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RE: refineries

I had not chimed in on this, but I want to confirm what Sherry just said
about steam traps. I was the environmental manager at an edible oil
refinery ages ago. They do most of the same things that a petroleum
refinery does but call them different names (e.g. the fractional
distillation tower is called a de-odorizer). Steam traps are a major energy
and maintenance sink, and a good candidate for preventive and/or predictive
maintenance. All you need to do to evaluate the steam trap maintenance
program for a refinery of either type is drive by it on a cold winter day
and look for the vapor plumes.

Dan Kraybill

At 05:50 PM 5/21/01 -0500, sdavis@oznet.ksu.edu wrote:
>I think you got some good response on your P2 question for 
>refineries. I would like to offer some of my thoughts on the subject 
>having been an operator for 10 years in two different oil refineries. 
>Below are some low tech things you can ask about and do some research 
>on that you may be able to help the company with.
>Steam traps-invariably broken or clogged; are many times bypassed 
>because they are faulty and are huge resource hogs-on the power 
>plant, corrosion chemical use, and operator and mechanics labor. 
>Flow controllers are many times rigged up to prevent faulty readings 
>on high viscosity side streams (especially in colder environments) 
>and many times the operators will just run a steam line up there, 
>crank it open a bit and then forget about it.  A good O&M program for 
>steam trap maintenance can save lots a bucks for  a plant.
>Heat exchangers and energy covered pretty well, but talk to the 
>process operators-are the exchangers being utilized fully-are the 
>bypasses around the exchangers leaking or open for temperature 
>control?  Common problem and many times used for temperature control 
>instead of optimizing the other operations.  Sometimes it's necessary-
>the tower trays may be screwed up, fouled or upset. Corrosion and 
>fouling weren't big problems for us and we ran some of the worst sour 
>crude feedstock-but if it is a problem, I'd say talk to the engineers-
>because some antifouling chemicals have been known to wreck havoc 
>with other operations, such as desalting operations and cooling tower 
>maintenance. Heat exchangers are intricately tied into the process 
>operations and although they can offer tremendous energy recoup, 
>you'll really need to know alot about the processes....
>Heaters:  heater offer a huge opportunity for energy savings.  Look 
>for flame inpingement, even burner distribution  (and use) if a lot 
>of burners have been taken out for repair on a frequent basis, then 
>they ought to look at the corrosivity of the fuel gas or metallurgy 
>in the burner tips.  Preheaters on heaters (heat the air used) and  
>need to be optimized, and also excess air.  Many operators will run 
>with excess air way up around 4-7% so that they can take a bounce in 
>the process (ie: if the feedstock cools and the heater controller 
>tells the fuel gas to open there better be excess air there or you 
>could go O2 deficient-not a good thing and that's why they'll crank 
>the air up. Usually see this after daylight shift when operators get 
>a little more lax--check through control charts or ask operators for 
>a record of their excess air (it's tracked) and then talk to engineer 
>about recommended levels).  Depending on the heater, excess air 
>should be minimal but requires more operator attention to prevent a 
>hazardous situation from developing.   
>Pump efficiency: are operators pinching mechanical valves (suction) 
>to unload the pump or discharge valve to raise the discharge pressure 
>for some reason?  Is there a check valve leaking on the back up pump 
>The are many, many other "little things" to look at:
>Cooling towers
>cooling water flows
>water use for cleaning
>detergent use for cleaning
>compressed air use
>I would work with engineer and head operators at each unit.  Ask the 
>operators where they see excess waste and energy use.  Good Luck!
>Please feel free to call me if you'd like more info.
>sherry davis
>Sherry J. Davis, CHMM
>Industrial P2 Specialist
>133 Ward Hall,KSU
>Manhattan, KS  66506-2508
>Fax: 785-532-6952
>Phone: 1-800-578-8898