Hi-Chrome Iron and Caustic Soda

[bulkhandling]

There is 2% caustic soda and some cyanide in the ore slurry (up to 25% solids). Slurry temperature can be up to 150F. I need to find right pump material to pump it. Alloy 2205 may be ok except cost is to high. Does anyone know if Hi-Chrome (Hardness 600)is good for this service? Or any other material? Checked rubber lining, CD4MCu, not good.
Thanks in advance.

 

[arunmrao]

High chrome iron pumo offers a cost effective solution for your requirement. We have been manufacturing these pump parts which are used in the mining industry regularly.

 

[EdStainless]

White Cr Cast Iron should work, as long as there is no shock or impact. The stuff is brittle.
I can't imagine that it is less expensive than 2205, CrI isn't cheap.
You could also look at lean duplex stainless grades. I haven't kept up on the cast grades but on the sheet and plate side there are a number of newer, lower Ni alloys that are less expensive. One of the high Mn alloys may also offer better wear resistance.

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Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[metengr]

bulkhandling;
I agree with arunmrao. IF you are handling an ore slurry, your biggest problem will be erosion/abrasion damage to pump internals. If this is a pulverized ore slurry, I don't think 2205 is going to last.

We handle boiler bottom ash slurry (75% suspended solids) using Ni-Hard pump components. Ni-Hard castings are extremely resistant to abrasion and flow erosion damage from suspended solids. The Ni-Hard casting grades are readily available, exhibit excellent corrosion resistance (due to nickel and silicon additions), and are cost effective to use for pump slurry impellers. The only down sides to using certain grades of Ni-Hard castings is very poor toughness (as EdStainless mentioned), and it is not conducive to weld repairs. You must eventually replace worn or cracked pump components.

 

[bulkhandling]

Thank you all for the information. We use Hi-Chrome (similar to Ni-Hard as mentioned by metengr as I can remember) a lot to handle regular slurries. Now I know that hi-chrome can also be used for the condition I mentioned above. Hi-chrome can be much cheaper than Alloy 2205 (about 50 to 80% lower in price as I checked with a few vendors).

But still I may have to use Alloy 2205 in one of the services where besides the conditions I mentioned above, nitric acid (2%) will also be pumped accasionally. Fortunately the pump will run intermittently. Since Alloy 2205 has Brinell hardness of 260 (?), I think it will be ok.
Any thought?