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Buildings play a central role in the low-carbon future and pose challenges for integration with sustainable development, especially in Brazil, where urban areas are still expanding and the implementation of environmental tools, such as Life Cycle Assessment (LCA), faces more difficulties. The aim of this paper is to assess the greenhouse gases (GHG) emissions during the whole life cycle of a housing complex located in Rio de Janeiro, Brazil. For this purpose, a life cycle-based analysis was carried out to estimate the GHG emission from the production of the most commonly used building materials, such as steel, cement, ceramic, wood, among others; transport activities; and the construction, use (energy consumption during 50-year useful life), maintenance and demolition of the housing complex. According to the results, the GHG emissions generated during the housing complex's life cycle are 282.62 tCO2eq, which can be expressed as 1,009.34 kg CO2eq./m2/50-year or 20.19 kg CO2eq./m2/year. These emissions are dominated by the use stage (56%), which is followed by the pre-use (30%) and end-of-life (14%) stages. Indirect emissions accounted for more than half of GHG emissions (57%), mainly driven by emissions from building materials (85.47 t CO2eq.; or 30%). Cement was responsible for 22% of embodied GHG emissions from building materials. These findings are relevant to the Brazilian context in which environmental issues have not determined the choice of building materials. Furthermore, this paper supports the improvement of the LCA usefulness in Brazil as it contributes to the mitigation of the lack of national datasets. [ABSTRACT FROM AUTHOR]

Abstract: This study aims at estimating the abatement costs of CO2 emissions of the Brazilian oil refining sector. For greenfield refineries that will be built until 2030, mitigation options include the modification of refining schemes and efficiency gains in processing units. For existing refineries and those already under construction, only mitigation options based on efficiency gains in processing units are evaluated. The abatement cost of each mitigation option was determined on the basis of incremental costs compared with a reference scenario. Two discount rates were applied: one adopted by the Brazil’s government official long term plan (8% p.a.), and another typically adopted by the private oil sector (15% p.a.). Findings indicate that refineries face high abatement costs. The cost of changing the processing scheme of greenfield plants reaches US$100/tCO2 at 15% p.a. discount rate. Even at 8% p.a. discount rate the abatement cost is higher than US$50/tCO2. The most promising alternative is thermal energy management, whose abatement cost equals US$20/tCO2 at 8% p.a. discount rate. However, private investors perceive this option at US$80/tCO2, which is still high. This difference in cost indicates the need for public policies for promoting carbon mitigation measures in Brazilian oil refineries. [Copyright &y& Elsevier]

Abstract: This study evaluates the possibility of installing an offshore gas-to-liquids (GTL) plant in Brazil to reduce Natural Gas (NG) flaring, curb carbon dioxide equivalent (CO2e) emissions and produce premium diesel. CO2e emissions abatement costs were estimated by comparing two alternatives. The first alternative (baseline) considers that the volume of NG flared will not be reduced. Low-sulfur fuels (diesel and naphtha) will be obtained by investing in treatment units in Brazilian refineries. These are hydrotreating units for unstable compounds and hydrodesulfurizer units for fluid catalytic cracking (FCC) naphtha. Currently in Brazilian refineries, without any investment, the lower-quality streams that should be removed from diesel and gasoline pools to comply with higher specifications are light-cycle oil and FCC naphtha, respectively. The second alternative considers an offshore microchannel GTL plant producing synthetic crude oil, or syncrude. The upgrading of this syncrude is done by a mild-hydrocracking unit. This alternative allows the production of low-sulfur diesel, reducing gas flaring and co-producing high-quality naphtha. The results show that CO2e emissions abatement costs of offshore GTL in Brazil should range between negative US$ 2.00 and positive 80.00/tCO2e. Nevertheless, the typical scenario shows an average figure of US$ 37.00/tCO2e abated. [Copyright &y& Elsevier]