Desander Desilter

As an oil sludge treatment system supplier in China, GN solids control also provide customized oily soil treatment solution. Recently one set of customized Oil Contaminated Soil Washing and Separation system are ready for shipment to our customer. Before feeding to standard oil sludge treatment system, we need to broke the solids into small pieces and mining separation shaker to screen the coarse solids and wash the solids so that the oil sludge became fluidity for easy separation by the oil sludge treatment system.

The crushed solids can be transferred by solids vacuum pump and be diluted in the pre-mixing tank and adding proper chemicals, agitating and mixing, the oil sludge will be transferred to screening module by submersible slurry pump. The solids vacuum pump is 100% air operated pump which needs an air compressor to supply air, it can be operated with automatic mode or manual mode according to their requirement.

There is an separate chemical dosing module to add chemicals in the pre-mixing tank and feed the chemicals to decanter centrifuge and 3 phase disc separator, the automatic chemical preparation and dosing unit is used in the preparation, storage, and dosing of powder chemicals. The single barrel manual dosing system is commonly used for manual injection of chemicals, which has the basic function of continuous and stable dosing. Both of the barrel dosing system and automatic chemical dosing unit are installed inside the container for reliable operation and for sun/rain proof.

The main separation components is the centrifuge separation module, including solids liquid separation decanter centrifuge, 3 phase separation disc separator for oil and water separation. The recovered oil is collected into buffer oil tank, the treated water is stocked into water tank, which can be used in the circulation system. The discharged solids will be collected by waste container for further treatment or final disposal.

One set of customized mud tank system is ready for shipment to Middle East. The ATEX certified motor and electric control system can be applied for offshore drilling rig solids control system. The mud tank system is composed of 1 ea shaker tank, 2 ea storage tank, 1 ea water tank, 1ea of pump skid and 1 set of electric control system.

The main equipments of shaker tank including 3 sets of linear motion shale shaker and 1 set of hydrocyclone assembly, 2 sets of mud agitator, 4 sets of mud gun. The linear motion shale shaker is a 4 panel screen shale shaker with 585x1165mm shaker screen. We can produce different API from API 20 to API 325 as per client’s requirement. The drilling fluids from well head flow to fluids distribution box and evenly flow to shale shaker for primary solids separation, the desander cone and desilter cone assembly installed on top of the 3rd shale shaker as the 2nd phase separation and 3rd phase separation equipments, the feeding pump are installed on the pump skid, and the suction and discharge pipeline are connected. The standard mud cleaner with compact footprint is without buffer box, when it is used as back up shale shaker, an extra buffer box will be added, and the hydrocyclone assembly frame will be installed on top of the shale shaker.

The 2ea mixing hopper , 2ea mixing pump, 2 ea centrifugal pump and a special designed collection hopper will be installed on a skid, the mixing pump can be also used as transfer pump, for longer working life, the pump housing and impeller are made of hard ductile iron alloy for better abrasion resistant capability, the mechanical seal to provide zero leakage and longer operation life. For more details, pls contact with GN solids control.

Mud agitator is drilling mud agitating and mixing equipment of solids control system. All the mud tank compartments except for sander trap should be agitated to avoid solids deposition at the tank bottom and maintain a consistent mixture throughout the surface system. The mud agitator use an electric motor to drive single or double impeller blades which flow the mud in a pattern throughout the mud tank. The mud agitator prevents settling enhances the efficiency of solids removal equipmnets, such as shale shaker, desander, desilter, decanter centrifuge, degasser, etc.

According to the mud weight, mud tank dimension, mud tank design ( round or square), mud agitator qty, desired turnover ratio ,the user will select proper size impeller, agitator qty, motor and even impeller qty ( single layer or double layer). If the agitator model and qty is not proper used, it will lead overheating and over current and lead over torque to damage the mud agitator. The main components of the mud agitator including electric motor ,gearbox, mounting plate, agitator shaft, impeller, and stabilizer, there are direct connection and coupler connection based on different requirement. Based on different type gearbox, there are helical bevel type gearbox and worm wheel type gearbox. Based on mud tank dimension and remained room, there are horizontal type mud agitator or vertical mud agitator. Based on different ambient temperature, the required gear oil is different. If the gearbox oil temperature exceeds the upper limit or the motor temperature exceed 95℃, and there is vibration and abnormal noise, the user should stop the agitator immediately for inspection.

GN produced mud agitator utilized heavy duty helical bevel gearbox, direct connection, horizontally installed, which is with compact size, reliable operation, low noise, good mixing performance, the explosion proof motor can be CNEX, ATEX or IEC EX standard to meet different explosion proof standard.

As a manufacturer of solids removal unit in China, GN produced solids control/ removal unit has been widely used for mineral engineering projects. More and more clients start to realize that the solids removal unit’s usage will take a lot of advantages to the users.

1. The Solids removal unit will reduce the water consumption and reduce the drilling cost significantly
2. The solids removal unit will reduce the wear on drill components and protect the drilling rig, it will extend the drilling rig service life effectively
3. The solids removal unit can reduce the drilling waste and lower the waste disposal cost and environmental management cost
   Anyway the investment on the solids removal unit will be another consideration compared with the direct cost savings and potential cost savings, it is not easy to clear the potential cost savings. The client may select to rent the solids removal unit for a short term project, for a long term mineral projects, to buy a solids removal unit is an economic way.
4. 
   GN Solids Removal Unit including fluids picking up pump ( it will be installed in the mud pit vertically to pick up drilling fluids from mud pit to shale shaker), shale shaker( to removal coarse solids and reduce solids content to let the drilling fluids suitable to be treated by decanter centrifugue), decanter centrifuge ( mechanical separation cut point is 5 microns) and feeding pump, mixing hopper, mixing pump and mud tank. The clean fluids treated by decanter centrifuge will be mixed with chemicals and pump back to drilling rig. The electric control system can control all the motors and starter of all the equipments. A generator can be installed on the solids removal unit skid as power supply.
   For more information of the solids removal unit, pls contact with GN solids engineer.

As a manufacturer of solids control equipments and waste treatment equipments in China, GN Solids Control can provide customized solution for oil sludge treatment, oily soil treatment, drilling waste treatment. Soil pollution mainly come from oil & gas drilling, production and processing process, including oily sludge, drilling waste, oil sewage, and also produced during crude oil storage, transportation and processing, etc. contaminated soil. GN designed oily soil treatment system can achieve oily waste reduction treatment which will greatly reduce the total amount of oily waste and reduce the cost of subsequent harmless treatment. The oily soil waste treatment result can be recovery oil (Basic Sediment and Water in oil is less than 3% with proper chemicals), discharged solids ( oil content is below 2%) and water (which can be reused in the treatment process). For the contaminated soil washing process, firstly the contaminated soil should be grinded , crushed and separated the coarse solids, then washing process will be applied, the oily soil treatment is after the contaminated soil washing process.

The customized oily soil treatment solution including crushing pretreatment, material pre-mixing treatment, scrubbing pulping, first phase separation treatment double deck coarse shale shaker GNZS706F and mud heating and diluted, fine solids removal shale shaker GNZS594F separation, three phase decanter centrifuge GNSX554E-VFD with chemical dosing unit to separate oil, water and solids. The chemical dosing unit can add both dry powder chemicals and liquid chemicals. The three phase decanter centrifuge is based on the weight difference of solids, oil and water.
Due to the difference of specific gravity, the centrifugal force is different. The solids with the largest specific gravity and produce greatest centrifugal force, the water is the heavier phase liquid, the oil is the lighter phase liquid.
For the detailed working process, pls contact with GN solids sales.

To confirm if 2 phase separation decanter centrifuge can be applied for drilling fluids cleaning/ waste water treatment/ solids liquid separation project.
firstly we need to clear the pre-conditions of separation: 1) density difference (Layering inside the bowl) 2) rotary speed difference/ differential speed ( the solids and liquid can be discharged separately)

secondly we need to clear the material feeding requirement of decanter centrifuge: 1) solids content < 20%; 2)solids size < 500 microns, if not, the user could use pre-treatment equipment for primary separation, normally shale shaker, the user can use different mesh size shaker screen to control the solids content and solids size. Without adding chemicals, the centrifuge mechanical separation cut point is 2~ 7 microns.
The decanter centrifuge main components including bowl assembly, fluids collection box, main motor, back drive motor, cover, skid, inlet pipe, flushing port, fluids discharge port, gearbox, pulley with belt. The main motor drived the bowl through pulley and belt, the back drive motor drived the screw through pulley and gearbox. The bowl and screw with same rotary direction, different rotary speed, the differential speed generates. The VFD control panel with main motor, back drive motor and pump motor 3 VFD, the user can adjust the frequency of the 3 motors through PLC smart control and HMI interface. The engineer can use different frequency according to drilling fluids condition. The fluids pond depth can be adjusted as per requirement, to control the discharged solids moisture and treating capacity.

The decanter centrifuge working principal is as below:
The high speed rotating bowl generates a strong centrifugal force and sticks the solid particles with higher density on the inner wall of the bowl to form a solid layer: due to the low density of liquid, the centrifugal force is small, the liquid layer is formed inside the annular layer.

I don’t agree with that who say drilling cuttings are good for drilling fluids, he doesn’t realize the dangers of drilling cuttings to drilling fluids. The phenomenon that drilling cuttings increase the solids content of the drilling fluid will not be discovered very soon. The occurrence of this hazard has a certain process, so the increase in cost will not appear soon. I think that the cuttings will increase drilling costs, damage the reservoir, and increase the cost of drilling fluids treatment. During the drilling process, the solid phase in the drilling fluids is disposed of by the surface solids control system, after adding appropriate additives to make the drilling fluids meet the required performance specification, it is pumped into the well again, which is the meaning of the solids control system.

Shale shaker is the first phase solids cleaning equipment to separate big drilling cuttings, according to the drilling depth and required mud treatment capacity, the user can use 2 units shale shaker, 3 units shale shaker or 4 units shale shaker for option. The desander cone is the second phase cleaning equipment to separate solids size bigger than 45 microns, the desilter cone is the third phase cleaning equipment to separate solids size bigger than 25 microns. The user can use separate desander, desilter which without bottom shaker, or desander , desilter with separate mini bottom shaker, or mud cleaner with desander cone, desilter cone and bottom shale shaker 3 in 1, the discharged drilling cuttings will be much drier and drilling waste volume can be reduced.
Decanter centrifuge is the fourth phase cleaning equipment, the separation cut point is 2~5 microns.
The good solids control equipments can reduce drilling waste and recovery more drilling fluids, if you have any requirements of solids control equipments, pls contact with GN solids control.

A drilling fluids treatment decanter centrifuge consists of a centrifuge bowl, screw, electric motors, gearbox, feed tube, solids discharge trough, fluids outlet port, bearing block, Ex control panel, cusions, telescopic skid or supporting legs. A decanter centrifuge used in drilling fluids treatment system is typically used to :
1)    separate fine solids up to 2 microns, to keep the drilling fluids balanced
2)    separate barite from used drilling fluids and reuse it
3)    dewatering the hydrocyclone underflow

As a decanter centrifuge manufacturer in China, GN solids control can produce decanter centrifuge models as below:
1.    drilling mud processing decanter centrifuge:
14 inch bowl decanter centrifuge GNLW363D for low gravity separation
18 inch bowl decanter centrifuge GNLW453D for low gravity separation
18 inch bowl decanter centrifuge GNLW452D for barite recovery
2.    diamond core drilling waste water treatment
9 inch bowl decanter centrifuge GNLW223D and GNLW224ET-VFD
3.    oil sludge separation, mud dewatering, solids liquid separation
14 inch bowl decanter centrifuge GNLW363D, GNLW364ET-VFD
18 inch bowl decanter centrifuge GNLW453D, GNLW454ET-VFD
22 inch bowl decanter centrifuge GNLW553D, GNLW554ET-VFD
30 inch bowl decanter centrifuge GNLW764A-VFD
To achieve better separation performance, hydrocyclones separation should be used before decanter centrifuge. The desander cone separation cut point is 45 microns, the desilter cone separation cut point is 15 microns, the solids content is reduced relatively then the fluids are transferred to decanter centrifuge.
For VFD decanter centrifuge, the G force can be adjusted by input different frequency ( to adjust the rotation speed) when bowl diameter is fixed. The high G force up to 3000G will reduce solids conveyance due to torque limitations. The higher of the G force, more solids will be settled in the bowl, more torque is required to move the solids out, until torque limitation is reached, the centrifuge stopped working due to torque protection.

Screw conveyor is normally used to transfer the drilling waste from solids control equipments to vertical cuttings dryer or high G drying shaker, or collect drilling waste from collection hopper and transfer to other place. The main components including: motor, coupling, gearbox, cover, hanging bearing seat, header of the driving end, screw shaft, blind flange, housing assembly, etc. The drilling cuttings is fed into the screw conveyor and transferred along with the rotating screw, the screw is sealed inside the trough by a hinged metal lid which is bolted down for safety, the feed port and discharged port can be designed as per client’s requirement.

Maintenance of the screw conveyor:
Compared with sludge vacuum pump, the operation and maintenance of the screw conveyor is easier, the vacuum pump operation need air compressor for air supply, the valves need to be checked regularly, the inlet hose and discharge hose length will be customized according to suction and discharge length required. The suction depth should be within the limit to ensure the performance of the vacuum pump. The maintenance of screw conveyor including bearing lubrication, gearbox oil level checking and gearbox regular checking, oil seal replacement, electric motor checking, etc. Under different ambient temperature, the grease lubricated should be used for different model. The screw conveyor can be installed horizontally or declined by installed different support frame. It can be installed under the solids control primary shaker along with shale shaker tank, the drilling cuttings are transferred by screw conveyor to the 2nd screw conveyor , which is installed slantly, it will transfer the drilling cuttings to vertical cuttings dryer or high G drying shaker.

The user can select to use screw conveyor and sludge vacuum pump depends on its location and area dimension, sometimes both of them can be used together.

Linear motion shale shaker sometimes are required to treat the drilling fluids uphill or downhill, they all have an easy screen deck angle adjustment function to optimize mud throughput and cuttings conveying speed. The upward angle of the shaker deck prevents the overflow of mud caused by the influx of mud from the wellhead manifold. When the shaker deck angle is greater than 3º, it will be a problem for solids discharge. The mud throughput increases with the upward slope and the delivery decreases. For solid material conveying, solids discharge is slower than liquid fall due to viscous resistance and pressure differential on cuttings load. If the shaker deck angle is too high, even during operation, a large amount of solids will accumulate on the screen surface, causing the screen to block, resulting in drilling fluids overflow. Shaker Vibration and increased residence time of the mud results in better treatment, drier solids discharge, and cleaner treated liquid, which can be used to prepare new drilling fluids and reused by the drilling rig.

GN solids control produce linear motion shale shaker with different screen panels with different treating capacity, by using proper screen deck angle, and different screen mesh, the user can control the shale shaker separation performance according to their requirement. GNZS703F shale shaker deck angle adjustment range is -1°~+5°. We have 2 panel shale shaker GNZS752F, 3 panel shale shaker GNZS703F, 4 panel shale shaker GNZS594F, all of them are single deck linear motion shale shaker, also we have GNZS706F double deck shale shaker, we can produce customized dual motion shale shaker, including linear motion and elliptical motion. The shaker installed 4 sides pre-tensioned composite material frame shaker screens from API 20 to API 325 for option.
If you need linear motion shale shaker, pls contact with GN solids sales.