Drilling Mud Recycling System

Recently one set of oil sludge treatment system is ready for shipment to a oilfield environmental solutions company with customized painting color. GN solids control can design and produce standard oil sludge treatment system with different treating capacity 1m3/h, 5m3/h, 15m3/h, also we can design as per client’s concept and technics process.

A standard oil sludge treatment system is consist of the modular below:

1. Waste transfer unit: GN use our own solids vacuum pump to transfer the oil sludge from the waste pit to pre-mixing modular. The features of vacuum pump: (1)100% air operated pump without using electricity power, need air compressor for air supply. The user need to prepare one air compressor to provide air for both vacuum pump and the positive pressurized VFD control panel of the decanter centrifuge.
   (2) can be adopted to different types of oil sludge, heavy duty for continuously working
2. 
   (3) automatically and manually working for option for different requirement
   (4) max discharge distance is up to 1000m, max suction distance is 50m, it can used into the crude oil tank without labors in, it is user friendly pump to transfer the oil sludge out of the crude oil tank bottom.
   2 pre-mixing modular: including a pre-mixing tank equipped with heating lines inside the tank wall, when the user supply hot steam to the heating lines, the oil sludge will be heat to 60 degree for easier separation in the next separation step. Mud agitator with control panel to agitate the oil sludge with necessary chemicals and keep it flowable. The submersible slurry pump will transfer the pre-mixing oil sludge to the next process- coarse solids separation modular.
   3 coarse solids separation modular: it might be removed depends on if there is coarse solids in the oil sludge.
3. fine solids separation modular for solids/ liquid separation by using VFD decanter centrifuge, and working together with chemical dosing system
4. 3 phase centrifuge modular to separate oil from water.

GNLW554EP is big bowl big volume decanter centrifuge with bowl diameter 22 inch and L/D ratio 4.2. It is the ideal decanter centrifuge for dewatering unit, it can be also used for oil sludge treatment system. The technical specification is as below:

Centrifuge model: GNLW554EP-VFD
Bowl diameter: 22 inch (550mm)
Bowl length: 91 inch (2310mm)
Designed capacity: 600 gpm (136m3/h)
Typical capacity: 480 gpm(108m3/h)
Max bowl speed: 3150 rpm
Typical bowl speed: 0~ 2800 rpm
Max G force: 3051G
Typical G force: 0 ~ 2412G
Cut point: 2 ~5 microns
Differential speed: 0 ~45 rpm
Gearbox Torch: 12000 N.m
Gearbox ratio: 35:1
Main motor: 90KW (120HP)
Back drive motor: 45KW (60HP)
The max capacity is measured for water, it will be various as per different material conditions, like oil sludge, dredging slurry, drilling waste, drilling fluids, industrial waste water, etc.
The decanter centrifuge can be drived by VFD control panel, which is positive pressuried VFD control panel with PLC smart control and touch screen , 3 motor VFD, main motor, back drive motor, pump motor, self cooling system or external air conditioner for suitable environmental temperature -20~+40℃ or -20~+55℃.
The centrifuge features is as below:
1) The bowl of GN centrifuge is made from Duplex Stainless Steel SS2205 or SS2304 by centrifugal casting which is better than SS304 or SS316.
2) The solids discharge port is made from Tungsten carbide inserts, The mud distribution port is made from Tungsten carbide inserts, the anti-abrasion will extend the life for heavy mud anti-abrasion will extend the life.
3) 3 Stage balancing process to maximize the balance of the centrifuge include 1800RPM low speed balancing and real operation high speed balancing as well as the assembly balancing.
4) The Screw is protected by interchangeable Tungsten Carbide Tiles for longer life and easy maintenance.

As one of the most professional HDD mud recycling system in China, we can design and produce mud cleaning & mixing unit with different treating capacity as 200gpm, 350gpm, 400 gpm, 500gpm, 600gpm, 800gpm, 1000gpm, 1500gpm, also we can provide customized design mud recycling system as per client’s requirement. Below is the 200gpm mud system photo we shipped recently to our HDD industry client.

The working process is as below:
The submersible slurry pump pick up the used drilling fluids from the waste pit to desilter with double deck shale shaker: the first phase is bottom deck shale shaker to separate coarse solids so that the drilling fluids can be feed to desilter cone properly. The centrifugal pump feed the clean drilling fluids to desilter cone to separate fine solids with cut point 2~5 microns, the clean drilling fluids drop down into the mud tank, the user can add powder chemicals into the venturi hopper, the mixing pump provide proper pressure to help mixing evenly. The clean fluids are ready for recycling in the mixing compartment. The mud agitator and mud gun are agitating the fluids to prevent the solids suspension in the tank bottom.

The technical configuration is as below:
1) 1 unit of GNZY753F-Y4N mud cleaner ( double deck shale shaker + desilter cone), all the shaker screen installed on the mud cleaner is composite material shaker screen, the desilter cone is 100% polyurethane material with better wear resistance material.
2) 1 unit of feeding pump
3) 1 unit of mixing pump
4) 1 unit of mixing hopper
5) 1 unit of 2 inch mud gun
6) 1 set of mud tank with tank accessories, with electrical control system and lightings
Another unit of 200gpm mud system under production for the same client, last year they purchased 3 sets of 600gpm mud system.

Below is the photo taken at site of GN oil sludge treatment plant in China. We have 3 standard model of oil sludge treatment plant with treating capacity 1m3/h, 5m3/h, 15m3/h. Also we can make customized design for client’s special requirement. The technical configuration of a standard oil sludge treatment plant including:

1) Oil sludge transfer modular: we use vacuum pump to take the oil sludge from the waste pit to pre-mixing modular.
2) The pre mixing tank equipped with heat lines around the tank wall inside, the operator need to supply hot steam or hot water to the heat lines to remain the oil sludge temperature up to 60℃, it will increase the flowrability of the oil sludge for better separation of solids and easier to be transferred by the submersible slurry pump to shale shaker modular. The operator should add chemicals according to the oil sludge material conditions, the purpose to add demulsifiers is to make it easily break from solids, so that the further process shale shaker and decanter centrifuge can separate the oil easily. The mud agitator will mix the chemical with oil sludge evenly.

3) The shale shaker modular will separate the coarse solids from the oil sludge, the solids will be collected by waste container, the shale shaker is closed by cover to prevent it from splash, and internal spray system to flush the screens in case of blinding the screens because of high viscosity. The oil sludge will drop down into the mud tank and transfer to decanter centrifuge modular by screw pump.
4) The decanter centrifuge working together with dewatering unit will separate the fine solids from the oil sludge, the fluids will flow to the intermediate tank , then the diaphragm pump will transfer the mixture fluids to 3 phase centrifuge to separate oil from water.

Last week we shipped one batch of centrifugal pump and decanter centrifuge to our Russia client, this is the repeat order from our client. The centrifugal pump is a multi function pump which can be widely used for oil and gas drilling solids control system and all the other solids and liquid separation system. In solids control system, centrifugal pump can be used as desander and desilter feeding pump, vacuum degasser jet pump, trip pump for trip tank, mixing pump, charging pump of mud pump, transfer pump.

GN brand centrifugal pump features:
1） The wear parts-impeller, pump casing is made of wear resistant material: hard ductile iron alloy,which is much stronger than grey steel, grey steel has been widely used by many other centrifugal pump manufacturers in China, it is important to know the materials to be used clearly.
2） All the pump parts are 100% interchangeable with world famous brand centrifugal pump, we can provide interchangeable spare parts for client’s old centrifugal pump
3） Mechanical seal for longer working life.
4） All bearings from FAG for reliable operation, not cheap brand bearing.
5) The skid for supporting pump and motor is made from casting instead of welding to provide reliable operation.

The decanter centrifuge will be used to treat drilling fluids, to separate the fine solids from the drilling fluids and reused to prepare for new drilling fluids for recovery. The decanter centrifuge can be installed with different speed pulley for different application, when 2200rpm pulley is used, it can be used for barite recovery, when 3200rpm pulley is used, it will be used for low gravity solids separation.
The impeller of screw is protected by tungsten carbide tiles for longer working life and repairable, the bearing is made of SKF brand, the bowl material is made of duplex stainless steel 2304.