Enhanced oil recovery of shallow wells with heavy oil: A case study in electro thermal heating of California oil wells

Abstract

A combination of uncertain oil prices and the shortage of easy to produce oil has led energy companies to look to develop difficult oilfields that in the past would have been considered uneconomic. Even abandoned fields are being reopened with less than ideal recovery methods. It is with this mindset that many energy companies are looking to utilize new technologies or new technology applications to maximize the production of heavy oil wells where production has either decreased dramatically over the years, resulting in fields that — while still having ample reserves — are not considered to be viably economic to produce, or have not been economically viable given heavy oil production costs. Specifically, in California, approximately half of the state's crude oil reserves consist of heavy oil. However, using current or dated technology, less than nine billion barrels of heavy oil have been produced from an original total resource of 77 billion barrels. [3] This paper explores the utilization of Electric Heat Tracing as a viable technology solution to bridge the gap between economic and uneconomic when considering heavy oil wells in the California region wherein production has dropped to an unacceptable level or production is not economically desirable. Historically, specific Electric Heat Tracing technologies have proven to be viable solutions — technically and economically — when considering the maximizing of well—output against the capital costs of new equipment required at the well. Recently, other Electric Heat Tracing technologies, such as Mineral Insulated Heating Cables or Skin-Effect Tracing Systems, have entered the arena of downhole heating or bottom hole heating considerations, providing a much needed solution for the development of the more difficult reservoir conditions. With this mindset, this paper will look at the specific application needs (i.e. heavy oil reservoirs throughout the California region), the available technology solutions with specific emphasis on Electric Heat Tracing, and the expected and realized results through the use of these available technology solutions. Further, this paper will highlight the system requirements for this solution, and the associated cost; with specific emphasis on return on investment when considering capital cost and operating cost expenditures.