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• Designed an automated Material Recovery Facility for mixed waste. • Estimated a capital cost of $23 MM for 120,000 tonne/year of MSW. • The NPV ranged from $3.57 to $60 MM based on location. • Global warming potentials ranged from 5.98 to 8.53 kg CO 2-eq /MT. Material Recovery Facilities (MRFs) are crucial players in achieving a circular economy. MRFs receive complex waste streams and separate valuable recyclables from these mixtures. This study conducts techno-economic analysis (TEA) to estimate the net present value (NPV) and life cycle assessment (LCA) to estimate different environmental impacts of a commercial scale standalone, single-stream MRF to assess the economic feasibility and environmental impacts of recovering valuable recyclables from an MRF processing 120,000 tonnes per year (t/y). The TEA employs a discounted cash flow rate of return (DCFROR) analysis over a 20-year facility lifetime, along with a sensitivity analysis on the impact of different operating and economic parameters. Results show that the total fixed cost of building the MRF facility is $23 MM, and the operating cost is $45.48/tonne. The NPV of the MRF can vary from $3.57 MM to $60 MM, while 100-year global warming potential can range from 5.98 to 8.53 kg carbon dioxide equivalents (CO2-eq) per tonne of MSW. We have also found that MSW composition (arising from regional effects) significantly impacts costs, 100-year global warming potential, and other impact categories such as acidification potential, eutrophication potential, ecotoxicity, ozone depletion, photochemical oxidation, carcinogenic effects, and non-carcinogenic effects. Sensitivity and uncertainty analysis indicate that waste composition and market prices significantly impact the profitability of the MRF, and the waste composition mostly impacts global warming potential. Our analysis also indicates that facility capacity, fixed capital cost, and waste tipping fees are vital parameters that affect the economic viability of MRF operations. [ABSTRACT FROM AUTHOR]

As conventional oil production becomes limited, transportation fuels are being produced from other unconventional fossil resources such as oil sands. Oil sands are a combination of clay, sand, water and bitumen. Vast quantities of oil sands resources have been found worldwide. The largest known reservoir of oil sands in the world is located in the province of Alberta (Canada). Several techniques for the extraction of the oil from oil sands have been developed in recent decades. Steam-Assisted Gravity Drainage (SAGD) is the most promising approach for recovering heavy and viscous oil resources. In SAGD, two closely-spaced horizontal wells, one above the other, form a steam-injector and producer pair. The reservoir oil is heated by the injected steam and drains to the producer under the effect of gravity. First aim of this work is an economic optimization and evaluation of an hypothetical industrial scale facility (named LINK), located in Alberta. All data relating to LINK plant have been obtained from a review of the existing literature references or have been assumed. A Discounted Cash Flow Analysis (DCFA) of LINK plant has been performed. Costs of existing projects have been found in literature. The results show that the hypothetical plant LINK is a profitable investment and that the investment cost has a significant effect on the competitiveness of the LINK facility. Second purpose of the present work is an environmental analysis of the LINK plant: in order to evaluate GHG emissions from LINK plant, a LCA analysis has been carried out. The calculated emissions from oil sand production by SAGD technology have been compared with values relating to conventional crude oil pathways and to recovery and extraction of bitumen through surface mining from literature. The comparison demonstrated that SAGD is a promising technology also from an environmental point of view. An economic–environmental model for SAGD technology optimization has been developed. [ABSTRACT FROM AUTHOR]

The Canadian province of British Columbia has large forestry resources and therefore provides an informative example of the potential role of bioenergy in mitigating GHG emissions. Even in biomass-rich British Columbia, forestry resources are only sufficient to meet part of the energy demand. This paper compares different energy conversion routes for forestry waste materials: via hydrothermal liquefaction, thermochemical methanol and bioethanol, renewable natural gas, cogeneration of heat and power, heat-only boilers, and power-only generation. The GHG savings, health impacts, minimum selling prices, and GHG abatement costs for each option are estimated by combining life cycle assessment with a discounted cash flow model. The input-based functional unit of 1 oven-dry tonne biomass provides a better basis for comparing possible uses of finite biomass supply than the commonly-used output-based functional unit of 1 GJ bioenergy. Heat-only boiler for district heating gives the highest GHG reduction of 960 kgCO 2 -eq per oven-dry tonne feedstock, while power-only generation delivers minimal GHG benefit in British Columbia. Heat-only boiler and cogeneration offer the lowest GHG abatement costs (<$-20/tCO 2 -eq), due to lower costs and higher energy conversion efficiencies, and are already economically viable, but will not use all the available resources because health impacts generated by biomass combustion limit their deployment, despite life cycle health benefits for avoiding hazardous emissions from slash burning of forestry waste materials. Refined biofuel options are much less cost-effective (>$50/tCO 2 -eq); further technology improvement and policy support are needed to offset the cost disadvantage. • Comparison based on 1 ODT biomass identifies the most efficient way to utilize this scarce resource. • Producing energy from forestry waste materials can reduce emissions of GHGs and other pollutants. • Biomass-fired heat boiler gives maximum GHG mitigation per ODT feedstock. • Biomass-fired heat boiler and cogeneration are the most cost-effective in GHG mitigation. • Liquid biofuel options cause lower local health impacts but at higher GHG abatement costs. [ABSTRACT FROM AUTHOR]

The increased frequency of hot days due to climate change can potentially impair the environmental and economic performance of pig-fattening farms. Several pig-cooling strategies have been proposed to address these impacts, however their implementation is not always economically viable and the potential environmental-economic trade-offs not well understood. Here, we propose and implement a novel framework for environmental and economic evaluation of pig-cooling strategies in a whole farm context. We also demonstrate through a sensitivity analysis how such models can be integrated with projected climate data to investigate how climate change may affect the assessment of capital investments that are made over significant timescales. We considered two strategies implemented in a pig-fattening farm in south Sweden: pig-cooling with showers and with increased air velocity. Operation of the farm under non-cooling conditions was considered as the baseline system against which the analysis was conducted. We calculated whole-farm annual equivalent values (AEV) with the implementation of each strategy through a discounted cash flow analysis and annualised system environmental impact through a life cycle assessment. Both cooling strategies significantly reduced system environmental impact across all categories except water footprint. Acidification potential was reduced the most, exhibiting a −3.28% reduction with pig showers and −1.51% with increased air velocity. Farm profitability improved by +6.79% with showers and +3.37% with increased air velocity. Ambient temperature increase under non-cooling conditions significantly increased all impact categories with acidification being affected the most (+2.24%), and caused a −4.43% decrease in AEV. Both pig-cooling strategies mitigated these effects on system environmental performance. With increased air velocity we observed a +0.718% increase in acidification, while pig showers were the more resilient option exhibiting a +0.690% increase. The study represents a case-in-point for how to rationalise economically environmental management technologies in pig housing systems based on their cost-effectiveness in mitigating environmental impacts. Image 1 • The environmental and economic impacts of two pig-cooling strategies were evaluated. • We considered pig-cooling with showers and increased air velocity at pig lying area. • Both strategies improved farm environmental performance for AP, EP and NRRU. • Both strategies mitigated heat stress, improved pig welfare and farm profitability. • The strategies mitigated the effects of global warming on pig farm sustainability. [ABSTRACT FROM AUTHOR]

Many emerging technologies and alternative farm management practices have the potential to improve the sustainability of pig production systems. The implementation of such practices is not always economically viable. The goal of this study was to assess the cost-effectiveness of such environmental mitigation strategies in pig systems, using an Environmental Abatement Cost analysis. We considered four pig housing (improved insulation, increased ventilation efficiency, frequent slurry removal, increased slurry dilution) and three manure management related abatement strategies (anaerobic digestion, slurry acidification, slurry separation), implemented as stand-alone and as a set of "pig housing–pig housing" and "pig housing–manure management" combinations. We calculated their annual equivalent value through a discounted cash flow analysis and then their annualised abatement potential through a cradle-to-farm gate life cycle assessment. The baseline system against which the analysis was conducted was a typical Danish pig production system, over a 25-year time horizon. The environmental impact categories considered were Non-Renewable Resource Use (NRRU), Non-Renewable Energy Use (NREU), Global Warming Potential (GWP), Acidification Potential (AP) and Eutrophication Potential (EP). Pig housing–anaerobic digestion combinations were the most cost-effective options for GWP, NRRU and NREU. Their abatement costs ranged from −€0.237 to €0.70 per tonne CO 2 eq., −€0.146 to €0.36 per g Sb eq. and -€1.75−04 to €3.11−04 per GJ abated respectively. Anaerobic digestion was the most cost-effective stand-alone investment for GWP (−€0.206 per tonne CO 2 eq.), NRRU (−€0.0493 per g Sb eq.) and NREU (−€1.00−04 per GJ), and slurry acidification for AP (€303 per tonne SO 2 − eq.) and EP (€1190 per tonne PO 4 3− eq.) mitigation. Overall, measures for mitigation of GWP, NRRU and NREU required higher investments than for AP and EP, but also generated profit. The framework developed in this study can potentially aid decision making in the choice of environmentally and economically sustainable pig system modifications. • We evaluated the cost-effectiveness of pig housing and manure management related environmental impact abatement measures. • On-farm anaerobic digestion was cost-effective in reducing global warming, non-renewable resource and energy use. • Mitigating global warming and abiotic depletion required more expensive investments than acidification and eutrophication. • Combining anaerobic digestion with pig housing measures generated profits while reducing the system environmental impact. [ABSTRACT FROM AUTHOR]

In the natural rubber industry, concentrated latex (CL) holds a prominent position due to its use in manufacturing dipped rubber products (e.g., gloves, condoms, etc.). With no previous studies on the process efficiency at commercial level of CL manufacture, this study aimed at adopting process analyses tools in three CL factories (factory A, B and C) in Sri Lanka in view of improving CL manufacture process in financial and environmental terms. This approach possessed three steps: 1) quantification of resource use, financial losses and global warming potential using material flow analysis (MFA), material flow cost accounting (MFCA) and environmental life cycle assessment (ELCA), 2) identification of key issues and proposing improvement options with help of Pareto and what if analyses, field interviews and literature, and 3) determination of potential improvement and feasibility through re-performing MFA, MFCA and ELCA, and discounted cash flow analysis, greenhouse gas payback time and novel loss reduction efficiency index. On average, the present level of financial loss and global warming potential per 1 MT of rubber input were found to be LKR 9608 and 112.8 kg CO2e, respectively. Installation of an advanced trap tank was proposed to factory A (i.e., option-1) whilst extending sedimentation time (i.e., option-2) and Installing inverters and solar panels (i.e., option-3) were recommended to all factories as improvement options. Combined scenario entailing options 2 and 3 for all factories, was found to be the most applicable in terms of financial returns and environmental benefits. • Monetary losses and environmental impact of Concentrated Latex manufacture quantified. • Factors affecting monetary losses and environmental impact identified. • Options with remarkable impacts proposed to improve the overall efficiency. • Novel approach developed to assess the efficiency of multi-factor improvement options. [ABSTRACT FROM AUTHOR]