Impact of Production Strategy on Production Forecasting, Energy Demand, and Carbon Emissions: Typical Case Study of the Brazilian Presalt

Abstract

This study evaluates how the production strategy influences the main decision-making indicators in the development of the production of a Brazilian presalt field, considering reservoir and production system models integrated into a single simulation. The general methodology involves the evaluation of alternative production strategies for a case study related to a production development project, from the point of view of reservoirs for the water injection recovery mechanism. Variables with a focus on the reservoir, production, and primary processing of fluids are included. Sensitivity analyses based on the methodology of the response surface of parameters and variables are performed in relation to oil recovery, financial return, energy demand, and carbon emission. Production and fluid injection curves are compared. The integrated modeling (reservoir, well, and processing) was important to evaluate the impact of the selection of the design and management variables of the integrated production strategy, showing the interdependence between the simulated models. The first-order analysis of the uncertain reservoir parameters observed a significant impact on the indicators of field recovery (up to 11%) and financial return (up to 13%), and a lower impact on energy demand (up to 7%), carbon emissions (up to 6%), and oil production per CO2 emitted (up to 4%). The design and management variables of the field (platform capacity, number of producer and injector wells, separation operating pressure, and maintenance pressure in the reservoir), including those related to the production system (platform process plant alternatives for gas recycling, gas turbine-driven compressors, primary separator operating pressure, and production control of the wells to limit CO2 emission) have a significant impact on the indicators of financial return (up to 10% without CO2 emission tax rate, up to 12% with emission tax rate), energy demand (up to 17%), carbon emissions (up to 15%), and oil production per CO2 emitted (up to 15%), with less impact on field recovery (up to 11%). The study quantifies the impact of production strategy variables in an integrated way, especially those related to the production system. This assessment is important for production forecasting and decision-making support on energy demand and greenhouse gas emissions from oil and gas production and processing.