Tag Archives: Drilling Fluid Centrifuge

Centrifuge used in well drilling mud solids control is decanter centrifuge, also referred as decanting centrifuge. It is rather popular with drilling contractors or fluids service company. Strictly speaking, centrifuge is the 5th purification or cleaning equipment for drilling fluid. It is set after desilter cone or mud cleaner. It is mainly used to separate solids sized 2~7 microns.

decanters

Description of decanter centrifuge

Decanter centrifuge including low speed, middle speed and high speed one. Different speed will produce different centrifugal force, treating capacity, and separation point. Centrifuge consists of scroll conveyor, drum, motor, differential, inlet port, discharge port, solid discard port, and so on. Decanter centrifuge will be fed by submersible slurry pump or screw pump with drilling fluid for finer separation of solid.

centrifuge

Centrifuge procedure

The material feeding into the inlet port, under centrifugal force generated by drum and scroll conveyor rotation, the solid will be dried and discharged via solids discard port. We know, on the centrifuge bowl or drum there are liquid zone and drying zone. Cleaned drilling fluids will flow out centrifuge via the clean liquid effluent at liquid zone end.

If you are looking for an oilfield decanter centrifuge that is highly effective and affordable, please browse our products. We offer a range of centrifuges of different sizes and capabilities that give you the exact results you need at a price that you can afford.

High speed has costs, not to the driller, but to the centrifuge owner. Suppose the centrifuge is one pound out of balance. If the centrifuge rotates at 900 RPM, the unbalanced load is 276 lbs, and this unbalanced load is carried by the bearings through to the frame. If it sped up too 1800 RPM, the unbalance load goes up to 1,104 lbs. To keep the centrifuge from shaking itself to death or an early bearing failure, higher speeds require better mechanical tolerances. Generally, to maintain these tolerances over a service life of many years, the centrifuge should be made from stainless steel.

decanter centrifuge

The second problem is stress. All of the mud in the centrifuge is pressing outward putting the bowl and hubs under stress. As the centrifuge is run faster and faster, the stresses build up and can cause catastrophic failure. No decanter centrifuge should be run faster, with a heavier weight mud than it’s designer planned on, and in addition, the structural parts should be in good shape. Corrosion and wear can weaken a centrifuge to the point where it is unsafe at any useful speed. Higher speeds require high strength, corrosion resistant materials.

centrifuge

The third problem is wear. Drilling mud contains grit; it slowly grinds the wearing surfaces of the centrifuge, and eventually enough metal is worn away that the centrifuge must be rebuilt. The wear rate is proportional to the g-force. At low speeds, the grit is ground into the metal at a moderate force, but doubling the bowl speed causes four times the wear rate. It cuts the service life to 1/4 of what it would be, and considering down time, easily increases the maintenance cost five fold.

In addition, as the centrifuge wears, it loses metal. It unfortunately doesn’t lose it uniformly, and as it wears, it goes out of balance. As I discussed previously, imbalance means premature failure through excessive vibration.

In order to fully understand how a decanter centrifuge operates, we must first define what a centrifuge does. In many industrial jobs, solid material often mixes with liquids, contaminating water supplies or turning mud into sludge.

centrifuges

A decanter centrifuge is useful in that it separates solids and liquids, and has become an essential component of water waste facilities and the chemical, oil, and food processing industries. Moreover, without a centrifuge, many of these companies would become so inefficient they could not function.

 

1) Inlet zone

The inlet zone accelerates the feed slurry up to the speed of the bowl. A properly engineered inlet zone keeps any degradation of the feed solids to a minimum as well as avoiding disturbance of the sediment in the bowl. A number of feed zone specifications are available for decanter centrifuges, each designed to ensure maximum performance in conjunction with a specific process.

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2) Screw conveyor

The key to good decanter performance lies in the efficient, effective scrolling of the sedimented solids. The design of the screw conveyor is therefore crucial. You must have the expertise needed to match the demands involved in specific industrial processes with specific configurations of flight pitch, lead angle and differential speed, in order to secure the best possible results.

3) Solids Discharge Section

Depending on the application, the consistency of the separated solids can vary from a dry powder to a paste. The configuration of the discharge zone is therefore chosen to enable such “cakes” to exit as effectively as possible. Innovative designs enables erosion-prone components used in the solids discharge zone to be replaced on site at low cost and with a minimum of disturbance to production.

4) Liquid Discharge Section

In a two-phase decanter, the liquid level is regulated by dam plates. In a three-phase centrifuge when operating in a three-phase mode, each phase discharges over a set of dam plates into separate baffled compartments in the casing.

Centrifuges are used to process unweighted and weighted, water-based and oil-base drilling fluids. The DCGLW series centrifuge uses high G-forces to separate fine solids from liquids.

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The DCGLW series is able to exert up to 2,870 G’s on the mud. It has a fixed drive unit and has customized hardware and software packages that can be designed to meet specific installation and operation needs. With a processing capacity up to 200 gal/min the DCGLW series centrifuge offers outstanding performance over a widerange of drilling applications and conditions.

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Decanters centrifuge are equipped with either fixed or variable back drive. The scrolling speed -(relative conveyor speed) can be changed in a matter of seconds by operations of a simple control switch. The optimum scowling speed is selected in each case according to solids load, required separation efficiency and required underflow density.

DC solids control based in China manufacture and supply complete line of high-speed, variable-speed and fully variable-speed drilling mud decanting centrifuge for handling drilling fluids.

The decanter centrifuge has been widely applied in drilling fluids solids control system. Due to the high rotation speed provided by decanter centrifuge, if any abnormal situation happend in use, stop running and check for solution immediately.

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Solutions to common problems of decanter centrifuge:

Problem 1: excessive vibration of decanter centrifuge.

Reasons and solutions:

1. The solids particles settled in bowl have not been cleaned thoroughly–clean it.

2. Defective shock absorber–change it for new one.

Problem 2: overtemperature of bearings. (above 75℃)

Reasons and solutions:

1. Lack of lubricating oil–oiling the bearings.

2. Wear of bearings–change the damaged bearings.

Problem 3: the bowl doesn’t work when the main motor is activated.

Reasons and solutions:

Main motor overload for excessive solids particles set in–clean the bowl and adjust the grout intake.

Problem 4: abnormal noise is heard from bowl.

Reasons and solutions:

1. unsuitable usage of lubricating oil, such as improper oil type or volume–check and adopt suitable oil.

2. bearings damaged–change for new ones.

The professional treatment of drilling fluids is essential to guarantee the perfect drilling process while simultaneously adhering to the mandatory environmental protection requirements. DC Solid control company supports this process by using high-performance centrifuges in which a robust, flexible and user-friendly design is of the utmost importance.

decanter centrifuge

Continuous treatment of the drilling fluids with DCLW centrifuges ensures that the process sequences are smooth. Our centrifuges reliably separate unwanted solid materials, thus ensuring that no contaminated fluids pollute the ground and sea water, and that drilling fluids can be reused on a permanent basis.

drilling fluid centrifuge

DCLW centrifuges can also recover the relatively expensive heavy mineral, barite, which is added to increase the weight and density of the drilling fluids. Our centrifuges are so flexible that they can be used to both, to purify the drilling mud and to recover the barite.

If you want to choose more models decanter centrifuges, please contact us. We can assist you to get more infor about it.

Decanter Centrifuges are popular solid-and-liquid separators used in multiple industries for a wide array of products. Decanters are used for the extraction of liquids from large proportions of solids. It makes use of medium-low speed suspension to process larger capacities of solids as compared to a Basket Centrifuge.

decanter centrifuge

A typical example of this type of two-phase separation is the dewatering of sludge from municipal sewage plant or industrial waste water treatment.last week, DC Machinery shipped a set of decanter centrifuge for India wasterwater procesed factory. Th model of the centrifuge is DCLW350-1200 and treating capacity is 15m3/h. With high speed and frequency conversion.

In this case, the residual moisture in the dewatered solids determines the disposal costs and the centrate quality determines the pollution load returned back to the treatment facility. Minimizing both must be achieved at the lowest possible cost, with the lowest possible polymer and energy consumption, with low maintenance costs and with the lowest possible number of required operating staff.

The decanter centrifuge consists of a solid bowl, which rotates and contains the process. A screw conveyor, contained within the bowl, turns at a slightly different speed from the bowl. If you have interest with it, please feel free to contact DC solid control.

In order to fully understand how a decanter centrifuge operates, we must first define what a centrifuge does. In many industrial jobs, solid material often mixes with liquids, contaminating water supplies or turning mud into sludge.

A decanter centrifuge is useful in that it separates solids and liquids, and has become an essential component of water waste facilities and the chemical, oil, and food processing industries. Moreover, without a centrifuge, many of these companies would become so inefficient they could not function.

Decanter centrifuges

The principle behind a decanter centrifuge is based on the theory of gravitational separation. For example, if you fill a glass with a mixture of mud and water, over time the weight of the mud will cause it to settle down at the base of the glass. With the mud congealed at the bottom, the water will be forced upwards, creating a clear separation between the two.

The ability to purify a liquid makes decanter centrifuges ideal for waste water treatment facilities. However, there are variety of industries for which such centrifuges play an important role.

Drilling mud decanter centrifuge is the fourth stage equipments for a drilling mud system.Drilling mud cleaning first stage uses drilling fluids shale shaker ,then second stage uses desander,third desilter,(now drilling mud cleaner is widely used to replace desander,desilter.

decanter centrifuge

With a horizontal oilfield decanter centrifuge, the mixture of drilling liquid and cuttings and solids enter into the centrifuge. When it enters the centrifuge, it gets spun at an extremely high rate, sometimes as much as 3000 times the force of gravity. When this happens, the solids will separate from the liquids. When they are separated, the drilling liquid can be decanted and eventually returned to the mud tank where it can be replaced into the borehole for efficient drilling.

One of the biggest advantages to having an oilfield decanter centrifuge is the size that it takes up. Compared to other solids control equipment, a centrifuge takes up less real estate.

On many oilfields the site footprint is not large enough to support a wide range of solids control equipment. A centrifuge is highly effective and efficient so you can separate solids from drilling liquids even on small drilling sites.

The three phase decanter centrifuge. It is made of cone drum, spiral unloader, differential system, bearing base, engineer base, main motor, back motor and electrical system.

centrifuge

To be as a leader of wasterwater treatment company.  DC Solid control developed a 3 phase decanter centrifuge used in oil and gas field and all kinds industires wastewater treatment projects.

three phase centrifuge

All of our decanter centrifuges adopt the international advanced special structure design. The centrifuge has the advantages of superior quality and efficiency, with larger treating capacity , better separation effect and easy to operate.

The machine has the certificated of ISO9001-2000. Meachanical properties is higher than JB/T502-2004《spiral sedimentation unload centrifuge》standard.