Drilling mud Equipment

Desilter is the third phrase solids control equipment. It is usually used following shale shaker, desander.

Desilter is usually combined of a under fluid shale shaker and desilter hydrocyclone assy.

Under fluid shale shaker:

For a better separation result, many users will choose a under fluid shale shaker under desilter hydrocyclone assembly.

Solids phase discharged from desilter cyclone can be further separated by shale shaker. Useful mud falls into tank for recycling.

Hydrocyclone Assy:

4’’ hydrocyclone is most widely used for desilter in oil & gas drilling field. And quantity can customized per clients requirements, vary from 4 each to 24 each.

Advantages of GN brand desilter

As world top solids control manufacturer, GN Solids Control have following strong points compare with othes:

1) Big underflow shale shaker: GNZS752 for better separation and compact design with small footprint of non-underfluid model

2) 100% Polyurethane (PU) ,material for desilter cnoes with longer using lift, and interchangeable with Derrick.

3) Shut off stainless steel ball valve available for option on each cone inlet permit individual cone removal and inspection without interrupting operation of the desilter

4) Tangentially blended into the cone entry as a narrow rectangle to minimize turbulence in the upper section of the cone, allowing the solids to move quickly to the cone wall.

5) Flexable fast connection are available for user friendly assy.

The shale shaker is the most important solids control equipments, it’s the first phase of the solids control for drilling mud.The following tips will help you to achieve the
Use finest shale shaker screens possible
Unless specific drilling fluid requirements dictate otherwise, always use the finest screens possible without incurring mud carryover and with the shaker being configured in optimum set-up condition i.e. angle, pool depth etc.

Replace Damaged Shaker Screens
Never allow torn screens to be used. As holes appear change and repair out at the first opportunity.

Proper Cleaning of the Shaker
Never clean shaker screens with brushes or sticks. The poor transportation requiring the use of brushes should be addressed at source. Always use appropriate cleaning solution. Never use water with an oil or synthetic based mud.

Screen Storage.
Shale shakers are the first and main defence against solids. The screens are fundamental in the operation. Do not store, transport or handle them inappropriately.

Correct supervision
Screens can significantly improve solids control efficiency.

Never By Pass
Never by-pass the shaker except in an Emergency.

Maintenance of the Shaker
Ensure the shaker components are in good order; rubber supports, tensioning mounts etc.

For proper mixing and suspension of solids, the mud agitator must be properly sized and installed.

To properly size a mud agitator, proceed as follows:
1. Select desired style – horizontal with welded or casting impeller
2. Determine available electric power – 440V/460V/380，60HZ , 380V/400V/415V，50HZ or customized.
3. Select horsepower and impeller(s) as determined by the following factors:
a. Tank design – round or square
b. Tank dimensions
c. Maximum mud weight
d. Desired turnover ratio (TOR)

After gathering the required information, the agitator can be properly sized to meet the horsepower demand and correct agitation for the application. GN Solids Control as world top 4 solids control and waste management supplier,can offer  customized agitator size to meet different tank situation.

To ensure accurate sizing, GN recommends clients to communicate with GN people to make sure size and model.

Following are operational recommendations for mud agitators:
1. Maintain uniform tank dimensions, i.e. equal width-to-length ratio or as close as possible to equal.
2. Avoid TOR values greater than 85 seconds, as this may jeopardize solids suspension.
3. Avoid TOR values less than 40 seconds, as this may result in formation of a vortex and increase air entrapment.

Solids control system is very popular used in the oil and gas drilling, HDD and CBM drilling. For oil and gas drilling, in the past, the driller would dig a large pit on the groud to reserve the used drilling fluids. After the drilling cutting sedimented to the bottom of the mud pit, the upper lever drilling fluids would be reused. To some extent, this method could save some drilling fluids, but the enviromental harmful mud pit brought problems for the driller.

With the fast developing of the drilling industry, the traditional mud pit for solids control would not meet the driller’s request for quickly drilling, as the traditional mud pit solids control would cost much time to sediment the drilling cuttings. If the driller start a new drill, then they need new drilling fluids.

In order to enhance the efficience of solids control, reduce the cost for drilling fluids and harm to environment. The technology of pitless was brought into solids control. Pitless solids control system often used in closed loop drilling system. Including the shale shaker, mud cleaner and centrifuge based on the mud tank, the pitless solids control system could circulate the drilling fluids out of the borehole without reserving in the digged sump. The mud tank functioned as the mud pit, after treatment by the solids control equipments, the drilling fluids could be reused without waiting for cuttings sedimentation.

The cuttings discharged from the solids control system and waste management equipments like Verti G cutting drier would be moved to the cuttings drying and holding area bottom built with an impermeable clay bed covered with caliche. After complete drying, the cuttings could be transported for further disposal.

GN Solids Control, the first API certified manufacturer for drilling mud solids control and waste management equipments, could offer the complete pitless solids control system for drilling projects, for more information,please contact with GN Solids Control.

With the reason of decreasing overall environmental impact, and reducing total cost for drilling operation.Fluids recovery technology is growing fast and wide. One of the major concerns about fluid loss recovery technology is ultrafines. Vacuum screen drilling recovery system does not create fines, which solve this problem.

Vacuum shaker screen can fit all types of shakers. It sucks the drilling mud out of the cuttings as it passes over the last screen on the shaker.

Vacuum shaker screen recovery system is attaching a vacuum manifold under the shaker screen or installing a vacuum manifold that has a shaker screen attached to it. The system is attached to the shaker’s vibrating basket so the manifold vibrates with the shaker as it is running. Attached to the manifold is a vacuum line with a fluid/air separator; this is connected to the vacuum collection tank. The vacuum unit is installed as close as possible to the shaker to keep the distance that the recovered fluid is transported as short as possible.

Advantages of vacuum shaker screen system:

1. Increased emulsion stability in recovered fluid
2. Higher density in recovered fluid
3. Lower viscosity in recovered fluid
4. No detrimental effects on main drilling fluid system rheology
5. Decrease in low gravity solids to high gravity solids ratio
6. Dehumidify fluid
7. No evident increase in concentration of ultrafine solids
8. Elimination of sawdust/rubber crumb usage for mixing off shaker cuttings
9. Initial review saw a decrease in waste haulage by 20%
10. Elimination or severe reduction in oil spray gun usage to clean shakers.
11. Reduced centrifuging required
12. Improved shaker operations, allowing for finer screens to be run
13. Increased shaker screen life

Shaker screen is the most important parts for shale shaker. Suitable screen size and reliable screen quality can greatly reduce drilling cost. And good design shale shaker can prolong lifetime of shaker screen.

Screen size usually indicated by mesh size or API size. Many clients wonder: what is difference of mesh size and API size? can they convert to each other?

Definition of mesh size:

Mesh count is the number of opening per inch in directions perpendicular to each other and parallel to the screen wires. For example, a 40-mesh screen would have 40 openings per inch in one direction and 40 openings per inch in a perpendicular direction. In an effort to eliminate calling the screen a “40 by 40” screen, the common terminology resulted in calling the screen a 40-mesh.

During the 1960’s, the throughput volume was increase by making rectangular openings. If the mesh count was 20 opeings in one direction and 40 openings in a perpendicular direction, the screen would be labeled a 20×40 mesh. The marketing ploy, however, was to label the screen with a letter and then the number 60. This implied to many that the screen was a 60-mesh screen.

Although this was not stated explicitly. Rig crews were happy because the “fine-mesh” screens could handle more flow than a normal square-mesh screen. After rectangular screens became common, shale shaker throughtput was increased again. by mounting one screen on top of another screen instead of using only a single layer, see figure.

This layering created even more of a description problem because the opening were now non-uniform and difficult to describe. In the sketch, one square mesh screen is shown superimposed over another square mesh screen. A variety of opening resulted that cannot be described by a single number.

API size

In an effort to better describe multilayered shaker screens, API issued API RP13.

API is used to identify the largest solid that would pass through each screen (or the smallest solid captured by the screen); this is called D100. Solids smaller than D100 will pass though a D100 screen. Each screen manufacturer have its own D100 count (screen openings microns), but the micro court should among the same scope related a a certain API count. For example: D100: 137.5 ~165.0 equaled to API 100.

See below charge:

 

Extractor,  most commonly called vertical cutting dryer,it is the main equipment for drilling waste management. GN Extractor utilizes centrifugal force to dry drilled solids in oil or synthetic based fluids.

In extractor (cutting dryer), a stainless steel screen bowl traps “wet” solids and accelerates them up 900RPM with G force up to 420. Liquid is forced through the screen bowl openings, while “dry” solids are extracted by the angled flights attached to the cone, which rotate slightly slower than the bowl. Tungsten carbide protects the flights from abrasive solids and ensures long operational life. This aids in maintaining a constant gap between the scroll and screen bowl, which is crucial for proper operation.

GN extractor (cutting dryer) has been done strict balance testing for all major rotary components to minimize vibration & noisy.It is the ideal products for oil based drilling waste management.

How waste management system processing (oil based mud):

1) cuttings from shale shaker, desander,desilter comes into verticalcutting dryer through screw conveyor (auger)

2) After treatment of extractor:

a. useful mud back to recycling system for dilling.

b. waste solids discharged

c. recycled drilling fluids comes into GN Decanter Centrifuge for recovering.

What mud cleaner is:

Mud cleaner, also called mud conditioner, were developed in the early 1970s to remove fine drilled solids from weighted mud without excessive loss of barite and fluid. It is also proved valuable tools in closed systems and other applications. Mud cleaner use a combination of desander and/or desilter hydrocyclones and very fine mesh vibrating screens (120-400 mesh) to remove fine drilled solids while returning valuable mud additives and liquids back to the active mud system.

 Hydrocyclone sizes of mud cleaner

are designed arbitrarily by the inside cone diameter at the inlet. By convention, desanders have a cone diameter of 6 inches and larger; desilters have internal diameters smaller than 6 inches.

Normally, discharges from the apex of mud cleaner cones are discarded when used on unweighted drilling fluids. Prolonged use of these cones on a weighted drilling fluid will result in a significant reduction in drillingfluid density caused by the discard of weighting material. When these cones are used as part of a mud cleaner configuration, the cone underflow is presented to a shaker screen. The shaker screen returns most of the barite and liquid to the drilling-fluid system, rejecting solids larger than the screen mesh. This is a common application of unbalanced hydrocyclones, since the cut point is determined by the shaker screen and not the cone.

GN ZJ series mud cleaner

chooses 10’’ desanser cone and 4’’ desilter cone as standard configuration. According to capacity requirements, mud condition and underflow shaker model, 10’’ desander cone option from 1~3, and desilter cone option from 8~16.

Here is an usual combination of desander cone and desilter cone :

1×10’’ cone with 8×4’’ cone;

2×10’’ cone with 12×4’’ cone;

3×10’’ cone with 16×4’’ cone;

Acrroding to detailed insite situation, desander / desilter cone number and be increased or reduced to enable a better performance.

World top 5 mud cleaner brand:

Top 1: Derrick

Top 2: Brandt

Top 3: Swaco

Top 4: GN Solids Control

Top 5: Kem-tron

Big capacity mud tanks on promotion now. The tanks from world top solids control and drilling waste management manufacturer- GN Solids Control.

Specifications of the tanks:

1) 7x400BBL Mud Tankfor one set

2) 3 sets total capacity=8400BBL

3) Dimension (LxWxH):1200x2900x2300mm

4) Including Shaker Tank, suction tank, storage tanks, mixing tanks completed with agitators, mud guns, and centrifugal pumps.

Option items: Shale Screens

With Coverage roof for Sun and Rain protection.

This is optional for buyers.

Equipments can mounted on the tank:

1) 3x Linear Motion Shale Shaker : Derrick FLC2000 or GNZS703Model

2) 1xVacuum Degasser: Derrick 1200 or GNCQ270

3) 1xMud Cleaner with 3x10inch desander and 16x4inch desilter, underflow linear motion shaker:Derrick FLC2000 or GNZJ703-3S16N

4) 2xDecanter Centrifuge: Derrick DE1000 Or GNLW363

The configuration for above is flexible,you can choose not ot have centrifuge or degasser or less shakers etc.

The tanks can be used for 1000hp or 1500hp drilling rig mud system. Some clients buy them as storage tank or water tank as the good price. Both good choice.

GN Solids Control offer mud agitator various from 5.5kw to 15 kw.

How to choose the right agitator model for your tank?

It depends on following:

1) tank/tank compartment inner dimention,usually, every 3 meters in tank length, there should be an agitator

2) identify voltage & hz of explosion proof motor

3) density & viscosity of fluids

Agitator Shaft

According to tank inner depth.

Shaft Stabilizer for agitator

While tank depth over 8′ , stablizer for agitator shaft  is necessary, to fix shaft in tank.

Shaft stabilizer welded on tank bottom.

Impeller

Impeller diameter various from 20’’ to  52’’,depends on tank dimension.

As suggested by GN Solids Control, for motors below 11kw (5.5kw. 7.5kw), single shaft is ok.

For motors over 11kw (11kw,15kw) single impeller and double impeller both acceptable.

While impeller more then 1 layer, the up impeller mounted near to mud surface, the down impeller mounted to 0.75 times of impeller diameter. Namely, for 20’’ impeller, it should mounted 15’’ above tank bottom.