Gentlemen

I am N.Ramakrishnan, Senior Manager Production for a fertiliser unit in South India. We are manufacturing a complex fertiliser with 16:20 grade with Ammonia , Sulphuric and Phosphoric acids.

In the process we handle rock phosphate at one stage which is stored in a silo. We bring rock from the nearby Chennai Harbour ,by trucks and the trucks unload the material into the silo. Wr use shovels to heap the material and we store about 10000 mt of rock in the silo. Rock is stored in a trapezoid form of about 2 m high and much space is left above the heaps.

I would lke to know what methods can be used to make the heap bigger by discharging the material from the top. Though the silo roof can accoodate a conveyor , we have limited space for unloading the rock. I would like to know whether some other densephase conveying systems can be used for unloading the rock phosphate from trucks directly.

Cost is another factor in this project. We can save some money by high heaping and our management looks at projects with a high rate of return in the range of 25-30 % .

Can you advise us on the methods to do the high heaping ?

Finally I thank you for keeping me informed of the latest in Solids handling

Regards

N.Ramakrishnan

Ramki@murugappa.co.in ■