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By means of the life cycle assessment methodology, the purpose of this study is to assess the environmental impact when biomethane from organic waste produced at residential level is used to supply energy to a group of dwellings in the distributed generation paradigm. Three different Combined Heat and Power systems, such as fuel cells, Stirling engine and micro gas turbine, installed at household level are assessed in two different settings: one in Northern Europe (UK) and one in Southern Europe (Italy). Different operating strategies are investigated for each technology. Moreover, marginal electricity production technologies are analysed to assess their influence on the results. This study has demonstrated that the type of bio-methane fed micro-CHP technology employed has a significantly different environmental impact: fuel cells are the most environmentally friendly solution in every category analysed; Stirling engines, although can supply heat to the largest number of dwellings are the least environmentally friendly technology. However, key factors investigated in the model presented in this paper influence the decision making on the type of technology adopted and the operating strategy to be implemented. [ABSTRACT FROM AUTHOR]

The life cycle approach is used to explore the links between environmental impact and added economic value within the supply chain.

Abstract: Phosphorus is an abundant resource, even though the most economically attractive reserves are geographically concentrated, so that whether and when production will peak are highly uncertain. However, analysis of the global use of phosphorus primarily in agriculture (including animal husbandry), reveals an exceptionally “leaky” supply chain: losses, including leaching from soils and animal excreta, amount to some 90% of the inputs. The potential for innovation to improve the efficiency of phosphorus use is therefore enormous, going beyond recovery of phosphorus from waste water to reducing the losses from the whole use system. Drivers to improve the system efficacy include the concerns over distribution and possibly security of supply and also the environmental impacts of phosphorus emissions. Future production, use and price of phosphorus therefore depend as much on changes in food consumption and agricultural practices as on changes in mining and processing. [Copyright &y& Elsevier]

Abstract: Although new paint products and technologies have been developed, the sector of paint application still contributes substantially to total volatile organic compound (VOC) emissions. Recent environmental legislation, especially the EU Solvent Emission Directive 1999/13/EC and its transposition into national law, coming into force in 2007, will have an important influence on the sector structure and the associated supply chain, especially for small- and medium-sized enterprises (SMEs). This paper summarises a comprehensive scenario analysis to explore possible future trajectories for the sector. The main focus is on paint application activities, considering in particular the consequences of new environmentally friendly products and technologies which can be used by SMEs. Four different scenarios representing possible future states of the sector are evaluated, taking into account environmental, technical and socio-economic aspects along the associated supply chain and life cycle. The scenarios allow the formulation of recommendations and guidelines for policy makers and industries. This example confirms that interdisciplinary scenario analysis is a suitable approach to investigate possible future development of an industrial sector. [Copyright &y& Elsevier]

Abstract: It is the stated policy of the UK government to reduce emissions of carbon dioxide by 60% by 2050. This policy, which goes far beyond commitments under the Kyoto agreement, was originally advocated by the Royal Commission on Environmental Pollution, of which the author was a member. Its acceptance was seen by many as a surprising development, possibly reflecting the strength of the underlying case. The target was developed by a three-legged argument which reflects the three components of sustainability: Environmental constraints: limits on emissions to avoid risk of major climate change; Social equity: equal per-capita allocation of emissions; Techno-economic: the feasibility and cost of reduction on this scale. Assessment of techno-economic feasibility shows that the target can be achieved economically if the efficiency of energy use is improved to achieve reduction in demand, combined with a shift to lower-carbon energy sources. The greatest scope for demand reduction lies in improving the building stock, combined with providing low-grade heat from sources such as biomass. On the supply side, the principle questions are how much controllable electricity generation is needed, and whether this capacity should be nuclear or fired by fossil fuels with the carbon dioxide formed sequestered in geological strata. Increased use of biomass is a key part of the shift to a lower carbon economy; the barriers which have retarded the development of biomass in the UK are explored. [Copyright &y& Elsevier]

Abstract: Sustainable development presents us all with the challenge of living in ways which are compatible with the long-term constraints imposed by the finite carrying capacity of the closed system which is Planet Earth. The chemical engineering approach to the management of complex systems involving material and energy flows will be essential in meeting the challenge. System-based tools for environmental management already embody chemical engineering principles, albeit applied to broader systems than those which chemical engineering conventionally covers. Clean technology is an approach to process selection, design and operation which combines conventional chemical engineering with some of these system-based environmental management tools; it represents an interesting new direction in the application of chemical engineering to develop more sustainable processes. Less conventional applications of chemical engineering lie in public sector decisions, using the approach known as post-normal science. These applications require chemical engineers to take on a significantly different role, using their professional expertise to work with people from other disciplines and with the lay public. The contribution of chemical engineering to the formation of UK energy policy provides an example of the importance of this role. Recognising the role of engineers as agents of social change implies the need for a different set of skills, which just might make the profession more attractive to potential new recruits. [Copyright &y& Elsevier]

This paper provides an example of the kind of analysis needed to support better targeted policies to reduce the environmental impacts of agricultural activities, using the specific case of Anaerobic Digestion (AD) to treat animal manure and other agricultural and food wastes in British Columbia (BC). Economic and life cycle environmental performance metrics are estimated to compare integrated and stand-alone systems using the resulting biogas and digestate. Using biogas for heating outperforms purifying it for distribution as renewable natural gas (RNG). However, current policy and energy prices in BC perversely support RNG, making biogas-fired heating systems economically unattractive. The performance of biogas-fired heating system can be improved and their dependence on subsidies reduced by integration with local agricultural activities, exploiting CO 2 and digestate as by-products. Biogenic CO 2 , from combustion of the biogas and from mushroom cultivation, can displace natural gas use in producing CO 2 -enriched atmospheres to enhance growth rates in greenhouse production. Using digestate as growing media in greenhouses and mushroom cultivation can generate significant revenues but the environmental benefits are nugatory. Co-digestion of food waste can further improve performance by increasing biogas yield. With all extra benefits combined, integrated AD systems can increase both GHG mitigation and revenues by at least 80%. The analysis illustrates the general point that, to avoid perverse outcomes, policy measures must support options based on their actual GHG mitigation benefits, rather than targetting any specific technology. Image 1 • Biogas heating has higher GHG mitigation at lower cost than CHP or RNG. • Stand-alone biogas options require financial support from policy measures in BC. • Integrating AD into a broader system achieves further GHG and economic benefits. • Policy measures need to be supported by such systematic analyses. Integration of anaerobic digestion with agricultural activities can further reduce energy and material consumption and achieve substantial environmental and economic benefits from stand-alone biogas options. [ABSTRACT FROM AUTHOR]

Improving economic competitiveness is the key for sustainable development of the wood pellet industry. To support this development, we have carried out a comprehensive techno-economic evaluation of five possible process configurations for production of conventional (CWP) and torrefied (TWP) wood pellets in the Canadian province of British Columbia (BC), based on process simulation with multi-scale models involved as illustrated in the graphical abstract. A novel heat integration strategy is proposed for the TWP production process to avoid the use of N 2 and achieve auto-thermal operation. In comparison with CWPs, producing TWPs in the operating sequence drying, torrefaction, grinding, pelletization can reduce production costs by about 10% and reduce delivered costs to both domestic and overseas markets by about 20%. It is essential that the TWP plant is located in a region with abundant and low-cost feedstock, low electricity price, low labor cost, and efficient distribution logistics. Due to the low capital cost contribution (10%), torrefaction could be implemented by either building a new plant or upgrading an existing conventional pellet plant. The market analysis reveals that the future market for TWPs from BC is expected to lie outside Canada, in the Asia Pacific region, and Europe, unless significant domestic policy measures are introduced to promote Canadian use of TWPs. • Torrefied wood pellets (TWP) costs 20% less than conventional pellets over supply chains. • BC pellets are expected to lie outside Canada, especially in the Asia Pacific region. • The best pathway to produce TWPs is drying- > torrefaction > grinding- > pelletization. • TWPs can be produced auto-thermally without N 2 and catalyst. • The critical production costs for TWPs are raw material, electricity, and labor. [ABSTRACT FROM AUTHOR]

• Torrefied wood pellets have better performances than conventional pellets. • Replacing coal with BC torrefied pellets reduces GHG emissions by at least 85%. • GHG reductions are greatest when BC pellets are used overseas. • The most efficient processing sequence is drying-torrefaction-grinding-pelleting. • In addition to carbon tax, other mechanisms are needed to support pellet industry. With increasing international trade in wood pellets for use as fuel, the carbon footprint over the supply chain is of growing concern. The Canadian province of British Columbia (BC) is endowed with clean electricity and rich biomass resources, which are essential for developing a low-carbon wood pellet industry. This work aims to quantify the life cycle Greenhouse Gas (GHG) emissions of torrefied wood pellets in comparison with conventional pellets, derived from forest residues in BC and transported to replace coal at power plants in Europe, the Asia Pacific region and elsewhere in Canada. The GHG reduction costs in different markets are also quantified. Five possible production configurations are analysed with uncertainties taken into consideration. Torrefied wood pellets are found to have better environmental performance than conventional pellets. The best production process, which follows the sequence drying-torrefaction-grinding-pelletization, can reduce primary energy consumption and carbon footprint by about 30% compared to conventional pellets. Over the life cycle, transportation contributes most GHG emissions (>50%), while electricity use, including sawmilling and pellet production, represents the greatest energy consumption (~50%). Life cycle analysis reveals that GHG emissions from the supply chain offset at most 15% of the savings from using BC torrefied wood pellets to replace coal. GHG reductions are greatest when the pellets are used in overseas markets, especially the Asia Pacific region and the EU, rather than domestic Canadian markets. The current carbon taxation level cannot cover the abatement cost of BC pellets; other mechanisms are still needed to support the sustainable development of the industry. [ABSTRACT FROM AUTHOR]

• Radiological impacts, especially from nuclear wastes, are often disregarded in LCA. • A novel framework and two methodologies are proposed. • UCrad is based on USEtox and Critical Group Methodology on Risk Assessment. • Characterisation factors are in agreement with Human Health Damages methodology. • Ke step towards incorporating ionising radiation impacts in LCA. To date, impacts of ionising radiations have been largely disregarded in Life Cycle Assessment (LCA). This omission can be linked to the lack of a standard and comprehensive framework for including the effects of radionuclides alongside other emissions from industrial processes. Drawing on a recent review of Radiological Impact Assessment methodologies for LCA studies, this article proposes an overarching framework for integrating impacts of radionuclides in the Impact Assessment phase of LCA. From this framework, two alternative methodologies have been derived. They differ mainly in the way transport and dispersion of radionuclides in the environment are modelled: UCrad represents the first-of-its-kind compartment-type methodology for radionuclides, whereas the alternative Critical Group Methodology (CGM) has been adapted from standard Risk Assessment practices. Characterisation factors for a range of emitted species have been calculated using both methodologies and compared with those obtained from the Human Health Damages methodology, which is the only approach to radiological impacts yet implemented in LCA. For both UCrad and CGM the results are in general agreement with the Human Health Damages methodology, but UCrad gives factors closer to those obtained by the CGM approach. UCrad represents a major step towards incorporating ionising radiation impacts in LCIA. A subsequent paper will explore quantitatively the main differences between the UCrad and CGM methodologies. [ABSTRACT FROM AUTHOR]

• Two methodologies for radiological impacts were proposed in a complementary article. • Here, characterisation factors are compared quantitatively and in detail. • Deviations are meaningful and explainable by the different fate models. • A practical rule for the applications of these methodologies is proposed. In a complementary article, an overarching framework was proposed to include radiological impacts in Life Cycle Impact Assessment (LCIA). Two methodologies were derived embodying the framework: the Critical Group Methodology (CGM), adapted from the approach commonly used in Human and Environmental Risk Assessment (HERA), and UCrad, based on the compartment modelling approach commonly used in LCIA. In this paper, characterisation factors obtained by the two methodologies are compared in detail to investigate the consequences of the different approaches to fate modelling and the sensitivity of the characterisation factors to the radionuclides' half-life. Characterisation factors from the CGM methodology are strongly affected by radioactive decay at low half-life and by dilution at large distances. Conversely, UCrad factors are not affected by dilution and are affected less than CGM by radioactive decay. It is concluded that UCrad is more appropriate than CGM for LCA because it is consistent with the general approach used in LCIA. However, CGM can be used alongside UCrad to make recommendations on the location and scale of specific processes emitting radionuclides. [ABSTRACT FROM AUTHOR]

This research compares and contrasts the physical and chemical characteristics of incinerator sewage sludge ash (ISSA) and pyrolysis sewage sludge char (PSSC) for the purposes of recovering phosphorus as a P-rich fertiliser. Interest in P recovery from PSSC is likely to increase as pyrolysis is becoming viewed as a more economical method of sewage sludge thermal treatment compared to incineration. The P contents of ISSA and PSSC are 7.2–7.5% and 5.6%, respectively. Relative to the sludge, P concentrations are increased about 8-fold in ISSA, compared to roughly 3-fold in PSSC. Both PSSC and ISSA contain whitlockite, an unusual form of calcium phosphate, with PSSC containing more whitlockite than ISSA. Acid leaching experiments indicate that a liquid/solid ratio of 10 with 30 min contact time is optimal to release PO 4 -P into leachate for both ISSA and PSSC. The proportion of P extracted from PSSC is higher due to its higher whitlockite content. Heavy metals are less soluble from PSSC because they are more strongly incorporated in the particles. The results suggest there is potential for the development of a process to recover P from PSSC. [ABSTRACT FROM AUTHOR]

Activated carbons have excellent performance in a number of process applications. In particular, they appear to have the most favourable characteristics for adsorption processes, thanks to their high porosity and large surface area. However, a comprehensive assessment of the environmental impacts of their manufacturing chain is still lacking. This study evaluates these impacts taking the specific case of activated carbon produced from coconut shells in Indonesia, which is the major coconut producer county. Coconut shells as raw materials are utilized for activated carbon production due to their abundant supply, high density and purity, and because they seem to have a clear environmental advantage over coal-based carbons, particularly in terms of acidification potential, non-renewable energy demand and carbon footprint. Life Cycle Assessment and process analysis are used to quantify all the environmental interactions over the stages of the life cycle of an activated carbon manufacturing chain, in terms of inputs of energy and natural resources and of outputs of emissions to the different environmental compartments. Estimates for the environmental burdens over the life cycle have been obtained by developing mass and energy balances for each of the process units in the production chain. The results indicate the operations with the greatest effects on the environmental performance of activated carbon production and hence where improvements are necessary. In particular, using electrical energy produced from renewable sources, such as biomass, would reduce the contributions to human toxicity (by up to 60%) and global warming (by up to 80%). Moreover, when the material is transported for processing in a country with a low-carbon electricity system, the potential human toxicity and global warming impacts can be reduced by as much as 90% and 60% respectively. [ABSTRACT FROM AUTHOR]

This work aims to provide a comprehensive in-depth analysis of the life cycle environmental and economic performance of some key global supply chains for torrefied wood pellets (TWP) used as bulk fuel, including their contribution to the bio-economy of the region where they are produced, and the effects of carbon accounting and carbon tax policies on the TWP trade. TWPs produced in British Columbia (BC), the western-most province of Canada, are taken as a specific example, with the results compared with pellets produced in other Canadian provinces, Southeast US and Vietnam. It is found that BC has comparative advantages in TWP production, benefiting from abundant biomass resources, availability of low-carbon electricity, existence of a well-developed forest product industry, and accessibility to international markets. The suitability of different domestic and overseas markets is assessed. In Canada, there is great potential demand for BC TWPs in the provinces of Alberta and Saskatchewan. In the Asia-Pacific region and Europe, BC pellets are not cost-competitive compared with pellets from Vietnam and Southeast US, due to higher production costs arising in part from BC's high carbon tax. However, BC producers have supply advantages over producers in Vietnam and the Southeast US in the province's abundant biomass and clean electricity supply. Transforming production from conventional to torrefied pellets can increase the contribution of the industry to the regional economy. The carbon accounting and carbon tax policies in different countries/regions will impact the TWP trade, and merit further study. • Several key global torrefied wood pellet (TWP) supply chains are compared. • BC has comparative advantages in TWP production compared with other Canadian provinces. • The domestic overseas markets of BC TWPs are identified. • The contributions of TWP to the regional bio-economy are identified. • The effects of carbon accounting and carbon tax policies on TWP trade are discussed. [ABSTRACT FROM AUTHOR]

In the past, almost all residual municipal waste in the UK was landfilled without treatment. Recent European waste management directives have promoted the uptake of more sustainable treatment technologies, especially for biodegradable waste. Local authorities have started considering other options for dealing with residual waste. In this study, a life cycle assessment of a future 20 MWe plant using an advanced two-stage gasification and plasma technology is undertaken. This plant can thermally treat waste feedstocks with different composition and heating value to produce electricity, steam and a vitrified product. The objective of the study is to analyse the environmental impacts of the process when fed with seven different feedstocks (including municipal solid waste, solid refuse fuel, reuse-derived fuel, wood biomass and commercial & industrial waste) and identify the process steps which contribute more to the environmental burden. A scenario analysis on key processes, such as oxygen production technology, metal recovery and the appropriate choice for the secondary market aggregate material, is performed. The influence of accounting for the biogenic carbon content in the waste from the calculations of the global warming potential is also shown. Results show that the treatment of the refuse-derived fuel has the lowest impact in terms of both global warming potential and acidification potential because of its high heating value. For all the other impact categories analysed, the two-stage gasification and plasma process shows a negative impact for all the waste streams considered, mainly due to the avoided burdens associated with the production of electricity from the plant. The plasma convertor, key characteristic of the thermal process investigated, although utilising electricity shows a relatively small contribution to the overall environmental impact of the plant. The results do not significantly vary in the scenario analysis. Accounting for biogenic carbon enhanced the performance of biomass and refuse-derived fuel in terms of global warming potential. The main analysis of this study has been performed from a waste management perspective, using 1 ton of waste as functional unit. A comparison of the results when 1 kWhe of electricity produced is used as functional unit shows similar trends for the environmental impact categories considered. [ABSTRACT FROM AUTHOR]

The EU landfill and Waste Framework directives are driving new approaches to waste management in the UK, away from landfilling and mass-burn incineration, which has been regarded as the main alternative to landfilling. The objective of this study is to compare the environmental impacts of three dual-stage advanced energy-from-waste technologies, i.e. gasification and plasma gas cleaning, fast pyrolysis and combustion and gasification with syngas combustion, with those associated with conventional treatments for municipal solid waste, i.e. landfill with electricity production and incineration with electricity production. Results show that the two-stage gasification and plasma process has a significantly better overall environmental performance than the conventional waste treatment technologies and somewhat better than a more modern incineration plant, exemplified by a plant under commissioning in Lincolnshire in the UK. The benefits of the gasification and plasma process arise primarily from its higher net electrical efficiency. [ABSTRACT FROM AUTHOR]

This study investigates the potential integration of a dairy farm and a greenhouse into an eco-industrial system to promote waste-to-energy and waste-to-material exchanges. Natural gas consumption is substituted by renewable biogas generated from anaerobic digestion (AD) of the dairy manure; CO2 for plant enrichment in greenhouses is supplied by biogas combustion and the digestate (digestion residue) from digesters is used as animal bedding, plant growing media and liquid fertilizers. A life cycle analysis (LCA) was conducted to quantify the environmental impacts of the eco-industrial system in comparison to the conventional agriculture practices. The results show that the integrated system reduces non-renewable energy consumption, climate change impact, acidification, respiratory effects from organic emissions, and human toxicity by more than 40%. If the digestate surplus is treated as a waste, the integrated system shows an increase in eutrophication and respiratory effects from inorganic emissions while all the analyzed impacts are reduced if the digestate can be used for substituting chemical fertilizers. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the anticipated environmental benefits from integrating a dairy farm and a greenhouse; the integration is based on anaerobic digestion of manures to produce biogas energy, biogenic CO 2 , and digested slurry. A full Life Cycle Assessment (LCA) has been conducted on six modeled cases applicable in British Columbia, to evaluate non-renewable energy consumption, climate change, acidification, eutrophication, respiratory effects and human toxicity. Compared to conventional practice, an integrated system has the potential to nearly halve eutrophication and respiratory effects caused by inorganic emissions and to reduce non-renewable energy consumption, climate change, and acidification by 65–90%, while respiratory effects caused by organic emissions become negative as co-products substitute for other materials. Co-digestion of other livestock manures, greenhouse plant waste, or food and food processing waste with dairy manure can further improve the performance of the integrated system. [ABSTRACT FROM AUTHOR]

Abstract: The environmental impact of different land-use systems for energy, up to the farm or forest “gate”, has been quantified with Life Cycle Assessment (LCA). Four representative crops are considered: OilSeed Rape (OSR), Miscanthus, Short-Rotation Coppice (SRC) willow and forest residues. The focus of the LCA is on changes in Soil Organic Carbon (SOC) but energy use, emissions of GreenHouse Gases (GHGs), acidification and eutrophication are also considered. In addition to providing an indicator of soil quality, changes in SOC are shown to have a dominant effect on total GHG emissions. Miscanthus is the best land-use option for GHG emissions and soil quality as it sequesters C at a higher rate than the other crops, but this has to be weighed against other environmental impacts where Miscanthus performs worse, such as acidification and eutrophication. OSR shows the worst performance across all categories. Because forest residues are treated as a by-product, their environmental impacts are small in all categories. The analysis highlights the need for detailed site-specific modelling of SOC changes, and for consequential LCAs of the whole fuel cycle including transport and use. [Copyright &y& Elsevier]

To achieve more than incremental reductions in resource consumption and waste, it will be necessary to develop new approaches to the systematic use and re-use of materials in the kind of system termed an “industrial ecology”. This paper presents a new methodology—CHAin Management of Materials and Products (CHAMP)—developed for modelling the flow of materials through a succession of uses with different performance requirements. Although developed specifically for polymers, the CHAMP approach is also applicable to other materials and products. Materials are characterised by a set of technical performance parameters, termed utilities. Geographical location is also treated as a utility to enable logistics—both distribution of products and collection of used products or waste—to be incorporated within the same modelling framework. Processing, transport and use are treated as activities through which a material can pass. The costs and environmental impacts of activities are included in the modelling framework, and are assessed on a life cycle basis by considering the complete supply chain of materials and energy used by each activity. The methodology includes acceptance criteria which determine whether a material is suitable for specific uses or activities. These criteria are applied within the model to guide selection of materials for specific applications and of successive uses for specific materials. A simple example of the CHAMP approach is given, to illustrate the kinds of problem to which it has been applied. [Copyright &y& Elsevier]

The earlier in the development of a process a design change is made, the lower the cost and the higher the impact on the final performance. This applies equally to environmental and technical performance, but in practice the environmental aspects often receive less attention. To maximise sustainability, it is important to review all of these aspects through each stage, not just after the design. Tools that integrate environmental goals into the design process would enable the design of more environmentally friendly processes at a lower cost. This paper brings together approaches based on Life Cycle Assessment (LCA) including comparisons of design changes, hotspot analysis, identification of key impact categories, environmental break-even analysis, and decision analysis using ternary diagrams that give detailed guidance for design while not requiring high quality data. The tools include hotspot analysis to reveal which unit operations dominate the impacts and therefore should be the focus of further detailed process development. This approach enables the best variants to be identified so that the basic design can be improved to reduce all significant environmental impacts. The tools are illustrated by a case study on the development of a novel process with several variants: thermal cracking of mixed plastic waste to produce a heavy hydrocarbon product that can displace crude oil, naphtha, or refinery wax or be used as a fuel. The results justified continuing with the development by confirming that the novel process is likely to be a better environmental option than landfill or incineration. The general approach embodied in the toolkit should be applicable in the development of any new process, particularly one producing multiple products. [ABSTRACT FROM AUTHOR]

Every year in Europe refrigerant gases with a greenhouse-warming equivalent of more than 30 Mt CO 2 are emitted from retail refrigerators. Furthermore, the effective efficiency of such refrigerators is far below that achievable under ideal (e.g. optimal-load; minimum access) operation. In this work the design of an alternative on-demand cooling unit is presented. The unit is based on the cooling effect provided by desorption of carbon dioxide previously adsorbed onto a bed of graphite-bonded activated carbon: in this paper, a case study of a self-chilling beverage can is used to demonstrate the technology. The high compaction of the activated carbon, and the presence of graphite, enhances the heat transfer properties of the adsorbent, thus enhancing the efficiency of cooling. Furthermore, potential exists for the use of activated carbon and CO 2 from waste sources. This paper provides an overview of the design basis and environmental advantages of the unit, and experimental and simulation studies on the thermal dynamics of the cooling process. Particular attention is given to the effective thermal conductivity of the activated carbon bed. The results indicate that adequate on-demand cooling can be achieved within a portable unit. However, scope exists for enhancing the heat transfer within the cooling chamber through design and bed composition alterations. Recommendations for improved unit design are presented. [ABSTRACT FROM AUTHOR]

The chill-on-demand system is a new technology designed to provide cooled products on demand, thereby avoiding chilled storage. It uses the cooling effect provided by endothermic desorption of carbon dioxide previously adsorbed onto a bed of activated carbon and has the potential to be applied to any type of product that needs to be cold at the point of consumption. The principles of life cycle engineering have been utilized to evaluate the overall environmental performance of one possible application of this technology: a self-chilling beverage can, with a steel outer can to contain the beverage and an inner aluminium can to contain the adsorbent. An attributional life cycle assessment has been undertaken considering all the life cycle stages of a self-chilling can: manufacture of each part of the beverage container, its utilization, collection of the used can, and management of the waste by reuse, recycling and landfilling. Activated carbon production is included in detail, to assess its contribution to the overall life cycle. The results are compared with those for conventional aluminium and steel beverage cans stored in two types of retail chiller: a single door refrigerator and a large open-front cooler. A sensitivity analysis explores alternative scenarios for activated carbon production and for recovery of the can components post-use for reuse or recycling. The results highlight the importance of using activated carbon produced from biomass by a process with efficient use of low-carbon electrical energy, energy recovery from waste streams and appropriate air pollution control, and of achieving high rates of recovery, re-use and recycling of the cans after use. The results suggest limited markets into which the product might be introduced, particularly where it would displace inefficient chilled storage in an electricity system with a high proportion of coal-fired generation. [ABSTRACT FROM AUTHOR]

Highlights: [•] We investigated the environmental impact of treatment of OFMSW in London. [•] We performed LCA with sensitivity analysis to test the robustness of the model. [•] We found AD is the best option for some impact categories, but not for all. [•] The most important assumption results quantity and quality of energy substituted. [ABSTRACT FROM AUTHOR]

Symbiotic integration of agricultural activities is widespread but quantitative assessments of the environmental benefits are scarce. To explore the potential benefits of applying the industrial symbiosis approach in agriculture and horticulture, a detailed case study is reported of a potential Eco-Industrial Park (EIP) including three activities: dairy farming, greenhouse cultivation of vegetables, and mushroom growing. These activities are widespread world-wide but, to enable quantitative assessment, the specific EIP studied is located in the Canadian province of British Columbia (BC). The activities are linked by anaerobic digestion of dairy manure to produce biogas and digestate. Biogas replaces natural gas to supply heat to the farms and carbon dioxide (CO 2) to the greenhouse. Digestate is separated into a liquid fertilizer and a solid substrate; the former replaces chemical fertilizers and the latter can be utilized as cow bedding and growing medium for plants and mushrooms. Mushroom growing emits CO 2 which is conventionally ventilated but can be used for stimulating plant growth in the greenhouse. Life Cycle Assessment (LCA) is used to quantify the environmental benefits of the EIP compared to conventional independent farms. Non-renewable energy consumption, greenhouse gas emissions, aquatic acidification, respiratory effects from organic emissions, and human toxicity can be reduced by 50%–90% and aquatic eutrophication and respiratory effects from inorganic emissions can be reduced by more than 10%. Such EIPs can also alleviate nutrient management problems in regions with intensive livestock farming. • An LCA model of EIP linking AD of dairy manure, greenhouse and mushroom operations. • Exchange of by-products enhances energy and material self-sufficiency. • Digestate utilisation within the EIP improves nutrient management. • Reductions of ∼60% achievable in non-renewable energy use and global warming potential. • Reductions of 10%–90% achievable across five other life cycle impact categories. [ABSTRACT FROM AUTHOR]