HEURISTIC ALGORITHMS FOR THE PROBLEM OF OPTIMIZATION OF THE DRAIN AREA IN UNCONVENTIONAL FIELDS OF HYDROCARBONS

Keywords: Unconventional fields, greedy algorithm, ant colony, entire linear programming.

In this paper we study the problem of optimizing the operations of unconventional oil and gas fields, with the objective of maximizing total output. The problem consists of covering the field map with rectangular pads having prespecified configurations, in such a way that each pad is completely included within the field, pads do not overlap, and surface structures (called locations) do not hit geographical accidents or existing buildings.
In a previous work, a linear programming based procedure was presented for this problem, and this procedure allowed to solve real-life instances, albeit -in some cases- producing plans with overlappings among the pads (since a relaxation is solved) and suffering from memory issues.
In this work we present heuristics for this problem, that avoid these issues. In particular, we introduce two greedy procedures, two ant colony based algorithms, and two integer programming based procedures. The first greedy algorithm is quite simple, whereas the second one resorts to a local search in order to find better solutions. Both algorithms use a discretization of the field, and running times increase as the discretization is refined. In order to avoid this situation, we introduce procedures based on ant colonies, which do not discretize the field map.

Finally, we propose two enhancements to the existing procedure based on integer programming, with the objective of avoiding pad overlappings. The first of such procedures first solves the linear relaxation on a broad discretiza- tion, and takes advantage of this information in a second model. The second procedure is a direct modification of the existing algorithm, with the objective of avoiding pad overlappings.
We present computational experiments studying the effectiveness of the proposed algorithms.

Links to work:
http://dc.sigedep.exactas.uba.ar/media/academic/grade/thesis/tesis-crusso.pdftart writing here...