Integrated Process of Monoethanolamine-Based CO2 Absorption and CO2 Mineralization with SFGD Slag: Process Simulation and Life-Cycle Assessment of CO2 Emission

Low-carbon transport system is desired for sustainable cities. The study aims to compare carbon footprint of two transportation modes in campus transit, bus and bike-share systems, using life-cycle assessment (LCA). A case study was conducted for the four-campus (College Ave, Cook/Douglass, Busch, Livingston) transit system at Rutgers University (New Brunswick, NJ). The life-cycle of two systems were disaggregated into four stages, namely, raw material acquisition and manufacture, transportation, operation and maintenance, and end-of-life. Three uncertain factors—fossil fuel type, number of bikes provided, and bus ridership—were set as variables for sensitivity analysis. Normalization method was used in two impact categories to analyze and compare environmental impacts. The results show that the majority of CO2 emission and energy consumption comes from the raw material stage (extraction and upstream production) of the bike-share system and the operation stage of the campus bus system. The CO2 emission and energy consumption of the current campus bus system are 46 and 13 times of that of the proposed bike-share system, respectively. Three uncertain factors can influence the results: (1) biodiesel can significantly reduce CO2 emission and energy consumption of the current campus bus system; (2) the increased number of bikes increases CO2 emission of the bike-share system; (3) the increase of bus ridership may result in similar impact between two systems. Finally, an alternative hybrid transit system is proposed that uses campus buses to connect four campuses and creates a bike-share system to satisfy travel demands within each campus. The hybrid system reaches the most environmentally friendly state when 70% passenger-miles provided by campus bus and 30% by bike-share system. Further research is needed to consider the uncertainty of biking behavior and travel choice in LCA. Applicable recommendations include increasing ridership of campus buses and building a bike-share in campus to support the current campus bus system. Other strategies such as increasing parking fees and improving biking environment can also be implemented to reduce automobile usage and encourage biking behavior.

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Is Agriculture Always a GHG Emitter? A Combination of Eddy Covariance and Life Cycle Assessment Approaches to Calculate C Intake and Uptake in a Kiwifruit Orchard

Sustainability ◽

10.3390/su13126906 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6906

Author(s):

Federica Rossi ◽

Camilla Chieco ◽

Nicola Di Virgilio ◽

Teodoro Georgiadis ◽

Marianna Nardino

Keyword(s):

Life Cycle Assessment ◽

Life Cycle ◽

Greenhouse Gases ◽

Eddy Covariance ◽

Large Scale ◽

Cropping Systems ◽

Substantial Reduction ◽

Co2 Absorption ◽

Positive Contribution ◽

Efficiency Ratio

While a substantial reduction of GHG (greenhouse gases) is urged, large-scale mitigation implies a detailed and holistic knowledge on the role of specific cropping systems, including the effect of management choices and local factors on the final balance between emissions and removals, this last typical of cropping systems. Here, a conventionally managed irrigated kiwifruit orchard has been studied to assess its greenhouse gases emissions and removals to determine its potential action as a C sink or, alternately, as a C source. The paper integrates two independent approaches. Biological CO2 fluxes have been monitored during 2012 using the micrometeorological Eddy covariance technique, while life cycle assessment quantified emissions derived from the energy and material used. In a climatic-standard year, total GHG emitted as consequence of the management were 4.25 t CO2-eq−1 ha−1 yr−1 while the net uptake measured during the active vegetation phase was as high as 4.9 t CO2 ha−1 yr−1. This led to a positive contribution of the crop to CO2 absorption, with a 1.15 efficiency ratio (sink-source factor defined as t CO2 stored/t CO2 emitted). The mitigating activity, however, completely reversed under extremely unfavorable climatic conditions, such as those recorded in 2003, when the efficiency ratio became 0.91, demonstrating that the occurrence of hotter and drier conditions are able to compromise the capability of Actinidia to offset the GHG emissions, also under appropriate irrigation.

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Life-Cycle Assessment and Monetary Measurements for the Carbon Footprint Reduction of Public Buildings

Sustainability ◽

10.3390/su12083460 ◽

2020 ◽

Vol 12 (8) ◽

pp. 3460 ◽

Cited By ~ 6

Author(s):

Maria Rosa Trovato ◽

Francesco Nocera ◽

Salvatore Giuffrida

Keyword(s):

Life Cycle Assessment ◽

Life Cycle ◽

Carbon Footprint ◽

Co2 Emission ◽

Temperate Climate ◽

Residual Value ◽

Public Buildings ◽

Energy Retrofit ◽

Low Co2 ◽

Study Results

Energy consumption in public buildings increased drastically over the last decade. Significant policy actions towards the promotion of energy efficiency in the building sector have been developed involving sustainable low-CO2-emission technologies. This paper presents the results of an economic–environmental valuation of a standard energy retrofit project for a public building in a Mediterranean area, integrating a life-cycle assessment (LCA) into the traditional economic–financial evaluation pattern. The study results show that simple retrofit of sustainable low-CO2-emission strategies such as wooden double-glazed windows, organic external wall insulation systems, and green roofs can reduce energy needs for heating and cooling by 58.5% and 33.4%, respectively. Furthermore, the implementation of an LCA highlights that the use of sustainable materials reduces the building’s carbon footprint index by 54.1% after retrofit compared to standard materials, thus providing an additional increase in the socio-environmental–economic–financial results of 18%. Some proposals are made about the accounting of the replacement costs and the residual value as requested in the logic of life-cycle cost (that is the economic extension of the LCA), namely concerning the method to take into account the replacement costs and the residual value. The economic calculation highlights the fundamental role played by tax benefits supporting the building energy retrofit, also in temperate climate zones, thus allowing the creation of environmental benefits in addition to remarkable cost savings.

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Integrating LCA with Process Modeling for the Energetic and Environmental Assessment of a CHP Biomass Gasification Plant: A Case Study in Thessaly, Greece

Eng ◽

10.3390/eng1010002 ◽

2020 ◽

Vol 1 (1) ◽

pp. 2-30

Author(s):

Ioannis Voultsos ◽

Dimitrios Katsourinis ◽

Dimitrios Giannopoulos ◽

Maria Founti

Keyword(s):

Life Cycle Assessment ◽

Life Cycle ◽

Moisture Content ◽

Process Simulation ◽

Energy Savings ◽

Biomass Gasification ◽

Lower Efficiency ◽

Technical Parameters ◽

Gasification Process ◽

Gasification Plant

The energetic and environmental performance of a cogeneration biomass gasification plant, situated in Thessaly, Greece is evaluated via a methodology combining process simulation and Life Cycle Assessment (LCA). Initially, the gasification process of the most common agricultural residues found in the Thessaly region is simulated to establish the effect of technical parameters such as gasification temperature, equivalence ratio and raw biomass moisture content. It is shown that a maximum gasification efficiency of approximately 70% can be reached for all feedstock types. Lower efficiency values are associated with increased raw biomass moisture content. Next, the gasifier model is up-scaled, achieving the operation of a 1 MWel and 2.25 MWth cogeneration plant. The Life Cycle Assessment of the operation of the cogeneration unit is conducted using as input the performance data from the process simulation. Global Warming Potential and the Cumulative Demand of Non-Renewable Fossil Energy results suggest that the component which had the major share in both impact categories is the self-consumption of electricity of the plant. Finally, the key conclusion of the present study is the quantification of carbon dioxide mitigation and non-renewable energy savings by comparing the biomass cogeneration unit operation with conventional reference cases.

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99/01520 Reduction in CO2 emission by biomass power generation with sustainable afforestation. Evaluation by LCA (Life Cycle Assessment)

Fuel and Energy Abstracts ◽

10.1016/s0140-6701(99)96701-2 ◽

1999 ◽

Vol 40 (2) ◽

pp. 153

Keyword(s):

Power Generation ◽

Life Cycle Assessment ◽

Life Cycle ◽

Co2 Emission

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Process simulation and gate-to-gate life cycle assessment of hydrometallurgical refractory gold concentrate processing

The International Journal of Life Cycle Assessment ◽

10.1007/s11367-019-01723-6 ◽

2019 ◽

Vol 25 (3) ◽

pp. 456-477 ◽

Cited By ~ 1

Author(s):

Heini Elomaa ◽

Pia Sinisalo ◽

Lotta Rintala ◽

Jari Aromaa ◽

Mari Lundström

Keyword(s):

Global Warming ◽

Life Cycle Assessment ◽

Life Cycle ◽

Environmental Impacts ◽

Process Simulation ◽

Development Stage ◽

Environmental Indicators ◽

Gold Recovery ◽

Pressure Oxidation ◽

Refractory Gold

Abstract Purpose Currently, almost all cyanide-free gold leaching processes are still in the development stage. Proactively investigating their environmental impacts prior to commercialization is of utmost importance. In this study, a detailed refractory gold concentrate process simulation with mass and energy balance was built for state-of-the-art technology with (i) pressure oxidation followed by cyanidation and, compared to alternative cyanide-free technology, with (ii) pressure oxidation followed by halogen leaching. Subsequently, the simulated mass balance was used as life cycle inventory data in order to evaluate the environmental impacts of the predominant cyanidation process and a cyanide-free alternative. Methods The environmental indicators for each scenario are based on the mass balance produced with HSC Sim steady-state simulation. The simulated mass balances were evaluated to identify the challenges in used technologies. The HSC Sim software is compatible with the GaBi LCA software, where LCI data from HSC-Sim is directly exported to. The simulation produces a consistent life cycle inventory (LCI). In GaBi LCA software, the environmental indicators of global warming potential (GWP), acidification potential (AP), terrestrial eutrophication potential (EP), and water depletion (Water) are estimated. Results and discussion The life cycle assessment revealed that the GWP for cyanidation was 10.1 t CO2-e/kg Au, whereas the halogen process indicated a slightly higher GWP of 12.6 t CO2-e/kg Au. The difference is partially explained by the fact that the footprint is calculated against produced units of Au; total recovery by the halogen leaching route for gold was only 87.3%, whereas the cyanidation route could extract as much as 98.5% of gold. The addition of a second gold recovery unit to extract gold also from the washing water in the halogen process increased gold recovery up to 98.5%, decreasing the GWP of the halogen process to 11.5 t CO2-e/kg Au. However, both evaluated halogen processing scenarios indicated a slightly higher global warming potential when compared to the dominating cyanidation technology. Conclusions The estimated environmental impacts predict that the development-stage cyanide-free process still has some challenges compared to cyanidation; as in the investigated scenarios, the environmental impacts were generally higher for halogen leaching. Further process improvements, for example in the form of decreased moisture in the feed for halide leaching, and the adaptation of in situ gold recovery practices in chloride leaching may give the cyanide-free processing options a competitive edge.

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