7/28/2019 Brinedril Vis

1/1

2008 Halliburton

Divalent Brine Sweep withBRINEDRIL-VIS Viscosifier Proves Efficient and Cost-effective in a Coiled TubingCleanout

Location: High Island Area, Gulf of Mexico

OPERATORS CHALLENGE

Immediately after the gravel pack operations in a Gulf of Mexico well, problems developed trying to shift the sleeveand reverse gravel pack sand out of the well. A decisionwas made to rig down the frac lines and run coiled tubingfor a cleanout procedure.

The operator was running 1.5 coiled tubing to a depth of 6,790 inside of 3.5 drill pipe. To rid the pipe of sand, highviscosity hydroxyethyl cellulose (HEC) sweeps were run.The HEC sweeps were effective, but the larger portion of gravel pack sand was seen following the tail end of theHEC sweeps due largely to the lower pump ratesachievable with the high viscosity of the HEC polymer.

HALLIBURTONS SOLUTION

To increase the efficiency of removing excess frac sandfrom the gravel pack assembly, BRINEDRIL-VISviscosifier was used in a divalent brine as a sweepingagent to deliver both viscosity and suspension. Theobjective of using BRINEDRIL-VIS viscosifier was to

increase the carrying capacity of gravel pack sand whilekeeping fluid viscosity, pump pressure and excess drag toa minimum. Halliburton Baroid personnel mixed a 10 barrel(bbl) sweep using a formulation of 2.5 lb/bbl (25 lb) in theHalliburton Cement Unit. The sweep was sheared usingthe cement units centrifugal pump with a resulting funnelviscosity recorded at 95 sec/qt.

Divalent Brine Sweep

www.halliburton.com/baroid

Once the coil tagged bottom, the BRINEDRIL-VIS sweewas circulated down the coiled tubing, up the coiled tubiannulus and out of the well at a rate of 1.0 bbl/min. Theaverage pump pressure was only 6,450 psi, compared toan average pump pressure of 6,900 psi for a HEC sweep the same quantity. The BRINEDRIL-VIS sweep containlarge amounts of fine particles and gravel pack sand thatwere in suspension of the sample. While the HEC sweephad unloaded gravel pack sand, sand particles seemed tofall to the bottom of the sample cup within seconds.

Impressed by the BRINEDRIL-VIS viscosifier suspensiocharacteristics and annular velocities, the operator decideto displace the entire circulating system with 60 bbl of thBRINEDRIL-VIS fluid before pulling out of the hole.Following the sweeps, the well fluid exhibited no visual of solids with 14 nephelometric turbidity units (NTU)readings. This cleanout was successful, allowing theoperator to reach the packer with ease.

ECONOMIC VALUE CREATED

The BRINEDRIL-VIS fluid sweep proved to have anincreased carrying capacity, decreased down hole pressuand was actually more cost effective at 2.5 lb/bbl than HEmaterial. The BRINEDRIL-VIS sweeps improved efficiewhich resulted in eliminating time to wash out excessgravel pack sand down to the packer and saved additionaoperational cost.