The article considers the problem of determining the economically optimal number of wells for oil and gas fields under production constraints without optimization of oil recovery rate. Similar problems may arise if there is a point of sale of products in the immediate vicinity of the field, as well as in some other cases. The technical and economic model of the process is based on an exponential model of potential well production decline, adjusted for the presence of infrastructural restrictions on production. The analysis of the model showed the possibility of reducing the dimension of the problem to two dimensionless variables - the dimensionless cost of well construction and the dimensionless recovery rate. In this case, the optimal number of wells is described by the dimensionless value of the filling factor of a constant production rate. The optimization problem was solved for a wide range of control parameters, the pessimistic boundaries of which are determined by the development profitability, the optimistic ones – by the maximum indicators for the industry. The solution is presented in graphical form and in the form of an analytical expression for the correlation of the optimal number of wells versus the dimensionless well construction cost and dimensionless recovery rate. It is shown that the presence of restrictions on the rate of extraction reduces the sensitivity of the optimal number of wells to variations in productivity, the cost of well construction and net-back oil prices compared to the optimal values in the absence of restrictions on the recovery rate. In addition, the deterioration of technical and economic conditions - a decrease in productivity and net-back oil prices, an increase in the cost of well construction - leads to a decrease in the optimal number of wells and a reduction in the duration of the period of a constant rate of production. The results of the work can be used when performing analytical assessments of the sensitivity of design solutions for the development of fields remote from the infrastructure of pipeline transport or facilities that support the production levels of large fields.
References
1. Tokunaga H., Hise B.R., A method to determine optimum well spacing, SPE-1673-MS, 1966, DOI: https://doi.org/10.2118/1673-MS
2. Khasanov M.M., Ushmaev O., Nekhaev S., Karamutdinova D., The optimal parameters for oil field development (In Russ.), SPE-162089-MS, 2012,
DOI: https://doi.org/10.2118/201987-MS
3. Апасов Р.Т., Бадгутдинов Р.Р., Варавва А.И. et al., Estimation of optimal parameters for gas field development system (In Russ.), Нефтяное хозяйство = Oil Industry, 2021, no. 12, pp. 74–78, DOI: https://doi.org/10.24887/0028-2448-2021-12-74-78
4. Arps J.J., Analysis of decline curve, Trans. AIME, 1945, pp. 228-247, DOI:10.2118/945228-G
5. Xiao-Hui Wu, Linfeng B., Kalla S., Effective parametrization for reliable reservoir performance predictions, International Journal for Uncertainty Quantification, 2012, V. 2, no. 3, pp. 259–278, DOI: 10.1615/Int.J.UncertaintyQuantification.2012003765
