2K7 Biocide For Hydraulic Fracturing Fluid Applications
The control of bacteria in reservoirs, wellbores and production systems continues to be a challenge in North America due to high fluid volume hydraulic fracturing. Introducing high volumes of foreign fluids into a new well that haven’t been evaluated for bacterial load and treated appropriately can initiate downhole biofilms that may never be fully eradicated throughout the life of the well.
These microbes can cause damage such as souring of the formation or microbial influenced corrosion (MIC), which can be carried throughout an entire gathering system affecting treating and system integrity.
Fracturing source fluids can be fresh water, produced water, flowback or a combination thereof. OSP’s 2K7 biocide is effective in a wide range of salinities and has a high tolerance for suspended solids, which can accumulate when recycling flowback. This makes 2K7 biocide particularly effective for hydraulic fracturing programs.
2K7 Biocide is effective in:
- High salt and high hardness
- High suspended solids
- Anionic and cationic systems
- Varying viscosities
- Any water/oil ratio
- Recycled fluids
2K7 Biocide will not:
- Crosslink and polymerize friction reducers
- Polymerize or destabilize lubricants and inhibitors
- Sequester iron or generate insoluble sulfides
- Alter fluid viscosities or rheology profiles
- Film out on proppant
Simplified diagram of wellsite fracturing fluid flow and where to use OSP’s LifeCheck Test Kits and 2K7 biocide, as well as downstream applications.
2K7 Biocide Treatment Program
An effective biocide program for hydraulic fracturing takes into account bacterial growth conditions at surface to ensure fracturing system fluid stability, as well as downhole control for reservoir protection.
The OSP LifeCheck ATP Planktonic Test Kit quantifies the initial bacteria load in source fluids in less than 10 minutes. Based on these results, and an understanding of the formation conditions, OSP can recommend a 2K7 biocide dosage to be applied. If fluids are pretreated, LifeCheck ATP can be used to confirm treatment effectiveness prior to water usage.
Once a dosage is determined, 2K7 biocide can be applied via Water Soluble Paks (WSP) into open top frac fluid holding tanks or as a liquid with 2K7 Solution on-the-fly during the fracturing operations.
Approximate 2K7 biocide treatment equivalents
|2K7 Biocide||Volume of Fluid||Treatment Level|
|1 WSP (1 kg/2.2 lb)||10 m3/63 bbl||100 ppm|
|7 WSP (7 kg/15.4 lb)||70 m3/440 bbl||100 ppm|
|1 box WSP (25 kg/55 lb)||250 m3/1,575 bbl||100 ppm|
|1 Drum Solution (220 kg/485 lb)||220 m3/1,385 bbl||100 ppm|
|1 Tote Solution (1,115 kg/2,458 lb)||1,115 m3/7,015 bbl||100 ppm|
To determine program effectiveness post-frac, or to make changes to subsequent application dosages as source fluids change, the LifeCheck ATP Test Kit can be used on-site for fast, effective bacterial load monitoring.