Navegando por Assunto "Mineroduto"

Agora exibindo 1 - 3 de 3

Acesso aberto (Open Access)
Influência da precipitação na atividade de beneficiamento de caulim em Barcarena-Pa e seus impactos socioambientais.
(Universidade Federal do Pará, 2018) LEMOS, Marcos Antonio de Queiroz; PIMENTEL, Márcia Aparecida da Silva; http://lattes.cnpq.br/3994635795557609; ROCHA, Edson José Paulino da; http://lattes.cnpq.br/2313369423727020
Mining in the Stateof Pará occupies a prominent position in the regional and national economies. Although it is installed and operating in compliance with the due process of environmental licensing, mining activity of great degradation potential has been causing environmental disasters and social problems. This work analyzes the polluting events occurring in the period from 2004 to 2016, due to the leakage of tailings and kaolin ore bodies in the Dendê river, Curuperé and Maricá streams, to the Marajó Bay, and the influence of precipitation on the activity of kaolin processing and its social and environmental impacts. The research was based on reports of Police investigations in the Specialized Division of the Environmentof the Civil Police of Pará, expert reports of the Institute of Criminology of the Center for Scientific Expertise Renato Chaves, reports of the Evandro Chagas Institute of the Ministry of Health and the Laboratory of Analytical and Environmental Chemistry of the UFPA, in which authors and materiality were identified, the communities and water bodies affected and the social and environmental impacts resulting from the polluting events. From a descriptive and analytical approach of these events, the socio-environmental impacts were identified, the accelerated growth of the urban population from the installation of the industrial enterprises; the constant damages in the riverside communities located around the mining company; the expansion of areas of environmental risk with the expansion of mining activity in the region and the successive pollution of water resources.
Acesso aberto (Open Access)
Influência das características do fluido na corrosão e erosão em amostras de aço 5l x65
(Universidade Federal do Pará, 2024-09-30) NASCIMENTO, Nina Benchimol Xavier do; FARIA, Lênio José Guerreiro de; http://lattes.cnpq.br/7428609361678173
The objective of this research was to evaluate the corrosive and erosive behavior of API 5L X65 carbon steel samples with an external FBE coating used for transporting an aqueous suspension containing around 40% solids with a high content of aluminum hydrated silicates, mainly kaolinite and water, to identify the best operational method for intermittent pumping regimes, focusing on their influence on steel integrity. The samples were divided as follows: three samples of carbon steel pipes with an outer diameter (OD) of 14 inches, thickness (Th) of 8.74 mm (original), and 1 meter in length; a sample of process water and a sample of aqueous suspension with an average of 40% solids with a high content of aluminum hydrated silicates and acidic pH, each with approximately 60 liters (divided into two plastic containers of 30 liters). The results show that the KM-0 sample presented a yield limit below the specified minimum, and the KM-23 sample also showed a high standard deviation, suggesting a lack of homogeneity. The new pipe samples presented values within specifications. The significant difference in hardness between samples lies in the very low carbon percentage presented in the TR sample. This minimizes issues with potential weak points and increases material weldability; however, in some cases, pipes treated by controlled rolling achieve high mechanical strength and toughness with relatively low hardness, which can provide greater erosion resistance than tempered pipes. Samples KM-23 and KM-0, although having similar hardness and chemical composition, showed differences in absorbed energy and area reduction. This may be attributed to the higher sulfur content in sample KM-23, evidenced by detected sulfur-rich inclusions. Overall toughness was high for all samples, with no indication of brittleness under the tested conditions. The results of uniform and localized corrosion, disregarding the influence of oxygen, indicated that the acidic pH slurry is less corrosive than water. During water operation, the corrosion rate stabilizes over time; however, when production is intermittent, the film formed by water disappears, returning this rate to its initial condition, being even more detrimental to the pipe's integrity.
Acesso aberto (Open Access)
Investigação do processo de corrosão causado pela polpa de bauxita em mineroduto de aço carbono
(2015-03) SANTOS, Marcelo Costa; PINHEIRO, Clairon Lima; CARDOSO FILHO, José Carlos de Araújo
The corrosion caused by the ore slurry transported plays a fundamental role in the lifetime of a pipeline. Thus, the corrosion of API 5L-X70 carbon steel was investigated using process water and bauxite pulp (5% w./v.) as solution and electrochemical techniques. The results of open circuit potential (OCP), polarization and electrochemical impedance spectroscopy (EIS) showed that presence of bauxite caused changes when it compared to water process results and the corrosion rate increased in the bauxite presence. The micrographs of specimens surface obtained by scanning electron microscopy (SEM) showed cracks formation in the oxide in the metal surface and this phenomenon may be responsible for increased corrosion in bauxite presence. The methodology described in this work show to be useful for the investigation of corrosion in pipelines.