This document describes the results of experiments testing a potassium hydroxide (KOH) and ViNUM-ACRE clay stabilization system. The system aims to permanently stabilize clays using KOH at a concentration of 15 parts per billion, adjusted to a pH of 9-10 with ViNUM-ACRE. Test results show the system inhibits swelling of bentonite clays even at high clay concentrations, and recovers over 90% of shale in a hot rolling test. Rheology measurements indicate the treated fluid has good viscosity and yield properties for drilling applications.

1. K-TRON SYSTEM
LABORATORY EXPERIENCE

2. BACKGROUNDBACKGROUND
KOH (potassium hydroxide) clay stabilization results from the interaction of caustic
with the clay in the presence of potassium ions.
The KOH-clay chemical reaction permanently alters the clay chemistry so that the
clay minerals are unaffected by changes in water composition.
There are many technologies available for stabilizing clays, but KOH remains the
only means of stabilizing clays permanently a significant distance into the formationonly means of stabilizing clays permanently a significant distance into the formation
The KOH reacts chemically with clays, rendering them invulnerable to
destabilization through swelling or migration.
This reaction should be distinguished from technologies that stabilize clays
temporarily, such as KCl (potassium chloride), or coating clays with surfactants or
polymers
Predominant clays in treated formations have been kaolinite, illite, migrating clays,
chlorite and smectite, swelling clays.
Use the proper chemical concentrations. KOH is effective at high concentrations,
usually 15 - 30 percent by weight.

3. TREATMENT MECHANISMTREATMENT MECHANISM
A synergistic effect involving irreversible caustic/sandstone interaction in the
presence of potassium ions (K+) promotes permanent KOH clay stabilization.
Potassium ions alone (e.g. KCl) do temporarily stabilize clays, as long as the clays arePotassium ions alone (e.g. KCl) do temporarily stabilize clays, as long as the clays are
in contact with an appropriate potassium-ion-containing treatment fluid.
The synergistic clay-stabilization effect of potassium ions in the presence of
hydroxide ions results from irreversible caustic/sandstone interaction that locks in the
stabilization effect of potassium ions. Potassium ions quickly and temporarily stabilize
clays during a KOH treatment. The hydroxide ions slowly lock in place the beneficial
potassium-ion effect.

4. TWO MECHANISMSTWO MECHANISMS
First : the irreversible caustic/sandstone interaction partially dissolves clays and sand
grains at exposed surfaces. Partial dissolution results in breaking silicon/oxygen
chemical bonds that then reform in a more favorable manner.
The stable chemical rearrangement results in chemically bonding migratable clay
particles to sandstone pore walls and in chemically bonding together interstitial layers
of swelling clay particles.of swelling clay particles.
Second: a small amount of new potassium-aluminosilicate material (possibly a
potassium zeolite) is precipitated over the clays. The precipitate prevents fresh water
from contacting the clays and cements migratable clay particles to the pore walls.
Clays such as pure montmorillonite or kaolilite, are often near-quantitatively converted
to potassium zeolites when placed in concentrated KOH solutions at elevated
temperature for extended periods.
Potassium zeolites are aluminosilicate minerals that do not contribute to fresh water
induced permeability damage if formed within sandstone pore bodies.
KOH stabilization at 185°F (85°C)

5. NEW CLAY FORMATIONNEW CLAY FORMATION
SAMPLE 1 2
TAP WATER (ml) 350 350
KOH (g) 50
MIXING TIME (min) 5 5

6. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2
BENTONITE (g) 10 10
MIXING TIME (min) 15 15
OBSERVATION LOW VISC LOW VISC
RHEOLOGY @ 120 °F
600 RPM ND ND
300 RPM ND ND
PV ND ND
YP ND ND
GELS ND ND

7. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2
BENTONITE (g) 10 10
BENTONITE CONCENTRATION (ppb) 20 20
MIXING TIME (min) 15 15
OBSERVATION MEDIUM VISCOSITY SEPARATION OF BENTONITE
ON BOTTOMON BOTTOM
RHEOLOGY @ 120 °F
600 RPM 28 ND
300 RPM 22 ND
PV 6 ND
YP 16 ND
GELS 13/17 ND

8. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2
BENTONITE (g) 10 10
BENTONITE CONCENTRATION (ppb) 30 30
MIXING TIME (min) 15 15
OBSERVATION High viscosity SEPARATION OF BENTONITE
ON BOTTOM
High viscosity
ON BOTTOM
RHEOLOGY @ 120 °F
600 RPM 86 ND
300 RPM 77 ND
PV 9 ND
YP 68 ND
GELS 47/63 ND

9. CLAY RECOVERYCLAY RECOVERY
API FILTRATE 2
BENTONITE (g) 10
BENTONITE CONCENTRATION (ppb) 30
MIXING TIME (min) 15
OBSERVATION SEPARATION OF BENTONITE ON BOTTOM
FILTRATE CAKE OF NEW K-CLAY
DRYING CAKE IN OVEN
TAP WATER EXPOSITION THE CAKE DOES NOT SWELL OR
DISPERSED

10. K-CLAY
SAMPLES AFTER FIVE MONTH

13. KOHKOH CONCENTRATIONCONCENTRATION
SAMPLE 1 2 3
TAP WATER (ml) 350 350 350
KOH (gr) 5 15 30
MIXING TIME (min) 5 5 5
BENTONITE (g) 10 10 10
MIXING TIME (min) 15 15 15
OBSERVATION PHASES
SEPARATION
PHASES
SEPARATION
PHASES
SEPARATION

14. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2 3
BENTONITE (g) 10 10 10
MIXING TIME (min) 15 15 15
OBSERVATION PHASES SEPARATION PHASES SEPARATION PHASES SEPARATION
RHEOLOGY @ 120 °F
600 RPM ND ND ND
300 RPM ND ND ND
PV ND ND ND
YP ND ND ND
GELS ND ND ND

15. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2 3
BENTONITE (g) 10 10 10
BENTONITE CONCENTRATION (ppb) 20 20 20
MIXING TIME (min) 15 15 15
PHASES PHASES PHASES
OBSERVATION SEPARATION SEPARATION SEPARATION
RHEOLOGY @ 120 °F
600 RPM ND ND ND
300 RPM ND ND ND
PV ND ND ND
YP ND ND ND
GELS ND ND ND

16. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2 3
BENTONITE (g) 10 10 10
BENTONITE CONCENTRATION (ppb) 30 30 30
MIXING TIME (min) 15 15 15
OBSERVATION GEL
PHASES
SEPARATION
PHASES
SEPARATIONOBSERVATION GEL SEPARATION SEPARATION
RHEOLOGY @ 120 °F
600 RPM 13 ND ND
300 RPM 10 ND ND
PV 3 ND ND
YP 7 ND ND
GELS 5/6 ND ND

17. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2 3
BENTONITE (g) 10 10 10
BENTONITE CONCENTRATION (ppb) 40 40 40
MIXING TIME (min) 15 15 15
OBSERVATION GEL
PHASES
SEPARATION
PHASES
SEPARATIONOBSERVATION GEL SEPARATION SEPARATION
RHEOLOGY @ 120 °F
600 RPM 25 ND ND
300 RPM 22 ND ND
PV 3 ND ND
YP 19 ND ND
GELS 12/10 ND ND

18. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2 3
BENTONITE (g) 10 10 10
BENTONITE CONCENTRATION (ppb) 50 50 50
MIXING TIME (min) 15 15 15
OBSERVATION GEL
PHASES
SEPARATION
PHASES
SEPARATIONOBSERVATION GEL SEPARATION SEPARATION
RHEOLOGY @ 120 °F
600 RPM 43 ND ND
300 RPM 39 ND ND
PV 4 ND ND
YP 35 ND ND
GELS 26/11 ND ND

19. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2 3
BENTONITE (g) 10 10 10
BENTONITE CONCENTRATION (ppb) 60 60 60
MIXING TIME (min) 15 15 15
OBSERVATION PASTE GEL
PHASES
SEPARATIONOBSERVATION PASTE GEL SEPARATION
RHEOLOGY @ 120 °F
600 RPM ND 10 ND
300 RPM ND 8 ND
PV ND 2 ND
YP ND 6 ND
GELS ND 4/5 ND

20. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2 3
BENTONITE (g) 10 10
BENTONITE CONCENTRATION (ppb) 70 70
MIXING TIME (min) 15 15
OBSERVATION GEL
PHASES
SEPARATIONOBSERVATION GEL SEPARATION
RHEOLOGY @ 120 °F
600 RPM 18 ND
300 RPM 15 ND
PV 3 ND
YP 12 ND
GELS 7/9 ND

21. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2 3
BENTONITE (g) 10 10
BENTONITE CONCENTRATION (ppb) 80 80
MIXING TIME (min) 15 15
OBSERVATION GEL GELOBSERVATION GEL GEL
RHEOLOGY @ 120 °F
600 RPM 26 15
300 RPM 23 12
PV 3 3
YP 20 9
GELS 11/12 6/7

22. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2 3
BENTONITE (g) 10 10
BENTONITE CONCENTRATION (ppb) 90 90
MIXING TIME (min) 15 15
OBSERVATION GEL GELOBSERVATION GEL GEL
RHEOLOGY @ 120 °F
600 RPM 42 21
300 RPM 39 18
PV 3 3
YP 36 15
GELS 15/15 7/7

23. RHEOLOGICAL RESPONSE TORHEOLOGICAL RESPONSE TO
COLLOIDAL LOADCOLLOIDAL LOAD
SAMPLE 1 2 3
BENTONITE (g) 10 10
BENTONITE CONCENTRATION (ppb) 100 100
MIXING TIME (min) 15 15
OBSERVATION
GEL GELOBSERVATION
GEL GEL
RHEOLOGY @ 120 °F
600 RPM 69 32
300 RPM 59 28
PV 10 4
YP 49 24
GELS 25/23 8/9

24. RHEOLOGY @ 5 PPBRHEOLOGY @ 5 PPB KOHKOH

25. RHEOLOGY @ 15 PPBRHEOLOGY @ 15 PPB KOHKOH

26. RHEOLOGY @ 30 PPBRHEOLOGY @ 30 PPB KOHKOH

27. COMPARATIVE RHEOLOGYCOMPARATIVE RHEOLOGY

28. REMARKABLESREMARKABLES
1. The results of rheological response to clay load show that at potassium
hydroxide concentration from 15 ppb is sufficient to inhibit the swelling of
active clay like API bentonite.
2. Argillaceous loads up to 100 ppb loads can be added to fresh water without
causing dramatic increases in the rheological values.
3. Can be expected drilling hydratable clay that fluids containing from 15 ppb of
KOH can provide sufficient inhibition to prevent phenomena of swelling and
dispersion.

29. VINUMVINUM--ACREACRE
ViNUM-ACRE is a natural product used in the food industry and
pharmacology for its neutralizing properties and controlling the pH of
stomach pH and buffer action in the intestinal tract.stomach pH and buffer action in the intestinal tract.
ViNUM-ACRE is a natural acid substance that can be combined with KOH to
reduce pH and create potassium source highly inhibitory.

30. BACKGROUNDBACKGROUNDpH OPTIMIZATION
SAMPLE 1
TAP WATER (ml) 350
KOH (g) 15
MIXING TIME (min) 5
pH 13.5
ViNUM-ACRE (ml) 85
pH 11.8

31. SAMPLE 1
XCD (g) 1.3
MIXING TIME (ml) 30
OBSERVATION LOW FOAM
D-FOAM (ml) 3D-FOAM (ml) 3
MIXING TIME (ml) 15
BARITE (g) 40
REV DUST (g) 20
MIXING TIME (ml) 15
OBSERVATION NO FOAM

32. SHALE RECOVERY TESTSHALE RECOVERY TEST
CAMPBELL SPECIMEN weight (g) 10.39
HOT ROLLED @ 250°F, 18 hours
5.9
pH
Adjust pH
9.0
Weight, Sieve (g)
87.65
Weight, Sieve plus CAMPBELL (g)
97.14
Weight, CAMPBELL (g)
9.49
% Shale Recovery 91%

33. KOHKOH//VINUMVINUM--ACRE SYSTEMACRE SYSTEM
SAMPLE 1
TAP WATER (ml) 350
KOH (g) 15
MIXING TIME (min) 5
VINUM-ACRE (ml) 45.5
pH 9.4
XCD (g) 1.5
MIXING TIME (ml) 30
OBSERVATION Some foam
D-FOAM (ml) 1
VI-STARCH (g) 3
MIXING TIME (ml) 30

34. CALCIUM CARBONATE (g) 40
REV DUST (g) 20
MIXING TIME (ml) 15
pH 8.9
pH WANTED 9-10
KOH (g) 0.05
pH 9.4

35. SAMPLE
1
CAMPBELL SPECIMEN WEIGHT (g)
10.53
HOT ROLLED @ 250°F, 18 hours
FOAM
noFOAM
MIXING TIME (min)
15
pH
8.7
Adjust pH
9.7
Weight, Sieve (g) 87.23
Weight, Sieve plus CAMPBELL (g) 97.29
Weight, CAMPBELL (g) 10.06
% Shale Recovery 95

36. RHEOLOGYRHEOLOGY
RHEOLOGY @ 120 F BHR AHR
600 RPM 33 31
300 RPM 25 25
6 RPM 8 96 RPM 8 9
3 RPM 7 7
PV 8 6
YP 17 19
GELS 6/8 7/8
LSYP 6 5

37. LUBRICITYLUBRICITY
CORRECTION FACTOR 0.988
Coefficient of Friction @ 5 min 0.304
Coefficient of Friction @ 10 min 0.280
Coefficient of Friction @ 15 min 0.259
L-20 LUBE (ml) 18
MIXING TIME (min) 15MIXING TIME (min) 15
FOAM yes
D-FOAMER (ml) 2
pH 6.5
ADJUST pH 9.7
CORRECTION FACTOR 0.988 % REDUCTION
Coefficient of Friction @ 5 min 0.152 50.0
Coefficient of Friction @ 10 min 0.150 46.4
Coefficient of Friction @ 15 min 0.142 45.2

38. API FILTRATEAPI FILTRATE
API FILTRATION (ml/30 min) 2.5
CAKE QUALITY filmCAKE QUALITY film
CAKE THICKNESS (mm) <1

39. REMARKABLESREMARKABLES
1. We have developed a system based KOH with range of controlled pH (9-10)
2. The system combines the stabilizing action of alkaline solutions of KOH in a range of
10-15 ppb with the neutralizing effect of food and fertilizer grade acids which are
generators of efficient shale stabilizer as potassium salts.
3. Xanthan gum is used in a concentration between 1-1.5 ppb
4. Starch is used for filtrate control at concentration between 3-5 ppb
5. Calcium carbonate is an excellent bridging agent at concentration of 40-50 ppb
6. L-20 LUB can be used to improve lubricity at concentration from 3 to 5% (v/v).
7. D-foam agents must be used for foam control when L-20 is the lubricant additive.
8. The shale recovery after rolling at 250°F is more than 90%