OPTA-VerT

CORE OPTA-VERT SYSTEM COMPONENTS
OPTA-VERT
drill-in fluids are custom designed to provide
minimal reservoir damage over a wide range of
porosities and permeabilities, whilst at the same
time providing an easily removable filtercake on
drawdown.
FEATURES AND BENEFITS
• Non-damaging – low skin values, high return permeability.
•Negligible lift-off pressures required – for rapid cleanup.
• Ultra-low-permeability filtercake – low leak off and stuck pipe mitigation.
• Highly inhibitive.
• Low friction factors.
• Reduced remediation costs.
PRODUCT
FUNCTION
GENERIC CHEMISTRY
CONFI-MUL P
Primary emulsifier
Primary emulsifier
CONFI-MUL S
Secondary emulsifier
Secondary emulsifier
CONFI-GEL / CONFI-GEL HT
Viscosifier
Organophilic bentonite
CONFI-MOD
Low end rheology modifier
Dimer / Trimer acid
OPTA-CARB
Custom sized bridging agent
Calcium carbonate
OPTA-MUL
2 in 1 emulsifier for low mud weighting
Primary and secondary emulsifier
TYPICAL FORMULATION AND PROPERTIES OF AN OPTA-VERT SYSTEM
PRODUCT BASE
OPTA-VERT
PROPERTIESDYNAMIC AGING 16
HOURS @ 275 ºF
FLUID0.65
Density (lb/gal)9.1
Drillwater (bbl/bbl)0.12
PV (cP)26
Calcium Chloride (lb/bbl)15
YP (lb/100 ft2)21
CONFI-MUL P (lb/bbl)
6–8
6 RPM13
CONFI-MUL S (lb/bbl)
3–4
ES (Volts)1040
CONFI-GEL (lb/bbl)
4–6
OWR85:15
CONFI-GEL HT (lb/bbl)
2–4
Excess Lime (lb/bbl)4
CONFI-TROL HT (lb/bbl)
6–8
HTHP (500 psi, 275 ºF)
<4
Lime (lb/bbl)10
The system is custom designed for each individual reservoir
and uses a range of high-quality components and design
tools to facilitate the design process. One such tool is the
HyPR-SIZER software programme that allows the fluids
engineer to optimise the concentration and particle size
distribution of the bridging agent to ensure solids are
deposited across the pore throats with minimum invasion,
while sealing off the reservoir with a thin, compact and
resilient filtercake.
OPTA-VERT is recommended for reservoir drill-in and
coring applications with a raised potential for problems,
e.g. emulsion blocking, associated with water-based drill-in
fluids. Problems minimised by OPTA-VERT include:
• Wellbore instability caused by hydratable shales above
The result – a system that provides strong benefits as a
high-performance, non-damaging drill-in fluid that optimises
production rates across a wide range of completion methods:
• Open-hole gravel-pack or non-gravel-pack completions
• Expandable slotted screen completions
• Slotted or perforated liner completions
• Cased-hole completions where hole cleaning
or minimising fluid invasion is critical
The OPTA-VERT system delivers all of the characteristics
required of a drilling fluid being highly inhibitive and ideally
suited to drilling interbedded reservoirs with shale.
The OPTA-VERT system is naturally lubricious making it an
ideal choice for horizontal wells.
•Fluid instability related to high bottom hole
The OPTA-VERT system’s non-damaging properties are evident
both in the laboratory and in the field when initial production
figures are compared to the reservoir’s anticipated production.
•Excessive torque and drag related to high-angle and
EMULSION BLOCKING IN A RESERVOIR
or interbedded with reservoir sands
temperatures
extended reach drilling
OPTA-CARB (Ib/bbl)
10 – 55 (As required)
RETURN PERMEABILITY FOR THREE OPTA-VERT FORMULATIONS AGAINST +/- 1000 md CLASHACH SANDSTONE
OPERATIONAL PORE VOLUME
SEQUENCE
(cc)
FILTRATE LOSS
BASE OIL ON APPLYING PERM (md)
THE DRILLING
MUD (ml)
OIL PERMEABILITY
AFTER DRAWDOWN
AT 800 PSI (md)
(% CHANGE ON BASE PERM)
11.2 lb/gal
11.657
OPTA-VERT
(Sample A) drilling mud
followed by drawdown
to dead crude oil
5.117
935
(0.439 PV)
813
(-13.0%)
11.2 lb/gal
9.792
OPTA-VERT
(Sample B) drilling mud
followed by drawdown
to dead crude oil
4.432
984
(0.453 PV)
935
(-4.98%)
11.2 lb/gal
11.568
OPTA-VERT
(Sample C) drilling mud
followed by drawdown
to dead crude oil
3.923 947
(0.339 PV)
900
(-4.96%)
NON-AQUEOUS SYSTEMS