PAULSSON, INC. — Department of Energy SBIR Phase I: 20b

Description

Our aim is to increase low oil level recoveries from tight shale formations by designing formation-specific water chemistries that simultaneously minimize oil reservoir adhesion and frac water usage- Tight shale formations in North America contain billions of barrels of oil, however, the industry average recovery is typically well below 10%, especially compared to an average of 30% for conventional reservoirs- Battle Born Algorithms will develop an algorithm that predicts salinity-driven imbibition in tight formations so that fracking fluids can be precisely tailored to produce more oil through a combination of osmotic countercurrent imbibition and wettability alteration- The work will be done in conjunction with researchers from Sandia National Laboratories who have worked out frac water chemistry controls over wettability alteration in tight formations- Tight formations imbibe frac water through capillary and osmotic effects where it displaces oil into fractures and interbeds with large pores and low capillary pressure- The extent of imbibition, and the amount of oil recovered, depends on the osmotic pull of water into the system and wettability alteration-the degree to which the frac water decreases oil-reservoir adhesion and draws water into pores and pushed oil out- For example, dilutefracfluidswillbemorestronglyimbibedintohypersalinereservoirsbecauseofthegreater osmotic pressure difference thus producing more oil- However, lower salinities might result in greater oil adhesion, reducing oil mobility and recovery- Conversely, use of more concentrated fluids will reduce counterflow but enhance oil mobility by decreasing adhesion-The idea is that both osmotic and adhesion forces must be known to design a frac fluid that maximizes oil recovery- A major benefit of an optimized water composition would be reduction of fracking demands for freshwater-