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The best method for loading the hopper

Q: We are setting up a polyester and alkyds resins manufacturing plant, having two production lines each consisting of a 12.5 m3 reactor and a 25 m3 blender. To manufacture alkyd and polyester resins, we have to charge the reactors, as per formulations, with chemicals (solid powder materials) like phthalic anhydried in flakes form, maleic anhydride in pellets form — size 1/2 inch by 1 inch — and isophthalic acid in powder form. The top of the hopper is attached to the reactor will be at a height of 25 Mts. What is the most practical and least costly method for loading the hopper?

A:

There is not enough information to make a definitive recommendation. I'd need to know the location in the building, the type of structure, what kind of supports are available, the floor loading, what other equipment is in use, environmental conditions (temperature ranges, humidity, seismic activity, air pollution control regulations and several other site factors) and how the materials are received and/or stored on-site. I've used pneumatic conveyors in some cases, lift-tubes (a variation of pneumatic) in other cases, and bucket elevators for others. Also, if labor is inexpensive and the material is received in bags, I'd use a freight elevator and have the material manually dumped.

The choice is difficult without having a complete picture.

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