Full text
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| Author(s): |
Odair Jose Costa
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Mecânica |
| Defense date: | 2008-12-18 |
| Examining board members: |
Denis José Schiozer;
Paulo Roberto Ribeiro;
Adalberto Jose Rosa
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| Advisor: | Denis José Schiozer |
| Abstract | |
Produced water re-injection is a valuable method of water disposal and pressure and energy support. A common water re-injection problem is the injectivity loss, which affects negatively the process and restrains optimal water injection rates. The injectivity loss can be minimized by water injection with fracture propagation pressure (IFPP), which aims to restore injection capacity. To study this process, a geo-mechanical simulator for fracture modeling combined with a commercial reservoir simulation package is used to model and to optimize the operation condition of water injection wells. The fracture is represented by a virtual horizontal well and analytical formulations of hyperbolic decline of permeability are used to represent the effect of formation damage. This work aims the study of some cases to verify in which situations the IFPP is convenient. The simulation model studied is a synthetic reservoir with a five-spot pattern, representing a region of a reservoir. Three scenarios are considered, with different oil types (light, intermediate and heavy). These scenarios are proposed to reproduce some possible situations, where fracture pressure can be reached by the effect of the injectivity loss or due to rock and fluid characteristics. The behavior of the IFPP is evaluated using the net present value (NPV) and cumulative oil and water productions. The results showed that the IFPP study can be considered as part of an optimization problem of injection flow, where the fracture may occur. It is shown that IFPP, in general, presents advantages for intermediate and high viscosity oil because it anticipates oil production. Studies with light oil indicate that the technique is only interesting when there is significant injectivity loss, where IFPP is desirable for injectivity restoration (AU) | |