Increasing Efficiency of Solvent Assisted Cyclic Steam Stimulation of the Bottomhole Formation Zone of a Carbonate Reservoir using Aquathermolysis Catalysts

The global energy sector faces an important task of ensuring the energy security of states. In this regard, oil and gas producing companies need to master and use potentially technologically effective solutions in the development of hard-to-recover reserves (HTR), whose share is on an upward trend. It should be noted that one of the key problems in well production of hydrocarbons is heavy oil with a high content of asphalt-resin-paraffin components. Combined steam cyclic treatments of bottomhole formation zones are the most popular solution, and there are ways to significantly increase their efficiency. The purpose of this study is to substantiate the efficiency of using aquathermolysis catalysts in the implementation of combined cyclic steam stimulation (CSS). In the present article the numerical model was built in the software product for geological and hydrodynamic modeling. The model demonstrates the distribution of high-molecular-weight oil components in the bottomhole formation zone during solvent assisted CSS with and without the use of a molybdenum-based oil-soluble aquathermolysis catalyst and formic acid hydrogen donor. The results obtained show that pre-injection of the catalyst and hydrogen donor contribute to the reduction of high molecular weight components of oil by 1.5 times, while the average daily oil production rate increased by about 4.3 times. This confirms the technological efficiency of the technology under consideration. The obtained relationship between the nature of the distribution of high-molecular components of oil in the bottomhole formation zone and the improvement of reservoir properties has not been previously considered in similar studies.