Control Valve. Caustic Liquor/Alumina.

[Vienta]

Ladies and Gentlemen.

I have been asked to provide a control valve for use on Caustic liquor with traces of Alumina. Details at this stage are a little schetchy but currently they are useing a 25mm ceramic lined butterfly valve with a ceramic disc.

I beleive there must be a better valve than this as these are not lasting long. I feel that the type of valve is not suitable but I'm sure there is something out there that works better than this.

I suppose at this stage I'm looking for a type of valve rather than getting to far into the process evaluation stage. This, I can do when, I have found the correct design.

I look forward to a reply.

Kinds regards.

 

[fredb]

Hello,

You might want to consider a ball valve or a plug valve. You don't say how the valve is deteriorating so it's hard to recommend a replacement. For materials NI-RESIST Type 2, ASTM A436-59T Type 2 should be a good choice.

 

[Vienta]

fredb,

Thanks for your response.

The current valves that are being used are Keystone ceramic lined butterfly valves. We have also designed a butterfly valve a re-profiled the internals to achieve a better life but we are coming to the conclusion that this valve design may not be the best.

Thus we are looking for ideas on other types of design. The problem with this process is the velocity which is causing severe wear not only on the disk but also the inner body. In particular, where the process is deflected from the disc.

Thanks

 

[kenvlach]

Can you add some chelating agent to the process solution to prevent precipitation of the abrasive ceramic phase?

In the metal finishing industry, especially in the hot caustic etching of aluminum, sodium gluconate is added to prevent the deposition of alumina and NaAlO[sub]2[/sub] on the tank walls and heat exchanger. The sodium gluconate can even clean off scale deposits from tanks containing 125 g/L of dissolved Al. Chelating agents are also used in caustic electrocleaner solutions.

 

[hammerr]

You may want to look at a Masoneilan V-Log or Lincoln log control valve that would limit the ultimate velocity to a manageable level. Joe Shada at 508-586-4800 or jshada@masoneilan.com can help if your interested.

 

[tsapa]

Try a fully-ceramic valve, like Fujikin's Cosmix valve. They're made of 99.5% alumina and are extremely wear resistant. They warranty the valves as well for up to two years.

http://www.fujikin.com/Products/valves/ceramic/cosmixballvalve.html

 

[abcmex]

you may review the literature of control valves that are adequate for handling erosive streams. Quarter-turn valves (like ball, plug, or butterfly valves) are not the most adequate, in general terms, for this service.
Try in internet a search with keywords like control valve, erosion and ceramic and check the results like

http://www.flowserve.com/valves/brochures/pages/survivor.stm

 

[MedicineEng]

Vienta:
Just a guess, did you think about a PFA or PTFE lined valve to handle the corrosion issue? Is you are instersted, please see the site of ITT Richter.

http://www.ittrichter.de/001index.htm

Hope that helps.

PR

 

[prewrathrap]

I do not like butterfly or plug valves for throttling valves. If you can use lined valves and line size is not too big I can recommed the Fisher RSS globe. If line size is
not larger than 2" I know of a company that makes a lined v-ball.

 

[JimMetalsCeramics]

http://www.nilcor.com/prod05.htm