| Title | Geothermal Wells Discharge Initiation Using Air Lift And Air Compression: Case Study With And Without Downflow In The Wellbore |
|---|---|
| Authors | Bacquet, Alexandre., Situmorang, Jantiur. and Novianto |
| Year | 2014 |
| Conference | New Zealand Geothermal Workshop |
| Keywords | discharge initiation, air compression, air lift, downflow, Sumatra |
| Abstract | During the exploration phase of Rantau Dedap geothermal field located in South Sumatra, Indonesia, 2 wells (namely X-1 and X-2) were drilled from the same pad by Supreme Energy Rantau Dedap (SERD). After respectively 3 and 2 months under shut-in conditions, decision was taken to discharge these wells in order to accelerate the heating-up process. These two wells present similar temperature, but their respective completion tests have shown that a downflow is occurring in the wellbore of well X-1 while it is not the case in well X-2. Furthermore, attempts of simply opening the master valve to discharge these wells were not sufficient, and thus stimulation methods were required to do so. This particular situation gives a good opportunity to assess the effectiveness of the different types of discharge initiation such as air lift and air compression, for wells with and without downflow. This paper describes in details the sequence of operations and the associated well behaviours during the various attempts to discharge wells X-1 and X-2, both using air lift and air compression methods. The results show that improving the procedure for initiating discharge using air compression increased the probability of a successful discharge of the well. In addition, the different attempts on well X-1 raise some concerns about the use of air lift for a well presenting a downflow in its wellbore. Putting into perspective the cost and the operational issues of each of these methods, this paper aims to provide appropriate solutions to initiate well discharge under particular configurations and provides a better methodology to ensure a safe and successful well discharge stimulation. |