have left material managers without adequate guidance to make decisions about what is technically feasible to recover from the discard stream even before markets can be considered. The reuse potential indicator is developed to aid management decision-making about waste based not on perception but more objectively on the technical ability of the materials to be reused in commerce. This new indicator is based on the extent of technological innovation and commercial application of actual reuse approaches identified and cataloged. Coal combustion by-products (CCBs) provide the test case for calculating the reuse potential indicator. While CCBs are often perceived as wastes and then isolated in landfills or surface impoundments, there is also a century-long history in the industry of developing technologies to reuse CCBs. The recent statistics show that most CCBs generated in Europe and Japan are reused (90-95%), but only 40-45% of CCBs are used in the United States. According to the reuse potential calculation, however, CCBs in the United States have high technical reusability. Of the four CCBs examined under three different regulatory schemes, reuse potential for boiler slag and flue-gas desulfurization gypsum maintains a value greater than 0.8 on a 0-1 scale, indicating they are at least 80% resource-like. Under current regulation in the United States, both fly ash and bottom ash are 80-90% resource-like. Very strict regulation would remove many reuse options decreasing potential for these two CCBs to 30% resource-like. A more holistic view of waste and broad application of the new indicator would make clear what technologies are available and assist public and private decision makers in setting quantitative material reuse targets from a new knowledge base that reinforces a resource-based paradigm.
Asunto(s)
Conservación de los Recursos Naturales , Reciclaje , Administración de Residuos/métodos , Ceniza del Carbón , Residuos Industriales , Estados UnidosRESUMEN
Local reuse of waste materials from industrial processes has many potential environmental benefits, but these have been difficult to aggregate and measure across industries on a broad geographic scale. Nonhazardous industrial waste is a high volume flow principally constituted of wastewater with some solid materials. The state of Pennsylvania produced some 20 million metric tons of these residual wastes in 2004. An innovative reporting requirement for industrial generators implemented and compiled by the Pennsylvania Department of Environmental Protection has resulted in a rich database collected since 1992 of residual waste generation, detailing the fate of more than 100 materials. By combining these records with life cycle inventory (LCI) data, the current and potential environmental benefits of residual waste use have been assessed. Results for Pennsylvania indicate a savings in 2004 of 13 PJ of primary energy, 0.9 million metric tons of CO2eq, 4300 tons of SO2eq, and 4200 tons of NOx emissions from reuse of residual wastes. While these energy savings constitute less than 1% of total industrial primary energy use in the state, it is a greater quantity of energy than that generated by the state's renewable energy sector. The framework and constraints surrounding reuse of residualwaste in Pennsylvania are discussed.
Asunto(s)
Conservación de los Recursos Naturales , Residuos Industriales , PennsylvaniaRESUMEN
Resource sharing among co-located firms--referenced in the industrial ecology literature as "industrial symbiosis"--engages traditionally separate industries in a collective approach to business and environmental management involving the physical exchanges of materials, energy, water, and byproducts. While industrial symbiosis is seen hypothetically as a win-win situation, there are few analyses of the economic and environmental consequences for the individual participants in multi-faceted exchanges. In this article, the nascent industrial symbiosis network in Guayama, Puerto Rico, is explored from environmental, economic, and regulatory perspectives of the individual participants and the community. A coal-fired power plant, owned and operated by the AES Corporation, draws five million gallons per day of process water from nearby sources thus avoiding freshwater withdrawals and, through steam sales, significantly reduces emissions from a nearby refinery. This article quantifies economic and environmental costs and benefits for the symbiosis participants, concluding that there are substantial benefits to engaging in symbiosis, although these benefits fall unevenly on participating organizations. Policy intervention can be a viable means of motivating more regular occurrences of resource exchanges among groups of firms.