We use decanters in waste water treatment plant and the nominal operating points are

* 15 to 20 m3/H

* Input dry solid : 3 to 5 %

* Torque : betwwen 2500 à 4000 KN

* Cone angle : 11 to 16°

* Output DS : 20 to 25 % ( organic sludges with 50 to 65 % of organic matter)

3 VFD for GN VFD Decanter Centrifuge

Ok thanks for the quotations. Can you confir the electric cabinet with VFD ( 3 VFD ) are inluded in the quotations.
GN: Yes it is 3 VFD, one for main drive, one for back drive, one for pump drive. But for your application, as it is environmental fileds, you will use a small pump.

I think a pump with 10HP Nemo pump with max capacity 30 m3/H is enough. Right?
Ok for the 3 VFD , what kind of VFD do you use ( Altivar, ABB, Danfoss,...). If possible we will prefer Altivar or ABB. Electricity is 400 V, 50 HZ
GN: ABB VFD is one of our standard. 400V/50HZ is fine for us.

Torque & Torque Control for GN VFD Decanter Centrifuge

Moreover i need to get the following informations :

* is there any Torque regulation included ( differential automatically adapted to the seeting Tors point )

GN: Our PLC control system has two options torque control or currency control. We can use torque for your application. Perfect we use to operate with torque control or in Manual changing the differential speed to find the right Torque seeting point and then colme back to the Torq mode.
I need to have the maximum Torque of the gear box for the 2 models ( kN.m)

* what is the cône angle of the decanters
* GN: 17 Degree,
* Perfect i was afraid to hae a low cône angle but 17 ° is nice.

GN: The GNLW363BG-VFD centrifuge Max Gear Box Torque is: 3500N.M and the GNLW453-VFD Max Gear Box Torque is 7500 N.M, so we recommend you to use the GNLW453-VFD model for your application and your capacity.

GN VFD Decanter Centrifuge for Waste Water Treatment

Q: Do you have any experience with your decanters on environental fields ?

GN: Our centrifuge main application is oilfield, including drilling mud solids control, and Environmental solutions, also we have a few projects for Dredging Slurry Separation, which is close to your case.
For your application, we will increase the speed from 2800RPM to 3200RPM to allow you control the speed from 0-3200RPM.
RE: Ok to go to 3200 rpm as we have to go around 2200 G-force.

If possible, you can send some samples of your material, one bottle is enough for us to study to check, sometimes we may need to do some more modification one our centrifuge to fit for your material. One of our main centrifuge engineer has ever worked for our centrifuge company, they focus on environmental solutions, he understand what fits for the envrionmental solutions.
Also if your have any Data Sheet of your material, you can send to us, like Viscosity, Solids Size Range, Density etc.

RE: Not easy as the product is organic sludge that involve, but we treat around 500 000 m3 per year of this kind of sludges with centrifuges,.....So we know what kind of centrifuge we need.

Concerning sensors i need to know if you have any temperature bearing sensors and vibration safety sensor as standard .

For the price i need to know if this price include the frame to put the centrifuge at 3 m height with stairs ,plateform for the centrifuge and system to trasfer the solid sludge into the groung or in a skip.

As we use polymer, we need to put in the skid a liquid polymer preparation ( maximum 5 m3/h of diluted polymer to iject at 0,5% concentration)

For the pumps i think you can change it but as if we can treat also bentonite slurry With a 50 m3/h we should have a range between 6 to 50 m3/h

I need also to have the typical noise of the centrifuges near the plant and at 1 m

GN: 1) We will choose the pump model with 50 m³/h capacity and adjustable from 0-50 m³/h.

2) We can install 2 Bearing Temp. Sensor and the Vibration Switch as per customer requirements, this is extra price not include in our quotation.

3) The Single Layer Bowl Cover Box centrifuge is noisy is around 85 ,what noisy will meet your need? We can use the double layer cover box to reduce the noise.

4) Price we quoted to you is only the Centrifuge price with 3 VFD, the Cylinder and Cone Material of our Centrifuge Bowl is Duplex Stainless Steel made by Centrifugal Casting.
Other parts main material is SS316L and screw is protected by Tunsteng Carbide Tiles, as you can see in our brochure.

5) According to what you need, we will update the quotation, and give you the price for the pump and the Telescopic skid in separate price for your option.

As a lot of client now need "Clean Water", then chemicals finally upto the show. With a reliable partner, now GN is now also supplying the flocculant unit and coagulant unit, with our centrifuge, to give client a better solution.

The Auto-Flocculant 6000 activity unit can be housed in an exceedingly 20ft normal instrumentation and represents a standard compact system for treating and applying compound solutions. Also can be put into 40ft container with a GNLW series centrifuge. Due to the integrated control system, the preparation and dosing process may take place automatically. An optional feature provides the possibility of referring to a solids dependent dosing mechanism. Based on the data obtained from measuring both volume flow rate and suspension density, the polymer solution is injected into the process in an amount proportionate to the respective solid matter. Such a system will positively exclude unwanted over- and/or underdosing.

The Auto-Flocculant 6000 activity unit is supplied with a liquid compound unit for making certain the automated and continuous preparation of a homogeneously mixed focused compound answer with precise concentration parameters in an exceedingly two-chamber method (product quantity: 3000 l/h) a powder/liquid compound unit for making certain the automated and continuous preparation of a homogeneously mixed focused compound answer with precise concentration parameters in an exceedingly three-chamber method (product quantity: 6000 l/h) a programmable logic controller with bit screen panel for automatic operation flow meters and pressure sensors 2 dosing pumps for transporting the premixed flocculant to the injection purpose.

Two chamber or three chamber, inside container, or outside standing on a skid, can be customized as required.
Also the programme of PLC controlling the system, have two options, one is by timer, another is by water flow. After involve in more and more projects, we will be more professional on all this. Keep tune.

All of us start from crying with nothing, so no offense, and let's try to find out.
1. Good Looking
One of my client told me the main reason he did not purchase from China before as he wanted some beautiful things. Whenever he look at the solids control equipment, or the whole mud system, or even the drawing, must feel like he is staring some beautiful ladies.
Yeah, it is different Hamlet from differnt eyes. whatever, it can not let you feel unhappy or feel ugly.
2. Check the Painting
Not only the solids control equipment, also the mud tanks. Try and check the view from different side of the mud system. People are doing good, you can feel it.
3. Check the Connection
The mud system normally contains several equipment, lots of pipes, flanges. Check if they are keep in line like army, or struggling to be where they are.
4. YOU ARE THE USER
Suppose you are the user, what will you like?
Or any engineering thinking you find from other place. is it simple & friendly enough?

Then if you did not tell anyone you are not professional, it already seems like a professional guy checking. So let's move on.
Now it is time to check how the system working!

As normally the mus system is customized, and the four phase solids control equipment, shale shaker, desander, desilter, decanter centrifuge, are combined in different way, and installed onto mud tanks properly.
Then maybe it is time to:
5.Follow the drilling mud flow, and walk around, check if anything abnormal, valves on the way, and logically, is it running perfect.
6.Finally, take some pictures. Good or bad. Or take some pictures with the mud system. To get a perfect report.

After more and more accidents, also the sea environmental protection comes to PEOPLE's sense, now offshore projects taking care more about the drilling waste disposal. Maybe before it is just a screw conveyer, or a channel for washing to the ship's rail, then slicking to the sea.
So the bentonite, the polymer, cuttings, or whatever you may bring up from the mixture of drilling prodution, go to the sea.
For land rigs, now normally the drilling mud service company, or the contract might handle this with driling waste management system, like the one we just sent to West Africa. It contains Drilling waste management unit equipment list

• One Centrifuge high configuration centrifuge GNLW363BG-VFD.
• One set Cuttings Dryer GNCD930C, fixed speed (800rpm), high configuration dryer, equipped with air line, upgrade scraper and basket screen.
• One set Vertical slurry pump GN50YZ20A-18 for feeding Decanter Centrifuge
• One set Netzsch Brand NEMO pump for flushing cuttings dryer
• One set skid, flexible legs, accessories and electrical control panel system
  Offshore drilling waste normally also contains such equipment, giant contractors for offshore projects normally are solving these problems. While for the design of such systems, different engineers have different ideas. Just like solids control, we also have construction engineering difference. What GN Solids Control insist is simple is beautiful, make everything just simple. Less equipment, more work, which makes the system more powerful.
  There also many differences, between designing onshore projects, the limit space, the whole consturcture, the ambient, sometimes we even have to consider where is it located, as the PH different, then have to use high config stainless steel.
  GN Solids just went to SCIPPE in Shanghai, which is for oil & gas, showed the latest update decanter centrifuge, speed upto 3900rpm. Also more and more good news regarding cuttings dryer feedback to us.