Sep 06

We discussed about dark colored centrate.

In the optimization of decanter centrifuges, there are other considerations.

  1. Gray, forming centrate
  • Sometimes the discharged centrate carries gray color, and sometime with foams on it. Dosage of flocculants needs to be adjusted according to accommodate the changing solids concentration
  • Optimization of liquid ring. When decanter centrifuge is in operation, there is a liquid ring on the wall of rotating bowl. A thin liquid ring means dryer solids
  • The strength of flocculants. When flocculants comes into rotating bowl, its relative speed to solids rotating together with the bowl is the rotating speed of bowl, which can be a big number. The flocculants needs to be accelerated to this speed. In order to accelerate, flocculants particles will be exerted a strong shearing force. The flocculants needs to be strong enough to withstand the huge force and will not collapse. Some companies have developed some kinds of strong flocculants;
  1. Low dryness

Solids dryness depends on many factors. Below is a summary of the impact of different parameters on the dryness of solids

  • If feed flow rate is lowered, solids dryness increases;
  • If flocculants flow rate increases, solids dryness increases;
  • If auger torque increases, solids dryness increases;
  • If differential speed decreases, solids dryness increases;

Factors impacting solids concentration of discharged liquid:

  • If feed flow rate increases, solids concentration in liquid increases;
  • If flocculants dosage decreases, solids concentration in liquid increases;
  • If auger torque increases, solids concentration in liquid increases;
  • If differential speed decreases, solids concentration in liquid decreases.

It can be seen that it is impossible to optimize the performance of decanter centrifuge without some kind of automation. And all the influencing factors needs to be taken into the algorithm to make performance optimization. Field optimization is much more complex than what we can see on paper.



written by Decanter Centrifuge

Aug 16

Decanter centrifuge is a very important processing tool in a wide scope of liquid/solid separation situations. The solid-bowl scroll-discharge centrifuge (which is usually called decanter centrifuge) is the workhorse of a wide range of liquid/solid separation activities in different industry sectors including mining, oil & gas, vinery, wine, chemical industry, etc.. In environmental protection decanter centrifuge can effectively perform dewatering of waste sludge, an important application of decanter centrifuge. Because of this application decanter centrifuge is recognized well and is considered an indispensable piece of equipment in the industry. GN Solids Control manufactures full series of decanter centrifuges, from 9” to 30”, to meet the needs of different application of many industrial applications.

In theory decanter centrifuge is a relatively simple machine. However in the manufacturing process it is far more complex than it is thought. Usually the rotating assembly contains a bowl rotating at very high speed (sometimes as high as 10K RPM) with an auger (or also called screw conveyor). Slurry is pumped into the rotating assembly by a pump through a feeding tube, clarified liquid decants out from one end of the rotating bowl and the separated solids is moved to the other end of the rotating bowl and discharged out from exiting opening. The biggest advantage of decanter centrifuge is its ability to separate high concentration of solids from liquid at pretty high throughput speed, with small liquid left in the separated solids. Decanter centrifuge can handle very high solids concentration, sometimes as high as 80% of liquid volume. Decanter centrifuges made by GN Solids Control work effective well. Solids discharged from GN Decenter centrifuge contains very small amount of water that the solids can be stacked without much seepage from the solids. However there is a lot of consideration to be made for the decanter centrifuge to perform properly and there are a lot of variables to consider when designing one system.18-inch-decanter-centrifuge


written by Decanter Centrifuge

Jul 26

GN Dewatering System Sold to Canada, customer use for slurry waste solutions. Slurry Categories as follow 1. Directly drilling soil from non- contaminated job sites 2. Hydro slurry from non-contaminated Hydro excavation requires less labor than conventional digging methods. After vacuum and roll off truck finished, GN the Dewatering system will be perfect solution for it.

The Dewatering System included

  1. Feeding hopper with High G shale Shaker model number GNZKR-1230 capacity 10-150t/h Storage tank size 3800 x 2200 x 1512 mm with 2 agitators both 5.5kWand 2 Slurry pump one is 22kW another is 5.5kW both pump control by the VFD system.
  2. HDD CBM Shaker tank

GN Double Deck Finder Shaker model number GNZS706 E with 140 m3/h (616GPM) capacity 6 pcs screen with adjust angle -1~ +5 degree. And GN desilter model number GNZJ594E-12N 120m3/h (528GPM) capacity 3 pcs screen with adjust angle -1~ +5 degree. One Slurry pump with a 22kW motor with Shaker and desilter tank size 10369 x 2100 x 2312 mm. 2 agitators with 11kW.

  1. Decanter Centrifuge

GN GNLW553C-VFD 22 inches (550mm) decanter centrifuge, capacity with 90 m3/h (400 GPM) support   with screw pump GNG60A-150 15kW capacity 60m3/h. Centrifuge skid not only supports the centrifuge but also can adjust the height. Under the centrifuge come with storage tank and transfer pump model number GNSB3X2B -7.5J flow rate at 30m3/h (132 GPM) motor power with 7.5kW, the speed with 1450 rpm

  1. Dose Machine

This comes with 3 compartments with 3 set agitator can automatic powder chemical dosing. Capacity 2000L/Hour, Tank Volume 2000L, Hopper Volume 45L

For more information please contact GN sales representative at Web:

Add: 6710 Windfern Rd, Houston, TX 77040



written by Decanter Centrifuge

Jul 12

Decanter centrifuge is widely used in industry to separation solids from liquid at fast speed. Without decanter centrifuge industrial process will be way slowed down.

There are many factors affecting the operation of decanter centrifuge, many people think it mysterious while others think decanter centrifuge a common equipment and there is nothing weird.

First is the centrifugal force, which is usually defined as times the centrifugal force than regular gravity. The parameter depends on the diameter of rotating bowl of decanter centrifuge, and the rotating speed. Centrifugal force is more sensitive to bow diameter than rotation speed as G force is proportional to the square of bow diameter.

With higher G force, settlement time for solids is reduced to seconds instead of a few hours with gravity settlement.

Another consideration is the separation speed. This is proportional to the gravity difference between solids and liquid. The smaller the difference, the slower the settlement. If gravity difference between solids and liquid is trivial, separation will take extended long time.

Particle size also affect separation speed. For bigger particles, it is easy for them to deposit because buoyancy can be neglected for bigger particles. However as particle sizes become smaller, buoyance becomes important, and in the extreme condition, buoyance can balance out gravity force and small particle will float in the liquid and never come to bow wall.

Differential speed between scroll and rotating bowl is another important consideration for separation. This differential speed must be optimized to minimize case thickness as it will affect discharge quality. Higher differential speed results in good throughput speed but less clear liquid. Solids settlement becomes even more complex when there is both big particles and small particles, with different gravity.

Above is a few factors contributing to the clarity of liquid. There are other factors impacting performance of decanter centrifuge. Designers need to prioritize these factors to make the equipment tailored to specific application.decanter-centrifuge


written by Decanter Centrifuge

Jun 13

GN Solids Control is strong brand for the manufacturing of decanter centrifuge in China.

Decanter centrifuge decants solids continuously from liquid by a auger inside the rotating bowl to flow out from solids discharge holes. It is widely used in different industry sectors for separation purposes.

Decenter centrifuge comprises of rotating bowl, auger rotating at differential speed and gear box. Some model use variable frequency controllers to control the speed of both the bowl and the auger, to control their absolute rotation speed, and to control the differential speed between the bowl and the auger.

Its working principle. Once slurry comes into the rotation bowl, it will be facing the intense centrifugal force generated by the rotation of the bowl. Usually solids are heavier than liquid and stronger centrifugal force is applied to solids, and thus pushing them toward the wall of the bowl, and the lighter phase (liquid) is under less centrifugal force and thus it “floats” on top of the settled solids, forming a liquid layer. As there is a differential speed between the rotating bowl, and the rotating auger, deposited solids will be pushed towards slowly towards cone side of rotating bowl, continuously flow out from discharging port.

GN Solids control has long history to manufacture decanter centrifuge and its decanter centrifuge is used in ten of countries playing an important role in solids control of oil and gas drilling process.

In the oil and gas drilling process, there is a big challenge for decanter centrifuge as the concentration of solids changes tremendously. And the existence of hard particles generates serious wear on equipment. Also drilling mud go through different solids control equipment. These equipment perform in very different ways, making the situation very complex. It is extremely difficult to maintain decanter centrifuge in overall optimized performance.

In order to handle these challenges, GN Solids Control performed sound research and development work, and invested a good sum of money into it. The result is a series of decanter centrifuge with outstanding performance.

  1. GN uses duplex stainless steel, which is much stronger than regular 316 stainless steel. This allows GN Solids Control to manufacturing decanter centrifuge with much higher rotation speed and thus much higher separation coefficient. The other advantage of duplex stainless steel is strong resistance to wear, making decanter centrifuge by GN Solids Control last much longer than those made of regular 316 stainless steel;
  2. Technique employed to manufacture the bowl. GN Solids Control uses centrifugal casting technique to make the bowl of decanter centrifuge. This technique generate a much uniform distribution of stainless steel mass and a much reduced challenges in balance the bowl, and the balancing of whole system;
  3. GN Solids Control extends speed range of bowl balancing to both the bowl & auger themselves. GN performs low speed balancing, medium speed balancing and high speed balance for both of them to ensure these two critical rotating parts are well balanced throughout the speed spectrum. And this whole speed balancing is also performed on the rotating assembly. This allows smooth and quiet operation of decanter centrifuge by GN Solids Control;
  4. GN Solids Control also use tungsten carbide to enhance the life of all parts prone to wear, including solids discharge port, auger blades, end of auger, and any parts that are exposed to strong solids flow. All these significantly extend the life of GN decanter centriguge;
  5. GN solids control also performed in-depth R&D work and developed a control system which control the operation of decanter centrifuge. It uses advance algorithm to predict the performance of decanter centrifuge and adjust system operation parameters in a timely manner, this greatly enhance equipment performance and reduced down time.


Field application shows that with the support of all the above mentioned technology, decanter centrifuge by GN Solids Control outperforms decanter centrifuge  by famous manufacturer, which is a few times more expensive than GN decanter centrifuge.

GN is the right name for you to choose in solids/liquid separation challenges.22-inch-decanter-centrifuge


written by Decanter Centrifuge

Apr 12

In March 2019 GN Solids Control releases its new generation of inclined plate clarifier(IPC).

Liquid/solid separator is an indispensable equipment in all situation where segregation of solids from liquid is required.

The working principle of inclined plate separator is simple.  It is the same as setting solids containing liquid in a container. However, the speed of such setting process is quite slow. We need to find some way to expedite this process. Also there needs to be some mechanism to remove the deposited solids from the container without human interface as it is pretty difficult to remove solids from such container.

GN Solids Control has been making continuous effort to improve its inclined plate clarifier, in terms of efficiency and ease of operation. The inclined plate clarifier is the 5th generation of this equipment and it is much better than previous versions.

  1. High separation efficiency. When sludge comes into the IPC, its speed is reduced very rapidly by a mechanism and flow gently to inclined plate array, where the flow speed is reduced further, with solids quickly depositing on the inclined plates. Optimized angle and location of the inclined plate effectively increase the separation speed;
  2. Quick removal of deposit solids. With the building up on the inclined plate, the solids will move toward hopper at the bottom of the IPC, where an auger will move the solids to the suction point. The suction pump will send the solids to the skip outside. This eliminate any manual removal of solids;
  3. Special designed hopper acting as an accumulator is part of the IPC and collects the solids and make efficient solids removal possible.
  4. The inclined plate array can be easily removed and cleaned and put back. This greatly help IPC cleaning;
  5. The shape of the IPC is gradually evaluated to the current shape, which minimized the volume of the IPC to further assist liquid/water separation and can be used in conjunction with a buffer tank of complementary shape to make a compact tank cleaning system, where the volume of buffer tanks is expected to be maximized.

For more information please visit

drilling mud system


written by Decanter Centrifuge

Mar 22

In February 2019, GN Solids Control began the manufacturing of its first automatic mud tank cleaning system for a customer in America, a significant moment for China manufacturer of solids control equipment in oil and gas drilling.

Mud tanks cleaning has been a tedious and labor intensive work. Whenever a drilling rig changes to a new kind of mud, or there is too much deposition of expensive barite on the bottom of mud tank, cleaning work has to be performed. Workers with heavy equipment need to come into the refined space of a mud tank to clean mud residuals with high pressure chemical solution spray, exposing themselves to the dangerous environment.

GN Solids Control’s automatic tank cleaning system can bring this high risky high cost work to an end.

Using its mature sub systems, GN Solids Control’s automatic tank cleaning system can automatically finish mud tank cleaning work.

Chemical solution is prepared in the dosing tank with dosing pump. An automatic mixer will add chemical solution automatically to the buffer tank.

Buffer tank provides chemical solutions to booster pump, which pressurizes the solution and send it to automatic tank cleaner.

Automatic tank cleaner scans the inside of mud tank at preset scanning patter, hitting each and every spot of mud tank inner shell to kick out mud contaminant. It takes about 15 minutes to finish a complete scanning cycle.

A powerful suction pump will collect dirty solution, including deposited barite, from the bottom of mud tank, and transfer it to clarifier.

Specially designed clarifier set the solids in the liquid very quickly. While solids accumulated at the special shaped bottom of clarifier being pumped out by a membrane pump, clear solution on top of the clarifier will overflow to the buffer tank, being ready for the next cleaning cycle.

Automatic tank cleaning system by GN Solids Control features:

  • High efficiency. A mud tank can be cleaned in a matte of hours
  • Fully automatic: no operator interference is necessary
  • Much less risky: human entrance into dangerous environment is minimized;
  • Much less costly: only one operator is needed and human cost is cut tremendously.



written by Decanter Centrifuge

Mar 08

In the past few years, drilling waste disposal has received increasing attention from the waste management industry. But most of the customers in this field are basically related to the oil and gas industry. The cuttings removed from the primary screening of vibrating screens and other solid-control equipment need to be recycled to the utmost extent. The crude oil tank bottom sediments of petroleum refining and chemical enterprises and the oily sludge in refinery wastewater also need to be collected and transported.

So far, GN Solid Control has been able to provide a complete treatment solution for solid control equipment and almost all waste management equipment. However, these are not enough. The entire treatment plan also requires a transfer device to be connected between the two devices or an oily sludge transfer from the sludge pit to the waste management equipment. GN  sludge vacuum pump is undoubtedly the ideal choice for this work.

GN’s vacuum pump is used for conveying environment with high solid content, high viscosity and high load, and has the characteristics of high conveying capacity, easy operation and easy maintenance. The maximum solid content of the transport medium is as high as 80%. This pump is an all air operated pump. Connected to an air compressor to achieve a 25 foot mercury vacuum. It has long-distance water absorption and drainage capacity of 50 meters and 1000 meters respectively. The air works to ensure that it is suitable for use in hazardous areas to the first zone. It is a truly high security grading device.

In addition to drilling cuttings and sludge transport, the vacuum pump can also be used for sludge cleaning, barge storage and bottom cleaning, and even dry and coarse material handling.

Welcome to and send your questions to



written by Decanter Centrifuge

Jan 25

In the oil and gas drilling, mud tanks need regular cleaning for many reasons. Some of them are:

  1. Using the mud tank for mud of different properties
  2. Making the mud tank ready for new drilling tasks
  3. Getting rid of the deposit on tank bottom
  4. Maintaining the effective volume of mud tanks
  5. Increasing tank efficiency

Most of the tank cleaning job is done manually. Workers needs to get into the restricted space to clean the mud tank using high pressure spray. This is a tedious and dangerous process as the workers have very limited movement in a limited space, where temperature is usually extreme, no air circulation, existence of dangerous gas (inflammable, explosive, corrosive, etc.), exposing the worker to a very dangerous and labor demanding environment, a big challenge to HSE regulation practioners.

Automatic tank cleaning systems will effectively eliminate the problems for such job.

In general such system will have a cleaning machine positions in the mud tank, which connects with high pressure chemical solutions dosed for the particular cleaning job (usually surfactant). The cleaning machine will spray high pressure solution in a special cleaning pattern, so that the mud tanks can be cleaned properly.

Centrifugal pumps will send pressurized chemical solution to the cleaning machine located in the mud tank. The cleaning machine will apply high pressurized solution to the tank surface to “rush” mud residual out. Vacuum pump transfers the sludge to the post processing equipment such as desilter, and inclined plate clarifier, to separate the solids. The solutions will be transferred back to buffer tank and be reused, forming a closed loop cleaning system.

The advantages of such system are:

  1. Greatly increase cleaning efficiency, usually four hour is required to clean one tank around 6,000m3
  2. Usually a 30-40% reduction of confined entry to mud tank;
  3. And 1/3 less of waste solids generated

GN Solids Control manufactures GNTC-30B closed loop automatic cleaning system. In addition to the above features, this system also carries the following advantages:

  • The whole system is integrated into a compact package, with everything included in it;
  • Mature: major sub-systems such as inclined plate clarifier, centrifugal pumps, vacuum pumps are from GN Solids Control, demonstrating reliable outstanding performance;
  • Flexible: this system can be configured with many other features. It can be customized with the addition of agitator for the addition of chemical to accommodate needs for the cleaning of different muds (water based, oil based, etc.), heating systems for the extreme weather conditions, and so on;
  • The complete package can be loaded on a truck (temporary or permanently) to perform mud cleaning jobs in different locations, which can greatly improve the profitability of the service provider using such system;
  • Automation options available. Automation packages can be added to the system to achieve advanced cleaning capabilities including closed loop pressure control, customized recipes for different tank sizes and shapes, and a more precisely defined scanning & cleaning pattern.


  1. Mud tank
  2. Tank cleaning head
  3. Strainer
  4. Vacuum pump
  5. Desilter
  6. Clarifier
  7. Air pump
  8. Buffer tank
  9. Skip
  10. Centrifugal pump

written by Decanter Centrifuge

Dec 27

Recently, the containerized oily sludge treatment system sold by Guanneng to European customers has been installed and commissioned and ready for shipment to Europe. The containerized oily sludge treatment system is in response to European customer requirements. The company can be combined with oil sludge treatment. The system has many years of experience in custom-made containerized system. In the manufacture of oily sludge treatment system equipment, Guanneng’s production department adopts the industry-leading pickling, passivation, hot-dip galvanizing process and high-pressure airless spraying. The construction of the equipment has greatly improved the wear-resisting and anti-corrosion effect of the surface of the product itself, and has been highly recognized by European customers.
The containerized oily sludge treatment system produced by GN Solids Control is customized according to customer needs. This system is mainly composed of oily sludge vacuum pump, premixed tank, vibrating screening system, centrifuge separation system, dosing flocculation system, oil-water separation. System, oil tank, water tank, container, etc., oily sludge contains a large amount of oily benzene, phenols, strontium, barium and other odorous toxic substances. GN Solids Control uses centrifugal separation to transport oily sludge through a centrifuge. The solid-liquid two-phase separation is carried out, and the separated liquid phase is an oil-water mixture. The oil-water mixture is then transferred to a three-phase disc machine for oil-water separation. European customers have defined the relevant parameters in the previous process of dewatering of oily sludge, the temperature of oily sludge, the amount of breaker and flocculant used, which is more conducive to the technical system of containerized oily sludge treatment system. Process design.

Welcome to and send your questions to

Solidification Unit


written by Decanter Centrifuge