According to the current prognosis, the total oil production in the mature provinces is expected to decline within a few years. This trend can create a significant gap between hydrocarbon supply and demand in the certain regions of the world. Developing new offshore provinces and unconventional hydrocarbon reserves can reduce this production gap in the future. The IOR methods are also expected to reduce this production gap by bringing advanced technological solutions to boost oil recovery from mature fields, geologically complex low permeable and carbonate reservoirs in the future.
Most of the IOR potential will come from the producing basins by reducing the risk and CAPEX of IOR projects, making the best use of the existing infrastructure and extending the production economic life of the fields. The present paper will review worldwide IOR experiences considering the limitations of the existing infrastructure, market access routes and regional economic framework. The current and future IOR strategies will be discussed.
Environmental aspects are playing now more important role in the evaluation of the IOR strategies. Sequestration of greenhouse gases and developments in the environmentally sensitive offshore areas represent new IOR drivers and challenges in the same time. With the increasing number of the deep-sea developments, the subsea IOR methods will represent new opportunities. Similarities and differences between IOR practices in the Atlantic, Gulf of Mexico and the North Sea will be addressed. The authors will give a comparative review of the IOR methods, their application scale and achieved results to date in different geographies. The importance of screening and evaluation of IOR methods for timely decision on their field application will be emphasised.
The examples from the industry show, that there are excellent opportunities for technology transfer among countries and operators.
Most of the current world oil production comes from mature fields. Increasing oil recovery from the aging resources is a major concern for oil companies and authorities. In addition, the rate of replacement of the produced reserves by new discoveries has been declining steadily in the last decade. Therefore, the increase of the recovery factors from mature fields under primary and secondary production will be critical to meet the growing energy demand in the coming years. Improved Oil Recovery (IOR) methods encompass Enhanced Oil Recovery (EOR) methods as well as new drilling and well technologies, intelligent reservoir management and control, advanced reservoir monitoring techniques and the application of different enhancements of primary and secondary recovery processes.
It is well known that EOR projects have been strongly influenced by economics and crude oil prices. The initiation of EOR projects depends on the preparedness and willingness of investors to manage the EOR risk and economic exposure and the availability of more attractive investment options. In the U.S. chemical and thermal EOR projects have been in constant decline since mid 1980's, with gas injection methods as the preferred recovery methods in the last decade (Figure 1).
