Ingeniera De Petroleos

SPE 152885152885-PP
Probabilistic Risk Analysis Applied to the Evaluation of Alternatives for Management and/ or Exclusion of Sand
Manuel G. Jaimes, SPE, Ecopetrol S.A., Fabio E. Sanabria, Ecopetrol S.A., Yair A. Quintero, SPE, Ecopetrol S.A., Gilma Y. Contreras, Natfrac Corporation, Diana P. Martin, SPE, Natfrac Corporation.
Copyright 2012, Society of Petroleum Engineers

This paper wasprepared for presentation at the SPE Latin American and Caribbean Petroleum Engineering Conference held in Mexico City, Mexico, 16–18 April 2012.

This paper was selected for presentation by an SPE program committee following review of information contained in an abstract submitted by the author(s). Contents of the paper have not been reviewed by the Society of Petroleum Engineers and are subjectto correction by the author(s). The material does not necessarily reflect any position of the Society of Petroleum Engineers, its officers, or members. Electronic reproduction, distribution, or storage of any part of this paper without the written consent of the Society of Petroleum Engineers is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words;illustrations may not be copied. The abstract must contain conspicuous acknowledgment of SPE copyright.
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Abstract
Sand production is a critical problem that causes the industry spending over $3.0 Billion U.S. per year (70% of the wells worldwide have this problem). To mitigate the impact, many operators choose the option of deployingtechnologies to exclude the sand, and usually reduce the benefits for decrease a risk not quantified.

Currently the reservoirs trending to sand production contain an increasing percentage of the world's hydrocarbon reserves. Many of the wells that exploit these resources are producing beyond the limits of their originally estimated useful life, which can result in weak formations. Consequently, it isrequired being more demanding in the profit margins of the projects of Management and / or sand control achieved at these reservoirs, so it requires a probabilistic risk analysis (PRA) in them, taking into account that the risk and uncertainty are two factors that are often present. This analysis facilitates decision making and allows determine the best Completion and production strategy of theformations sensitive at sand production.

Based on the above, this work focuses on developing a methodology for probabilistic risk analysis to evaluate management alternatives and / or exclusion of sand using Monte Carlo simulation. The methodology includes six phases: (1) Selection of alternatives to evaluate and definition of the conditions of production of each one, (2) Structuring thedeterministic model of each alternative (3) identification of most impacting variables on the level of production of each alternative and determination of its range of typical behavior (4) Estimation of probability distributions of production for each variable, (5) Monte Carlo simulation for risk assessment of each alternative and selecting the best choice.

The methodology was applied to evaluatemanagement alternatives and / or exclusion of sand in the formations sensitive to sand production of the fields: Lisama, Llanito, Galan, Brisas and YariguiCantagallo in Colombia and was compared with the results of the evaluation when using deterministic models. In this paper is present the Application cases in the wells: Lisama 171 and Yarigui 168.

Finally, the main findings, conclusions andrecommendations obtained in this study are shown.

Introduction
A large number of wells located in the basin of the Middle Magdalena Valley in Colombia are a loss in productivity due to high sand production associated with oil production, so it is necessary to evaluate and implement alternatives to exclusion and / or management of sand.

Until recently operators took the option to exclude the...