Title : Clay reactivity with brine and its impact on fluid flow through porous media
Abstract:
Brine sensitivity of clay bearing formations have been the focus of oil and gas industry for several years. The formations bearing clay showed a formation damage and reduction in permeability when brine of altered properties became in contact with the clay. The previous led to the study of the effect of various parameters on clay and brine reactivity and the impact on fluid flow through porous media. It was found that the main results of clay and brine reactivity were fines migration and flocculation, clay swelling and wettability alteration.
Clay swelling was early recognized as the major cause for formation damage and permeability reduction in clay bearing formations especially near wellbore region as well as a source for wellbore instability in drilling operations.
Later, clay fine migration was introduced as another mechanism of formation damage and permeability reduction as well as a problem for surface production facilities. However, mixed-wet fines migration was found to be beneficial due to the participation of mixed-wet fines in increasing oil recovery and sweep efficiency when compared with its associated permeability reduction.
Finally, the wettability alteration due to brine and clay reactivity could be seen from different perspectives depending on the type of the wettability alteration. mixed-wettability and water-wettability are favored on oil-wettability since they generally increase oil recovery, sweep efficiency and relative fluid mobility through porous media.
This paper studied deeply the effect of various parameters affecting clay and brine reactivity such as salinity, pH, flow rate, temperature, type and valence of cations, anions, oil presence as well as the clay type and concentration on clay fine migration and flocculation. Moreover, the effect of salinity, temperature, pressure, type and valence of cations, anions as well as the clay type and concentration on clay swelling is also analyzed. Finally, the effects of pH, salinity, oil presence as well as oil properties, type and valence of cations, anions, temperature, pressure and clay type and concentration on wettability alteration of clays and clay bearing formations were investigated too.
Audience Take Away:
- The audience should be able to choose the appropriate brine composition used in waterflooding operations of clay bearing formations to avoid potential formation damage and increase the oil recovery.
- The audience should be able to understand the effect of clay/brine reactivity on fine migration and its impact on fluid flow through porous media and on oil recovery.
- The audience should be able to analyze the effect of clay/brine reactivity on clay swelling and its impact on fluid flow through porous media.
- The audience should be able to investigate the effect of clay/brine reactivity on wettability alteration and its impact on fluid flow through porous media.
- The audience should be able to understand the contribution of different parameters on the clay/brine reaction rate and the resultant of that reaction.
- This will help reservoir engineers in developing a better design for the brine being used in waterflooding operations of clay bearing formations by understanding the mechanism of reaction between the brine and clay and its impact on fluid flow through media and eventually oil recovery.
- It will allow the reservoir engineers to avoid potential formation damages that could be triggered by choosing a poor design of the brine composition used in waterflooding operations.
- It highlights the benefit of mixed-wet fine migration showing that it could be beneficial from the standpoint of increasing the ultimate oil recovery.
- Yes, this research will help other faculties to expand their research and teaching. There are many research groups that are interested in the topic of waterflooding with different brine salinities such as LowSal. Hence, this research will be very beneficial in understanding how the salinity of different brines affects the clay stability and fluid flow through porous media along with other parameters included in the research.
- This research also could be used as an excellent material in any reservoir engineering course at any university.
- Yes, it provides a practical solution for producing from reservoirs with clay bearing zones using waterflooding as a secondary recovery technique. As it gives the designer the option to choose the proper brine composition in waterflooding operations depending on the amount and type of clay in the formation.
- This research allows the designer to avoid the common pitfalls and misunderstandings associated with clay/brine reactivity.
- It allows the designer to maximize the gain from the waterflooding operation by adjusting the parameters that favors the results that he is seeking from the operation.
- Yes, it will help to improve the accuracy of waterflooding projects significantly.
- This research is the first one to combine all the aspects of brine and clay reactivity on fluid flow through porous media as in the past the clay brine reactivity was mainly viewed from the point of formation damage due to swelling.
- That isn’t the only case, and it has come to our knowledge that fine migration of mixed-wet clays could be beneficial in increase the ultimate oil recovery.
- This research could be used as a general guideline and a review for clay/brine reactivity and the impact of several parameters on that reaction.
- This research is very good in describing the basic and simple physics that is responsible for such reactions which gives the engineer the fundamentals behind certain phenomena.
- This research opens the door for future quantification of the combined effect of fine migration, clay swelling and wettability alteration on fluid flow through porous media and ultimate oil recovered.
