3 replies to this topic

[mervinkhoo]

Hi I am a chemical engineering student who is having trouble with plant design. I am expected to find the basis of plant life which I have difficulty finding online. Can anyone point me to the right reference or website? Your help will be much appreciated. 

Thank You

[Bobby Strain]

The green kind? Sometimes with flowers?

 

Bobby

[gegio1960]

just 2 cents...

plant life is a decision of the owner, driven by the economics of the project.

for oil refinery projects, it is usually set at 15 years.

the target project life will be matched by an appropriate material selection.

normally the real plant life will go well beyond the original figures... as a process designer specialized in revampings and upgrades, it is not very difficult to see equipment built in the 40s. in many countries, the introduction of certifications for the original MOC has made impossible the requalification of equipment built before the 80s (when the certification didn't exist at all or it were made with different criteria, not satisfying the current codes).

good luck!

[Technical Bard]

Often, I see Clients using varied "equipment" or "component" life values rather than an overall plant life.  One could say the plant life is the design life of the longest piece of equipment (such as a reactor, alloy piping or large column).  This is often set between 15-30 years, depending on the industry (if the rate of return is high and the product is expected to be superceded by better products, a shorter life makes sense).  However, some components should have lives of 8-12 years (or a more specific 100,000 operating hours), because it is impossible or very expensive to provide longer lives (such as for furnace tubes, heat exchanger tubes, pump impellers, valves, flow meters).   Finally, equipment in cyclic service usually has trouble making it through very long operating lives unless managed very well.  For example, I have heard of coke drums needing major repairs or even replacement after just a few years, while I know of one operator with coke drums the just passed 50 years in operation.