9 - Solid Control PTM_Handout

5/21/2010

Global Research & Technology Centre/ GRTC Training Department

Solids Control Equipment

SCOMI OILTOOLS

Drilling

and Making Hole

Drilling out hole with bit and generate cuttings The mud brings the cutting up to surface At surface, cutting will be separated out from mud. Cutting will be discarded

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Drilling

and Making Hole

SOLID CONTROL

CUTTINGS discarded WASTE

MUD

At surface, cutting will be separated out from mud. Cutting will be discarded

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What is mud

LIQUID WATER OIL

SOLIDS

MUD

BENTONITE/GEL

WATER-BASE MUD

BARITE CHEMICALS SALT

OIL-BASE MUD

DRILL SOLIDS SCOMI OILTOOLS

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Where do they put the Solid Control Equipments on a Rig ?

ON TOP OF THE MUD TANKS Just before the mud coming out from down hole returns to the mud tanks

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Relation of Particle Size to Solids Removal Equipments

DESILTER

DESANDER

SHALE SHAKER

CENTRIFUGE

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PRINCIPLES of SOLIDS CONTROL EQUIPMENT (SCE)

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Particle Size Classification API Classification

Size Range (microns)

Common Term

Coarse Intermediate Medium Fine Ultra Fine Colloidal

> 2000 250 - 2000 74 - 250 44 - 74 2 - 44 0-2

Sand Sand Fine Sand Silt Clay Clay

Common ArticleSize

Range (microns)

Beach Sand Human Hair Fly Ash Cement dust Pollen Red Blood Cell Paint Pigment

80 - 2000 30 - 200 1 - 200 3 - 100 10 - 100 7.2 - 7.8 1.0 - 5

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Solids Control

You can stop this happening SCOMI OILTOOLS

TYPE OF SCE 1. Gravity or Settling In the past, large earthen pits are used as settling traps and the pit becomes the solids control equipment. These methods are becoming obsolete for the oil & gas drilling industry and are definitely not cost effective. Today, sand trap pits are common used offshore. The appropriate size for a sand trap pit is 75 barrels. Too small a sand trap pit may not allow proper settling and too large a pit will not be cost effective. SCOMI OILTOOLS

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TYPE OF SCE 2. Dilution A common method of trying to offset the build-up of drilled solids is the addition of more liquid to the system. This is dilution and does not remove cuttings but instead reduces (or dilutes) their concentration in a drilling mud, thereby reducing the presence of total solids in the mud. It is important to note that dilution is expensive. Dilution, for every 1bbl of solids introduced to the mud, 20 bbls of fresh fluid is required to return the drilling fluid to © the correct concentration (At 5% Solids) SCOMI OILTOOLS

TYPE OF SCE 3. Solids Removal Equipment Solids removal by mechanical separation can achieve the benefits of low solids content and at the same time significantly reduce the many costs associated with dilution. The primary types of solids removal equipment include: • • • •

Shale Shaker De-sanders, De-silters (Hydro-cyclones) Mud Cleaners Centrifuges.

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Drilled Solids Separation Process • Removing large to small particles size in a closed-loop system Depending on type of equipment i.e.
Scalper or Primer

>1000 microns


Fine screen Shaker

76 microns


10”– 14” Hydro-cyclone

40 – 60 microns


4” Hydro-cyclone

20 microns


Centrifuge

2 microns

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SHALE SHAKERS

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SHALE SHAKERS

If shakers are not used effectively - other SCE downstream will not perform properly

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SHALE SHAKERS


The first and most effective (in volume terms) of removing solids.




Usually 60 -80% efficient at removing the solids that have been drilled.




All shale shakers rely on screening of the drilling fluid through a vibratory surface. The number and motion of the vibratory surface varies from one manufacturer to another.

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SHALE SHAKERS



To handle 100% of the circulation rate. The shale shaker development may be defined by the types of motion produced by the machines: •

Elliptical, “unbalanced” design

•

Circular, “balanced” design

•

Linear, “straight-line” design.

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Vibratory Motion • Conveys solids to the solids discharge end. • Allows liquid to pass through the screen. • Create a limited amount of G-forces. Linear There are three types of motions being used:

Elliptical

Circular

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SHALE SHAKERS Design performance of shakers are defined by: • Type of Motion • Stroke length • Rpm of vibrator

Vibration motion along the deck depends on: • Position of the vibrator/motor • Direction of rotation SCOMI OILTOOLS

Shale Shakers Motions – Elliptical If a vibrator is mounted above the deck the motion is: ● elliptical at the ends of the deck ● circular below the vibrator. The rate of travel of the solids is controlled by: ● ● ●

the axis of the ellipse, slope of the screens, and direction of rotation.

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Shale Shakers Motions – Elliptical • The elliptical shaker requires a downward slope basket to properly transport cuttings across the screen and off the discharge end. • This reduces fluid retention time and limits the capacity of this design. • Optimum screening with these types of shakers is usually in the 30-40 mesh (400-600 micron) range.

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Shale Shakers Motions – Circular The circular motion shaker was introduced in the late 1960s and early 1970s. •

•

•

If the vibrator is mounted close to the screens and center of gravity, the motion is circular. Cuttings travel direction and speed on a horizontal deck depends on the • direction of rotation, • the frequency of vibration • the amplitude of motion.

Amplitude of motion is the distance from the mean position of the motion to the point of maximum displacement. For a circular motion, the amplitude is the radius of a point on the screen deck side. The stroke is the total movement or twice the amplitude

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Shale Shakers Motions – Circular • The consistent, circular vibration allows adequate solids transport with the basket in a flat, horizontal orientation. • This design often incorporates multiple decks to split the solids load. • Allows finer mesh screens, such as 80-100 mesh (150-180 micron) screens.

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Shale Shakers Motions – Linear

Linear

● The linear, or straight-line, motion shaker was introduced in the late 1970s. ● This motion is developed by a pair of eccentric shafts rotating in opposite directions. ● Linear motion provides superior cuttings conveyance and being able to operate at an uphill slope provides improved liquid retention. Better conveyance and longer fluid retention allow the use of 200 mesh (74 micron) screens.

● The rate of travel of cuttings depends on the slope of the motion axis, the slope of the screens, the length of stroke, and the vibration frequency. Linear motion machines can be run uphill, which allows greater deck coverage by the fluid and provides a higher solids load capacity. SCOMI OILTOOLS

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Shale Shakers Motions – Linear

Linear

• The stroke length for a given design depends on the eccentric weights employed and rpm of the vibrator. The greater the eccentricity of the weights and higher the rpm, the greater the thrust. • There are practical limits in any design as to the horsepower a shaker can utilize. SCOMI OILTOOLS

G force • Sample Shaker G Factor measurement Aid • Periodic check of the shaker g force will give immediate indications of mechanical problems with the shakers. Stroke (inches) x RPM2 “g” factor = 70490

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Shale Shakers – Screening Comparison The higher the ‘‘g’’ factor • The greater the solids separation possible. • The higher the solids capacity - the less tendency there is for the screens to blind. Blinding : Reduction of open area in a screening surface caused by • Plugging OR Coating. Screens are plugged - when solids are wedged or jammed in the screen opening Coating is - reduction in the size opening of screen due to a buildup of a film in the wires such as salt, polymer, etc. SCOMIgypsum, OILTOOLS

Shale Shakers – Screening Comparison • A “g” factor that is too high for a shaker’s screen supports may reduce the life of a screen. • Proper screen tension is critical to assure good screen life. Shale shakers have capacity limits. Exceeding a capacity limit means excessive mud will be discharged over the ends along with the solids. Capacity limits can only be defined when the screens are not blinded.

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Shale Shakers – Screening Comparison • There are two capacity limits on a shale shaker: 1. The solids capacity limit is the maximum amount of solids that a device will convey. 2. The liquid limit is the maximum gpm capacity for various drilling muds. • Usually the solids capacity limit is encountered only when drilling soft, gummy formations or drilling large diameter holes with high penetration rates. • The overall capacity of the shaker is a combination of the solids capacity limit and the SCOMI OILTOOLS liquid capacity limit.

Gumbo Problem • Gumbo solids are young, unconsolidated clays that tend to be sticky and easily dispersed. • They hydrate and disperse on the way up the hole. • What is not removed at surface is entrained in the mud system as colloidal sized particles (>2 microns). • Problems include: • The more energy put into gumbo solid, the more “plastic” the solid becomes. • Blinding of shaker screens. • Increased mud dilution and chemical additions. SCOMI OILTOOLS

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Gumbo Traps/Screens Three main methods exist for removal: • Bars/Trap: the earliest gumbo removal systems where made up of a series of inclined bars used to deflect the gumbo overboard. • Chains : Gumbo chains drive the gumbo along an inclined bed and discharges it. • Conveying Method : as used in the Derrick Flo-Primer. This conveyor belt carries the gumbo away efficiently and allows the fluid to pass through the urethane mesh (Mesh sizes 5, 10, 20 & 30 are available)

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SHALE SHAKERS

Flo-Line® Cleaner 500

Flo-Line® Cleaner 2000

Fluid Cleaner 313M

Dual Pool 600 Series

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Dual Pool Concept • Innovative Next Generation Design Providing • Increased capacity in same overall foot print • Maximized available screening area • “Fluid centering technology”  Maximizing fluid throughput • Resulting In Fewer Shakers Required

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Fluid Centering Technology

FLC 513/514

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Dual Pool 618

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Optional Scalping Deck

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Flow Distribution System/ Flo-Divider Function: • To distribute the flow evenly from the well over all available Shale shakers • This is a key factor in performance of downstream equipment.

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Shale Shaker Lay-Out OK

x x BEST

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Even distribution of fluid and solids to shakers

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SHALE SHAKER SCREENS

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SHALE SHAKER SCREENS • Screens are a filtering device. • High-speed linear motion shakers have allowed screen technology to move forward. • Screens finer than 200 mesh are now common.

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SHALE SHAKER SCREENS • Histrorically, the drilling industry has ranked shale shaker screens by  mesh count  opening size  percent open area. • The field operating procedure has been to run as fine a mesh as possible on un-weighted fluids and fine as fine as possible up to 200 mesh (74 microns) on weighted.

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SHALE SHAKER SCREENS Shale Shaker Screens ● Shale shakers remove solids by processing solid-laden drilling fluid over the vibrating screens. ● Particles smaller than the screen openings pass through the screen along with the liquid. ● Larger particles are separated into the shaker overflow and disposed of. Desirable characteristics for shaker screens are: ● Large liquid flow rate capacity ● Plugging and blinding resistance ● Acceptable service life ● Easy identification. SCOMI OILTOOLS

SHALE SHAKER SCREENS Factors that determine the effectiveness of a screen are ● mesh size ● screen design. Mesh Size. ● The screen opening size determines the particle size a shaker can remove. ● Screen mesh is the number of openings per linear inch as measured from the centre of the wire. ● A mesh count of 50 x 50 indicates a square mesh having 50 openings per inch in both axis directions. ● A 60 x 40 mesh indicates a rectangular opening SCOMI OILTOOLS having 60 openings per inch in one direction and

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SHALE SHAKER SCREENS ● Liquid forms a high surface tension film on the wires reducing the effective opening. ● This film effect is increased with increasing viscosity. ● Piggy backing – small particles are attached to bigger particles. ● Smaller particles than the openings can be removed but liquid through put is reduced.

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SHALE SHAKER SCREENS Screens are available in two and three dimensional designs. ● Two-dimensional screens can be classified as: ● Panel Screens, are manufactured with two or three layers bound at each side by the hook strips. ● Perforated Plate Screens, are manufactured with two or three layers bonded to a perforated metal plate. These can be patched / repaired

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SHALE SHAKER SCREENS ● Three-dimensional screens : ● Three-dimensional screens are manufactured with a perforated base plate and covered with a corrugated screen cloth. This configuration provides more screen area than the twodimensional screen configuration.

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SCREENS DESIGN Difference between two dimensions and three

Gravity Forces Solids Into Troughs

Solids Form Continuous Bed Impeding Fluid Throughput

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Screen Conductance • Screen conductance is the permeability of the screen cloth divided by the thickness of the cloth and is given in kiloDarcy's per millimeter (KD/MM). • Screen conductance is a measure of the amount of fluid that will pass through a screen. • Screen permeability is determined by the porosity of the screen and wire surface area, which causes drag on the fluid and restricts movement of the fluid through the screen. • Conductance can be calculated from knowledge of the weave of the cloth, the mesh count, and the wile diameter.

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SHALE SHAKER SCREENS LABELING Two API Regulationfor screen comparison / evaluation API RP 13E • Solid Removal Potency-Cut Point • Open Area for liquid to flow • Conductance API RP 13C • API No • Equivalent mesh size • Conductance • Open Area

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SHALE SHAKER SCREENS LABELING

API RP 13-E

• • • • • • •

Manufacturer’s Designation D-50 Cut point in Microns D-16 Cut Point in Microns D-84 Cut Point in Microns Conductance in Kilodarcies per Millimeter Actual Screen Area Available for Screening in Sq. Ft. Tag with all information Perma nently Attached to the screen in a Visible Place.

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SHALE SHAKER SCREENS LABELING

API RP 13-E DERRICK® BUFFALO, NY U.S.A. D-5O/69 D-16/49 D-84/84 CONDUCTANCE 1.39 AREA 8.3 PATENTED - PMD 48-30 DX 250

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API RP 13C Labeling API RP 13C specifies that a permanent tag or label shall be attached to screen in a position that is both visible and legible

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SHAKER SCREENS ARRANGEMENT For double-deck shakers • Run a coarser screen on top and a finer screen on bottom. • The coarser screen should be at least two meshes coarser. • Watch for a torn bottom screen. • Replace or patch torn screens at once. • Cover 75% to 80% of the bottom screen with mud to maximize utilization of the available screen area. • It is very important that the bottom screen be checked often for tears. For example, use a combination of 100 mesh and 80 mesh NOT 100 mesh and 50 mesh SCOMI OILTOOLS

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SHAKER SCREENS ARRANGEMENT For a single—deck shaker with parallel screens • Try to run all the same mesh screens. • If coarser screens are necessary to prevent mud loss, no more than two meshes should be on the shaker at one time • Finer mesh screen closest to the weir side and coarse towards beach area. • Cover 75% to 80% of the screen area with mud to properly utilize the screen surface. • If a shaker has multiple screens in series or parallel shakers are used, separation is determined by the coarsest screen. Shakers in parallel should use the same mesh screens. SCOMI OILTOOLS

HYDRO-CYCLONES

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HYDRO CYCLONES

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HYDRO CYCLONES

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HYDRO-CYCLONE •

DE-SANDERS –

till 40 microns

•

DE-SILTERS –

till 20 microns

•

MUD CLEANERS – vibrating screen underneath to recover expensive fluid – solid removal will depend upon the screen size – with 200 mesh possible to remove 76 microns

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HYDRO-CYCLONE Hydro-cyclones • (centrifugal force separation process) • Downstream from the Shale Shaker, Hydro-cyclones (besides shakers) are the only other mud treatment tool to effectively treat 110% of the maximum circulating volume.

De-sander capacity Per 10” cone = 500 GPM Cut point = 40-60 microns

De-silter capacity Per 4” cone = 50 GPM Cut point = 20-40 microns

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Hydro-Cyclone – Operating Principles • Feed Chamber is cylindrical • Mud inlet at the top of feed chamber is tangent to the wall • Involute flow

– from circular feed inletturbulent flow for longer period – reduced separation efficiency

• Tangential flow – from rectangular feed inlet -reduces turbulence – increase separation efficiency

• Solid Discharge end is conical called underflow • Vortex Finder - Extending inwards at the top & in the center • Overflow opening – much larger than inlet & underflow SCOMI OILTOOLS

Hydro-Cyclone – Operating Principles •

Centrifugal pump provides high velocity – resulting in Centrifugal forces

•

Vortex Finder causes the stream to spiral downwards

•

Solids are thrown outwards toward the hydrocyclone wall, in the downward spiraling stream

•

The solids separation based on density & size

•

same density cuttings size matters

•

Increasing forces with narrowing of the cone results in inner layer of liquid turning back upwards

•

In balanced design cyclone – last of the liquid turns back upward, but solids due to high inertia & high downward velocity, continue out the underflow.

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Hydro-Cyclone – Spray Discharge • Solids concentration increases on cone walls • spiraling downwards • decreasing narrower

space

as

cone

gets

• If there are not too many solids (by volume) in the downward spiraling stream, the spray underflow appears. • Solids discharged are covered by a liquid film, vary from 90% (in case of very fine solids) to 50% (in case of very coarse sand) being removed • The inside stream moving upwards at high velocity carries air with it by friction, and this air moving upward is replaced by air entering the underflow opening. SCOMI OILTOOLS

Hydro-Cyclone Discharge : Normal vs Rope Underflow

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Hydro-Cyclone Discharge : Normal vs Rope Underflow

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Hydro-Cyclone Discharge: Spray Pattern

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Hydrocyclone – Field Balancing

• Fill pits with Water – start the centrifugal pump - feed Hydrocyclone • Wide Open the underflow • With under flow fully open water will spin out in a thin shell – Too Wet Discharge • Adjust the underflow slowly to smaller size till water spray becomes a drip

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Hydro-Cyclone –Dry Plugging • If clear water is not discharged – Over adjusted/too dry • Solids will have to climb over the ‘beach’ area to discharge • Coarse particles will go across the beach area • Medium & Fine (< 40 microns) will stick on the beach area and form a Dry Plug • Dry Plug is dense and becomes very hard, very difficult to remove from hydrocyclones.

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Hydro-Cyclone –Feed Plugging If Plugging is partial • Reason hard objects like piece of welding rod/cement • decrease in velocity at the inlet – loss of hydrocyclone action • it works like a swirling funnel with all the mud going out the bottom in an inverted cone shape. Even clean mud from overflow may flow backward. ● If Plugging is complete • Reason soft object like glove/rag/float collar rubber • clean mud from the overflow of other cones is lost • the mud loss rate is high SCOMI OILTOOLS • discharge is straight ●

Hydro-Cyclone – Feed Pressure The pressure required for a hydro-cyclone to work properly is 75 feet head mud wt. (ppg) X 4 = PSI at the feed inlet It will be mud weight (ppg) X 4.4 at the centrifuge

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Hydro-Cyclone – Bad Manifolding Arrangement BOTTLENECK 10” x 6” x 35 ft. length may cause back pressure, resulting in wetter undercone discharge.

BOTTLENECK 8” x 6” x 30 ft. length may cause back pressure, resulting in wetter undercone discharge.

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Hydro-Cyclone – Good Manifolding Arrangement

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Hydro-Cyclone – Benefits Benefits of having hydro-cyclones: • Allows for coarser mesh or lower deck angle to be run on fine screen shakers while balancing the load between the two. Providing longer screen life (mud cleaner mode) • Provides redundancy between shakers and centrifuges in closed or semi-closed loop systems • Operate as a solids scalper for centrifuge operation

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Mud Cleaner Mud Cleaner: Use to salvage expensive fluids back to active system

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Desander

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Desilter

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CENTRIFUGES

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Centrifuges – Principle & Theory of Operation Function A decanting centrifuge consists of a conical, horizontal steel bowl that rotates at high speed using a double screw type conveyor. The conveyor rotates in the same direction as the outer bowl but at a slightly slower speed.

Use Centrifuges are typically used to: • Remove drilled solids from the active mud system • Process recovered drilling fluid from the Extractor Dryer & Hi-G Dryer. SCOMI OILTOOLS

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Decanting Centrifuge • Downstream treatment of the hydrocyclones is the centrifuge. • Centrifuges are effective tool to removed solids particle size down to 2 micron. • A single centrifuge can handle approximately 10% to 20% of the circulation rate.

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Decanter centrifuge system design All decanter centrifuge has similar features i.e. •

Rotation assembly, bowl and scroll

•

Gearbox, for scroll drive

•

Effluent ports, for setting pond depth

•

Hard face discharge ports

•

Safety cut off switches, overload and heavy vibration

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Decanter centrifuge system design

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Bowl

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Screw Conveyor / Scroll

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Derrick DE7200

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Brandt/Varco HS-2172

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Derrick VFD-1000

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Centrifuge – Separation Guideline Low mud weight • Lower conveying torque • Higher bowl rpm High mud weight • Higher conveying torque • Lower bowl rpm • Reduce feed capacity High viscosity • Reduce feed capacity

= higher feed volume = better cut point = lower feed volume = lower cut point = increase cut point = increase cut point

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G Force G-Force = .0000142 x rpm2 x bowl diameter (in) +

Increased G- Force =

Finer cut point (remove more and smaller particles)

+

Increased G- Force =

Cleaner effluent (lower density effluent)

+

Increased G- Force =

Drier solids discharge

-

Increased G- Force =

Greater stress on moving parts

-

Increased G- Force =

Increased torque (drier discharge)

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Calculating G Force Example 1:

24” Bowl Rotating at 2000 rpm

(Based on A large bowl Centrifuge) g’s = (2000)² x (0.0000142) x (24) g’s = 1363

Example 2:

14” Bowl Rotating at 2600 rpm

(Based on a DE-1000 FHD Centrifuge) g’s = (2600)² x (0.0000142) x (14) g’s = 1343 The large bowl centrifuge has to spin 600 rpm less to obtain the same G Force. SCOMI OILTOOLS

Effect of G force on Separation

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Dual centrifuging (or Barite Recovery mode) Centrifuge # 1 800-1,100 rpm

Sol. Disc.

Centrifuge # 2 < 3,000 rpm

Centrate return to #2 pump

Barite return to active

Sol. Disc.

Fine LGS solids overboard

Suction from desilter overflow 12 ppg OBM

Pump # 1

Clean mud return to active 9.5 - 10 ppg OBM

> 8 ppg OBM

Pump # 2

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Centrifuge – Barite Recovery Benefits of barite recovery system ● Recovers optimum particle size (8 - 74 microns) barite. • Makes the solids less abrasive ● Able to remove very fine solids, thus reducing mud dilution ● Improves mud property ● Reduce barite usage

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Micron 74 50 40 HGS 30 Centrifuge Removal 20 LGS 800 – 1000 rpm

10

2000 rpm 3000 rpm

2 0

10

20

30

40

50

60

70

80

90

100

%

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Centrifuges - Differential Conveyor speed • Differential RPM is the difference between the bowl RPM and the conveyor RPM. The differential is provided by the gearbox which transmits power from the bowl to the conveyor. • It determines the velocity at which solids are conveyed through a centrifuge. • Typical gear boxes are 80:1, 125:1, 40:1 and 52:1. Example • A 125:1 gearbox means that for every 125 revolutions of the bowl, the conveyor turns one (1) less or 124. • With this ratio a centrifuge rotating at 1800 RPM the conveyor has a differential speed of: 1800 / 125 = 14.4 RPM SCOMI OILTOOLS

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Centrifuges - Operating Guidelines, Centrifuging Un-weighted Mud •

For the best separation the bowl should be run at maximum RPM.

•

Operate the centrifuge just below the flood-out point.

•

When processing the active system, the centrifuge feed should be taken from the desilter discharge compartment. The centrate should be returned to the next compartment downstream.

•

The best feed rate and pond depth will depend on the size distribution of the drilled solids.

•

Use a deeper pond and lower feed rates are more efficient when removing fine drilled solids.

•

Field experimentation is necessary to optimize centrifuge set-up.

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DRILLING WASTE MANAGEMENT SCOMI OILTOOLS

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Cutting Dryer

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The Extractor Cuttings Dryer ● As increasingly strict limitations are placed on the discharge of drilling fluids and their associated drilled cuttings to the environment; the industry has adapted specialized technology to comply with these increasingly stringent discharge requirements. ● To meet the challenge of low oil on cuttings (OOC), SCOMI Oiltools has developed the Extractor horizontal dryer which can reduce Oil On Cuttings (OOC) to below 4% ● Normal operating RPM 800

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Typical Extractor Installation SCOMI OILTOOLS

Typical Extractor Installation SCOMI OILTOOLS

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Cutting Dryer Cuttings Dryer The industry has recently adapted specialized system technology to comply with the strict limitations (EPA compliant) being placed on the discharge of synthetic base fluids and their associated drilled cuttings.

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Cutting Dryers - Extractor ● The Dryer consists of a horizontally configured conical screen placed within a balanced cage that is driven at high speed via an electric motor through a Cyclo-Gear drive gearbox. ● Positioned within the cage is a scroll (Similar principles as the DE-1000 Centrifuge) that turns and transports the filtered solids from the machine to obtain maximum cuttings dryness. ● The unit is attached to an isolated sub-frame which in turn is mounted on a rugged Oilfield skid for transport

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Cutting Dryers - Extractor

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Cutting Dryer - Flow Diagram Wet drill cuttings enter into the top of the dryer Dry drill cuttings exit out the bottom of the dryer Recycled drilling fluid is recovered out the side ports

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The Screen Basket and Screen

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The Screen Basket and Screen

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Feed System The dryer receives wet cuttings from the rig solids control equipment via an application specific combination of: ● ● ● ●

Screw conveyor(s) Positive displacement cuttings pump Vacuum collection system. Gravity

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High Volume Cuttings Pump

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Typical System Lay Out

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Typical System Lay Out

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DRILLING WASTE MANAGEMENT

Before and After

‘BEFORE’

‘AFTER’

Cutting from shaker

Oil content is less than 4%

SCOMI OILTOOLS

Cutting dryer – Derrick Hi G Dryer Features ● Four panel version of the Super G Flo-Line Cleaner 2000. ● Reduces fluid loss from cuttings. ● Used to meet environmental targets for oil and drilling fluid discharge. Benefits ● Reduced drilling fluid costs. ● Elimination of whole mud losses from shakers. ● Allows finer screen capability on shakers

SCOMI OILTOOLS

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SYSTEM LAYOUT

SCOMI OILTOOLS

Solids Control Equipments on the Rig

FROM WELLBORE MUD TREATMENT (ADD CHEMICALS) DESILTER

CENTRIFUGE

DESANDER SHALE SHAKER

MIXING HOPER

OVERFLOW

TANK # 6 SUCTION TANK

TANK # 5 CENTRIFUGE TANK

UNDERFLOW

TANK # 4 DESILTER TANK UNDERFLOW

UNDERFLOW

TANK # 3 DESANDER TANK

TANK # 2 SETTLING TANK

TANK # 1 SAND TRAP TANK

UNDERFLOW

IN TO WELLBORE

MUD PUMP SCOMI OILTOOLS

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System Layouts

Flo’ Divider/ Header box

Generic Solids Control System

Shale Shakers


Active Mud Tanks

Sandtrap Degasse r

Desande r

Desilter/ Mudcleaner

Centrifuge / Centrifuge System


Tank







Waste Agitator

Equaliser




Overflow

SCOMI OILTOOLS

Basic System Un-weighted Mud

SCOMI OILTOOLS

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5/21/2010

Un-weighted Mud with Degasser

SCOMI OILTOOLS

Un-weighted Mud with Centrifuge

SCOMI OILTOOLS

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5/21/2010

Weighted Mud with Mud Cleaner & Centrifuge

SCOMI OILTOOLS

Weighted Mud centrifuging underflow from Hydrocyclones

SCOMI OILTOOLS

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