Process Instrumentation issues

[mdahan]

Hey everyone,

I am new in the field of chemical engineering and having a bit of trouble finding the correct construction of material for the instrumentation in the processes that we are working with.In tank Ph meter, temperature probes, and level gauges are breaking down or corroding. We work with acids such as sulfuric acid, Hydrochloric acid, sulfamic acid, and copper and nickel metals. I am hoping i can find good companies or a sheet in which I can go off of.
Im sure you all will help with this and thanks.

 

[Berenger]

Read the NACE guidelines. The most recent standard does list materials that conform to NACE standards (SS, CS). Also, go through manufacturer data sheets for the instruments. Most manufacturer's will include a statement on whether an instrument was made with NACE-compliant materials.

I am currently doing the same thing for valves, meters and other instrument. Also, some websites such as valvesandinstruments.com have a huge database that you can search through.

 

[moltenmetal]

I've got only one thing to say to you: choose corrosion immunity over corrosion resistance whenever possible. Non-metallic components satisfy that demand, as long as temperature and pressure combination isn't too high. Otherwise, because you've specified neither concentration nor temperature and given a wide range of acids, tantalum is the only thing on offer amongst the metals- and that material is fraught with application difficulties and cost.

 

[silebi66]

PH measurement is best to control water chemistry and avoid corrosion and scaling, and you can refer to the following standard.ISA S5.1 Instrument Symbol and Identification, NEMA ICS 6 Enclosures for Industrial Control Systems,NEC 70 National Electric Code. Thanks.