Integrated Methodology to Optimizes Production and Performance of Electrosubmersible Pump System in Shushufindi Field

Abstract

Shushufindi is a mature oil producer field located in Ecuador; it was discovered in December 1968. For 20 years was development by foreign oil industry and then was transferred to national oil company. In February 2012 a contract was signed between Petroamazonas and Consorcio Shushufindi. Since this date until now the production has been incremented from 34800 bopd to 75000 bopd. The main Artificial Lift system applied to the field is electro submersible pump (ESP). High water cut, scale, low pressure, gas production, corrosion and other are problems that have presented in the wells affecting the run life of ESP. A Multidisciplinary team has been created to work on a plan to improve the artificial lift system performance and increase production through the application of a monitoring and optimization process. Initially failure frequency was reported due to tubing casing communication, cable failure or motor failure. Therefore some optimization studies on these wells to use 12 and 18 pulses variable speed drive (VSD) instead of 6 pulses in order to minimize the harmonic distortion from the input side of the VSD. Where realize that, it is a common petroleum engineering practice to produce the oil with minimum operating cost, while maintaining the facilities to serve efficiently for its design life time. In the meantime the production rates of the well should be convenient to their capabilities. Any fault in the design of the proper production equipment for each well reduces the equipment life, increase maintenance cost, and workover need and, therefore, increase the total oil production cost. Performance indicators were established to evaluate the performance of electrical submersible pumps from the beginning of the contract. The ESP average run life is 669 days. On 2013 the percentage of indirect failures was 89.3% and direct failures 10.7%. Tubing Casing Communication failure is the most important which represents 49.7%.Actually there are 140 producers wells completed with ESP of which 64% has remote monitoring. Optimization studies on production parameters and operating conditions of ESP are continuously evaluated to perform increase of frequency, amperage consumption optimization, recommended operating range for ESP, downhole equipment replacement, equipment deeping, and others are done in order to increase production and ESP run life.