Dissertação

{pt_PT=Plugging effects caused by polymer injections in glass-silicon-glass micromodels} {} EVALUATED

{pt=Polymer flooding improves the mobility ratio and leads to an increase in total oil recovery (Romero-Zeron, 2012). However, due to their structure, polymers tend to be retained by the rock, which decreases permeability and total production (Sorbie, 1991). Glass-silicon-glass micromodel flooding are a relatively novel experiment type used to assess the effectiveness of different EOR methods, which allow for the visualisation of fluid flow at pore level (Wegner et al., 2015). This paper thus applies micromodel visualisation to the study of polymer retention, also known as plugging effects. Plugging effects have been noted as being concentrated near the injector well (Sorbie, 1991) in oil fields; hence streamline visualisation was used to confirm this distribution pattern at microscopic level. The experiment involved successive injections of brine and polymer solution, together with a fluorescent tracer particle, to ease the visualisation of fluid flow. The differential pressure within the micromodel was also measured. Analysis of plugging distribution showed that polymer retention was greatest near the injection point, and generally concentrated along the main axis of flow; more peripheral areas were less affected. Study of the evolution of plugging over time showed that it was permanent, with the injection of certain organic molecules even worsening the symptoms; the tracer particle in particular, while having no effect of its own, was found to interact with retained polymers and increase plugging. Pore size was found to be correlated with the degree of polymer retention; the analysis of plugged pores showed that none were above 405 µm., en=Polymer flooding improves the mobility ratio and leads to an increase in total oil recovery (Romero-Zeron, 2012). However, due to their structure, polymers tend to be retained by the rock, which decreases permeability and total production (Sorbie, 1991). Glass-silicon-glass micromodel flooding are a relatively novel experiment type used to assess the effectiveness of different EOR methods, which allow for the visualisation of fluid flow at pore level (Wegner et al., 2015). This paper thus applies micromodel visualisation to the study of polymer retention, also known as plugging effects. Plugging effects have been noted as being concentrated near the injector well (Sorbie, 1991) in oil fields; hence streamline visualisation was used to confirm this distribution pattern at microscopic level. The experiment involved successive injections of brine and polymer solution, together with a fluorescent tracer particle, to ease the visualisation of fluid flow. The differential pressure within the micromodel was also measured. Analysis of plugging distribution showed that polymer retention was greatest near the injection point, and generally concentrated along the main axis of flow; more peripheral areas were less affected. Study of the evolution of plugging over time showed that it was permanent, with the injection of certain organic molecules even worsening the symptoms; the tracer particle in particular, while having no effect of its own, was found to interact with retained polymers and increase plugging. Pore size was found to be correlated with the degree of polymer retention; the analysis of plugged pores showed that none were above 405 µm.}
{pt=Polymer, EOR, plugging, micromodel, en=Polymer, EOR, plugging, micromodel}

Abril 12, 2018, 17:30

Publicação

Obra sujeita a Direitos de Autor

Orientação

ORIENTADOR

Maria João Correia Colunas Pereira

Departamento de Engenharia Civil, Arquitectura e Georrecursos (DECivil)

Professor Associado