Kinetics of Heat Generating Chemicals Used for Improving Oil Recovery; a Case Study for the Removal of Condensate Banking

Condensate banking represents a challenging problem in producing hydrocarbon from light gas reservoirs. Formation of condensate bank are as a result of pressure during depletion. The accumulation of liquid condensates around the production well can significantly impair the gas flow rate. Condensate accumulation in the vicinity of the gas well is known to curtail hydrocarbon production by up to 80%. Numerous approaches are being employed to mitigate condensate damage and improve productivity in the reservoir. Chemical treatment, gas cycling and hydraulic fracturing are the most effective technique for combating the condensate bank. The chemical method of Enhanced oil recovery can be used to reduce condensate development and accumulation in the reservoir by maintaining the reservoir pressure. The application of thermofluids to recover more oil as a result of increase in pressure and generation of heat to re-evaporate the condensed oil within the well bore radius. Sodium Nitrite and Ammonium Chloride are the most widely used thermochemicals in the oil and gas industry. Experiments were conducted on varying concentrations. The kinetics of this reaction when activated with acids or acid precursors were the subject of this work. The effect of the catalyst (acid concentration) was found to influence reaction rate. Further research was carried out on the thermofluids stating the functional groups present, hydrophilic and hydrophobic components in the thermochemicals in order to enhance future research options. Ultimately, this research is centered on the reaction mechanism (which indicates the pressure, temperature and reaction time). The kinetics of the reaction showed an attractive performance due to the heat generated, functioning the same way as injection of steam/ heat during thermal recovery process and thus can be used in place for thermal recovery. The pressure generated during the reaction can also be utilized in the reservoir as a pressure maintenance technique and as well curtail the condensate formation.