Conformance Control
VEC-1 composition is intended to prepare solutions of the crosslinkable polymer system to process input wells under the technology of permeability and heterogeneity alignment of reservoirs flooding and increase the coverage of the reservoir flooding. EOR technologies can serve as an excellent example.
VEC-1 composition is a synergistic blend of polymers.
When injected into reservoir, solutions based on the VEC-1 composition enter the flooded interlayers, and form gels with a crosslinker, having hydrodynamic resistance sufficient to redistribute the flow and level the injectivity profile.
Water is used as the solvent to prepare the compositions. The following types of water are used: technical, brine, natural.
Mobile unit APZR-P is applied for the preparation and injection of VEC-1 solution with crosslinker, and provides continuousness of the process.
List and Purpose of EOR technologies
№ |
Technologies |
Description |
Sphere of Applications |
Injection Volume, m3/m3/м |
1 |
VEC-1 |
The technology involves the installation of a gel screen acrylamide-based polymers in the near-bottom-hole formation zone in order to align the injectivity profile of injection wells and increase the flooding coverage. The optimal composition of gel-forming composition and its amount are selected for the conditions of every field in order to provide high performance processing. |
Reservoir Type: porous, fractured-porous Permeability: 0.1-1 µm2 Temperature: 20-90 °С Specific injectivity: 30-70 m3/day/
|
VEC-1(or its analogue):10-50 |
2 |
VEC-1+СНК-1 |
Integrated technology includes injection of VEC-1 polymeric gelling composition, followed by treatment of bottom-hole zone with СНК-1 intensifying surfactant composition to restore wells' injectivity and involve low-permeability interlayers in developing the wells. |
Reservoir Type: porous, fractured-porous Permeability: 0.1-1 µm2 Temperature: 20-90 0С Specific injectivity:
30-70 m3/day/m
|
VEC-1 (or its analogue): 10-50
СНК-1: 5-10 |
3 |
СНК-1+VEC-1 +СНК-1 |
The integrated technology is designed to process the low-permeability reservoirs (wells with low permeability). The technology includes three phases: 1) The injection of the СНК-1 intensifying surfactant composition to clear the bottom-hole zone; 2) The injection of VEC-1 for redistribution of filtration flows; 3) The injection of СНК-1 intensifying surfactant composition for better clearing of residual oil. |
Reservoir Type: porous Permeability: 0.1-1µm2 Temperature: 20-90 0С Specific injectivity:
<20 m3/day/m |
СНК-1: 5-10 VEC-1 (or its analogue) : 10-50
СНК-1: 5-10 |
4 |
СНК-1+VEC-1+destructor |
The integrated technology is designed to process the low-permeability reservoirs (wells with low permeability). The technology includes pre-cleaning of bottom-hole zone using an intensifying surfactant СНК-1 composition. After a well’s injection capacity has been increased, VEC-1 composition with good filterability is injected. The final stage includes the processing bottom-hole zone with a destructor to destroy the gel in low-permeability oil interlayers and restore injectivity of the well. |
Reservoir Type: porous, fractured-porous Permeability: 0.1-1 µm2 Temperature: 20-90 0С Specific injectivity:
10-50 m3/day/m
|
СНК-1: 5-10 VEC-1 (or its analogue): 10-50
Destructor: 0.3-3
|
5 |
VEC-2+VEC-1 |
Integrated technology is intended for the treatment of fractured porous reservoir by insulating the fracture system in the bottom-hole zone of the input wells with the help of polymer viscoelastic composition with enhanced strength characteristics, with the subsequent conformance control and filtration flows in heterogeneous porous reservoir using VEC-1. |
Reservoir Type: fractured-porous Permeability: 0.5-2 µm2 Temperature: 20-90 0С Specific injectivity:
50-90 m3/day/m |
VEC-2: 1-5
VEC-1 (or its analogue):10-25 |
6 |
VEC-2+VEC-1+ CКСк (СКСт) |
Bottom-hole zone treatment with СКСк or СКСт compositions is carried out to increase the injectivity of the well after the treatment of fractured-porous reservoirs with VEC-2 + VEC-1 (iss. 5) polymeric gel-forming compositions. The offered acid composition affects the matrix of the bottom-hole hole and connect idle intervals of the reservoir. Предлагаемые кислотные составы воздействуют на матрицу ПЗП и способствуют подключению неработающих интервалов пласта. |
Reservoir Type: fractured-porous Permeability: 0.5-2 µm2 Temperature: 20-90 0С Specific injectivity:
50-90 m3/day/m |
VEC-2:1-5 VEC-1 (or its analogue): 10-30
Acid composition (СКСк or СКСт) |
7 |
VEC-НПЛ+VEC-1 |
Integrated technology of the treatment of fractured porous reservoir includes isolation of the fracture system with VEC-НПЛ followed by alignment of the injectivity profile with composition of VEC-1. VEC-NPL composition contains filler in the form of elastic hydro gel particles that colmatage highly conductive bridging channels, creating a high hydrodynamic resistance in the cracks.
|
Reservoir Type: fractured-porous Permeability: 0.3-2 µm2 Temperature: 20-90 0С Specific injectivity:
40-80 m3/day/m |
VEC-НПЛ: 1-7 VEC-1 (or its analogue):
10-30 |
8 |
ВПК + VEC-1 |
The integrated technology is designed to reduce the permeability and isolation of the existing system of cracks in the bottom-hole zone in the input wells with a composition based on a water-absorbent resin composition (WAC), followed by alignment of the injectivity profile and filtration flows in heterogeneous porous reservoir using VEC-1 composition. |
Reservoir Type: fractured-porous Permeability: 0.3-2 µm2 Temperature: 20-90 °С Specific injectivity:
40-90 m3/day/m |
ВПК: 0.1-0.3 VEC-1 (or its analogue):
10-30 |
9 |
СНК-2 |
The aqueous emulsion-dispersed composition (EDC) is used as a working agent for alignment of permeability and heterogeneity of low-permeability reservoir due to washed hydrophobic layer. EDC is a stable dispersion of liquid hydrocarbon components and reagent SNK-2 with water. |
Reservoir Type: porous Permeability:0.001-0.02 µm2 Temperature: Up to 80 0С Specific injectivity:
5-40 m3/day/m |
СНК-2: 5-10 |
10 |
The redistribution of filtration flows – polymer flooding |
Oil displacement with polymer solutions is an effective method of enhancing oil recovery by increasing the coverage of water flooding in volume (through the redistribution of flows of varying permeability interlayers) and area (due to the increase in resistance in the most permeable interlayers), as well as due to increased displacement efficiency.
The development of polymer flooding technology for specific field conditions is carried out on the basis of the complex physical and chemical, filtration research and mathematical modeling. |
Reservoir Type: porous Permeability: 0.01-0.1 µm2 Temperature: ≤90 0С Specific injectivity:
10-50 m3/day/m |
20-30% Vpores |
11 |
ПАПС |
This method is applied, both in early and late stages of fields development. Specially selected surface-active compounds with without polyacrylamide for the specific conditions of terrigenous reservoir provide increased displacement efficiency due to ultra-low interfacial tension (below 0.005 mN / m) of aqueous solutions of these compositions, on the border with the oil and increase coverage of reservoir flooding by equalizing the mobility of polymer-surfactant formulations (PAF) with the mobility of the displaced oil. As a result, the final oil recovery is increased for not less than 15% (abs.) at a later stage fields flooding.
This method is tested on
the fields of terrigenous and carbonate reservoirs. It is effective to
implement the cyclic injection of PAFP and water. |
Reservoir Type: Porous and slightly-fractured, terrigenous or carbonate Permeability:>0.001 µm2 Temperature: ≤90 °С Specific injectivity: 10-50 m3/day/m Oil viscosity:
<50 mPa*s |
5-30% Vpores МР or PAFP
30% Vpores PAFP composition |
Note:
This table is not a guidance document but is for informational purposes only. Each technology (ies) is (are) selected, tested and adapted in special laboratories, in accordance with the actual geological and physical characteristics of the object. After a series of experiments, physical and mathematical modeling, technological instruction or regulation of the industrial introduction of the selected technologies are developed. Selection and adaptation of technology and technical documentation is conducted in several process steps:
1) Collection and analysis of geological and physical data, selection of the optimal industrial area for the impact;
2) Pre-selection of the composition according to the actual characteristics of the object;
3) Experimental verification of correctness of the choice;
4) The physical (filtration laboratory) and mathematical (a series of calculations, involvement of software) modeling;
5) Calculation of target technical efficiency of the implementation of the selected technologies on the object in question;
6) Final recommendations
(regulations, tech. instruction) to industrial implementation of technologies
mentioned above.