Maximizing Asset Value Through Unified Gas Injection and Gas Export Management Via Development and Adoption of Integrated Well and Process Automation

Abstract

Abstract In oilfield with significant gas production, either from high associated gas production or non-associated gas (NAG) wells, gas injection is often prioritized due to the aim of oil production sustainability compared to gas export, with only the remaining gas flow not taken by the injection wells is exported as sales gas. However, with gas emerging as a cleaner energy source as compared to oil and instability in oil price, higher gas demand is expected in the future. Due to this, flexibility in managing the allocation between gas injection and gas export would be an advantage, especially with the cyclical demand peak due to winter and summer seasons. A case study for optimization for a unified management and automation of the gas export and gas injection is presented in this paper, which includes the flexibility in prioritizing either utilization options and managing the impact of changes in injection gas supply accordingly via process control and automation. With the adoption of new controllers, operator would now be able to choose which priority mode would be given considering subsurface injection and gas export requirements. For example, when priority is given to the gas injection as per current operating mode, only the remaining gas balance will be used for export. However, when gas export is prioritized, operator would have the option to set the minimum gas export flow that is required, and the control system will automatically control the allocation for sales and injection, including automatically calculating and assigning the injection gas flow to each injector wells when the resulting gas injection supply is changed as a result of gas export prioritization. With the automation exercise, the operator would not need to conduct the manual adjustment of choke valves opening to regulate the gas injection and gas export flow, rather only the usage mode prioritization and the desired flow setpoints for both cases are required. The scheme allows the operator to take advantage on the opportunity of prioritizing gas export or injection depending on prevailing market demand and operational requirement needs for maximizing the value from the field.