Abstract

This paper shows the results of conceptual studies for the design of thermally bundled wells to optimize the heavy oil production of the offshore fields in the Gulf of Mexico.

During the last recent years, PEMEX has found more offshore reservoirs in the Campeche bay, which contain heavy oils (6-12 ^oAPI). Finding more oil is good news at the times that the production from the super giant oil reservoir of Cantarell reached its maximum production level and starts winding down. The economic implications and technical challenges for the exploitation of the recently found heavy oil resources are highly demanding because of the high viscosities of these fluids (40,000 cp at 15 ^oC) and then the plethora of flow assurance problems that will be generated while producing, transporting, and processing these fluids. Thermal bundled wells will allow an efficient exploitation of these fields.

Heat transfer management achieved through novel and clever thermal design, operation and maintenance of the wells, pipelines and process equipment, maintains the viscosity of the oil at acceptable levels. As to keep an efficient deliverability of the fluid to the surface facilities at the same time that reduces the flow assurance problems, while improves the economics of the exploitation of these fields.

Introduction

Heavy and extra heavy Oil finding are a common occurrence in Mexico these days. PEMEX the government owned Company in Mexico has intensified its searching into deeper waters in the Gulf of Mexico, propelled by increasing prices in the oil & gas world markets, and the increasing hunger for energy resources by Mexico itself.

Mexico has also known of heavy and extra heavy oil in several onshore fields for many years in the past, but because the economics of their exploitation those reservoirs are exploited currently at very low production rates, if they are at all being produced.

Light oil and gas-condensates reservoirs are also being found in the Gulf of Mexico. However, the last drilled exploratory wells at the northern part of the Ku-Maloob-Zaap field shows that heavier oils are there in significant amounts and in not so deep waters (100-200 m). World wide the evidence also shows that is getting more difficult to find Light oils specially in countries like México, Canada, Venezuela and Brazil ^{(1, 2, 3, 4, 5, 6, 7, 8, 9)} – and that the heavy, extra and ultra-heavy oils conform the more abundant resource from now on that should be extracted in the near future.