The paper describes how corrosion engineers can use the decision tree analysis in order to evaluate and select the best materials for the completion of a new oil field, characterised by high CO2 and H2S content.
The method has been based on the decision tree analysis and the Montecarlo simulation to obtain the probability distribution of some events to cccur (for instance, number of workovers, corrosion inhibitor efficiency, coating damage rate). The corrosion study leads to four different technical solutions, showing different risk and reliability: carbon steel with corrosion allowance and inhibitor injection, coated tubing, and two corrosion resistant alloys, a superduplex stainless steel and a superaustenitic stainless steel. The cost comparison has been carried out by using the Expected Monetary Value criterion applied to the Life Cycle Cost evaluation. The paper presents and discusses the decision tree and the results of simulations.
Keywords. Montecarlo Simulation, Corrosion Risk, Life Cycle Cost