“…With the continuous consumption of conventional reservoir resources, the exploitation of unconventional oil, including heavy oil, has become the key to satisfying human demand for hydrocarbon fuels. − According to statistical estimates, the total amount of recoverable heavy oil is almost equal to the remaining reserves of conventional oil in the world. , Presently, the available production methods are mainly based on thermal methods, such as steam-assisted gravity drainage (SAGD), , cyclic steam stimulation (CSS), , and steam flooding. , However, the large heat loss in the upper and lower rock formations of thin oil reservoirs and the reduction of steam quality in deep oil reservoirs cause the thermal methods to be less effective in improving the recovery rate and lowers economic efficiency. , In recent years, the cyclic solvent injection (CSI) process, also known as Huff-n-Puff, has attracted widespread attention owing to its excellent applicability in thin and deep reservoirs.…”