Hydrophobic Shale Inhibitor (ME-Nfshield)
COMPOSITION / INFORMATION ON INGREDIENTS AND APPLICATIONS
ME-Nfshield is a surfactant-treated nano-silica with hydrophobic properties and high reactivity. It increases the shale surface contact angle and decreases the free energy of the shale surface, which results in effective hydration inhibition. In comparison, other shale inhibitors, such as Glycol Amine, do not achieve the same level of shale surface contact angle. ME-Nfshield strongly adsorbs onto the shale surface, plugging the pores and reducing water flow, which provides effective inhibition of shale hydration.
ME-Nfshield demonstrates excellent shale inhibition performance while maintaining good compatibility with ME-Poly FL Control Agent. After aging, the Apparent Viscosity (AV) and Plastic Viscosity (PV) remain stable even at high temperatures. When 3% ME-Nfshield is added to the initial fluid, it improves shale inhibition and increases the cutting rolling recovery to 93%.
This nano hydrophobic anti-collapsing and shale inhibitor effectively reduces the free energy of the rock surface, decreases the filtrate wetting of the rock surface, and inhibits shale hydration. The nano hydrophobic anti-collapsing agent adsorbs onto the rock surface to form a hydrophobic film, significantly increasing the contact angle of the rock surface. This reduces the surface free energy of the shale, thereby inhibiting hydration. The positive electrical properties of ME-Nfshield attract negatively charged clay particles, compressing the double electric layer and further inhibiting clay hydration.
1#: Add 1% ME-Nfshield and remove Polyamine
2#: Add 1% ME-Nfshield and remove Polyamine, and reduce 3% KCl, reduce 4% salt
By adding ME-Nfshield, it can help maintain a high level of shale inhibition despite removing Polyamine or reducing KCl or salt.
(1) High temperature tolerate- Size Effected data
|
Tem(℃) |
D50(nm) |
|
25 |
371 |
|
120 |
349 |
|
150 |
259 |
|
180 |
190 |
|
200 |
255 |
|
220 |
235 |
The particle size of the sealant has no change , after 150-220℃ aging, the particle size of the sealant is concentrated between 190 and 400 nm . Due to the fracture of a small number of molecular bonds, the size is slightly reduced, but it can still maintain a good size distribution.
(2) Thermal stability--Thermogravi metric analysis
The thermal weight experiments show that the dissociation temperiture starts at
315 °C, has good thermal stability.
Thermogravi metric curve
At room tem to about 108 ° C , the mass loss rate is 7 . 4% , which is caused by the volatilization of free water;
Between 108 to 315°C, the mass loss rate is 8%, which is caused by the fracture of side base;
From 315℃ ~447℃ , the mass loss rate is
73.2%, which is because of degradation of the polymer molecular backbone causeing a sharp decline of the mass;
When the tem climbs to 447℃ , the thermal
degradation of the polymer molecular is finished.
