This customer's gas wells produced sporadically, then zoomed down to near-zero production. The situation was cured by Reef field services, GRS-1030, a gas well production enhancer, and Iron-Out, an iron sulfide remover.

Customer:
Major oil and gas company with subject well(s) in Leon County, Texas, Pearwood field

Pertinent well data:
Zone: Cotton Valley Lime Reef  Perforations: 14,757’ - 15,200’ Casing: 7" Tubing: 3 1/2" Monobore Lift type: Flowing

Problem:
The well's gas production was very sporadic with an eventual steep decline to near zero production. Severe iron sulfide with fluid loading was highly probable. Prior mechanical attempts using coiled tubing with motorized bits and separate chemical clean-out applications were unsuccessful for the iron sulfide remediation and fluid recovery. Dense iron sulfide plugs and water loading was identified during this process.

Production prior to workover: 
Gas MCF: 25 MCFD  Condensate: 0 BCPD  Water: < 1 BWPD

Recommendations:
Reef Services was asked to make a recommendation to remediate the iron sulfide problem and restore production. Reef was awarded the opportunity to treat the problems after several mechanical and other chemical attempts for remediation had failed. Reef recommended a combination treatment consisting of: GRS-1030, gas well production enhancer, to aid in the removal of water blockage and scale and Iron-Out, iron sulfide removal system, to breakdown large aggregate deposits of iron sulfide. The application of Reef’s products were:

1. RU coiled tubing unit.
2. Reef products were pumped via coiled tubing as follows: First, 500 gallons GRS-1030 (AI-265 corrosion inhibitor and AF-5020 multifunctional foamer added). Second, 330 gallons Iron-Out (mixed in 2,670 gallons of 2% KCL Water for total Iron-Out solution of 3,000 gallons). Third, flush to the packer using nitrogen.
3. SI overnight, flowed to a working pit the next day to allow for well clean-up.
4. Return to production.

Production after workover:
Gas production increased immediately to 4,625 MCFD. Water production increased to 36 bwpd. After 75 days the stabilized results were: Gas MCF: 3,500 MCFD Condensate: 0 Water: 16.9 BWPD

Summary:
Payout occurred within 12 hours. Currently, 4 wells have been treated with a similar treatment – all with similar results. There are plans for added treatments using GRS-1030 / Iron-Out combination for the same and different zones of interest.