Abstract

A total of forty-four hydraulic fracturing jobs using regular sand have been conducted in the Tanjung Raya Field since December 1996, contributing over 5,000 bopd of incremental production. Although the fracturing program was successful, a high number of well services occurred as a result of proppant flowback to the wellbore.

Well failures due to proppant flowback resulted in workover operations on 22 of the 27 fractured wells since 1996, or 0.81 failures per well per year.

This paper will discuss using resin coated sand and compare the results against using regular sand following fracture stimulation. The results of modifications to post fracturing operations will also be discussed.

Hydraulic fracturing with resin coated sand was initiated in the Tanjung Raya Field in early 2000 to reduce the incidence of proppant flowback. However, resin coated sand has been shown to have disadvantages. For example, it is difficult to clean out the wellbore in the event of a screen out. Hydraulic fracturing with resin coated sand has been performed on six wells in Tanjung and has contributed approximately 500 bopd of incremental oil. To date, only one the six wells has required service due to proppant flowback.

To reduce downtime and accelerate closing fracture, force closure procedure has been initiated by flowing back the frac fluid immediately after the frac treatment. This method has reduced down time resulting from workover operations.

Another change in post frac operations has been made in the clean out procedure of the remaining frac sand in the wellbore. Previous common practice of bailing the frac sand has been replaced by circulating the frac fluid out of the wellbore with a macaroni string.

Initial results indicate that resin coated sand is more effective in the Tanjung Raya Field for minimizing proppant flowback and that forced closure has been beneficial. Additional studies will be conducted to determine if there is any reduction in fracture conductivity as a result of using resin coated sand.