Forum Message



Name:   
Heading: 1.1.1.1Concrete Plant Mixers
Message:
What is the best concrete plant mixing technique for ready mix plants? And why?
(I know Planatery is best for precast but what about readymix?)


---------------------------------------------
Stewart Cameron


Steward, recently I showed an American friend of mine one of the best ready mix concrete plants I know in the Netherlands It is one of the newer plants.
If I tell you that they have 9 silo's using several cements, separate GGBS, Calcium Carbonate Fines and Fly Ash you understand that they make taylor made concrete od all sorts. From earth moist to SCC, all on a regular base. The way an RMC supplier should be to get better business.
They have both a planetary mixer and a horizontal double shaft mixer, on purpose. When I am back in the Netherlands (from China), I will let you know for what type of concrete they use the double shaft.
If for one reason or the other you do not have the money or ambition, have a planetary mixer. Make the mortar in the mixer and bypass the coarse aggregate directly into the truck the moment you dump the mortar. This way you double the capacity.
For earth dry concrete you have to feed the coarse aggregte through the planetary mixer as well.
Will be in touch for the promised details.
---------------------------------------------
Boudewijn Piscaer


Stewart,

Mr. Piscaer is right, twin (double) shaft mixers are definitely the way to go. The key is separating the coarse aggregate and mixing only the water, cement, sand and additives in the mixer. It not only increases capacity, but is also reduces wear on the mixing blades, improves blending/cement hydration and dramatically improves discharging of the mixer to the truck.

The latter of these benefits (discharging) is the critical element as discharging out of a conventional double shaft is an issue that most producers have problems with. They tend to be too messy and slow to be used effectively in transit mix applications under high volumes.

To overcome this we've designed a high speed augur to mix and transfer the mortar from the mixer to the truck. By eliminating the coarse aggregate and loading it separately into the truck, the mortar can be transferred quicker and cleaner. We've implemented this design at a plant and were able to achieve 60 loads per hour out of a single 6m3 twin shaft mixer.

-Mike Lawson
Jonel


---------------------------------------------
Mike Lawson


Mr Lawson,

I would be interested to see the setup used to achieve this. Please contact me on fyazbeck@hotmail.com

Thanks.
---------------------------------------------
Fouad Yazbeck
 
   Click Here to Reply    Areas
Advertise Here