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[ahmedabdalrahiem]

Hello, I am an senior Electrical engineering student and my graduation project will be in control automation. Our goal is to control an Ethanol fermentation stage with PLC, but the problem is that we don't know how to implement/setup the physical system in college's control laboratory so that it occupies a small part of the lab and gives results that are similar to the ones we will get if we applied the same control approaches on a large size identical process (of course with different parameters). i have seen these kits (for another processes) from the internet(attached) but i don't really understand how to proceed and what are things that i should consider. if someone has a tutorial that describes the implementation this will be great!

Attached Files

•  chem1.PNG   954.59KB   0 downloads
•  chem2.PNG   740.29KB   0 downloads
•  chem3.PNG   438.55KB   0 downloads

[sgkim]

Hi Dalrahiem,

 

First start with process engineer(PE) who is familiar with the process and knows all the operation parameters required for the operation of the unit.   Let him(her) introduce the process - each function of unit, equipment, instrument, operation variables, operating condition etc.

 

Process configuration and operation condition is summarized in the process description(PD) and in the process flow diagram(PFD).  Material flow can be referred  to the material balance(MB), and essential control variables can also be found in PFD.  Good understanding on the process configuration would be essential for your job.  Any question on this category could be answered by the PE.

 

Get the piping & instrument diagram (P&ID).  Basically all the instruments (identify them by instrument tag numbers) should be shown on this P&ID and all of the instrument functions  shall be conveyed to PLC you are going to develop.

 

The P&ID symbols and legends especially related to the instrument is mostly essential for your everyday task until you finish this job. 

 

You must pick up all of the instrumental function with respect to P&ID and also with the instrument schedule(IS), control valve schedule(CVS), provided already by PE.

 

For each unit, each equipment, and each packaged equipment you should raise the following question for yourself and develop the function of PLC's  and implement each details related.   

 

-What (process variables) are to be monitored?

-How the process variables shall be measured? 

-What  (control variables) are to be controlled?

-How should the process variables be controlled ? 

-What is the control mode, manual, sequental, semi-automatic or full automatic?

-What process data are to be recorded? , 

-What event is warned, recorded, messaged ? and how ?

    

-How the graphic panels be grouped?

-What is to be protected, and how?

-What local mounted panel is required>

-What operation data is to be transferred from the packaged unit? 

 

-How to operate them normally ?

-How to operate during start-up ?

-How to operate during scheduled shut-down?

-How to cope with the emergency situation, by human and/or by PLC

-Any what-if countermeasure to be accommodated in PLC function ?

-What is to be included for the protection for the other typical scenario? 

 

As I mentioned at the opening line,  accompany by  good  PE's, 

 

good luck.

 

~Stefano

Edited by sgkim, 18 September 2020 - 10:53 AM.