12 replies to this topic

[Chemster980]

Hi,

I am wondering if any of you know any book or artile that can help me in setting up startup and shutdown procedures for a plant?

Thanks

[Art Montemayor]

There may be some articles. I kind of doubt there are any books. The subject is much too broad and general – although very important and practical in the real world.

The proper, safe, and efficient way to set up a startup or shutdown of a processing plant is dependent on the type of plant, the size of the plant, the process involved, the chemicals involved, the type of unit operations involved, the type of machinery involved, the location, the type of utilities, etc. etc. etc.

Anyone proposing to discuss the above subjects has opened up a can of worms that starts to escalate the moment the different topics are addressed. It is a subject that is much, too much in complexity. What is done in real life is that each process plant is studied and planned for in specific detail. One cannot generalize in talking about how to start up a plant – especially with respect to human safety.

I would never attempt – nor would I trust anyone who suggested it - to start up a plant using a text book. The whole idea is ludicrous to an experienced, old dinosaur like myself who has been around the block for more than a couple of times. Every case is a specific, unique case and should be treated as such – without exception.

If you are trying to find out how to start up a unit for the first time, I can identify with your concern and problem. You don’t know where to start and you are looking for a “recipe” to get you where you want to go. There is no real, secure, and fool-proof recipe. If it is your plant, YOU must ensure that the correct and safe method is arrived at – whether you do it yourself or if you contract out the job. This is the part that everybody gets a large headache and sour stomach over because it means that you are going to have to go over every line, instrument, and specification in your P&ID. It means you are going to have to do overtime in studying all the Unit Processes and Unit Operations, pouring over all the drawings and studying all the internal parts of vessels and machinery involved before undertaking to decide what is safe and what isn’t. If you don’t have a lot of hands-on experience already, this isn’t the job for you. You could really hurt yourself or kill someone else trying to do the job for the first time. I know that this is the real problem area for young engineers – because I’ve already gone through it and lived through it, many times. I’ve had to train young engineers out in the field on how to do it and have had the opportunity of saving several from committing some horrendous mistakes. It isn’t easy and it takes a lot of hard, thankless work and bottles of aspirin – but it has to be done. The bottom line is that it takes experience – the more, the better – to undertake such a venture or challenge with the confidence of completing it successfully. And to get the experience, you must get your hands dirty and accumulate some years in doing so. In short, you must know your process and you must know your stuff – and know it damn well – better than those around you. A book or a magazine article won’t suffice as substitutes.

If I have painted a hard and difficult picture, I’m afraid that it is the correct picture that confronts all who undertake this challenge for the first time and I can't apologize for it. Your best help and support is obtaining experienced and capable engineers around you – in several disciplines.

I hope this experience helps and good luck.

[JEBradley]

I aren't disagreeing with Art per se but sometimes you are told to write a start-up manual and you have no choice but to get on and do it.

I worked for a company that installed small chemical plants at customers' sites and they would typically ask for a start-up and shutdown manual. The document would take the form of a very explicit series of steps that had to be followed. The explicicity was important because, as Art mentioned, there is an inherent danger in letting someone loose on the plant for the first time.

When I say explicit I mean something like 1.) Open valve V21 2.) Start Pump P07 etc. and at each stage include comments as to what the user should be looking for.

I will try to dig out a copy of an old document if it would help.

Just some extra points though which im not clear about from your post. To write a start-up manual you should have considerable experience operating similar plants, or have been involved with the plant from design through to build and commissioning.

When I first commissioned a plant I worked alongside an experienced engineer and we worked through the manual together - he knew how to operate the plant so we were 'checking' the manual was correct - you should never write one blind.

Lastly I want to emphasise that writing a manual is very plant specific but there are commonalities. For example the first step is usually to 'walk the lines' checking there are no loose flanges, cracked lines, open drain valves etc. Make sure lines are fully vented, spades removed. Then you might want to establish the coolant loops feeding your HEx.

I dont want to write too much because of course ultimately it depends on the plant.

[Chemster980]

I would like to thank both of you to write such a concise reply.

JEBradley,

It would be great if you could dig out an old copy of a start-up shut down manual. Since it is a plant specific material, I think it will still be beneficial for me to present my report as closely to industrial standard as possible.

I am actually a final year student doing a plant design, however, I still wish to take things as seriously as possible.

Many many thanks!~!

[Padmakar Katre]

Dear,
As Mr. Art told regarding the topic.It's true as it's a broad topic. But I will share my opinions regarding the plant start-up and shut-down procedure which are quite specific with type of plant it is.
As far as the start-up is concerned you will get the precommissioning,commissioning or initial start-up procedure/instructions manual by the process package licensors.And SOPs are prepared either by the detail engineering contractors duely approved by the Process dept of the process Technologist or the licensor or you can have those made by the experienced people of similar process.

As well we get the start-up procedure for the critical equipments in the plant like your compressors,turbines and so on by the make of the equipments as there are specific requirements or checklists regarding the equipment start-ups.

Now as far as the shut-down is concerned there are two types of shut-downs one is normal shut-down which is planned one and it is taken by reducing the plant load to a minimum (depends on your turn-down) and then complete shut-down.
Now the other type of the shut-down is emergency shut-down whic we will have in the events of power failure,instrument air failure,cooling water failure,steam cut-off or emergency shut-down of any critical equipment which leads to have a shutdown in the plant.
Now considering those all cases the similar process operational experience people come together and they preapre the manuals or the SOPs(standard operating procedures) for each case i.e. start-up,normal shut-down or the emergency shut-down due to any of the reasons stated above.

I hope this will help a little about your query.
And I really appreciate your curiousity to know about this topic and that to being a student.
Any query is welcome.

Regards,
Padmakar katre

[soleh]

Hi, JEBradley, I'm working in 30 MW steam turbine power plant. we use 1 turbine and 2 boiler. for turbine governer controller we use woodward 505E, and for all system we use PKS experion DCS from Honeywell. for 1 last year we have startup the system 4 times. first we overhoul the turbine. our startup was success. second time we have the problem with PAF motor, all system turn off becouse of it. our startup success. third we shutdown the system becouse earth quake. we startup again after fix all damage and success. But 2 weeks latter we have an indication that temperature of metal trust bearing of our turbine is too high so we shut down the turbine. After we check all then we startup the turbine but this time we failed.
we did not have an official SOP for startup becouse until now we have 3 technicians from china (our turbine, generator and boiler made in china). but when i ask them, did they have SOP for shutdown and startup system they said they did'n have.
So i'll be glad if you could send me the document about startup turbine SOP.
my email : soleh_musadad@yahoo.com.
maybe we can share the information

Thank you ver much
soleh

[shan]

As a student, you should eager to learn how to do fishing instead to ask for a fish. Of course, it will not hurt any thing if you just require a fish as a sample for tasting. There are thousands particular ways of fishing because there thousands kinds of fishes. However, all the fishes are in the water. In general, fishing is just drop a hook with something into water.

Let me try to summary chemical facilities start-up and shut-down procedures in general. The chemical plants are like an egg with egg yellow (reactors) in the center, egg white (separators) in the middle layer, and egg shell (utilities) in the outside layer. Some facilities just have two layers (separators and utilities) such as oil production facilities. Some facilities just have one layer (utilities) such as power generation facilities. When you start-up a plant, you should start from outside in (utilities first, then separators, and at last reactors). When you shut-down a plant, you should shut from inside out (reactors first, then separators, and at last utilities). You wonder how about safety. Do you need to tell a fishing guy don’t drop into water? While, you may have to include a lot of safety for avoiding law suites, which may be represented by the foam egg box.

I know that my start-up and shut-down guideline earn you no more score at this time. However, trust me, I am not telling you to throw a hook into sky to try getting a fish. Hopefully, my guideline will benefit you in your future career although it is not as tasty as a fish at this moment.

[Mr. Biggles]

I was wondering if I could receive the startup manual as well. I am currently a senior chemical engineering student at WPI in Worcester Mass, and we are working with a Deethanizer and C3/C4 splitter system that we are designing from scratch (Maybe simple to some dinosaurs on here as you call yourselves) but we are now tasked with starting our process. Since there is basically no literature on the subject I would greately appreciate an example to see if I have been detailed enough and included all necessary steps. My email address is designorder@wpi.edu.


Thank you,
Anthony

[Qalander (Chem)]

Hey shan, I like this; probably missed this early on!

[Padmakar Katre]

Dear,

Good explanation for those who take these things so casually.

[kkala]

Indeed, one cannot write a plant start up without much experience on the subject, but a lot of us have undertaken the task to write an operating manual of some installation. This usually means your company has designed the installation, otherwise the designer would write the operating manual, also containing the start up procedures. Design basis, usual start up and initial start up are usually included here. What can we do in this case? After all how could a student response in such a challenge? Following may be useful.
1. Take information from equipment suppliers. They describe the commissioning / start up procedure for their piece of equipment. You have to consolidate their information on this.
2. This is not easy, because suppliers do not tell the overall picture. Some do a good work, some just copy procedures. You have to compose the whole picture using your judgment and trying to look into installation to feel it (operation, controls, trips, etc).
3. Commissioning and subsequent initial start up is the most critical. Commissioning of each piece of equipment is according to suppliers instructions specifically, but big Project companies have there commissioning standards, which are rather general (details by suppliers). First assume manual operation, with controls deactivated. After trouble shooting, one can activate controls to test them in practice.
4. A lot of checks and tests are necessary to be implemented before: Hydrostatic, flushing, leak, dry out (if needed). Think what utilities every of them needs and how it can be available on time. A furnace or kiln will need dry out of refractory, so fuel should be available.
5. Abundance of spare parts should be available, according to supplier's recommendation. E.g. spare mechanical seals for all pumps having them seems a realistic practice.
If you do not have more info, imagine you start equipment pieces one by one and try to find the safest and simplest way to a result, i.e. to plant full production. Then give your report to supervisor for corrections (to an experienced engineer or your instructor, depending on case.
I have been surprised during initial startups at data having been ignored, while it should have been taken into consideration. Pure realistic technical thinking (not immitation) is quite useful in such cases.
6. Besides the above representing my understanding, there may be other significant things, probably other "schools of thought".

Edited by kkala, 09 April 2011 - 11:50 AM.

[Shivshankar]

chemster980,

You can go through the basic article ''Preparations for initial startup of a process unit'' by Sidhartha Mukherjee- Jan 2005.

You can find it on www.che.com

Regards
Shivshankar
Instrument Engineer

[Profe]

Hi Chemster980

For your help go to the next link:
http://www.cheresour...h__1#entry43018

Good luck.