The importance of produced water re-injection (PWRI) is unquestionable. It is in many cases the cheapest and most environmentally friendly solution for wastewater disposal. It is also a feasible method for EOR as a water flooding mechanism.
PWRI, however, suffers from a major limitation, which is the current inability in accurately predicting the lifespan and performance of its injection wells. This is due to the multitude of parameters that affect it. Current models 1-2 exist that incorporate the thermal effects 3 of PWRI leading to fracture growth. However, the leak-off pattern of this injection differs from that of clean water (seawater) injection due to the damage caused by the produced water onto the formation and especially the fracture faces. Thus, static filtration experiments with refined post-mortem analysis have been conducted to obtain quantitative deposition profiles along the core. This allows for the testing and verification of existing models 4-7.
The post-mortem analysis introduced in this paper will be used for future dynamic filtration experiments as well as experiments specifically devised to simulate the fracture tip area. A unified model that will accurately reproduce the permeability decline and deposition profile for all three sets of experiments will flow, thus advancing the predictability of injectivity decline associated with PWRI.