Mar 27

The thickness of the liquid-ring layer is an important parameter for the optimization of decanter centrifuge , which directly affects the effective settling volume of the decanter centrifuge and the length of the drying area (shore area), and then affects the sludge dewatering treatment effect. Generally, it is realized by manually adjusting the height of the liquid level baffle in the stop state. When adjusting, the height of each liquid level baffle must be consistent, otherwise it will cause severe vibration during the operation of the decanter centrifuge, and some foreign manufacturers’ products can realize automatic adjustment of liquid-ring layer thickness.


By increasing the thickness of the liquid-ring layer will increase the sedimentation area, and the residence time of the material in the decanter centrifuge will increase accordingly. The quality of the filtrate will be improved as well. On the contrary, by lowering the thickness of the liquid-ring layer can obtain a higher mud cake of solid content, but this will be at the basic of the filtrate quality lost.


Therefore, the height of the liquid level baffle should be adjusted reasonably to achieve the best combination of mud cake degree and filtrate quality. In general, many decanter centrifuge suppliers have adjusted the liquid level baffle in advance when the machine leaves the factory. However, due to different conditions on the site, if the operating status of the decanter centrifuge is not ideal, you can communicate with the equipment engineer to make adjustment to the on-site liquid level baffle.

GN can not only provide users with Decanter Centrifuges, but also provide users with turnkey solutions for dewatering process, including solutions for material transportation, classification and dewatering. Rely on GN’s rich production line of separation and conveying equipment, more and more reliable and advanced equipment will be manufactured for users all over the world.

written by Decanter Centrifuge

Mar 20

Refrigerated sewage and sludge are often decompressed by decanter centrifuge. During the process, flocculants may be added to improve the treatment effect of sewage and sludge. Which one should be used and what are the principles of dosage, generally. It can be analyzed from the aspects of sludge properties and pH value.

Decanter centrifuge-GN

First, the properties of sewage and sludge. The difference in its properties directly affects the sludge dehydration effect: Generally speaking, the more difficult the sludge is to dehydrate, the larger the amount of flocculant used. The smaller the sludge particles, the greater the amount of flocculant. The higher the organic content and alkalinity in the sludge, the greater the amount of flocculant used. Cationic organic polymers are more effective in treating sludge with high organic content. Cationic organic polymers with high organic content are preferred. For sludge mainly composed of inorganic materials, anionic organic polymer flocculants can be considered. In addition, the solid content of the sludge also affects the dosage. Generally, the higher the solid content of sludge, the greater the amount of use.

Second, the pH value of sewage, sludge. The pH of the sludge determines the form of the hydrolysate of the inorganic salts. The same flocculant is used for sludge with different pH values, and the conditioning effect is also very different. The hydrolysis reaction of aluminum salt is greatly affected by the pH value, and the optimal pH value of the agglomeration reaction is 5-7. High iron salts are less affected by pH, and the optimal pH range is 6-11. In the sludge with a pH value of 8-10, the ferrous salt with higher solubility can be oxidized to Fe (0H), floc with lower solubility.

GN-Decanter Centrifuge

Therefore, when selecting an inorganic salt, the specific pH value of the dewatered sludge must be considered first. If the pH value deviates from the optimal range of its condensation reaction, it is best to use another one. Otherwise, it is necessary to consider adding the acid or alkali to adjust the pH of the sludge before using the decanter centrifuge to treat the sludge.

written by Decanter Centrifuge

Mar 12

News: GN Decanter Centrifuge for Oil Sludge Treatment to Brunei

This GN Decanter Centrifuge is specially designed for Oil Sludge Treatment and exported to Brunei.

2020.03.12 Decanter Centrifuge for Oil Sludge Treatment

Oil sludge is a mixture of oil, water and solids. Treatment with oil sludge would recover a lot of oil and water for reuse.
It is also an ideal solids disposal solution. The more oil and water are extracted, the more energy and resources could be
saved. GN oil sludge treatment products mainly include decanter centrifuge, oil-water separator and thermal desorption

GN P-series decanter centrifuge is mainly designed for the dewatering purpose. The beach angle of this series is 11
degrees. It is widely used for maximum dewatering requirements of municipal and industrial wastewater sludge. The
dewatering decanter centrifuge is designed for easy separation material include large particle size, high density
difference of solid and liquid, low viscosity, high concentration, high treatment capacity and higher dryness than clarity.
The materials like sludge or wastewater containing fine particles usually need to be added with flocculants to gather the
fine particles condensed into large ones, and then dewatered with P series decanter centrifuge.


Drilling mud, environmental protection sewage, oily sludge, cutting fluid, sand washing water, mineral washing water, soda
white mud, salt mud dewatering, magnesium aluminum emulsion, steel-making wastewater, precision casting wastewater,
construction mud, tunnel mud, mine wastewater, industrial wastewater, organic wastewater, aquaculture wastewater, chemical
industrial wastewater, printing and dyeing wastewater, municipal sewage, river sludge, water plant sludge, lake sludge,
kaolin grading, calcium carbonate, bentonite, Silica, titanium dioxide, calcium sulfate, barium sulfate, conductive film
glass polishing solution, aluminum hydroxide, cryolite, silicate, oil sand separation, landing oil, oil sludge, coal tar,
inorganic fertilizer, Chinese medicine extraction such as taxus chinensis, honeysuckle and liquorice, clarification,
concentration and dehydration of salt crystals, etc.

2020.03.12 Oil Sludge Treatment Equimpent

GN can not only provide users with Dewatering Decanter Centrifuges, but also provide users with turnkey solutions for
dewatering process, including solutions for material transportation, classification and dewatering. Rely on GN’s rich
production line of separation and conveying equipment, more and more reliable and advanced equipment will be manufactured
for users all over the world.

written by Decanter Centrifuge \\ tags: ,

Mar 06

What are the methods for maintaining the decanter centrifuge?

Decanter centrifuges are often used in severe environment and under high workload, so problems will occur sometimes and the decanter centrifuge has to be serviced or repaired. How can we maintain the centrifuges? Here is your answer:


1. When the decanter centrifuge is in the pre-cooled state, the centrifuge cover must be closed. After the centrifugation is finished, the rotor is removed and placed on the experimental table. The remaining water in the chamber is dried and the centrifuge cover is open.
2. The rotor cover can be placed on the platform of the decanter centrifuge or on the experimental table during pre-cooling. Never float the rotor on the rotor without tightening it, because the rotor cover will fly out and cause an accident!
3. After tightening the rotor cover, be sure to touch the gap between the rotor and the cover with your fingers after tightening. If there is a gap, unscrew it and tighten it again.
4. During the centrifugation process, the operator must not leave the operation site. In the event of an abnormal situation, the operator cannot turn off the power. Press STOP and fill in the decanter centrifuge record before pre-cooling.
5. Do not use inferior decanter centrifuge spare parts, or use aging, deformed or cracked centrifuge drums.
6. You can leave only after the last routine safety check using a centrifuge on holidays and evenings.
7. When a failure occurs during the operation of the decanter centrifuge, please contact the technical staff in time when the component is damaged.


GN design and manufacture different size of decanter centrifuge for industry separation with 12 years experience. And GN products have been exported to more than 70 countries with reliable quality and service. Welcome to inquire and visit GN and we are looking forward to cooperate with the clients all over the world.

written by Decanter Centrifuge

Feb 28

The selection of the Decanter Centrifuge is essentially to find a specific machine that can meet the process requirements according to the physical properties of the materials and the process requirements.


The physical parameters related to the selection mainly include:

1.The parameters of Solid-liquid separation: the solid phase concentration of the suspension, the range of the particle size of the solid particles, the weight difference between the solid and the liquid, and the liquid viscosity.
2.The parameters of Solid-liquid-liquid separation: the solid-liquid-liquid 3-phase concentration, specific gravity difference, and viscosity.
3.Moreover, it is also important to consider the machine materials and structures such as pH, flammable and explosive, and abrasion resistance.

Another issue related to the selection is the purpose of separation. Different models have different purposes. Is it to obtain a solid phase with low water content, a liquid phase with high clarity, or both solid and liquid phase content are required, or a higher requirement for one phase and a lower for the other phase appropriately?

During the selection process, we may encounter two situations. One is an industrial problem, such as DDGS project of corn distiller’s grains, kaolin classification, lubricant purification, sludge dewatering, etc. The separation process and equipment have basically matured in the industry. When buying machines, you only need to access the existing Users for reference. The other is about the new problem encountered in the development of new products, which requires the necessary physical property test and separation experiment.

363 Decanter Centrifuge 2

Supporting facilities for Decanter centrifuge
A complete separation system, in addition to the decanter centrifuge, we also need a variety of other equipment and instruments to support it in order to put into normal operation. Normal supporting facilities include:
① Pretreatment device: crusher, shaker, desander, thickener, etc.
② Feeding device: feeding pump, draining pump, screw conveyor, flow meter, agitator.
⑧ Instrument control device: starting device, monitoring device, display and safety device.
④ Lighing, safety protection and cleaning equipment.

written by Decanter Centrifuge \\ tags: ,

Nov 11

GN Automatic Tank Cleaning System is used closed-loop method to continue to clean the mud tank, oil tanks or slurry tank. This GNTC-30B system five key advantages as 1. Compact Design 2. One-touch cleaning 3. High cleaning efficiency 4. Much less personnel exposure to dangers environment 5. Field application proofed subsystem. Specifications as 1. Slop Processing Capability: 30m3/h 2. Water Volume: 7.5m3 3. Total Power Consumption: 40KW 4. Dimension: 8164 X 2416 X 3065mm 5. Empty weight: about 7000 Kg. The GNTC-30C Tank Cleaning system supply fresh water to the high-pressure tank cleaning machine mounted inside the tank. And the integrated pumps will bring the dirty wash water back to the system for cleaning and return clean water back to the tank cleaning machine to reuse. This process will minimize the consumption of water and manpower involved. What equipment included GN Automatic Tank Cleaning System? 1.The Vacuum Pump 2.Filter 3.Solids Liquid Separators 4.Solids discharge Auger 5. Air Pump 6.The Chemical Dosing Unit 7.The Water recycling tank 8. The High-Pressure Water Pump 9.The Tank cleaning machine 10.The Electrical Control System.  The GNTC-30C Automatic tank cleaning system closed loop is a continuous process with waste water cleaning capacity up to 30 m³/h.As an API certified manufacturer, GN Solids Control is a well-known brand for solids control and waste management equipment. The Automatic tank cleaning system is a combination of pumps and GN separation equipment for the tank cleaning business. You are welcome to contact GN Solids America LLC for more details of the GNTC-3 automatic tank cleaning system technology.

For more information please contact GN sales representative at Web:

Add: 6710 Windfern Rd, Houston, TX 770402019111110262

written by Decanter Centrifuge

Sep 30

GN Sold two more 30 inches Decanter Centrifuge to US Customer. A solid bowl centrifuge (also known as decanter centrifuge) continuously separates solid materials from liquids in the slurry and in the wastewater treatment stage plays a very important role. In the whole mud system, decanter centrifuge is the 5th purification equipment. There is a differential speed between the decanter bowl and the scroll, which is created by a gear unit on the industrial decanter centrifuges. The differential speed determines the solid content in the outfeed. GN decanter centrifuges not only easy to install and can be fast to starting up and shutting down but also needs small space operation.GN Solids America LLC has 5 different sizes of Decanter Centrifuge from 9, 14, 18, 22, and 30 inches. Five areas that give GN Decanter Centrifuges advantage competitive advantage in the Solid Control industry.1. Patent horizontal design with SS2304 casting and build for long life usage. 2. Safety locking system for safety awareness. 3. Easy to maintain 4. Designed for a variety of applications 5. more process flexibility and higher levels of performance. GN decanter centrifuges range of applications such as 1. Food Processing (wine, fruit and vegetable juice, coffee and tea, Animal protein) 2. Petrochemical/ Oil (Refining, Dewatering, oil well drilling, Waste oil stream recycle) 3. Waste recycling (Cleaning of wash water, Municipal wastewater )4. Fish Processing (Fish meal, Fish oil)5. Chemical (Herbal medicines, Chemical extraction) 6. Mineral processing (kaolin clay and calcium carbonate)7. Organic chemical industry (Organic intermediate and end products)8. Polymer industry (Thermoplastics for example PVC, synthetic rubber and fibers)9. Inorganic chemical industry (Bleaching agents, Acids, silica products).  GN decanter centrifuges sold worldwide because of extreme performance, reliability, and cost-effectiveness, they are functional, durable and take on key functions in many different industries.201909301720

written by Decanter Centrifuge

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