- A high temperature stabilizer for polymer suspensions
DESCRIPTION
Thermasal is a two component thermal
extender for most polymer based drilling, completion and workover
fluids. Two primary mechanisms for polymer degradation (exemplified
by rapid decrease in fluid viscosity) are: 1. Oxidation reduction
reactions resulting in free radical formation, and 2. Acid
hydrolysis. Thermasal is designed to
prevent these reactions with a synergistic blend of a reducing
agent to retard the formation, at elevated temperatures, of free
radicals and an alkaline earth oxide to buffer pH.
The two components of Thermasal
are:
- Thermasal-A- an anhydrous salt
antioxidant. (Packaged in 50 lb cans)
- Thermasal-B- a fine grind magnesia
compound. (Packaged in 50 lb or 25 kg sacks)
Thermasal may be used in brines such as
sodium chloride, potassium chloride, sodium bromide, sodium
formate, potassium formate, and cesium formate.
APPLICATIONS
Thermasal provides stabilized
rheological and filtration properties at temperatures above 250°F
for polymer suspensions which are formulated with sized, bridging
and/or weighting solids. The addition of Thermasal to brine systems containing sized
calcium carbonate or sodium chloride particles extends the thermal
limit to 300°F and 325°F, respectively.
VISCOSITY COMPARISON OF CALCIUM CARBONATE
FORMULATIONS MIXED IN VARIOUS BRINES UTILIZING THERMASAL
|
10.0 lb/gal NaCl (bbl)
|
0.96
|
--
|
--
|
|
9.0 lb/gal NaCl (bbl)
|
--
|
0.96
|
--
|
|
3% KCl (bbl)
|
--
|
--
|
0.96
|
|
Xanthan Biopolymer (lb/bbl)
|
1.25
|
1.25
|
1.25
|
|
FL-7 Plus®
(lb/bbl)
|
3.75
|
3.75
|
3.75
|
|
Polytex AHT (lb/bbl)
|
4.2
|
4.2
|
4.2
|
|
Thermasal-A (lb/bbl)
|
2
|
2
|
2
|
|
Thermasal-B (lb/bbl)
|
3
|
3
|
3
|
|
Ultra Carb 12 (lb/bbl)
|
35
|
35
|
35
|
| Properties, Initial and 16 Hours Static Age at
300°F |
Initial |
Aged* |
Initial |
Aged* |
Initial |
Aged* |
|
Plastic Viscosity, (cP)
|
38
|
35
|
25
|
24
|
23
|
20
|
|
Yield Point (lb/100 ft 2)
|
47
|
41
|
46
|
40
|
38
|
30
|
|
Gel Strength (lb/100 ft 2)
|
13/18
|
16/20
|
12/17
|
12/13
|
11/15
|
8/9
|
|
LSRV (cP)
|
0.0636 sec -1
|
39,000
|
49,200
|
32,300
|
26,800
|
29,900
|
11,700
|
VISCOSITY STABILIZATION OF A SIZED
SODIUM CHLORIDE PARTICLE FORMULATION UTILIZING THERMASAL
|
10.0 lb/gal NaCl (bbl)
|
0.91
|
0.91
|
|
Xanthan Biopolymer (lb/bbl)
|
1.25
|
1.25
|
|
FL-7 Plus (lb/bbl)
|
3.75
|
3.75
|
|
Polytex AHT (lb/bbl)
|
4.2
|
4.2
|
|
Thermasal-
A (lb/bbl)
|
--
|
2.5
|
|
Thermasal-B (lb/bbl)
|
3
|
3
|
|
Ultrasal™ 20 (lb/bbl)
|
66
|
66
|
| Properties, Initial and 16 Hours Hot Rolled at
300°F |
Initial |
Hot Roll* |
Initial |
Hot Roll* |
|
Plastic Viscosity (cP)
|
48
|
18
|
50
|
43
|
|
Yield Point (lb/100 ft 2)
|
68
|
11
|
65
|
46
|
|
Gel Strength (lb/100 ft 2)
|
16/21
|
1/1
|
16/21
|
16/19
|
|
LSRV (cP)
|
0.0636 sec -1
|
48,500
|
2,200
|
48,500
|
34,300
|
* Viscosities were recorded at ambient temperature after
aging.