15 replies to this topic

[Ra v]

Dear Art;

Thanks for the reply


I must say sorry to you as i am new was unaware of the forum guideline.

Sorry again as i have started this new thread again as i didnt see the options for the attachment in multiple threads.

And let me know that am not a student now . i have completed my engineering in 2010 .

As you said to attach the basic data for the co2 plant. i al sending you the Operational design data supplied by the client. and one more thing regarding the liquifaction the client has not submitted the operating manual so i was confused regading the process.

Here i am sending you the PID of our exisitng plant rated capacity of 80 kg/hr of CO2

Kindly i just want to know how the MEA concentation degrades with temperature and pressure. As given in design data we need to maintain the MEA conc between 14- 16 percent but even though our production is low..

What are the areas we need to look in for good plant performance.

Regarding the Liquifaction i have attached the PID supplied by the clinet but it doesnt have the data for size. type etc etc....

If any other info require please let me know i will try to collect and reply you.

kindly help me.

Attached Files

•  CO2 Plant Operating ParametersRev1.xlsx   73.41KB   30 downloads
•  PID-CLIENT1 OF 2.jpg   86.17KB   55 downloads
•  PID-CLIENT 2 OF 2.jpg   92.19KB   47 downloads

[Ra v]

Dear Art,

Can you pls reply.

Rgs
A Ravi

[Ra v]

Anyone.... pls help me

[Art Montemayor]

Alamuri:

We are going through religious and cultural Holidays here in the USA at present. I have also been sick with a virial attack for the past week. You made the bad mistake of posting multiple postings and now expect us to react within one day after you have taken unilateral action on correcting your own mistake. That isn’t going to happen that fast simply because we didn’t cause the mistake; – you did. Your reason for doing it is not logical; you should admit to yourself that you didn’t do the right thing from the onset and be done with it. I have already replied with important information that corrects and redefines what data you sent in. You have not commented on this and probably think it as un-important. That’s OK; that is your loss.

You now state you are passing on a P&ID from a “client”. I can’t read the P&ID; I clearly explained the importance of being able to communicate with you on an Excel drawing and yet you submit a drawing that can’t be amplified to a larger size that can be read – and much less being able to make comments on it. How do you expect me to show you how this simple plant works if you are not willing to even make the effort to create a drawing that allows us to show you how it works? If you don’t make an effort to help yourself, how do you expect me to? Are you working as a consultant to a client who has the CO₂ plant? Or are you the plant engineer? Please explain the situation and furnish legible, accurate information if you require accurate and professional responses.

You still list your country as the Congo and your location as Kinshasa. Is that correct? Read the Guidelines carefully. We can only help you to the degree that you furnish accurate and detailed information.

If you are indeed a Chemical Engineering graduate, I would expect you to be able to plot the CO₂ process on a CO₂ Mollier Diagram. Do you have one? Do you know what I am referring to?

You still have not answered the basic questions I asked some posts ago: who designed this plant? Who fabricated this plant? Who wrote the Operations and Maintenance Manuals? Do these still exist? How old is the plant? Have you seen the plant yourself? Have you seen all the equipment in the plant? If so, surely you took notes and can explain what you saw, how it works, and even share name plate information with us on each of the equipments. Is that asking for too much???? I don’t think so.

Await your reply.

[Ra v]

Dear Art,

Sorry i dont know how to say but let me explain for the first time i was using the forum like this. so i did mistakes which i will not repeat again.

Regqrding your doubts let me clear.

1. i came to congo a month ago and joined in Co2 plant as a enginner, as i said earlier i dont have experience in CO2.
2. This CO2 plant was designed and fabricated by Ashirwad Carbonic Industries India.
3. This plant was commisined in 2011 may
4. I have seen all the equipments and process of this CO2.
5. Operation and maintanance manuals are not supplied by client, the only basic data like the process description and design data and the two PID sheets which i have forwarded you.
6. i have gone through the process and studied the basic information from google such as Whittmann, sanghi, Unino engg and Bush websites.


So i now i am attaching the process flow diagram in excel as told by you and the process is

First the air and diesel fuel is fed seperately to burner where thy are mixed and then is burned. the flue gas consisting primarly of N2 and co2.this FG is passed through Scrubber where temperature is reduced and SOX are removed by additon of soda ash contionously with the help of metering pump and to maitain level there is a makeup water line.

Then FG is fed to absorber tower where it comes in contact with 15 percent MEA conc, which absorbs CO2 into the solution. the N2 gas leaveing the top of absorber passes through a demister and exhaust hood.

The rich amine sol which ahs absorbed the CO2 is circulated from absorber through a continious regenration system consisting of a stripper and a regenerator where the CO2 is stripped from MEA sol.
This isaccomplished by MES/steam vapours generated in regenerator rising up through the stripper tower Countercurrent to rich sol fed from top of stripper.

The co2 lean sol existing the regenerator is then cooled and recirculate to the absorber to again absorb co2

the co2 gas existing the regenrator system is sent furthur cooled and purification unit where the gas is paased to KMNO4 tower and activated carbon tower and then to a co2 compresoor and again to remove any moisture content it is passed to automated Dryer consting of activated alumina and is snet to storage.

Thanks for the reply in the attached execl file by you saying " I have already replied with important information that corrects and redefines what data you sent in" but i have still doubts in that

1.If there is 25 oC cooling water supply available, why the absorber allowed to operate at such a higher pressure? With this CWS, the absorber should be running no higher than 30-35 oC - which would greatly increase the amount of CO2 absorbed in the absorber.
yes but the temperature of absorber is maintaing around 45-50°C. so was not able to understand how to minimise this temperature

Lean MEA from the "Reactivator" (yes its a direct-fired reboiler) is too hot; the pressure in the stripper is too high. The operating pressure of the stripper is around 0.6-1.2 kg/cm2. is it too high...???? i have observed that lowering the preesue in regenerator the MEA entering into putification train. there is a back pressure contorl valve before the purification train but even though co2 compressor suction pr is maitaing at 0.1-0.25 kg/cm2 MEA entering the Purification train

i hope i have answered all your questions and still if you feels like somthing missing kindly let me know. i just trying to imporve my skills and want to be a good chemical enginner.

Requesting you kindly accept my sorry.

Regards
A Ravi

Attached Files

•  CO2 Plant Operating ParametersRev1.xlsx   111.16KB   15 downloads

[Art Montemayor]

A Ravi:

Thank you for finally answering some of the questions I have previously raised. But why are you reluctant to answer ALL of the questions I raise trying to help you, while you expect me to answer ALL of your questions? Does this make any common sense to you? By starving me of information, you make it exceedingly harder to help you. The posts on this topic now number over 20 (counting the other abandoned thread) and you still have not furnished what I asked of you. You state: “So i now i am attaching the process flow diagram in excel as told by you”. This is not true. You have “cut-and-pasted” the PFD from somewhere else and into Excel. This is an OBJECT, not a drawing. I cannot make comments on it or mark it up, indicating where my comments relate to. I clearly stated that the drawing should be done in Excel – not pasted into Excel. It must feel very comfortable to be lazy and simply cut-and-paste other people’s work and effort into Excel instead of generating your own work.

Since I was sick when doing the comments to your spreadsheet, I made an errata on one of the comments. Note that YOU SHOULD NEVER USE THE SAME REV NUMBER ON AN ENGINEERING DOCUMENT THAT HAS BEEN CHANGED OR MODIFIED. YOU MUST INCREASE THE REV #. That is what revision numbers are used for. Otherwise, you start to cause even more errors and miscommunications. You must control which is the latest and current document. Your Workbook is now Rev 3. Should you change it, it will become Rev4, etc., etc..

I respond to your comments (but not in the same misspelled and badly written fashion):

• i came to congo a month ago and joined in Co2 plant as a enginner, as i said earlier i dont have experience in CO2.
  You shouldn’t be required to have CO₂ experience. If you pay attention to the process, you will become aware that only the simplest of Chemical Engineering principles are applied – UNIT OPERATIONS. There are no complex, difficult Unit Processes involved. (again, you fail to tell us if you are a ChE grad.) This should be a very basic and easy task – IF YOU MAKE AN EFFORT, MAN;
  
• This CO2 plant was designed and fabricated by Ashirwad Carbonic Industries India.
  This company is only 15 yrs old. This doesn’t mean it is bad or lacks enough experience and know-how; it only means it is yet young and doesn’t have a long “track record”. Whoever purchased this plant made a fatal error if they did not specify Operating and Maintenance manuals, complete and detailed P&IDs, and customer service. This information is vital and SHOULD BE OBTAINED.
  
• This plant was commisined in 2011 may
  OK. But has it run successfully all year long? What is the maximum capacity obtained from it? Have there been any troubles?
  
• I have seen all the equipments and process of this CO2.
  If so, then why haven’t you furnished us with this information? You obviously have access to Excel and can do a detailed equipment list and description – as well as a detailed PFD. Do you work for the owner, or are you contracted out to the owner? Please answer this question.
  
• Operation and maintanance manuals are not supplied by client, the only basic data like the process description and design data and the two PID sheets which i have forwarded you.
  Again, what is your involvement? Do you represent the owner? Is the owner refusing to share this information with you? Are you responsible for the plant’s performance while not being allowed to share in the required fabricator’s Operations and Maintenance procedures? Please explain this illogical situation that you relate.
  
• i have gone through the process and studied the basic information from google such as Whittmann, sanghi, Unino engg and Bush websites.
  Why don’t you just go directly to the source for information and guidance:
  Ashirwad Carbonics (India) Pvt Ltd
  Mr. J. P. Kaushik (Director)
  B 90/ A 1, Shiwam Apartment No. 2, Shalimar Garden Extension-2, Sahibabad
  Ghaziabad - 201 005, Uttar Pradesh, India

You can phone, email, snailmail, or use your mobile as well as SMS.

I have more than sufficient experience in designing, fabricating, installing, and operating CO₂ plants – combustion based or by-product. I can easily walk you through a detailed PFD on an Excel Spreadsheet. And I will do this for FREE – as I have done many times in the past. However, I will not do it on your terms which clearly indicate to me that I should generate the detailed PFD.

Note the information I have included in Rev3 of the Workbook. Here I show you not only some of the work you should have generated already, but also HOW to do it. The only thing you are required to do is put together the basic data and drawings necessary to resolve YOUR problem. If you decide not to put any serious work and effort into your problem, how can you expect us to?
 CO2 Plant Operating ParametersRev3.xlsx   472.29KB   23 downloads

[Ra v]

Dear Art,

Thanks for your valuable suggestion.

I must tell you i am not lazy as you said it was cutted and pasted. you are right but the PFD was drawn by me. i was confused to get the equipments and vessels in excel sheet so just managed to draw on paint and pasted it in Excel.

Sorry now i understood how to draw a PID in Excel and i have done it.. if you still feel that its wrong let me know i will try to work it out and make it possible.

Yes i am ChE Grad.

As i said, i came to CONGO last month and working as a plant engineer of CO2 production unit of 80 Kg/hr.
The main problem is with the documentation such as specify Operating and Maintenance manuals, complete and detailed P&IDs, and customer service. The ACI india has not supplied all the relevent documents so i dont have the each and every equipment details .
So now i am collecting all the equipment name plate information and will prepare in excel and forward it later.

This plant was commisioned in 2011 may. But in CONGO; based on the customers( Co2 Clients) requirment we operate the plant and hardly from May 2011 it ran 4 days per week till August 2012 and after that the Co2 requirement was high so we need to operate it continuously but the capacity of plant is now around 1.8 Kg of Co2 per liter of diesel

Have there been any troubles?

• MEA consumption is high.
• MEA entering to Purification unit
• Absorber temperature is Maintaining around 48-52 Deg

Do you work for the owner, or are you contracted out to the owner? Please answer this question.
I am Working as a Plant Engineer.(Permanent position)

Why don’t you just go directly to the source for information and guidance
I have contacted ACI, india but they says, they have submitted all the information, but i asked my manager he said it was not supplied.

I just want to learn what is the behavior of the Amine system and i will seriously work hard to understand it and its my pleasure to deal with such a good experience holders and share their experience and get some knowledge.

Your advice was very helpful and I especially appreciate your offer to connect me. I'll update you as my search progresses.


Thanks
A Ravi

Attached Files

•  CO2 Plant Operating ParametersRev4.xlsx   488.52KB   13 downloads

[Art Montemayor]

Alamuri:

Attached is Rev5 of your recent submittal. Note that there are major discrepacies between what you draw and my PFD. You show several major errors in your PFD and you do not employ a Rich MEA pump. For a combustion CO2 plant, the absorber is at such a low pressure (inchs of water column) that you require a Rich MEA at the absorber. I have never seen or heard of a pressurized MEA absorber in a combustion CO2 process. Please comment on this.

You also fail to show the main vapor-liquid separator after the acid gas cooler-condenser. This is a major piece of equipment and you must indicate what you are doing with the produced condensate.

Happy New Year.

 CO2 Plant Operating ParametersRev5.xlsx   494.25KB   15 downloads

[Ra v]

Dear Art,

Sorry for the mistakes i made in the PID.

Your comments are right. Now i had modified the PID and attached .

We have the Vapor Liquid Separator after the Gas Cooler and the condensate is returned to the Reboiler and part of it is sent to absorber sump if required.

Usually it always lined upto reboiler. Sometimes i have observed that due to pressure difference the whole VL Separator completely filled and MEA Lean will flow to the Purification train KMNO4 Tower.

Regards
A Ravi

Attached Files

•  CO2 Plant Operating Parameters Rev6.xlsx   517.18KB   17 downloads

[Ra v]

No reply

[Art Montemayor]

Alamuri:

I have been bed-ridden and absent from the Forums for over a month due to a severe virus attack.

I have answered your queries with my attached Rev 7 of your workbook. Please study the detailed answers and comments that I make.

From your more complete and accurate process description I can now visualize that you have inherited a very small, compact, and cheaply fabricated plant from a fabricator that has little or limited experience in the CO₂-MEA process. You, therefore, must instill your interest and presence in the everyday operation of this little plant. It is very sensitive to bad operation and MEA losses as well as CO₂ production will suffer if careful and detailed attention is not given to its operation. For example, it is sloppy reporting to state that you have high MEA losses without stating what those losses specifically are. You should report MEA losses as lbs (or kgs) of MEA/ton (or tonne) of CO₂ produced.

Additionally, there is no excuse for allowing the level of condensate to overflow in the LP condensate trap. Proper control and maintenance should be applied. If your equipment is badly (or cheaply) instrumented, you should work to improve that situation to allow you to fully control the process and all production.

I hope this helps you to master this little plant.

 CO2 Plant Operating Parameters Rev7.xlsx   769.12KB   14 downloads

[Art Montemayor]

Alamuri:

In addition to the previous Rev7 workbook I have submitted, I am now adding Rev7A which adds field temperature and pressure data taken from my personal engineering files that have been documented with empirical, field data taken from actual CO₂ plants that I have designed, installed, and operated. This is real data – not theoretical.

This data is added in the CO₂ Combustion Plant worksheet in the workbook. With the exception of the steam data, this is the data I would expect from your CO₂ plant. If it is different from your operation, then you don’t have an optimized system. The liquid CO₂ temperature will vary with your refrigeration capabilities. As long as you maintain the liquid CO₂ pressure below that of your storage tank’s MAWP, you are OK.

One feature that I added in the field and that resulted in successfully reducing the MEA consumption of a plant down to less than 1.0 kg of MEA consumed per tonne of CO₂ produced was the following:

I installed a relatively small, packed scrubbing section after the CO₂ absorber and used the LP condensate produced in the LP cooler-condenser to scrub the nitrogen gas leaving the CO₂ absorber. I found that I could actually measure the amount of MEA recovered in this operation and this increased the economic efficiency of the plant. The resulting LP condensate at the bottom of the MEA scrubber was sent to the base of the CO₂ absorber.

I hope this information helps you improve your operation.

Art Montemayor
 CO2 Plant Operating Parameters Rev7A.xlsx   809.33KB   23 downloads

[Ra v]

Dear Art,

 

Thanks for the reply and it was very usefull.

 

and as now we use around 15 Kg MEA/ 0.7 Tons of CO2 produced , which is too much as per the normal operation.

 

As you said that you have installed a relatively small, packed scrubbing section after the CO₂ absorber and used the LP condensate produced in the LP cooler-condenser to scrub the nitrogen gas leaving the CO₂ absorber.can you please show me the line diagram with the instrumentation included in that.

 

I am involving in the daily plant operating parameter and making the analysis to undesatnd for  any abnormal condition but i dont find any severe conditions.

 

So i  will attach the log sheet to have a look and kindly  suggest if any issue. this is not the actual sheet but i have prepared for myself to analyse.

 

and one more thing in MEA  , I just want to know that; is the PH, Specific gravity of MEA lean and rich will indicate something to analsye about the losses...?

 

regards

A ravi

 

Attached Files

•  CO2 Safgaz.xlsx   69.7KB   14 downloads

[Ra v]

Art

 

I am attaching the changes as well as my equipment data sheet prepared as per field.

Attached Files

•  Equipment List.xlsx   20.5KB   10 downloads
•  CO2 Plant Operating Parameters Rev8.xlsx   808.35KB   17 downloads

[Art Montemayor]

 

A Ravi:

 

I am responding to your latest post in detail and attaching 3 revised workbooks:

• Your MEA plant consumption is 21.4 kg/tonne CO2, not 15 Kg MEA/ 0.7 Tons of CO2 produced.  This consumption is totally unacceptable and must be driving your CO2 operation into bankruptcy.  You must do somethings to reduce this figure:
• Do as I keep telling you – cool down your Lean MEA into the absorber as much as you possibly can.  Also cool down your flue gas into the absorber as well.
• Cool down your CO2 out of the LP Cooler Condenser as well.
• Install an MEA recovery scrubber on the exhaust of your absorber as I indicate in the attached workbook.  Build your exhaust scrubber out of thin cylindrical cans or go to a scrap yard and find an available cheap cylindrical vessel and pack it with homemade Raschig Rings.
• Keep a strict and controlled accounting of the MEA added to the solution in your operating data.

The PH and Specific gravity of the lean and rich MEA will not indicate any about the MEA losses.  It all has to do with the vapor pressure of the MEA going out the absorber and going out of the LP Cooler-Condenser.  Outside of leaks and spills, those are the only places where it can go (assuming you are not degrading the MEA in the direct-fired reboiler).  That is why I am totally against cheap designs using direct-fired reboilers.  You have a very badly designed CO2 plant by persons who are inexperienced and know little of the process and how it works.  I am afraid you are going to have to live with it and make the best you can of it.

This thread has already become much too long and I can’t justify continue answering your posts on it one at a time.  I recommend we close this thread and if you need to continue with questions related to CO2 plant Operations, I suggest you open a new thread titled CO2 plant Operations.  We should also close all your other threads on storage tank, refrigeration, etc.  All these topics fall under CO2 plant operations.

 

I am very pleased by the work you are now doing – such as taking a complete inventory of your plant.  You need to do this much better and in a professional manner, but at least you are starting to show progress.  I like the pro-active actions you are taking like demanding a dew point meter and maintenance service on your refrigeration unit.  You have to prepare yourself for furnishing your operators with an Operating Manual.  They need and deserve this in order to perform their duties according to your instructions and needs – for the sake of afety and profits for the company.

 

You are still mistaken about some operation and lacking in furnishing detailed and engineering information – such as in your equipment listing.  Note how I have arranged your workbook.  That is the professional engineering way to do it.  You must practice efficient and accurate techniques – especially those that are readily available to you such as indexing your equipment list and then hyperlinking it for quick, accurate, and efficient access.  This is common sense applied to your everyday work load.

 

Note that you don’t furnish an accurate listing of ALL your equipment.  All you have done is copy information from some of the name plates.  You fail to compile detailed data sheets for each of your equipment as you should and include these in the workbook.  If you lack blank data sheets, ask for them.  You can download equipment data sheets from our Forum that I have uploaded in the past.  Note that you fail to give diameters, lengths, heights, etc. on all of your equipment.  You will be needing all this information in the near future as you strive to improve your plant’s production and performance.  I envy you because I was also in the same predicament as you when I graduated from university.  I was sent to a foreign country where I had to learn a different language, with no help and little or no monies to spend on repairing or buying new equipment.  That’s how I was forced to re-learn what I had studied and apply it in the real world with initiative and ingenuity.  I succeeded in improving all my plant’s  performance and went on to earn promotion, salary increase, and recognition.   You can too.

 

I hope this helps you out.

 CO2 Safgaz Rev1.xlsx   73.19KB   25 downloads

 Equipment List Rev1.xlsx   63.11KB   20 downloads

 CO2 Plant Operating Parameters Rev9.xlsx   815.19KB   38 downloads

[Ra v]

Thanks for your valuable suggestion Art.

 

As you said, i will stop my all threads and open the new one.

 

I am verry happy to be a member of such a good community to have a very experienced and matured proffesionals who share their experniences to help the new comers and makes their future bright.

 

Regards

A Ravi