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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.
At 05:50 PM 5/21/01 -0500, firstname.lastname@example.org 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 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 J. Davis, CHMM
>Industrial P2 Specialist
>133 Ward Hall,KSU
>Manhattan, KS 66506-2508