1. Potassium Silicate Based Drilling Fluids
CAODC
January 30th, 2008

2. Approximate # of Wells Drilled with Silicate Based Fluids since 1998

3. Use in North America Canada Mexico USA
Commonly used in foothills of Alberta and British Columbia
using only potassium silicate
Mexico
steadily used in Southern Mexico
only water based system offering inhibition close to oil based systems
USA
inhibition with HS&E advantages
Used in Colorado & Wyoming as well as OK, TX, LA, WA & AR

4. Sodium/Potassium Silicate Overview

5. Manufacturing Silicate
Heat Energy
Raw Material
Raw Material
steam
Spray dried

6. Soluble Silicate Overview
Silicon is the 2nd most abundant element in the earth’s crust ~28%
Soluble silicates are among the largest volume of synthetic chemicals
World wide volume of sodium silicate is ~4 million tonnes on SiO2 basis
Soluble silicates have been manufactured on an industrial scale since the 1830’s
Soluble silicates are a major class of chemicals finding a wide range of applications in numerous industry sectors
Household detergents
Pulp and paper production
Water treatment
Mining
Soil stabilization
Paints & binders
Cements

7. Silicate Products for Detergents with Typical Uses
Metasilicate (1.0 Ratio)
High alkalinity
Used extensively in: industrial & institutional laundry, steel cleaning, hard surface cleaners
Liquid Silicates (including 2.5 ratio potassium silicate)
Milder alkali buffer
Frequently used in: liquid laundry, consumer spray-dried powder, auto-dish
Spray-dried powder Silicates (2.0 & 2.4 ratio)
Frequently used in: consumer powder laundry, auto-dish
Valfor 100
Mildly alkali (pH 10)
Used primarily in consumer powdered laundry, some carpet freshener and car wash applications.

8. Silicate Drilling Fluids

9. Performance Properties of Silicate based Drilling Fluids
Shale Inhibition
HS & E
Corrosion Control
Better Cementing

10. Health, Safety & Environment

11. Health and Safety
Silicates are one of the oldest and most benign industrial chemicals
Used in a wide variety of applications including water treatment, soil remediation, agriculture etc…)
Silicates are non flammable and contain no VOC’s thus making their use very popular with rig crews
Generally Recognized As Safe by USDA and FDA (GRAS List)
HMIS rating:
health rating -1 (slight)
flammability rating -0 (none)
reactivity rating - 0 (none)
contact rating - 2 (moderate due to pH)
Alkalinity of a silicate drilling fluid is very similar to laundry soap ( i.e.. Both use approximately the same ratio and concentration of silicate)

12. Potassium Silicate Drilling Fluids & Corrosion Control

13. Silicate Drilling Fluids for Corrosion Control
Silicate Corrosion Control:
Protective Silicate Layer on Metal Surface
Low Electrical Conductivity (vs. KCl System)
alkaline pH (~ 11)
Buffers Acid Gas Influxes
Limits Bacterial Degradation
Low Toxicity

14. Silicate Corrosion Control
Alkalinity (pH)
Potassium Silicate (1 – 10 %): pH ~ 11.0
Anode: Fe → Fe e-
Cathode: H+ + 2 e- → H (acidic environment)
Cathode: O2 + 4 H+ + 4 e- → 2 H2O (acidic environment)
Cathode: O2 + 2 H2O + 4 e- → 4 OH- (alkaline environment)
Neutralization of Acid Gases:
Formation of carbonic acid: CO2 + H2O = H2CO3
Neutralization of carbonic acid: H2CO3 + OH- → CO H2O
Neutralization of hydrogen sulfide: H2S + 2 OH- → S2- + H2O
Prevents Bacterial Degradation of Drilling Fluid Additives

15. Electrical Conductivity
Silicate Corrosion Control
Dissolved Salts (Electrical Conductivity)
Drilling Fluid Electrical Conductivity
Potassium Chloride
Potassium Silicate
Electrical Conductivity
(mS.cm-1)
Concentration (%)

16. Corrosion Coupon Testing Silicate Concentration
Field Testing: (British Columbia + Alberta)
Steel Corrosion Coupons (AISI 4130)*
Location: Drill Pipe (Above Collars)
Exposure Time: > 75 h
Calculate Corrosion Rate:
low: 0 – 5 mpy
moderate: 5 – 10 mpy
high: > 10 mpy
Silicate Concentration
Corrosion Rate (mpy)
1 % (volume)
1.3, 1.9
1.9, 3.7
10 % (volume)
1.8
1.2
5 % Potassium Chloride
> 25
* API Recommended Practice: 13B-1

17. Reference Papers

18. SPE Papers on Silicate Based Drilling Fluids
Use of Silicate-Based Drilling Fluids to Mitigate Metal Corrosion
Silicate-Based Fluid, Mud Recovery System Combine to Stabilize Surface Formations of Azeri Wells
Novel Application of Sodium Silicate Fluids Achieves Significant Improvement of the Drilling Efficiency and Reduces the Overall Well Costs by Resolving Borehole Stability Problems in East Africa Shale
Silicate-Based Drilling Fluids Deliver Optimum Shale Inhibition and Wellbore Stability
Exceeding Drilling Performance and Environmental Requirements with Potassium Silicate Based Drilling Fluid
Silicate/Enhanced Low Shear Rate Viscosity (LSRV) Drilling Fluid System and New Drilling Approach in Rang Dong Field
Development of Novel Membrane Efficient Water-Based Drilling Fluids Through Fundamental Understanding of Osmotic Membrane Generation in Shales
Membrane Efficiency in Shale - An Empirical Evaluation of Drilling Fluid Chemistries and Implications for Fluid Design

19. SPE Papers on Silicate Based Drilling Fluids
74378: Novel Application of Ecological System Drilling Fluid Accomplishes Significant Advances in the Hole Stability Problems
67737: Research into Lubricity, Formation Damage Promises to Expand Applications for Silicate
Drilling Fluids
63053: Shale Stabilization by Pressure Propagation Prevention
59751: Use of Silicate Mud to Control Borehole Stability and overpressured Gas Formations in Northeastern British Columbia:
57564: Horizontal Drilling Experience in the Panna Field
39401: New Insight into the Mechanisms of Shale Inhibition using Water Based Silicate Drilling Fluids:
37611: The Use of Silicate-WBM Facilitates Successful Primary Cementation Operations on the BHP Petroleum Liverpool Bay Development:
37266: Silicate Based Muds: Chemical Optimization Based on Field Experience:
35059: Silicate-Based Drilling Fluids: Competent, Cost-effective and Benign Solutions to Wellbore Stability Problems:

20. Other Papers on Silicate Based Drilling Fluids
World Oil, Oct. 1998: Back to the future in silicate drilling fluids
World Oil, April 2003: Drilling fluid and cementing improvements reduced per-ft drilling costs by 10%
AADE -04-DF-HO-29: Sodium Silicate Fluids Improve Drilling Efficiency and Reduce Costs by Resolving Borehole Stability Problems in Atoka Shale
AADE -04-DF-HO-28: Flexible Drilling Formulation and Application
AADE -04-DF-HO-29: Silicate based Drilling Fluids: A Highly Inhibitive Mud System Offering HS&E Benefits Over Traditional Oil Based Muds
AADE-06—DF-HO-40: Next Generation Silicate Technology Reduces Cost and Improves Performance