Evaluation of using Smart Water to enhance oil recovery from Norwegian Continental Shelf sandstone reservoirs.

Master's thesis in Petroleum engineering.Recently, the scale of studies on smart water – one of EOR method - has increased. From decades, water flooding is one of the most used methods to increase oil recovery. However, more effective in sandstone reservoirs is injecting low salinity brine. Due to changing wettability, improved oil mobility in pores can be reached. The studies show, that the significant increase of oil recovery might be achieved. Main objective of the thesis is to answer the question: Can “smart water” be used to enhance oil recovery from targeted fields? The thesis contains theoretical part and practical solution proposals for some of sandstone fields. In order to evaluate possibility of using smart water method on these fields, decision making scheme is presented. The initial wettability of the reservoir rocks will be estimated. Data from these fields will be presented and discussed in term of low-salinity waterflooding. Field P-1 was determined as a good candidate for low-salinity waterflooding, due to its mixed-wet initial state. However to improve oil recovery, the alternation of wettability has to occur. Main obstacle, that may negatively affect “smart water” EOR method is high reservoir temperature. Lack of needed data from field V-1 induces large uncertainty in evaluation process. The initial wettability of the field V-1 has been established as mixed-wet, but this conclusion requires some assumptions. More accurate data could allow to determine if the field may be used for “smart water” flooding