Abstract

Wellbore optimization is one of the key factors in field management and development of multi layer deltaic reservoirs having a wide range of reservoir properties and size. This optimization will affect current field deliverability and the number of wells required to be drilled in the future to meet gas demand. Tubing size is one of the factors that can be used for wellbore, optimization. This paper presents VICO Indonesia's experience in optimizing tubing restricted wells in Nilam Field.

The results of a VICO Tubing Size Optimization Study showed that larger tubing size does not significantly affect reserve recovery in high kh (permeability thickness) reservoirs. All wells were evaluated to determine which wells were tubing restricted and candidates for optimization. The optimization work included tubing change-out with a rig and rigless wireline intervention. Nodal Analysis and DEPLAN, a Field Depletion Planning model developed by VICO Indonesia, were used as tools to identify the candidate wells and estimate the benefits of the production optimization.

The 1995 optimization program resulted in an 87 MMSCFD gas deliverability increase. This increase will result in the two year deferral of three deliverability drilling wells and two less deliverability drilling wells during the field life. This paper discusses not only the obvious benefits of increasing the production, but also the effects on reservoir depletion planning and ultimate recovery.