Empirical Study of Thermochemical for Heavy Oil in Production Wells

The ‘X’ well is an oil well located in South Sumatra, Indonesia, the well began production (on stream) in June 2017 and is still in production today. Fluid characteristics of heavy oil with a value of 24.6 ºAPI and a high pour point of 48ºC originating from the Talang Akar Formation reservoir. The analysis problem shut-in well after two months of production, and the results of laboratory analysis of oil samples are oils with asphalts problems so that the oil freezes before it reaches the surface. The analysis is carried out in the production well has been done twice with a chemical injection of xylene (C8H10) + toluene (C7H8) and the 'X' well is back in production for 9 days but has decreased oil production by 16% per day until the 'X' well shut-in on 18 January 2018, due to indications of heavy oil deposits in production tubing. Based on data from the EMR (Electric Memory Recorder) starting at a depth of 400 m from the surface the temperature is below the pour point (48ºC) of oil produced. On July 22, 2018, a thermal stimulation project with thermochemical by injecting (HCl 15% + NH3 5% + Ester) was carried out to overcome the asphaltenes problem in the 'X' well.  Thermochemical stimulation succeeded in turning on the 'X' well with Qoi 325 BOPD and raising the wellhead temperature from 30ºC / 86ºF to 50ºC / 122ºF for 100 days and then production lasts  58 BOPD  for 120 days. This research was successful in handling production problems at a mature oil field for 230 days  (almost 8 months) economically and can  operate at low oil price  conditions