Prediction of Production Performance of Horizontal Wells in Heterogeneous Reservoir
Mohd Shah, Nur Shazren
Engineering Honours Degree, 2006
University of Adelaide
The basic ground of drilling horizontal wells is to increase well performance in reservoirs which may not be achieved from conventional wells. Accurate prediction of such performance is one of the most important critical considerations involved in planning a successful drilling operation. Both analytical and numerical tools have been developed for this purpose, involving a lot of important parameters. Unfortunately, the predictions made by these tools rarely match the actual performance, except in cases where sufficient production data are available. A poor prediction of horizontal well performance may lead to a severe loss of actual desired production. Underestimating or overestimating the production will affect decisions in the next phases. The actual production performance of horizontal well depends on various reservoir parameters such as permeability anisotropy and reservoir thickness; and well parameters such as well configurations and well lengths. Therefore, optimum production performance can be achieved when a proper combination of these parameters meet certain objective criteria.
An attempt has been made to explore the effects of few important parameters on horizontal wells production performance. Comprehensive literature survey has been conducted in order to acquire the fundamental understanding as well as to find the available productivity equations of predicting well performance. An analysis on well performance is performed against several parameters including permeability anisotropy, well configurations, reservoir thickness and well length. The influences of these four parameters on production performance in horizontal wells are investigated based on a sample case study using analytical equations. From this study, it can clearly be seen how these four parameters can significantly influence production performance in horizontal wells, either increase the desired performance or lessen the productivity in potentially producing reservoirs. This is very crucial because it provides basic knowledge on how the reservoirs would behave during production of horizontal wells.
All results are concluded and some recommendations are made to clear any negativity in performing this analysis and to pave the way for a better future of horizontal wells applications in oil and gas industry.