Drilling Waste Management

Many people are interested in GN Solids Control Screen Vacuum System. It is not a popular technology, many people do not know much about the vacuum screen technology. Many customers contact GN Solids Control to ask for information of Screen Vacuum Unit, including Catch Pan, Hoses and all the required accessories. Below are some communications between clients and GN Solids Control.

Question: The Screen Vacuum Unit is designed to be used on Onshore rig and offshore rigs. There are different shale shaker models at different drilling rigs. Can GN Solids Control build Catch Pans based on the existing shale Shaker models?
Reply from GN Solids Control: GN Solids Control can only build catch pan for GN own design shale shaker, and a few shale shaker models. GN Solids Control cannot make catch pan for other brand shale shaker at this moment.

Question: It said, the air pressure required is 100-150 psi. Most of the rig air compressor only supply 80-120 psi, would this affected the Screen Vacuum Unit performance?

Reply from GN Solids Control: 80-120 PSI is fine.

Question: What are the sizes of hoses from the catch pan to the Screen vacuum Unit? What are the chances of this hoses being plugged up?
Reply from GN Solids Control: It’s 2 inch hoses from the catch pan to the screen vacuum unit.
Because of the high vacuum which is up to 25 HG (Mercury Column), the power for suction is high. And also the hose for the suction is specially designed with anti-blocking material like plastic inside the hose. So it will avoid the blocking.
The capability of the vacuum pump is shown below as in the video:

Question: Where is the recovery fluid going to be discharge? Back to the active or through centrifuge?
Reply from GN Solids Control: The recovery fluid will go back to the shaker tank under the shale shaker, it needs to be treated by the afterward solids control equipment like desander desilter or decanter centrifuge. The advantage for our vacuum screen unit is that, you can calculate the flowrate of the recovery fluids volume.

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.

GN Solids Control is specialized in drilling mud solids control and waste management solutions. GN Solids Control is capable to design and make Oil Water and Solids Separation System to treat and recover various kinds of waste materials.

GN Oil Water and Solids Separation Systems are capable to treat below waste materials, but not only limited to below materials:

1. It can be used to treat oil sludge and oil, oil contaminated soil remediation, like from drilling waste pits, or from pondsand tanks
2. It can be used for water oil contaminated water-control and recovery
3. It can be used to treat waste oil and recover the oil to reuse
4. It can also be used to treat waste oil, water and solids mixture, and to recover oil, water and reduce the solids waste

Oil sludge means the waste mixture consisting of oil, water and solids. Oil water separation system is used to treat the oil sludge in order to reduce waste material, and recover oil and water for reuse. The oil sludge treatment system is also a popular solution to treat oil contaminated soil and sands.

Oil sludge is a mixture consisting of oil, water and sands. The treatment on oil sludge would recover much oil and water for reuse. Also it is an ideal solution to for the solids disposal. More oil and water recovered, more energy and resource could be saved. GN oil sludge treatment products mainly include decanter centrifuge, oil water separators and thermal desorption unit.

As many customers did not do waste management system before. To ensure GN Oil Water and Solids Separation Systems can applied for their applications, GN Solids Control specially designed a one-skid compact Oil Water and Solids Separation System for trial purpose. GN one-skid Oil Water Solids Separation System is in stock for sale. Clients can buy the small system as trial base to show to their clients their capacity to do the projects. For clients in China, they can choose to buy or rent the one-skid system.

If clients do not want to buy the one-skid compact Oil Water and Solids Separation, they can send their oil sludge or waste material to GN Solids Control. GN Solids Control can do the separation at GN factories and show clients the performance. After separation, GN Solids Control can do lab test and show the final output specs to the clients.


Last week, GN Solids Control got an inquire from a client regarding oil sludge treatment system. The client said they are a company specializing in the industrial cleaning works. They are intend to treat the sludge in oil comes from below field:

1) Waste tank bottom sludge, oily sewage generated by the crude oil tank;
2) sludge, oil sands or soil from oil pit of the refinery plant;
3) Waste oil-based drilling fluid or oil base cuttings produced by oil and gas drilling, etc.;

As part of the development of the client activity, and also they hearted about GN Solids Control before, they are interested in the acquisition of GN Solids Control Oil sludge treatment solution, for that they ask GN Solids Control to give them a suitable solution for (01) unit of sludge oil treatment plant . They want the oil sludge treatment system with capacity of 2 m3/h to 5 m3/h.

GN Solids Control confirmed with the client that, the material mentioned is their list is all inside GN Solids Control scope. Based on their requirement on handling capacity, GN Solids Control recommends the oil sludge treatment system model GNOST-05A, which can suit for the client’s capacity.

Major separation equipment in the oil sludge treatment unit is high G drying shaker, 2-phase decanter centrifuge, 3-phase disc centrifuge, dewatering unit, screw pumps slurry pump, mud agitators, etc.. .

The technology GN Solids Control is using is heating and chemical washing. The processing equipment in the system is GN core products which are sold well and performance good for many years.

GN Solids Control has many oil sludge treatment system running in China and outside China. GN Solids Control has projects reference in China, Canada, USA, Qatar, Kuwait, Kazakhstan, Indian, Indonesia, Korea, Poland, UAE, etc…
If you have any questions about sludge oil treatment, you want to get solution on sludge oil treatment, welcome you contact GN Solids Control.

Drilling cuttings solidification or stabilization unit is for the final treatment of drilling cuttings or waste sludge after the drying treatment. It is especially used to treat the drill cuttings treated by GN vertical cuttings dryer, and GN high G drying shale shaker, or decanter centrifuges.

A full package of GN Drilling Cuttings Solidification Unit is finished for production and inspected by international famous third party inspection company. The full package of GN Drilling Cuttings Solidification Unit is made for an Africa client. It will be dispatched to the sea port for exporting to the Africa client to complete his waste management processing system.

Drilling Cuttings Solidification Unit can use lime as curing agent, flyash and Cement kiln dust as filler to do the solidification. This apply to solidifying the inorganic pollutant, like Petroleum refining sludge, Heavy metal sludge, oxidizing material, waste acid etc. The curing agent and filler is easy to get; operation is easier and cheaper than cement solidification.
Drilling Cuttings Solidification Unit is composed of waste cuttings transfer system, mixing system, solidifying system, electrical control system, lighting etc. It can be used for transferring, mixing, agitating and solidifying of the waste cuttings.

GN Solidification unit is composed of Auger skip feeder unit, Single axis continuous Rotary mixer, variable speed control screw conveyor, electrical control system and ladder, walkway, handrails etc. GN Solidification unit is with compact design, reasonable layout; it is convenient for assembly & disassembly.

Besides Drilling Cuttings Solidification Unit, GN Solids Control design and makes all the full line solids control and drilling waste management equipment before the Drilling Cuttings Solidification Unit, like the solids control shale shaker, mud cleaner, desander, desilter, vacuum degasser, various decanter centrifuge, vertical cuttings dryer, high G drying shaker, various sizes and lengths screw conveyor, solids and sludge vacuum transfer pump, chemical dosing dewatering unit, oil sludge treatment system, thermal desorption unit, etc…

This week, a package of oil sludge treatment system was departed to an oil field service company in China. The unit will be used to recovery oil sludge from oil base drilling cuttings. The oil sludge treatment system including below items:
1) 2 phase decanter centrifuge. Material fed to 2 phase decanter centrifuge must be with solids content Less 20% and Particle Size less than 20mm.
2) 3 phase disc centrifuge. The solid phase material entering the three phase disc separator usually shall be reduced the solid content to less than 3% and the solid particles to less than 400 micrometers by the decanter centrifuge, then the three-phase disc separator can achieve the best effect.

3) Transfer pumps
4) Dewatering chemical dosing system with dosing pumps and automatic control system
5) Transfer tank and holding tanks for mud recovery and mud transfer.

The project is for processing oil and solid wastes in sludge storage tanks. After the oily sludge wastes have been pre-treated. After the oil sludge wastes have been treated by sieving, sand washing, demulsify, and finely screened, they have now achieved reductions and preliminary separation. After that, the oily sludge will be treated for three-phase separation.

Two phase decanter centrifuge and three phase disc centrifuge is used in the three phase separation process. After three phase centrifuge separation, the final outputs are soil, oil and water.

Chemical dosing system is used before 2 phase and 3 phase centrifuge separation to help for the removal of as more fine solids as possible.

Besides 2 phase decanter centrifuge, 3 phase disc centrifuge and chemical dosing sytem, GN Solids Control also offers other oil sludge treatment and transfer equipment, like 3 phase decanter centrifuge, high G drying shale shaker, mud cleaner, Vertical cuttings dryer, Drilling Cuttings Solidification Unit, Thermal Desorption Unit (TDU), oil water separator, sludge vacuum pump, screw conveyor, etc…

Recently, GN Solid Control has completed the design and manufacture of a set of oil sludge treatment system for an oil field environmental protection company in China. Since the oil sludge treatment system was launched on the market, it has been widely concerned by customers no matter in China or outside of China, and the feedback from the on-site operation of the market is good. More and more oil field environmental protection contractors inquire and order the system as an important solution to reduce the content of harmful substances in oil sludge efficiently and economically.

The oil sludge treatment system has two separation principles: chemical dosing and physical separation after heating. GN oil sludge separation system is composed of several modules with different functions to gradually recover water and oil from the sludge. The following is a brief introduction of the system:

1) Sludge vacuum transfer pump module – the sludge from oil-based mud drilling cuttings has high viscosity and high sludge content, which requires a powerful and efficient conveying device to suck the sludge out of the mud pit and feed to the oil sludge treatment system. GN sludge vacuum pump is a fully pneumatic pump with no electrical components and does not produce any sparks in use. it is especially suitable for oil and gas explosion-proof environment. With 85Kpa vacuum, the viscous sludge can be sucked and discharged to other place far away.

2) Pre-mixing module – before the sludge is fed into the separation module, the material needs to be homogeneously mixed to more than 80% of the liquid content. At the same time, in order to enhance the separation effect of oil and mud, it is necessary to add chemicals in the process of homogeneous mixing.

3) Separation module – GN Solid Control uses different separation equipment to separate oil and water from the sludge step by step. High G force shale shaker, 2-phase decanter centrifuge and 3-phase disc centrifuge are used in the Separation module.

Solids and sludge vacuum pump is a popular feeding pump for GN oily sludge treatment system.

GN Solids Control makes different sizes vacuum pump for drill cuttings, solids and sludge transfer. GN vacuum pumps are 100% driven by air, without electrical parts. The pumps can be used for hazardous areas for zone 1 and zone 2 applications. And there are no rotating parts on the pump. It makes the vacuum sludge and solids transfer pump is easy for operation and maintenance.

So many clients are wondering will the air compressor included in GN Solids Control supply scope? How they can get the air source? The vacuum sludge and solids transfer pump can be fed air from other air suppliers, like from the rigs, or supplied with a separate air compressor.
From GN Solids Control proposal, the air compressor is excluded. If clients want the specification of the air compressor, they can contact GN sales team to ask for recommendations.

But as GN Solids Control is not the manufacturer for air compressor. GN Solids Control will suggest the clients to contact air compressor suppliers directly and buy the air compressor by themselves.

Besides the air compressor, clients will also need a heating system for the oily sludge treatment system to heat up the sludge to 70 C degrees? The heating system can be Electrical or by a heat exchanger. Clients can use the hot water boiler to heat up by steam, or they can use hot oil boilers. GN Solids Control already equip the heating lines inside the tank of the oil sludge treatment system, clients can feed it with hot steam or hot oil. The volume of the hot heat depends on the ambient temperature. Clients will need to offer the minimum Ambient temperature for their operation to calculate the size of the boiler for them. Water treatment unit is excluded in GN supply scope of the standard oily sludge treatment system.

Recently, a client ask GN questions about the operation of the big size GN Sludge and solids vacuum transfer pump GNSP40B. The client want to know what is the flow rate of the air supply to GN Sludge and solids vacuum pump? No indication of airflow, clients are just looking at the outlet pressure on the main compressor display to increase the air supply flow rate above 20M3/min will make the pump more powerful.

Below is the communications between GN Solids Control and the client.
The client has been testing the vacuum pump to remove soft sand , and noticed the following situation:
1) Suction pressure is reduced when the status turns into loading (On Auto mode )
2) Continues airflow from the discharge while it is sucking.
3) When the section line is extended to 40 m, the efficiency dramatically reduced.
The client want GN Solids Control could clarify the above.

GN Solids Control replied that,
1) It is right that the air flow goes out from the discharge hose while suction. So this moving air will produce high vacuum by the jet pack. That’s the working principle.
2) The minimum requirement for air supply to feed to the 40 pump is 17M3/hour with pressure 0.8 – 0.9 mpa. What is your air supply now? Clients replied that the pressure while sucking is 0.5 mpa and while unloading increase to 0.8 mpa…. Please advise how to increase the supply pressure while sucking?

GN Solids Control asked the client: Do you have an air storage tank between the air compressor and the pump? And what’s the volume of the Air tank? Clients replied that, there is no air storage tank available, the air is going direct to the pump
GN Solids Control expressed that; it will improve the pump performance a lot
to have air flow rate above 20m3/min Minimum needs to be 17m3/min
Also you need to have an air tank to work as buffer tank to connect to the pump.
By doing above you can make the pump working more properly.
3) 40 meters for water is fine but for solids suction is too long. It’s better to keep less than 12 meters. But as the discharge pressure is high. GN Solids Control suggests the client to reduce the suction hose to less than 12m, but they can have much longer hose for discharge.
4) The longer of suction hose, the longer of the suction time should be set. While leaving factory. GN Solids Control sets 10 Seconds for suction and 10 seconds for discharge. Clients can adjust the suction and discharging time according to job site situation.

Vertical cuttings dryer is a major separation machine for oil base mud drilling cuttings treatment. The VG dryer is used to further treat and recover drilling cuttings discharged from shale shaker, and in some cases, the cuttings from mud cleaner. The Vertical cuttings dryer cannot be used to treat drilling cuttings discharged from decanter centrifuge. As the solids discharged from decanter centrifuge is something like soil. The vertical cuttings dryer is equipped with screen basket with bigger opening like 0.25mm, 0.35mm and 0.5 mm. The centrifuge discharge is too fine. They will all pass the VG dryer screen basket. There are nothing can be recovered.

The control panel of the vertical cutting dryer must have connection between the main drive motor and the oil pump. So that when the main drive motor is turned on before the oil pump, it cannot be started. If there were not connections between the main drive motor and the oil pump, the VG dryer main motor can be started before or after the oil pump running, there may be no lubrication oil for cooling down while the main drive motor is running. It will make damage to the vertical cuttings dryer. The situation must be taken into consideration because this situation may be lead to damage the bearing or rotor due to Stopped or failure oil pump or leakage or drop of oil pressure .

These situation is abnormal, because according to the operating procedures must be start on the oil pump in the first until the oil pressure reaches 15-25 psi, after 5 minutes of running the oil pump go to start on the main drive to ensure that oil reached to all rotating parts , bearing .

Where is supposed if happened any drop in oil pressure or failure in oil pump the main drive shut off before happens any failure in bearing or rotor. ( for protection the unit)