Aplicação de RMN no domínio do tempo para desenvolvimento de um método analítico para detecção de incrustações inorgânicas em água de produção
Data
2023-02-28
Autores
Diaz, Gabriel Cespede de Castro 
Orientadores
Barbosa, Lúcio Leonel
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
A extração de água associada ao petróleo é um fator recorrente nos campos de produção de petróleo. Entretanto, o conteúdo dessa água produzida concomitante com o petróleo acarreta algumas inconveniências operacionais e econômicas. Entre os problemas operacionais associados a essa atividade está a deposição de sais inorgânicos (scalling) de sulfato de bário nas paredes das tubulações de produção, o que compromete a garantia de escoamento (flow assurance) e diminui a taxa de produção. A prevenção, controle e remediação de scalling é feita por meio de métodos químicos e físicos, que são dispendiosos e algumas vezes inviáveis do ponto de vista técnico. Assim, o conhecimento da composição química da água de produção e a aplicação de técnicas rápidas, simples, precisas e não destrutivas, constituem uma excelente alternativa para detectar incrustações, e assim fornecer informações indispensáveis para evitar ou controlar a formação de compostos químicos incrustantes. Este trabalho propõe o emprego da técnica de Ressonância Magnética no Domínio do Tempo (RMN-DT) para detectar e quantificar incrustações inorgânicas. O tempo de relaxação transversal (T2) foi correlacionado com a massa de precipitados formada em misturas com diferentes proporções volumétricas de água do mar e água sintética. Os resultados mostraram que os valores de T2 das misturas reduz de forma proporcional aumento da quantidade de precipitados na faixa entre 1,65s para águas de formação com presença de precipitado e 1,29s para água do mar sem precipitado, isso pode ser observado através da média dos coeficientes de determinação que foi de aproximadamente 0,90. Pode-se concluir a partir dos resultados que a técnica de RMN-DT apresenta potencial para detectar e quantificar incrustações inorgânicas, porém são necessários outros testes com outras técnicas como cromatografia de íons e Espectrometria de Emissão Óptica por Plasma Acoplado Indutivamente (ICP-OES) para que seja possível consolidar a metodologia proposta neste trabalho.
Water production as a byproduct during oil and gas extraction is recurrent in oilfield, and this “produced water” creates operational and economic issues to this activity. Among the operational issues caused by the produced water is the scaling of inorganic salts in pipe walls, that can lower the flow assurance and the efficiency of the oil production system, rising the pressure in the pipe, that could cause accidents during the production. There are some ways to remedy or prevent this kind of operational issue, physically or chemically, although, some of these technics are inviable, mainly because of its cost. Therefore, it is necessary a detailed chemical analysis of the water conditions, and it has to be a rapid, simple, precise and non-destructive technic and it can be associated with the already known technics to detect inorganic scaling to help preventing this kind of problem and lowering the chance of operational issues and also the cost of the production. This dissertation proposes the use of the Time Domain Nuclear Magnetic Resonance (TD-NMR) technique to detect and quantify inorganic scaling. The transverse relaxation time (T2) was correlated with the mass of scaling formed in mixtures with different volumetric proportions of synthetic seawater and synthetic formation water. The results showed that the T2 of the mixtures decreases proportionally to the increase of scaling in the ranges between 1.65s for formation waters with a high rate of scale and 1.29s for sea water without scale, this can be observed through the average of the coefficients of determination which was approximately 0.90. It can be concluded from the results that the TD-NMR technique has the potential to detect and quantify inorganic encrustations, but more in-depth TD-NMR tests are needed, as well as other technologies as ion chromatography and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) so that it is possible to consolidate the methodology for the detection of inorganic encrustations in water produced from petroleum.
Water production as a byproduct during oil and gas extraction is recurrent in oilfield, and this “produced water” creates operational and economic issues to this activity. Among the operational issues caused by the produced water is the scaling of inorganic salts in pipe walls, that can lower the flow assurance and the efficiency of the oil production system, rising the pressure in the pipe, that could cause accidents during the production. There are some ways to remedy or prevent this kind of operational issue, physically or chemically, although, some of these technics are inviable, mainly because of its cost. Therefore, it is necessary a detailed chemical analysis of the water conditions, and it has to be a rapid, simple, precise and non-destructive technic and it can be associated with the already known technics to detect inorganic scaling to help preventing this kind of problem and lowering the chance of operational issues and also the cost of the production. This dissertation proposes the use of the Time Domain Nuclear Magnetic Resonance (TD-NMR) technique to detect and quantify inorganic scaling. The transverse relaxation time (T2) was correlated with the mass of scaling formed in mixtures with different volumetric proportions of synthetic seawater and synthetic formation water. The results showed that the T2 of the mixtures decreases proportionally to the increase of scaling in the ranges between 1.65s for formation waters with a high rate of scale and 1.29s for sea water without scale, this can be observed through the average of the coefficients of determination which was approximately 0.90. It can be concluded from the results that the TD-NMR technique has the potential to detect and quantify inorganic encrustations, but more in-depth TD-NMR tests are needed, as well as other technologies as ion chromatography and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) so that it is possible to consolidate the methodology for the detection of inorganic encrustations in water produced from petroleum.
Descrição
Citação
DIAZ, Gabriel Cespede de Castro Diaz. Aplicação de rmn no domínio do tempo para desenvolvimento de um método analítico para detecção de incrustações inorgânicas em água de produção. 2023. 83 f. Dissertação (Mestrado Interdisciplinar em Ciência e Tecnologia do Mar) - Instituto do Mar, Universidade Federal de São Paulo, Santos, 2023.