Quick Gas Production Increment by Optimization of Pressure Control Valves on Gas Condensate Wells: A Field Case in Saudi Arabia

摘要

Evaluating pressure drop changes across Pressure Control Valves (PCVs) is a key element for identifying potential gas incremental opportunities and determining potential energy loss in maturing gas fields. This is more critical when the gas reservoir is being depleted without a pressure maintenance suport program. A dedicated production tracking and monitoring process is required for a full evaluation of every component in the gas production system; from downhole to the gas plant. Operational data and choke valve erosion velocity calculations from 60 gas producing wells were evaluated to identify PCV's needing replacement and optimize production strategy. These wells were experiencing high PCV pressure drops, constraining their ability to produce at maximum potential. Factors such as Cv; internal damage or plugging were evaluated to determine the cause of the under sized PCV’s. Additional efforts were required to verify the sizes of installed PCV’s and to ensure that flow rates could be properly calculated by recalibration of instrumentation and validation of venturi meter calculations. A PCV replacement program was then established to maximize the productivity of seven (7) critical high producing wells. This paper describes the multi-disciplinary approach and methodology implemented in North Central Ghawar Gas field to optimize the performance of installed gas well pressure control valves. This methodology will continue to be implemented and expanded to cover more than 500 wells in other Saudi Aramco gas fields. The paper discusses additional topics such as: proper design and metallurgy of pressure control valves, new evaluation model for pressure control valve flow equations, gas rate validation, building PCV simulator model using dedicated well performance tools, screening tools and an economic model. Implementing this program is essential to maximizing gas rates and optimizing field production by identifying undersized PCV’s that need to be sent to the shop for internal inspection and maintenance or replacement.