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About IDEC IDEC is committed to providing “local solutions for local drilling needs” and offers solutions and services in Drilling & Completion Fluids, Solids Control & Waste Management, Wellbore Cleanup, Transportation Services, Production Chemicals, and Technical Testing & Analysis Services. IDEC has a history of 12 years of oilfield service experience managing operations in UAE, Iraq, Kurdistan, Turkey, South Sudan, Kenya, Tanzania, and Uganda. IDEC is committed to the growth of its customers, people, and operations – aggressively managing capital and making numerous acquisitions to broaden and extend its service and equipment portfolio. IDEC through its long-term service agreement with a leading Drilling Fluids manufacturer has very strong technical support which gives IDEC and consequently our customers an added degree of reassurance that we understand the region, its economics, and its petroleum market.
MMO History In 19871, the first patent was issued and the first field trial took place using mixed-metal hydroxide (MMH) in a drilling fluids application. Since then, these novel fluids have undergone significant improvements with respect to fluid performance and stability, most notably the introduction of mixed-metal oxide (MMO) chemistry. These "mixed-metal" products are added to a water-based fluid along with clay, such as bentonite, attapulgite, or sepiolite, to produce a unique thixotropic, shear-thinning fluid that is highly viscous at low shear rates but becomes very thin at high shear rates and easily passes through fine screens. Early applications for the use of MMH fluids were targeted for use in unconsolidated formations and for milling operations due to the fluids unique flow profile and superior carrying capacity, Item 2 Fits Gen. MMH Annular velocity profile of a Mixed-Metal drilling fluid The first-generation, mixed metal hydroxides (MMH) were the most sensitive of the MMO systems – prone to contamination and field challenges coupled with cost. The MMH system led the way to the later generations of MMO fluids, including those used nowadays which are more stable systems with much less challenges in the field and higher chances of success. Second Gen. MMH II Better Design Third Gen. MMO MMO Inhabited 2 Evolution of Mixed Metal technology
Features and Applications • Features • Highly shear thinning • Exceptional hole cleaning and suspension • Improved solids removal efficiency vs. competitive systems • Zero flow at wellbore face • Low reservoir damage and easy cleanup • System stable to ~400°F • Viscosity easily destroyed (e.g., for displacement procedures) • Cost-effective vs. polymer muds • High LC50 numbers • Applications • Unconsolidated formations • Loss zones (porous and fractured) • Milling • Horizontal open hole completions • Stabilizing surface holds against collapse • Coiled tubing drilling • Deepwater • High ROPs
What the DrillSmooth System is: TheDrillSmooth systemisaunique, water-baseddrillingfluiddevelopedforfractured and stabilizingmechanicallyweakorpoorlyconsolidatedformations and drilling high-angleorhorizontalwells Basic makeup Complementary Additives • ID-MMO FL fluid loss control additive • Temperature stabilizers (ID-PTS) • AS-Y Shale inhibitor • Selected ancillary products • Weight material • Non-treated bentonite • MMO mixed metal oxide • Water • Soda ash • Caustic soda
DRILLSMOOTH System—What’s in It and How Does It Work What is the DRILSMOOTHsystem? The DRILSMOOTH fluid system is composed of a mixed-metal oxide, which exists as very small, flat particles, typically 0.05 microns in diameter, making it smaller than bentonite. The metals are aluminum and magnesium. It is an inert, white powder that is virtually insoluble in water. It is nontoxic and contains no heavy metals. What is so special about ID-MMO FL fluid-loss additive? ID-MMO FL fluid-loss additive has been carefully and specifically developed for use in the DRILLSMOOTH system. It is a very effective fluid-loss reducer, has good temperature stability and is resistant to degradation by bacteria and enzymes. Conventional fluid-loss reducing additives are usually anionic in nature and, as such, cause the loss of the unique rheological characteristics of the DRILLSMOOTH system. This is especially true with freshly mixed fluid. How does DRILLSMOOTH fluid provide viscosity? The crystal structure of DRILLSMOOTH fluid has an excess of positive charges, which are balanced by chloride ions on the surface. When dispersed in water and added to prehydrated bentonite, the cationic DRILLSMOOTH particles are strongly attracted to the cation exchange sites on the basal surfaces of the clay, forming a strong DRILLSMOOTH -bentonite complex with dramatically increased viscosity.
System Description What is MMO? A small cationic crystal . . . • A dimension smaller than a bentonite platelet (face dimension ~0.05 m) • Flat with high specific surface area (narrow edge of ~0.0008 m) • Charge density 6 to 7 times that of a bentonite platelet • Acid soluble • “Synthesized Structure”
System Description Attachment of the MMO crystal to the bentonite platelet produces an entirely new chemical structure PV is very low YP, Fann 6 and 3, and gels are abnormally high The gels are formed by electrostatic attraction - which is why they are instant but fragile New Adduct Formed by Chemical Reaction
DrillSmoothMechanism Bentonite/MMO complex Bentonite platelet - - - + + + - + + - - - - - + + + + - - - - - - - + + + + - + - - - + + + + + - + - + - - - + + + + + + Bentonite platelet with negative faces. Edge charges are pH-dependent. DrillSmooth crystals: The positive charge due to electron-deficient lattice + + Electrostatic interactions lead to a network of bentonite/DrillSmooth complexes which impart a thixotropic nature to the fluid. + + + 1 micron
DrillSmooth Mechanism The mixed-metal oxide comprising the core of me system has an electron-deficient lattice, and when added to -water, the DrillSmoothparticles bond to the cation exchange sites on bentonite, forming a strong complex, which in turn structures the fluid and provides viscosity and gels. This complex also renders the system relatively insensitive to common contaminants. When the MMO crystals are added to a suspension of bentonite platelets, the cationic crystals displace the naturally "resident" sodium or other cations and form strong associations with the anionic sites on the faces of the clay plates. What results is a new complex or adduct with fundamentally different characteristics from those of a virgin bentonite platelet. The entire mechanism appears to be electrostatic in nature, which makes it somewhat unusual and accounts for the unique characteristics of the fluid system. For example, an electrostatic field-based mechanism could explain the elastic or deformable-solid behavior observed in the absence of shear and could also explain both the dramatic and instantaneous onset of the solid to-liquid transition and the reversibility of the process.
Newtonian Flow Non-Newtonian Flow Velocity Profile Hypothesized Flow Profile The flow profile of the fluid in the annulus affords DrlllSmooth the ability to stabilize mechanically weak and poorly consolidated formations. The high viscosity of the fluid at low shear rates results in a stationary layer of fluid on the sides of the wellbore. This protective layer shields weak rock formations from erosion caused by the flow. The capacity of the fluid to stabilize these weak and unconsolidated formations is further enhanced by the lower pump rates used with the DrillSmooth system. This tendency may also explain the lower seepage losses that occurred in several wells in which the formations -were fractured. Stationary, gelled layer of mud • Zero shear-stress at wall • Minimal dynamic fluid loss • Protects poorly consolidated or fractured formations • Helps prevent seepage losses • No erosion of wellbore Excellent cuttings transport
The Rheology of MMO (Mixed Metal Oxide) Systems The Fig illustrates the shear thinning behavior of MMO systems. In high-shear regimes at the bit, around heavy weight drillpipe and inside the drillpipe, the effective viscosity of all the fluids are very similar and very low. Circulating pressures and pressure losses are minimized and bit horse power is maximized for maximum rates of penetration. Conversely, in the low-shear-rate regime, such as in the annulus, Mixed Metal Oxide, more than other water-based drilling fluid systems, has a higher effective viscosity, that leads to more effective cuttings carrying capacity and hole cleaning efficiency. Shear-thinning properties of Mixed Metal Oxide Fluids Systems
Formation Damage Characteristics Formation damage is a condition that impairs the permeability of reservoir rocks, reducing natural productivity. It results from a combination of factors such as pore size distribution, fines migration, fluid compatibility, wettability, and deposition of organic and inorganic substances • Use of calcium carbonate bridging agents recommended. • Use of laminar flow in horizontal holes reduces filtrate loss to the reservoir and helps to stabilize unconsolidated formations. • High viscosity reduces losses in fractured formations. • Unique bridging mechanism gives external filter cake. • DrillSmooth additive complexes bentonite to prevent invasion. • Clean, low-viscosity filtrate with low spurt loss. • Clay stabilization from DrillSmooth additive. • Filter cake easily removed, with low cake lift-off pressure.
Formation Damage Characteristics Good rheology -good bridging Poor rheology - invasion
Return Permeability Tests: Field Cores W. Africa dolomite = 0.1 to 0.2 md 9-lbm/gal muds used. Return permeability was to air. Algerian sandstone = 100 to 150 md 13.4-lbm/gal muds. Return permeability was to kerosene. 125 DrillSmooth system Polymer-based mud Oil-based mud 100 75 Return permeability (%) 50 25 0 West Africa Algeria
Choice of Weighting Agent DrillSmooth fluids A Weighted to 10.5 lbm/gal with ID-CARB weighting agent. B Mud A weighted further to 13.0 lbm/gal with barite. C 15.0-lbm/gal mud weighted only with barite. Solids content as % v/v same as Mud B. 100 80 60 Return permeability (%) 40 20 0 Mud A 10.5-lbm/gal ID-CARB Mud B 10.0-lbm/gal ID-CARB/barite Mud C 15.0-lbm/gal barite only
Stabilization with ID-PTS Temperature Stabilizer 4 lbm/bbl ID-MMO FL additive 6 lbm/bbl ID-MMO FL additive 45 12 40 275°F [135°C] 35 10 30 300°F [149°C] 8 25 API fluid loss (mL) 20 API fluid loss (mL) 6 15 10 4 5 2 0 –2 0 2 4 6 0 4 6 6 8 ID-PTS additive (lbm/bbl) ID-PTS additive (lbm/bbl) Results after hot rolling 16 hr at 300°F [149°C] Results in 17.0-lbm/gal [2.04 sg] fluid afterhot rolling for 16 hr at temperature shown
What Does DrillSmoothOffer? Instantaneous and very effective suspension Excellent hole cleaning Resistance to movement along fractures Totally external filter cake if properly treated Minimal washout due to dead zone at wellbore Environmental peace of mind Temperature stability
Applications • High-angle and horizontal wells • Stabilization of poorly consolidated or sloughing formations • Control seepage losses, and lost circulation in fractured zones • Wells with sensitive reservoirs or open-hole completions • Casing milling operations • Large diameter hole * Mark of Schlumberger
High Angle and Horizontal Wells • WellboreStability • Shale inhibition and mud weight • Hole Cleaning/prevention of formation of cuttings beds • Mud rheology and flowrate • Fluid Loss Control • Prevent differential sticking • Lubricity • Minimize torque and drag • Minimal Production Impairment • Non-damaging fluid with easy clean up and good return permeabilities
Wellbore Stability • Mud chemistry is dealt with using normal principals • Density control is critical • Safe mud weight depends on stresses • Increase in MW approx. 0.1SG (0.83 ppg) / 30 ° Fracture Initiation Stable Collapse * Mark of Schlumberger
Cuttings Transport Flow Regime versus Annulus Inclination or Hole Angle Laminar Flow No Cuttings Bed build up "Normal" Hydraulics Turbulent Flow Cuttings Bed formation 0° to 25° Tendency to slip 25° to 65° Cuttings Bed 65° to 90° No slippage In many deviated holes, high torque and drag arise from the presence of cuttings beds rather than from any inherant deficiency in lubricity.
Field Observations and Achievements • Cake easily cleaned up. • No problem with plugged sand screens or liners. • Record casing milling runs • Hole angles from 0° to 105°. • Mud weights from 8.0 to 15.0 lbm/gal [0.96 to 1.80 sg]. • BHST to 320°F [160°C]. • Reduction of losses in fractured formations. • Low torque and drag. • Gauge hole through a variety of lithologies. • No settling on trips. Zero lag time. • Cuttings show no signs of disintegration. • Excellent well productivity in sandstone and carbonate reservoirs.
Kurdistan Case History-1: Gulf Keystone well (2014-15) • Witnessing very significant success of DRILSMOOTH (MMO) system in drilling 26’’ and 17 ½’’ sections of the well, 12 ¼” hole was also drilled through, Sarmond, Garagu, Chia Gara and Barsarin up to the 9 5/8” casing point 1965m / 1610m TVD with 56º inclination. • There was significant control of formation losses (as depicted in following slides) and absolutely no hole cleaning issues. • Several runs of well Logging over a long time, enhanced the well exposure time and the casing running faced obstructions in Garagu shales which needed higher inhibition levels. • In MMO system the inhibition level could be attained with 2-3% KCl (< 20,000 chloride limit to use it) and with up to 3% ID-FURY. • Seeing the inhibition limitations of the MMO system, the whole system was easily broken down to KCl-Polymer system and re-conditioned the well for successful running of the casing.
Kurdistan Case History-1: Gulf Keystone Well (2014-15) • Advantages recorded using MMO mud in SH-11 vis-à-vis SH-10 drilled from the same pad • Overall losses were 33% less using MMO mud in 26’’, 17 ½’’, and 12 ¼’’ holes. • Total well mud cost was 18% less vis-à-vis the previous well drilled. • For SH-11, planned well depth was 2157 with 43.41º inclination, actual was 2348m with 62.9º, an 8 % longer well bore with higher inclination. • Planned drilling-cum-completion days were 75 whereas the well was completed in 65 days, saving 13% rig time and money. • Incurred 18% less mud and Engineering cost.
Kurdistan Case history-1: Gulf Keystone Well (2014-15) Pictorial presentation of the comparison of three wells drilled by the same client in the same block:
Kurdistan Case History-2: TOTAL E&P well (2014-15) TOTAL planned to use the MMO system for first two intervals (26” and 17 ½”) only, then due to its excellent performance and trouble-free operations, decided to use it on the 12 ¼” and 8 ½” hole sections as well. The 7” liner was just set and drilling resumed with KCl/Polymer mud just for one reason, to reduce the ECD due to low fracture gradient. Inhibition to the MMO system was provided by using 0.5% v/v AS-Y and 2% v/v ID-FURY. Lubricity provided by using Graphite powder, ID-FURY and ID-LUBE XL.
Kurdistan Case History-2: TOTAL E&P well (2014-15) The drilling curve is ahead of planned, and if not for the many rig equipment failures and geological side-track, more time could have been saved: Geological side-track
Background Challenge: To improve MMO system’s inhibition and expand its applications Solution: QMax received cuttings from different troublesome formations in North Iraq region and sent to our R&D Center in Houston for testing Several tests were done comparing different inhibitors and their impact on system’s rheology and inhibition performance Lab test matrix was set for the project
Gasplus Cuttings SH-2A well in Kolosh SHEWSHAW-2A well in Tanjero
Linear Swelling: Gasplus Cuttings SH-2A well in Kolosh SHEWSHAW-2A well in Tanjero
Clay Recovery Test MMO-based Silicate-based
MMO Inhibition Improvement – Further Studies Due to the continued success of the DrilSmooth system in other areas, further tests were performed in Houston to boost system’s inhibition using a combination of regular and new inhibitors Cuttings samples from East Africa were sent to the lab in Houston to check on the best combination of inhibitors to use in the field and stabilize these formations
