Hot-mix asphalt used in pavement layers is produced by asphalt plants. In Brazil, despite the fact that these industrial units produce greenhouse gases, no control or measurement protocol has yet been established. This study aims to quantify emissions in different asphalt plants, in terms of carbon dioxide equivalent (CO2eq) and energy consumption. Asphalt plants were selected according to their type (batch or drum mix); production capacity (80 to 340 t/h), and whether mobile or fixed. In each plant, emissions were quantified and the energy consumption spent on drying and heating aggregates in the dryer drum was evaluated. The fuels used in the drier drum such as low pour point (LPP) oil, liquefied petroleum gas (LPG), and natural gas (NG) were evaluated and compared. The methodology consisted of surveying the thermal power of the dryer drum specified on the suppliers' catalog to calculate the volume of fuel required per ton of asphalt mixture produced. Based on the criterion of the lower calorific value of each fuel, the volume of fuel used was calculated according to the production of the asphalt plants. Through the GHC protocol tool, the quantification of emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) gases was obtained, and then transformed into CO2eq emissions. As a result, lower energy consumption was observed in the mobile batch plants and higher consumption in the mobile counterflow drum mix plants. On average, 27.69% less energy per ton of processed aggregate was needed compared to the mobile counterflow plants. The use of natural gas in the dryer drum and for all plant models was the least emissive fuel. The results showed that for the mobile batch type with a capacity of 140 t/h, the emission was 13.62 kg of CO2eq / t. On the other hand, with the mobile counterflow type with a capacity of 200 t/h, 13.64 kg of CO2eq/t was produced. Finally, with the fixed counterflow type with a production capacity of 240 t/h and 300 t/h, emissions of 13.67 kg of CO2eq/t were obtained. Through this study, the mobile batch plant with a capacity of 140 t/h using natural gas showed the least environmental impact. When natural gas was used, this model obtained energy consumption and emissions 54.5% lower than the mobile counterflow model with a capacity of 50 t/h which showed the worst environmental performance.

Com a crescente demanda por estruturas que suportam elevados volumes de tráfego, excesso de carga, melhor desempenho e menor necessidade de intervenções para reparos ou manutenções, é necessário que novos materiais sejam estudados ou desenvolvidos para sanar tais necessidades. Dentre as misturas asfálticas usinadas a quente, pode-se destacar a Stone Matrix Asphalt (SMA) que foi desenvolvida e melhorada ao longo do tempo para atender rodovias com pesado volume de tráfego. Neste trabalho, foram analisados os efeitos da adição da cal hidratada sobre a resistência à tração da mistura SMA e o efeito da utilização da fibra de vidro tipo E na mitigação do escorrimento do ligante betuminoso. Utilizou-se ligante asfáltico modificado por polímero (CAP 60/85-E), fibra de vidro tipo E, areia artificial, agregado basáltico e cal. Os corpos de prova foram submetidos aos ensaios para definição dos parâmetros Marshall, ensaio de escorrimento (Schellemberg) e resistência à tração por compressão diametral. O teor de ligante foi fixado em 7% devido aos resultados obtidos nos parâmetros Marshall. No ensaio de escorrimento foi observado teor adequado para a mistura com 0,5% fibra de vidro. Já no ensaio de resistência à tração foi constatada perda de resistência do teor de 1,5% de cal quando comparado a 1%, entretanto ambos percentuais apresentaram resistência superior ao prescrito pela ET-DE-P00/031.

Urban streams are increasingly suffering from anthropogenic activities, mainly due to domestic sewage. Thus, this study aimed to assess the impact of treated domestic effluent on a receiving water body. Four sampling points were defined. The first was inside the stream, located upstream on the Wastewater Treatment Plant (WWTP), the second at the WWTP inlet, the third at the plant outlet and the last was located inside the stream, downstream of the WWTP discharge. The study was carried on for a three-year period (2013)(2014)(2015). Chemical, physical and biological parameters were analyzed. Correlation analysis, Principal Component Analysis (PCA) and Euclidean distance dendrogram then assessed the results. At the sampling points related to the stream (spots 1 and 4), a significant distance between conductivity and the other parameters was observed, suggesting a low relation between them. A group of minor related variables (Trophic State Index -TSI -and Chemical Oxygen Demand -COD) was formed. At the sampling points within the WWTP (points 2 and 3), the formation of 3 clusters was observed, and two of them involved TSI, thus indicating that this parameter changes according to the season of the year and the monitoring point. Therefore, the WWTP influences in a significant and proportional way the TSI of the water body in different seasons of the year, suggesting that this is the main parameter to be controlled. The highest TSI were observed during spring and summer.

Urban streams are increasingly suffering from anthropogenic activities, mainly due to domestic sewage. Thus, this study aimed to assess the impact of treated domestic effluent on a receiving water body. Four sampling points were defined. The first was inside the stream, located upstream on the Wastewater Treatment Plant (WWTP), the second at the WWTP inlet, the third at the plant outlet and the last was located inside the stream, downstream of the WWTP discharge. The study was carried on for a three-year period (2013)(2014)(2015). Chemical, physical and biological parameters were analyzed. Correlation analysis, Principal Component Analysis (PCA) and Euclidean distance dendrogram then assessed the results. At the sampling points related to the stream (spots 1 and 4), a significant distance between conductivity and the other parameters was observed, suggesting a low relation between them. A group of minor related variables (Trophic State Index -TSI -and Chemical Oxygen Demand -COD) was formed. At the sampling points within the WWTP (points 2 and 3), the formation of 3 clusters was observed, and two of them involved TSI, thus indicating that this parameter changes according to the season of the year and the monitoring point. Therefore, the WWTP influences in a significant and proportional way the TSI of the water body in different seasons of the year, suggesting that this is the main parameter to be controlled. The highest TSI were observed during spring and summer.