Optimizing Clean Out Proppant Methods After Premature Screen Out Fracturing Job Telikota Field, Central Sumatera Basin
Authors: Nataliawati Nurul Ayu , Yogasugama Mario Andre , Kurniawan Imron Fajar , Higuita Riantana Pinem , Prasetio Mario Hadinata , Salim Jimmy , Hamdani Nanang Lutfi 
Published: October 2023

Fracturing has become a key enabler in the success of exploiting the Low Reservoir Quality (LQR) of Telikota field since the start of optimization campaign in 2018 and recent infill drilling in 2021 which using fracturing as a main Initial Completion (IC) objective. One of key success component of the typical IC fracturing job is the clean out proppant after the main fracturing job completed.

In the case when premature screen out occurs, a specific treatment must be conducted to ensure the remaining proppant in string can be cleaned up before proceeding to another step. In the last 10 years, several methods were used in Telikota field, which includes clean out using macaroni pipe, clean out using CTU and the most recent method, direct stripping & clean out method.

When a fract job is prematurely screened out, the proppant is filling up the tubing string, in an extreme case the whole tubing filled fully with proppant. Up to 10 years ago, 1-3/4″ R2 macaroni pipe was run into the tubing to perform the clean out. A more recent practice was by deploying Coiled Tubing Unit, with a set of CTU BHA consisting of motor and nozzle, was run to perform the clean out. Currently, a more time efficient and more effective method was developed, called direct stripping & clean out method. The procedure for this method is by unseating the fract packer and stripping out the fract tubing immediately without performing reverse circulate out proppant. Big challenge is struggle with more than three-quarters volume tubing fill full of gel proppant. The key enabler to perform this method is the use of specific type of packer fract and the ability to apply pressure in annulus during the unseating process.

There were several reasons that the clean out job no longer uses a set of macaroni pipes, but the main concern is safety issue since there were several cases of personal injury during handling macaroni pipe. Using coiled tubing is the main clean out sand method until 2021, and this is a very reliable method in terms of effectiveness compared to macaroni pipe. However, due to a steep ramped up of the well intervention activity in the block including fracturing and other stimulation operation, the readiness of coiled tubing unit become an issue and the 2 (two) fleets of CTU was outnumbered.

Solution of this problem then came up and developed a new method called direct stripping & clean out method. This method was effectively executed and turned out to be the first choice of method in case of premature screen out. Additional time and cost required for this method is way lower compared to the other 2 (two) methods mentioned above. Another benefit is the simplicity of this method since there is no need to run a small pipe inside the fract tubing.

The goal of this paper is to provide direct comparison of several methods for clean out proppant post a premature screen out event in hydraulic fracturing job.