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1.
Environ Technol ; 34(1-4): 1-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23530309

RESUMO

In this research the catalytic effect of copper compounds (ionic, oxide and oxide nanopowder) on the oxidation of ferrous iron by aeration was studied experimentally. When copper exists in solution, the oxidation rate of iron(II) will increase. The experimental results showed that the oxidation rate increases with an increasing copper concentration. From the experimental data it can be determined that the copper oxide nanopowder is the most effective for the oxidation reaction among the used copper forms. Aeration is the most economical oxidation method when water exhibits a high ferrous iron concentration.


Assuntos
Cobre/química , Ferro/química , Movimentos do Ar , Catálise , Concentração de Íons de Hidrogênio , Nanopartículas , Oxirredução , Abastecimento de Água
2.
J Environ Radioact ; 109: 71-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22321893

RESUMO

An investigation was carried out to find out the concentration of Naturally Occurring Radioactive Materials (NORMs) in an oil production unit, an evaporation pond, and a drilling site in the Khuzestan province, in south west Iran the 4th largest oil producing country in the world. The nuclides (232)Th and (40)K were determined in soil samples and (226)Ra was analyzed in both soil and water. The (232)Th ranged between 8.7 and 403 Bq kg(-1), while the minimum concentration for (40)K was much larger, i.e. 82 Bq kg(-1) and its maximum concentration was 815 Bq kg(-1). Soil samples indicated very low concentrations of (226)Ra, typically between 10.6 and 42.1 Bq kg(-1) with some exceptions of 282, 602, and even 1480 Bq kg(-1). Also, the range for (226)Ra in water was less from 0.1 to a maximum 30.3 Bq L(-1). Results show that on average, NORM concentrations in these areas are lower in comparison with the usual concentration levels in typical oil and gas fields, but despite this fact, necessary measures have to be taken in order to minimize the environmental impact of radioactive materials.


Assuntos
Radiação de Fundo , Petróleo , Irã (Geográfico)
3.
Environ Monit Assess ; 184(5): 2981-91, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21739281

RESUMO

Strategic health, safety, and environmental management system (HSE-MS) involves systematic and cooperative planning in each phase of the lifecycle of a project to ensure that interaction among the industry group, client, contractor, stakeholder, and host community exists with the highest level of health, safety, and environmental standard performances. Therefore, it seems necessary to assess the HSE-MS performance of contractor(s) by a comparative strategic management model with the aim of continuous improvement. The present Strategic Management Model (SMM) has been illustrated by a case study and the results show that the model is a suitable management tool for decision making in a contract environment, especially in oil and gas fields and based on accepted international standards within the framework of management deming cycle. To develop this model, a data bank has been created, which includes the statistical data calculated by converting the HSE performance qualitative data into quantitative values. Based on this fact, the structure of the model has been formed by defining HSE performance indicators according to the HSE-MS model. Therefore, 178 indicators have been selected which have been grouped into four attributes. Model output provides quantitative measures of HSE-MS performance as a percentage of an ideal level with maximum possible score for each attribute. Defining the strengths and weaknesses of the contractor(s) is another capability of this model. On the other hand, this model provides a ranking that could be used as the basis for decision making at the contractors' pre-qualification phase or during the execution of the project.


Assuntos
Monitoramento Ambiental , Modelos Teóricos , Gestão da Segurança/métodos , Técnicas de Apoio para a Decisão , Meio Ambiente , Poluição Ambiental/estatística & dados numéricos , Inquéritos Epidemiológicos , Humanos , Campos de Petróleo e Gás
4.
J Colloid Interface Sci ; 324(1-2): 172-6, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18513733

RESUMO

The production and properties of a biosurfactant, synthesized by a member of the Bacillus subtilis group (PTCC 1696) which was isolated from an Iranian oil field, have been investigated. The biosurfactant, which was produced as a primary metabolite associated with the growth of PTCC 1696, was able to reduce the surface and interfacial tension of media to 26.7 and 0.1 mN/m, respectively. Crude biosurfactant and acid precipitated biosurfactant have critical micelle concentrations of 10 and 100 mug/ml, respectively. The stability of the biosurfactant at different salinities, pH and temperature and also its emulsifying activity have been investigated. It is an effective surfactant at very low concentrations over a wide range of temperatures, pHs and salt concentrations and also has the ability to emulsify oil, which is essential for enhanced oil recovery.


Assuntos
Bacillus subtilis/química , Microbiologia Industrial , Petróleo , Tensoativos/isolamento & purificação , Concentração de Íons de Hidrogênio , Sais , Tensão Superficial , Temperatura
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