Drilling Fluids shale shaker

Vertical rotating drilling rig is the normal machine used in piling project. During the drilling process, in order to protect the inner wall of the drilling hole and speed up the process, the operator always chooses to use drilling mud. Then here comes another problem how to reduce cost of the drilling mud thereby to reduce the cost of drilling. The solution is to use mud recycling system to make the drilling mud reusable.
The purpose of the mud recycling system is to remove the large size solid particles in the drilling mud by several separation machines. In regards to the mud recycling system for piling project, it could be a very compact design as separation process is not so complex as that for oil gas drilling. GN solids control is one of the most experienced separation solution providers who could provide the mud recycling system for almost all the industries will use it. GN already developed the standard mud recycling system especially for the piling project.


De-sanding Unit

Strictly speaking, the mud recycling system used in piling should be called de-sanding unit as the drilling depth is normally shallow and most of the solid particles are sand. A de-sanding unit would be enough for processing the separation to get the expected reusable drilling mud.
GN’s de-sanding unit is a compact structure 2 steps separation system. The main equipment in this de-sanding
unit is combined with a 2 layers shaker and cyclone manifold. The double layers shaker is used for coarse solids separation by the under layers and the upper layer screen is for drying the slurry discharged from the cyclone unit. The tank under the shaker unit is used to store the drilling mud. One centrifugal pump is installed in the system for transferring the mud to the cyclone unit for sand separation.
This de-sanding unit could be connected with extra mud tank for larger capacity mud storage. The operators can also equip a jet mixing unit to make an self-contained mud recycling system for other drilling project like HDD and water drilling.

Mud system will not work if there are no mud tanks. In the mud recycling system, the tanks are used to store the drilling mud to be a base where the solids control equipment to be installed. Normally, more than one mud tanks
will be used in the oil drilling mud system. For different purpose, the design of the mud tank is different, especially the inner structure of the mud tanks.
There are mainly 3 types of mud tanks recycling tank, intermediate tank and premixing tank. Then what are the different among these 3 types of mud tank?
The recycling tank is where to install the primary shakers and degasser unit, and also the de-sanding and de-silting unit. Each of equipment needs a compartment in the mud tank. As the recycled drilling mud is treated by the solids control equipment one by one. After treatment by each of the equipment, the drilling fluids will be cleaner than before. Thus the drilling fluids cannot be mixed. The wall between two compartments always has an overflow port for balance of the drilling mud in the tank.


Mud Tank System

For the tank to install the de-sander and de-silter unit, inner structure of the mud tank would be much complex as there are pipes for centrifugal pump to such the drilling fluids from inside of the tank and transfer to the cyclone for further treatment. Operator has to know which pipe is for de-sander and which pipe is the desilter.
On the mud tanks for installing the solids control equipment on, there always have the walkways and handrails. The walkways provide enough space for the operator to walk around the equipment for operation and maintenance. Intermediate tank is a type buffering tank, part of this tank is for mud recycling, and other parts are used for mud storage. Operators can easily tell how many compartment in this tank.
The premixing tank is used to mix drilling fluids. It always is connected with the jet mixer unit. The mixing pumps suck liquid from mud tank and send liquid back again with added mud materials from the hopper. Thus the pump should be able to suck the drilling mud from anywhere in the mud tank used for mixing and storage.
Therefore, in the mixing tank, there are two groups of pipelines, one for sucking, and the other one is for sending liquid back. Mug agitators and mud guns are always installed on the mixing tank.
Though, the inner structure of the above tanks is different, the outer dimension and design are always the same for purpose of easy transportation and assembling.

In the just past MinExpo 2016 exhibition for especially for mining industry, GN showed the 9 inch decanter centrifuge there and many visitors came to GN booth showing great interesting to this unit.
9 inch is the smallest size model in GN’s decanter centrifuge production line. GNLW223 is the typical model number of this size, now both the fixed speed and VFD model available. At this time, all GN’s decanter centrifuge is electric driven; however, GN is researching the FHD model that is more preferred as less energy consumption.


GNLW223 Decanter Centrifuge – 9 inch

GN 9 inch decanter centrifuge unit can run normally at 3800 RPM for long time working condition, while the designed maximum RPM is 5000. GN’s dynamical balance testing instrument can test the decanter centrifuge at actual working speed, even the maximum designed RPM. This ensures the stable working performance.
GNLW223 series decanter centrifuge is mainly used for small capacity solids removal project. Diamond core drilling is a typical industry that will use this type decanter centrifuge. With a high working speed, the centrifuge unit would remove the ultra fine solids like less than 5 microns from the drilling fluids. Ceramic tiles are inlayed for protection of the screw propeller, which extends the working lifetime. For the customer who prefers the FHD model, GN also provides only the mechanical part like bowl assembly and bearing seat, customer could equip the hydraulic driving system and electric control system locally.
Some mining operators would ask put a shaker unit before the decanter centrifuge, thus the coarse solids could be removed firstly. Then the slurry with fine solids will be fed into the centrifuge. The function of the shaker is to remove most of the large size solids, which will greatly reduce the working load of the centrifuge. It is also a protection on the centrifuge unit.
Now GN already developed the compact solids removal unit including mini shaker and 9 inch decanter centrifuge. This system also has mixing system for adding bentonite into the fluids. Its compact structure make it could be helicoptered to lift to a remote area for working.

Diamond core drilling is a type of drilling used to get the stratum samples so that the geological experts could analyze what under the ground, and if there is mineral reserve, how deep need to be drilled for exploitation. Diamond core drilling always uses tube type drill bit for getting a cylinder earth sample. The drill hole is not too big to use plenty drilling mud. However, on consideration of environmental protection, the recycling of the
drilling mud is firmly requested, which is also a method of cost saving.

gn-solids-removal-unit (1)

GN Solids Removal Unit for Diamond Drilling

The drilling mud recycling system of the diamond core drilling can also be called as solids removal unit. As the drilling site of diamond core drilling is always space limited. The solids removal unit needs to be as compact as better. GN has 2 equipments that are made especially for diamond core drilling: Mini shaker and Mini centrifuge unit.
GN Mini shaker is 2-panel screen design with vibration G force up to 7.1 that is used to remove the coarse solids in the drilling fluids. Heat treatment on whole shake deck greatly strengthens the deck to ensure a better performance on drying the solids.
GN Mini centrifuge is 2-phase type for solids and liquid separation, 9 inch bowl diameter, with speed up to 3800RPM, the centrifuge could effectively remove the solids with size of 2 microns in the mud. Stainless steel material of the bowl guarantees the good working for all kinds of chemical liquid. The protection of tungsten carbide tiles on screw and ceramic casing at solids discharge port significantly extends the life time of the centrifuge.

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GN 9 Inch Centrifuge

The mini shaker and mini centrifuge could be ordered separately as well as included in GN’s solids removal unit. By fixing the shaker and centrifuge unit on a tank, GN could provide clients a very compact mini mud recycling system-SRU. GN SRU can also do the job for re-configuration the drilling mud. GN also has modular type solids removal unit which is transportable by helicopter to remote area.
GN solids removal unit could greatly decrease the solids content in drilling mud so that to make the drill bit down hole perform well. It could greatly reduce the consumption for water and drilling mud, which is a large saving and benefit for environment. GN now has brochure especially for solids removal unit, any interests, please feel free to contact with GN.

The persons who know solids control equipment may know well on the shale shaker and mud cleaner unit. These 2 machines are very common in solids control system that do solids separation job from the first to forth stage. The shale shaker is located at the very beginning of the mud recycling system for primary solids control; the coarse cuttings could be removed by the shale shaker. While after treated by the shale shaker, the drilling fluids would be transferred to the mud cleaner for further treatment.
For the purpose of easy maintenance, in the same solids control system, the mud cleaner is equipped with under drying shaker that is same model as the primary shale shaker. Mud cleaner is just a machine on which the cyclone frame was fixed above. The mud cleaner unit is only able to be used to separate the solids via the hydrocyclone units. Why the mud cleaner unit cannot be used as a shale shaker even if it has the under drying shaker? This is really a good question. GN’s engineer equipped a logging tank to the mud cleaner unit and the mud cleaner unit becomes a shale and mud cleaner composition unit.


GN Shaker & Mud Cleaner Composition Unit

Normally, GN’s shaker unit has back type logging tank that is used to collect the drilling fluids coming out from the drilling hole. The drilling fluids accumulated in the logging box firstly and then overflow into the shaker deck, thus the shaker screen will not be damaged by the high pressure drilling fluids. This unit could be used as a shale shaker unit.
De-sanding and de-silting cyclone are installed on the mud cleaner for finer solids separation. The solid discharged out from the bottom nozzle of the cyclone also has high pressure that will shorten the screen life if directly dropped onto the screen surface. To avoid this situation, there is a hopper collection box that is used as buffer between the cyclone and screen. To make this machine compact, GN’s engineer designed to insert the buffer box into the logging box, which means the logging box is also used as second buffer box for the cyclone unit. This is the function of mud cleaner.
One thing need to be noted is this shaker and cleaner machine can only be used for one function one time: either shaker or mud cleaner. This is a cost saving unit with small footprint, for some project not very urgent, this unit could be a very ideal choice. GN ever showed this unit at Beijing CIPPE, much attention was attracted there.

GN’s decanter centrifuges are 2 phase type and mostly used in oilfield for drilling fluids fine solid particle separation and waste management as GN is known as a China leading professional manufacturer for solids control equipment for oil & gas industry. However, according to the working principle, the centrifuge should be able to be used in some other industry for liquid and solids separation just like the dredging slurry separation and construction site solids removal.
GN ever sent one solids removal system including shale shaker and decanter centrifuge to London for the construction project there. On the construction site, the worker may use water to wet or mix some construction material. Nowadays, most of the office building has parking area at the ground floor of the building. When the beginning of building, the workers will operate the rotating drilling machine to drill some holes on the ground for piling. This type of drilling will also need water for cooling down the drill bit and take out the drilling cuttings from bottom of the drilling hole.


Solids Removal Unit

GN’s solids removal system is used to separate the solids and liquid. On construction site, it will be used to remove the stone and other large size solid particles from the water. The unit sent to GN’s customer in London was a 2 phase solids control system. The configurations are as below:
1 unit shale shaker with 3-panel screens for primary solids control could remove most of the large size solid particles. The solid particles on construction site would be various from sand, stone, leaves and waste cans. The shaker could remove almost all the coarse particles by using the wire mesh screens.
1 unit decanter centrifuge with speed up to 3200 rpm is used for fine solids separation. GN’s centrifuge is made of excellent material on bowl and screw propeller for long lifetime and easy maintenance.
1 mud storage tank is divided into two compartments for sand trap under the shale shaker and clean liquid collection under the centrifuge. 2 pumps are installed on the tank skid. One of the pump transfers the slurry from sand trap compartment to the centrifuge, another one is used to transfer the liquid out from the tank for reusing.
GN’s mud tank system is with the CE certificate thus the clients from Europe could use GN’s mud system freely without worrying about the compliance. For any request, welcome contact GN for more information.

De-sander is very popular equipment used in solids and liquid separation processing. It always contains cyclone unit and steel frame. With different diameter of the cone body, this cyclone unit could separate the solid particles with different sizes. GN’s de-sander is using 10 inch cyclones which could remove the solids size down to around 45 microns.
GN’s de-sander unit is used in drilling industry to separate the drilling cuttings from the drilling fluids. Traditional de-sander units don’t have the under drying shaker for maximum recovery of the drilling fluids liquid, thus a large amount of valuable drilling fluids was lost. However, this type de-sander and even the de- silter unit are very simple structure and cost effective.

gn de-sander unit

GN De-sander Cleaner

To make the discharged solids much dryer, GN prefer to suggest choosing the de-sander unit with a under drying shaker which could recycle much more drilling fluids. This could reduce the waste discharges to environment and the cost on drilling fluids materials. GN has a de-sander model with under drying shaker of 2 layers screens panel. This unit is functioning as both primary shale shaker and de-sander unit. The drilling fluids gets into this de-sander unit via the mud distributor pipe and then flow on the bottom layer screen firstly for primary solids control. Liquid gets through the screen mesh and falls down to the under located mud tank. Large size particles will be discharged out of the shaker. And then the liquid will be transferred by a centrifugal pump unit to the de-sander cyclone unit for fine solids separation. The mixture of liquid and solids discharged from the cyclone will come to the upper layers screen for drying processing. Here, to prevent the damage of screen mesh resulted by the strong impact force of solids discharged out from the cyclone unit, GN designs small buffer box to cover the outlet of the cyclone. This buffer box is small enough to make the unit more compact.
GN’s double-layer screen panel shale shaker can also be used as only primary shaker for much fine solids separation. Besides de-sander unit, de-silter unit can also use this type shaker as drying shaker.

Shaker screen users may know that there are flat type screen and pyramid type screen used very often on the shale shakers to separate the cuttings from the used drilling fluids.
The flat type shaker screen are very common in screen application, with 3 layers wire mesh stacked and closely connected with the steel back frame. Always there are hook strip type and steel tube frame type screen. Different from the flat type screen with a flat shape screen panel, the pyramid type screen is designed three dimensions screen panel like a wave. This pyramid screen design firstly issued by the world No. 1 solids control equipment manufacturer of Derrick Equipment. And they do have patent for this design.


GN replacment pyramid creen

Comparing with flat type screen, the pyramid type screen has below several advantages.
1. Make a larger effective screen area. Due to the wave type with top and troughs, in fact, the screen panel has a larger screen area than the flat type if the screen panels have same width and length. The pyramid screen let more drilling fluids distribute on the screen and more fluids will with solids less than the mesh will go through the screen.
2. Under the G force and gravity, the solids will accumulate at the troughs of the screen. Comparing with the flat type screen with solids distribute uniformly on the whole screen panel which will impede the go though the screen, the pyramid screen has the wave top and slopes at both sides will let drilling fluids come through.
3. The pyramid screen will make the fluids distribute as a much thinner layers which also helps to increase the flow rate and make the solids much dryer. And it can also separate solids around 3 meshes finer than the flat type screens.
These advantages pyramid screen will especially appear more clear when fed with larger volume drilling fluids that can submerge the screen panel. Thus the full screen effective area will be fully used.

Generally a solids control system will have all the 4 stages separation equipment for drilling cuttings and fluids. However, not all the equipment would have to be used when drilling. Hence, it will be better to design an overflow line for the drilling fluids on the mud tank to let the drilling fluids could flow bypass the equipment will not be used in some specific process.
In generally condition, the overflow line is designed as a U type slot on one side of the mud tank top. It is starting from the sand trap compartment of the mud tank to at least the suction tank where the high pressure mud pump could suck the active drilling fluids and transfer to the rig. As per customers’ requirements, this overflow line could extend to the drilling fluids mixing tank and storage tank.

drilling mud recycling system

solids control system on site layout

Shale shaker, de-sander, de-silter and decanter centrifuge are seen as the 4 stages of solids control equipment which can finally separate out the cuttings with size down to 2-5 microns. In some solids control system, there will also have vacuum degasser located between the shale shaker and cyclone units. This degasser is used to remove the entrapped gas in the drilling fluids like CO2. However, this degasser unit is not used very often.
When the time no need start this machine, we can close the gate on the overflow line to the degasser sucking compartment, and then the drilling fluids could flow directly to the de-sander compartment after treated by the shale shaker. Even, sometimes then no need the cyclone unit, the drilling fluids could flow into the centrifuge feeding compartment. This always happens at the beginning time of the drilling as there is not much cuttings in the drilling fluids.
By opening or closing the gate between the overflow line and each compartment of the mud tank. The mud engineer could guide the drilling fluids flow so than do a better control of the solids control system. You know, turn off the equipment will not be used temporally will save a lot when drilling, and that is also a protection on the machine.
Knowing how the overflow line works would be much helpful for us to design the drilling fluids solids control system. Once the system arrives at the drilling site, this could greatly help to increase the working efficiency.

One set 500GPM drilling mud recycling system was sent to Middle East for water well drilling. Besides the drilling mud recycling system for oil drilling, they also need drill water well for daily requirement for clean water. For the person living in Middle East, water is more important than oil. Sounds like a joke, but this is reality.
Water well is not so deep like the oil well, and the drilling cost is also very cheap comparing with oil drilling. However, both this 2 drilling processes need the drilling mud recycling system to speed up the drilling process and protect the drill bit. Water well drilling may not need the used drilling mud to be separated very clean as it is not requested strictly. Just like this 500GPM unit shipped to Middle East, it is a very compact
model, while it has all the necessary separation equipment.


water well drilling mud system

It has one unit shale shaker GNZS703DZ with 3 panel screens which could remove out the solids always larger than 300 microns. This model is with the mud feeder on top of the shaker deck so that this shaker could be much more compact. As the water well drilling is always not so deep, hence, the solids coming out with the drilling mud is always not so hard. In this 500GPM mud recycling system, the de-sander cone is not equipped, but directly the de-silter cone would be used to separate the solids size of around 20 microns.
This 500GPM water well drilling mud system is a standard GN model GNMS-500G with 2 unit centrifugal pumps. One of each is used as feeding pump for the de-silter cyclone, and the other one is used for mud mixing, the mud tank is divided into 2 compartments. It has enough space for clean mud storage.
Though this 500GPM mud system is for water well drilling, it can also be used in other drilling project like HDD. As the working principle is completely the same. The customer killed two birds with only one stone.