The main difference of OBM from water based solutions is a non-polar dispersion medium.
Application of ERUO
- ERD wells (big hole wells - a big departure from the vertical), HS.
- Complex geological and technical drilling conditions:
- 1. high downhole temperatures and pressures;
- 2. deposits with a high content of H2S;
- 3. extended clay intervals, anhydrite, salt deposits (including carnale, bischofite);
- 4. debris and collapses of unstable shale;
- 5. drilling in conditions of anapd with the presence of salts in the section.
- Dissection of productive strata;
- Exploratory drilling with coring to determine natural water saturation;
- Technological liquids for killing wells, blocking packs, cattle / IRS, etc.
Main advantages:
- High quality opening of the reservoir due to the similar properties of oil and EROO
- Low penetration of the filtrate into the reservoir and minimal impact of the filtrate on the reservoir properties
- Highest inhibition of clays, resistance to salts, hydrogen sulfide, etc.
- Reuse of drilling mud
- No corrosion
- Low friction coefficient
The main disadvantages are:
- fire and explosion hazard
- density and viscosity depend significantly on pressure and temperature
Practical use:
Mikhailovsky field. Considering the reservoir temperature of the Mikhailovsky field (about 30º C), low viscosity oil with a kinematic viscosity of not more than 7 cSt will be used as the basis for preparation.
Benefits of application:
- Reuse
- Relative environmental friendliness (4th grade)
- Primary and secondary (development) dissection of the reservoir
NeoInvert Oil – oil for the preparation of ERUO
Low viscosity oil for use in low downhole temperatures
| Indicator | Norm | Result |
|
Appearance |
Transparent, low-viscosity, no sediment |
Complies |
|
Flash point in open crucible, ° С, not less |
80 |
83 |
|
Pour point, ° С, not higher |
— 35 |
— 40 |
|
Density at 20 ° С, kg / m3, not more than |
900 |
841 |
|
Kinematic viscosity at 40 ° С, not more |
7,00 |
4,19 |
*The use of diesel fuel is possible, but the flash point is reduced to 60 ° C and the hazard class of the solution is reduced to 3.
NeoInvert Mod — ERU rheology modifier
Regulation of rheological properties for high-quality cleaning of horizontal trunks
Benefits:
- Increase DNS and SNS;
- Increased sedimentation and thermal stability of the drilling fluid;
- Providing viscosity at low shear rates (VNSS);
- Leveling the temperature-rheological profile of an OMR (reduction of the difference in viscosity at the bottomhole and surface).
The composition of the drilling fluid
| Component | Function |
% |
|
NeoInvert Oil |
Low viscosity oil (kinematics <7 cSt) |
70-80 |
|
Водный раствор CaCl2 |
mineralized water phase |
20-30 |
|
NeoInvert К |
Complex emulsifier |
2-3 |
|
NeoInvert Mod |
Rheological modifier |
0,5-2 |
|
NeoInvert FL Liquide |
Filter reducer |
1-2 |
|
NeoInvert GF |
Surfactant-water-repellent solid phase |
0,2-1 |
|
Карбонат кальция |
Acid soluble weighting agent |
payment |
|
NeoInvert Bent |
Organobentonite |
1-2 |
Calculation of volumes for Mikhailovskaya
|
VOLUME OF DRILLING SOLUTION |
||||||||
|
п/п |
Interval type |
from |
to |
L, m |
D, m |
Cavern. |
V, m3 |
|
|
1 |
Operational |
— |
1 526 |
1 526 |
152,0 |
1,00 |
28 |
|
|
2 |
Open trunk |
1 526 |
1 729 |
203 |
146,0 |
1,05 |
4 |
|
|
3 |
Well volume at the end of drilling |
32 |
||||||
|
4 |
Minimum surface volume |
70 |
||||||
|
5 |
The volume of the solution in the circulation at the end of the drilling interval |
102 |
||||||
|
6 |
Calculation of drilling fluid loss: |
|
||||||
|
|
6.1. |
Permeable reservoir filtration (infiltration) |
1 |
|||||
|
|
6.2. |
Losses on the cleaning system |
Loss ratio, m3 / m3 |
1,00 |
4 |
|||
|
|
6.3. |
On dilution |
Dilution ratio, m3 / m3 |
— |
— |
|||
|
|
6.4. |
Technological losses (core, IPT, siphon, spill, etc.) |
3 |
|||||
|
|
6.5. |
Total loss of drilling mud |
8 |
|||||
|
7 |
Required volume of drilling fluid per drilling interval |
110 |
||||||
|
8 |
The resulting solution from the previous interval / well * |
— |
||||||
|
9 |
Fresh drilling fluid volume |
110 |
||||||
|
10 |
The volume of solution for disposal / discharge to the barn / transfer or storage |
109 |
||||||
|
11 |
Drilled rock volume |
Decompression ratio |
1,00 |
4 |
||||
|
12 |
Total drilling waste (OBR + BSH) |
112 |
||||||
|
|
Emergency drilling fluid volume |
23 |
||||||
*On the 2nd and subsequent wells it is possible to use 80-90 m3 of the EROO from the first well. It is necessary to preserve the volume as much as possible after the completion of the well construction.
Well cost calculation
|
Calculating the cost of providing services for engineering support of drilling fluids |
|||||
|
p/p |
Name |
unit of measurement |
quantity |
Price per unit, rubles without VAT |
Cost, rubles without VAT |
|
1 |
Chemical reagents and materials |
skv. |
1 |
11 476 800,0 |
11 476 800,0 |
|
2 |
Process Engineer, Wagon House, PKL |
day |
8 |
12 000,0 |
96 000,0 |
|
3 |
Dispersant EROW |
day |
8 |
12 000,0 |
96 000,0 |
|
4 |
Sieve Panels |
things |
0 |
— |
— |
|
5 |
Mobilization |
RUB/t |
156,05 |
2 710,0 |
422 895,5 |
|
6 |
Demobilization |
RUB/t |
33,40 |
2 710,0 |
90 514,0 |
|
Total cost of providing services, rubles without VAT |
12 182 209,5 |
||||
|
VAT 20% |
2 436 441,9 |
||||
|
Total cost, rubles with VAT |
14 618 651,4 |
||||