drilling mud centrifuge

GN Solids Control waste management decanter centrifuge is specially designed for drilling cuttings and various waste material. It is widely used after high G drying shaker, Vertical cuttings dryer for drilling cuttings treatment. Or used together with chemical dosing system for dewatering treatment.
Compare with normal decanter centrifuge in China or from U.S, Europe, GN Solids Control decanter centrifuges have below advantages.

GN decanter centrifuge is made per international high standard specially designed for drill cuttings and waste management. Below are some necessary features. It is much more durable than economic standard. :

GN decanter centrifuge Bowl material is Duplex Stainless Steel 2304 and by centrifugal casting; While other Chinese brand or even U.S brand are normal SS304 or SS316 made by casting. GN material grade and processing technology are both better. It ensures a better dynamic balancing during high speed operation. So GN waste decanter centrifuge has less vibration compared with other brand centrifuges at the same working situation.

GN decanter centrifuge Screw Protection is Tungsten Carbide Tiles. It can last for longer life and is easier for replacement;

GN decanter centrifuge Solids Discharge is 360° type with wear protection with 6 fully covered tungsten carbide discharge wear liners. And it is interchangeable.

GN decanter centrifuge Liquid Discharge port is protected by adjustable Weir Plates. Operators can adjust the wetness per material situation.

All Bearings used in GN decanter centrifuges are from international top brand: Original SKF or FAG.

GN Solids Control special designed mobile skid is heavy duty telescopic skid with operation height 2800m, or 4100 per clients request. Both the feeding screw pump and VFD control panel can be mounted on the skid for easy movement. There are foldable walkways and guardrails make the skid easy for movement and easy for job site layout. And it is safe and convenience for operator to go up and down to check and centrifuge operation. Clients likes GN design much.

GN Solids Control made a small liquid and solids separation system. The small system is customized for an Europe company per clients request. The client asked for a small recycling unit with cleaning capacity of about 12-15 m³ / hour. The client wants a small single centrifuge in the small recycling system.

GN Solids Control customized a compact system which is composed of a small size shale shaker and a mini size decanter centrifuge. The shale shaker and decanter centrifuge are located on a mud tank together with a centrifuge feeding pump and electric control cabinet for the whole system. Tank size for the whole system is 3900Lx2250Wx1300H (mm) for easy movement. It is a small capacity recycling system with turn-key solution. All connections inside the system are included.

The Shale shaker separator model is GNZS752F-MDZF. It is a 2-panel small size shale shaker with small footprint.

The Decanter centrifuge model is GNLW223D-VFD. It is a 9” baby centrifuge for fine solids separation. The Cut point of GNLW223D-VFD centrifuge is 2 ~ 5 microns.

The color, brand and logo are all customized per client’s request. GN Solids Control is capable to make other customized system per clients job site situation. Clients can contact GN Solids Control sales engineer to get customized solutions.

Besides the small mud recycling system, GN Solids Control makes various sizes of Mud Recycling System for HDD, water well drilling, Trenchless, Piling and TBM activities.

The major applications of GN mud recycling system covers below field, but not only limited to below:
1) Trenchless HDD Project
2) Bored Pile Project
3) Micro TBM (Tunnel Boring Machine)
4) Diamond Drilling, Water Well Drilling etc

Below are some Mud Recycling desanding plant Models GN can make:
D Series Mud Recycling Models:
1)GNMS-200D Capacity: 200GPM, 50m3/h
2)GNMS-500D Capacity: 500GPM, 120m3/h
3)GNMS-1000D Capacity: 1000GPM, 240m3/h
4)Other models should be customized per clients’ request

Many clients do not know how to choose the right model solids control and drilling waste management equipment to suit for their projects. Below are some comments and suggests from GN Solids Control to help clients make decision. For more assistance, clients can contact GN Solids sales engineers.

1. Shaker screen. To ensure accurate cut point, clients must to choose replacement shaker screens which are confirmed to API RP13C. In order choose the right model replacement shaker screen, firstly clients need to confirmed the shaker model, once shaker model confirmed, screen size is known. And then based on the requested separation point to choose right API size. For different brand replacement shaker screen, the same API size screens are interchangeable.

2. High speed Decanter Centrifuge or low speed decanter centrifuge Package complete with feed pump, connection hoses and control panels.
GNLW363C fixed speed centrifuge is recommended as high speed and low speed operation. It is the most popular size 14 inch decanter centrifuge. Operators can change pulley and belt to get another fixed speed.
Fixed speed centrifuge is easy for operation and maintenance, and its cost is much lower than VFD centrifuge or FHD centrifuge.

3. Screw conveyor Auger transfer for drilling cuttings
GN Solids Control makes screw conveyor with auger diameter vary from 10″ 12’’ 14’’, 16’’ and 18’’. The auger body is equipped with grab wire for emergency stop.
Suggest clients to choose a size auger to min. spare parts stock.
GN augers are combined by standard length 12ft per section. 14” dia. with 36ft transfer length is recommended. You can remove the middle section to use it as 24ft, or add another middle section to use as 48ft.

4. Sludge transfer pump
GN Solids control have various types transfer pump. Clients should tell GN Solids Solids Control their request for model selection, like what is the material for transfer, mud, cuttings, solids, or others? What is the transfer capacity want to reach? What is the transfer length? GN Solids Control has submersible slurry pump, and vacuum pump for solids and sludge transfer, it is driven by air. Users should offer air supplier. It can be supplied by air compressor, or supply air from the rig site. GN Solids Control also makes centrifugal pump.

GN Solids Control makes different sizes mud recycling and mud mixing system for HDD rigs, water well drilling rigs, etc… The popular size includes but not limited to 150GPM, 200GPM, 350GPM, 500GPM, 600GPM, 750GPM, 1000GPM, etc…

GN Solids Control makes different sizes and customized design mud recycling and mud mixing system to suit for clients request.

For example, a client contact GN to inquire a customized water well drilling mud cycling system for 500GPM ~ 1000GPM. The client want a customized mud recycling system equipped with 2 shale shakers, 2 desander mud cleaners, 1 desilter mud cleaner, 1 middle speed decanter centrifuge and the system should be complied with a mixing hopper and mixing pump unit.

The client wants both shale shakers and both desander mud cleaners should have the possibilty to use only one of them if client drill smaller borehole and uses smaller mud pump. GN Solids Control will equip valves at shale shaker distribution pipelines and desander inlet pipes to control the feeding. Clients can choose to use both or either.

2 shale shakers, 2 desanders, 1 desilter and centrifuge feed pump are located on #1 tank.
#1 mud tank will be divided into 3 compartments:
1.1 Both shale shakers feed the first tank.
1.2 Both desander mud cleaners feed the second tank.
1.3 Desilter mud cleaner will feed third tank. It is clean mud tank, Centrifuge feed pump sucks from desilter tank.

Decanter centrifuge, mixing hopper and mixing pump are located on the #2 mud tank.
#2 mud tank (for clean mud) will be divided in to 3 compartments:
2.1 decanter centrifuge tank, which suck mud from 1.3 desilter tank and feed the tank under it.
2.2 clean mud storage tank
2.3 mixing tank with hopper and mixing pump

Mud Agitators and feeding and transfer pumps will be located per needed and per payout.
Third pass to forth via liquid level height.

GN Solids Control is a professional manufacturer to make different sizes Solids Removal Variable Speed Centrifuge includes stand, feed pump and connecting hoses, and other processing equipment and accessory processing equipment before and after decanter centrifuge.

GN Solids Control makes Variable speed from 0 up to 4,000 RPM per different models. GN Solids Control is capacity to make both VFD control decanter centrifuge and full hydraulic drive (FHD) decanter centrifuge per meet clients’ request.
GN Solids Control brand decanter centrifuge is designed with high G-force to get a better separation performance.

GN Solids Control has big bowl decanter centrifuge vary from 18 inch to 22 inch, and max. to 30 inch for big fluid processing rate. In the world, few companies have the capability to make big bowl decanter centrifuge up to 30 inch. GN Solids Control is one of them who have the abilities.
GNLW553 VFD decanter centrifuge is a 22 inch bowl decanter.
GNLW453 VFD decanter centrifuge is a 18 inch decanter.
GNLW363 VFD decanter centrifuge is a 14 inch decanter.
Roughly, for the same conditions, 1 set 22inch decanter = 2 x 14 inch decanter centrifuge.

And 1 set 18 inch decanter = 1.4 x 14 inch decanter. The operators cannot expect to use an 18 inch decanter centrifuge to replace 2 x 14 inch decanter or to replace a 22 inch decanter.

GN Solids Control 14 inch, 18 inch and 22 inch decanter centrifuge can all be used for heavy mud solids control. And also some clients want to use the decanter centrifuge for different applications like for barite recovery, HGS (high gravity solids), LGS (low gravity solids), waste management, and dewatering treatment, or other different applications, the centrifuge features are not all the same. When GN Solids Control makes the design for standard models, GN Solids Control need to balance the performance for all the situations. If clients have fixed applications with the centrifuge, suggest clients to share the information to GN Solids Control sales engineer before order to get and best solution to suit for the projects and maximized the separation performance.

 

GNLW363 FHD centrifuge is a Full Hydraulic Drive decanter centrifuge. It is designed to remove low specific gravity solids from slurries. After the FHD centrifuge separation, the solids are removed and the liquid is returned for recirculation. Like in the drilling mud system, the recovered slurry is drilling fluids, it can be reused in drilling mud system, in waste water treatment system, the recovered slurry is water, which can be reused in the waste water treatment plant. And in some cases, like in the barite recovery treatment, the solids are returned to the active system and the liquid is discarded, or goes to further treatment processing.

GNLW363C-FHD decanter centrifuge is fully hydraulic drive. Th Full hydraulic driven system is imported from leading brand from Switzerland. The bowl speed and conveyer speed of GN FHD decanter centrifuge is adjustable within the permitted range. It can achieve independent, step-less and large-range speed regulation for the bowl and conveying. The bowl speed and conveyer speed during working is showing on the screen.

The advantage of the full hydraulic drive centrifuge is for use in high temperature ambient for heavy mud with flexible bowl and differential speed. The compact one skid design makes it easier for rig up.

GN FHD decanter centrifuge is composed of bowl assembly, collection box, hydraulic drive system, electrical control panel, drive motor, vibration switch (optional), case, base assembly, and skid.

During decanter centrifuge operation, drilling mud or slurry is pumped through the feed tube into the center of the rotating conveyor, where it splashes against the feed accelerator. Screw pump is widely used as feeding pump for decanter centrifuge, besides screw pump, centrifugal pump and submers. The high velocity slurry is then dispersed out four feed nozzles mounted in the periphery of the conveyor cylinder. Rotating at a higher speed than the conveyor, the bowl creates an additional shearing effect, which further increases the slurry’s acceleration. The depth of the slurry in the bowl (pond depth) is determined by the setting of weirs on the liquid bowl head (large end of the bowl).

Recently, a mud cleaning shale shaker, mud cleaner, and decanter centrifuge started to work at an Environmental Protection Company in U.S.A. The Environmental Protection Company in U.S.A. is to collect waste water and waste slurry from different activities, like from drilling, from construction job sites, etc… The company will treat the waste slurry, and cover the water and oil for reuse or resell. The recovered solids, cuttings and particles can be sold again to construction company for building construction, or to build roads.

Below separation equipment in included in the mud cleaning job site for the USA Environmental Protection Company.
The 1st mud cleaning equipment is a Shale Shaker. It is a 4-panel shale shaker utilizing composite material pretension shaker screen. The shale shaker model is GNZS594-HB. It is the most hot sale shale shaker model from GN Solids Control. The shale shaker is widely used in oil and gas drilling, non-oil drilling, and waste slurry separation.

The 2nd stage separation equipment is a 3-in-1 mud cleaner. The mud cleaner model is GNZJ594-2S12N. The 3-in-1 mud cleaner separator is combined of a shale shaker, above the shale shaker, there is a package of desander cone, and a package of desilter cone. The desander and desilter packing are used on top of the under flow shale shaker. The recovered slurry from desander and desilter falls down to the under flow shale shaker, and recovered by the shaker screens which with fine wire mesh. The desander separation is 10 inch which is with cut point 47 microns. The slurry recovered from desander separator will be pumped to desilter separation. The cut point of desilter separator is 27 microns, which is used to further purify the recovered slurry. After desilter separator, the weight of the slurry can be reduced, the solids content is smaller. And the solids size in the slurry is qualified for high speed decanter centrifuge separation.

A high speed big bowl decanter centrifuge GNLW553-VFD is used after mud cleaner separator to remove the ultrafine solids up to 2 microns.

18 inch is a popular big bowl decanter centrifuge which is widely used for drilling mud treatment and drilling waste management. But for different applications, clients’ demands for the output liquid and output solids / soil varies greatly.
For example, when the 18 inch decanter centrifuge is used as solids control equipment in drilling fluids processing system for barite recovery, or for mud weight reducing, big treating capacity is demanded.

The jobsites want to get a big drilling fluids input and output, When the jobsites want to reduce mud weight to a qualified PPG, they want to reach a bigger mud input into the decanter centrifuge, and the output liquid can be reduced the qualified mud weight. But they do not have specified demands for the solids outputs from the decanter centrifuge. For this applications, a bigger conveyor speed (differential speed) can push the input drilling fluids go through centrifuge internal screw propeller faster.

If the mud can pass through the centrifuge internal bowl faster, the total mud volume going through the centrifuge in a certain time is bigger, it means bigger capacity. Furthermore, specified liquid dam boards are used in this application, the purpose is to enlarge the solids output volume. During this operation, the operators can get bigger handling capacity.

But if the big bowl decanter centrifuge is used for dewatering, or used for water / liquid purification, a relative lower conveyor speed (differential speed) and high bowl speed should be used. The purpose is to extend the rotation time of the materials inside the centrifuge bowl, and in order to extend the separation time of the material along the bowl screw. After centrifugal force separation, the purified liquid (maybe water with ultra-fine soil) is discharged from the liquid output port. Soil will settle down along the bowl screw and then been throw out from the solids output port.

In order to choose the right decanter centrifuge model and type, the clients should contact GN Solids Control sales engineer to communicate the material situation for the right model recommendation.

GNSX-450 is a three phase decanter centrifuge. The bowl size of GNSX-450 three phase decanter centrifuge is 450mm (18 inch) diameter by 1800mm in length. It is designed for 24 hours continuous and smooth operation throughout the day. It is mainly composed of driving system, decanter bowl, and screw conveyor inside the bowl, cover box, skid and VFD control panel.

Working principle of GN Solids Control 3 phase decanter centrifuge

GN Solids Control 3 phase decanter centrifuge is mainly designed and made for liquid, liquid and solids separation. GN Solids Control 3 phase decanter centrifuge can also be applied to two immiscible liquids with different specific gravities. When the solids and liquid mixture (raw material before separation) rotates into the high-speed rotating bowl internal the 3 phase decanter centrifuge, the solids and liquid mixture rotates synchronously with the drum. As the reason of the different specific gravity, the centrifugal force of the solids and different liquid is different.

The solid particles which with the larger specific gravity are subjected to the greatest centrifugal force, followed by the heavy phase liquid (such as water) and the light phase liquid (such as oil). So the centrifugal force is becoming less from outside to inside according to the magnitude of centrifugal force. A concentric solid layer and two liquid layers are formed.

The Solids phase inside the mixture will be pushed out by the conveyor impeller of the centrifuge bowl, and liquids are removed from their respective nozzles depending on different gravities. As the reason, GN Solids Control three-phase decanter centrifuge can not only separate the solid from the solids and liquid mixture, but also separate the two-phase liquid with different specific gravity in the liquid and liquid mixture. In this case, Solid / liquid / liquid separation can be achieved.

Besides 3-phase decanter centrifuge for oil field and non-oil field, GN Solids Control has other separation equipment to cater for different application, like shale shaker, mud cleaner, desander, desilter, degasser, transfer pumps, drilling waste management equipment, etc…

Screw pump is also called as Progressive Cavity Pump. A screw pump is a type of rotary pump which is equipped with rotor and stator. The rotor and stator is combined together and rotate within a cylindrical cavity or liner. The fluid or transfer medium enters from the suction side of the screw pump and moves linearly along these intermeshing screws / rotors to the discharge side of the pump.

Screw pump is a popular feeding pump type for centrifuge, no matter for decanter centrifuge, 3-phase centrifuge, or disc centrifuge. Besides screw pump, submersible slurry pump and sand pump are also been used a centrifuge feeding pump. But as submersible slurry pump and sand pump are both a kind of centrifugal force pump, they are not as good as screw pump to feed for decanter centrifuge.

Decanter centrifuge is a high speed rotating device. There will be many self-protection function for safety and also for protect the device. A major self-protection application is over-load protection. It means in case the centrifuge feeding is over load, the centrifuge will be stopped to avoid damaging bearings or damaging rotating component. In this case, the feeding screw pump must be capable to adjust the feeding flow. There are mainly 2 ways to control the feeding screw pump input flow rate:

1) If fixed speed screw pump is used to feed for decanter centrifuge, a VFD control panel is requested to adjust the feeding flow rate to avoid over load, and to reach the better separation performance.

2) If manual adjustable speed screw pump is used as decanter centrifuge feeding screw pump. Fix speed control panel can be used for the pump for start and stop.

Furthermore, as the decanter centrifuge has self-protection function in case of overload. To avoid damage the centrifuge, there must be an inter-lock connection between the centrifuge control and the feeding pump control. In case the centrifuge is stopped, feeding pump can be stopped immediately. And the screw pump cannot be started until the decanter centrifuge is running stably.