Say What You Need To Say

After I decide to say what I want to say to the person who has the authority about something that disturb my head (and my heart), and then being responded by her/him, suddenly positive feelings come inside. There is still hesitation about my decision though. Is it right? Is it better than what I'm doing right now? Will I be happy with this decision? But the most important thing is I don't talk behind, grumble, and feel negative about myself anymore.

So what are you searching in this life? This life is too short to think about things that we don't like. There are sooo many options to do things what we like. If you don't like something, change it, speak up. If you don't do anything about it, than you must ready to accept it.

I remember a song that resembles this feeling of me right now. It's a song by John Mayer, "Say What You Need To Say". Here I rewrite the beautiful lyrics.

Take out of your wasted honor
Every little past frustration
Take all your so called problems
Better put them in quotations

Say what you need to say

(Repeat)

Walkin' like a one man army
Fightin' with the shadows in your head
Livin' out the same old moment
Knowin' youd be better off instead
If you could only

Say what you need to say

(Repeat)

Have no fear for givin' in
Have no fear for givin' over
You better know that in the end
It's better to say too much
Than to never to say what you need to say again

Even if your hands are shakin'
And your faith is broken
Even as the eyes are closin'
Do it with a heart wide open
A wide heart

Say what you need to say

(Repeat)

Sing! :D

Anti-Surge Control for Centrifugal Compressor

Compressor is an equipment for increasing pressure of gas stream. One type of compressor is centrifugal compressor. One thing that is interesting about this centrifugal compressor is the anti-surge control, where other types of compressor are not necessarily required. Why? Because centrifugal compressor is relatively a constant head-variable volume machine or we can say the flow entering centrifugal compressor fluctuates more than other type of compressor. So let's talk about this "surge".

What is surge? Surge is a condition involving volume and pressure fluctuation that happened when attempting to operate at higher pressure ratio than compressor design maximum. See the compressor chart below:

 At chart above, there is a surge limit line that can be reached from stable operating point by either reducing flow or decreasing suction pressure. Surge usually occurs below 50-70% rated flow. Anti-surge control system senses conditions approaching surge, and maintain the pressure ratio below the surge limit by recycling some flow to compressor suction. Recycle flow is taken from air cooler outlet after compressor to prevent overheat. Below is the simple diagram of anti-surge control:

1. Minimum volume

Flow element (FE) senses the flow and flow transmitter (FT) send it to surge control (SC) system. When suction flow to compressor is decreasing below minimum set point, surge control system order the surge control valve (SCV) to open and recycle discharge flow to suction flow until the surge condition is passed.

2. Pressure limiting

Pressure transmitter (PT) senses process pressure and send it to surge control (SC) system. When discharge pressure exceeds the set point pressure, surge control system order the surge control valve (SCV) to open and recycle discharge flow to suction flow until the surge condition is passed.

For example, I take the PHE-FOXTROT Compressor P&ID snapshot as seen below:

At P&ID above, there is two sensing that send information to surge control system, which are FT-100 (for sensing inlet flow) and PDT-100 (for sensing differential pressure between suction and discharge). The surge line is flowing through air cooler (HAL-100) outlet to gas scrubber (MBF-100) inlet via surge control valve (SCV-102).

If you want to read detail sharing knowledge about this anti-surge control, write on your email in comment and I will invite you to shared folder on Dropbox. Thank you :)

References:
GPSA Section 13 Compressors and Expanders

Unwanted

Have you ever felt in position when you are a part of a group but a condition made you feel you are not part of the group, or when you thrown from one place to another place without knowing which place is the place that needs you, or simply feeling unwanted? I have.

I can not tell you the details, but I think about that problem for two days, feel that I am worthless (oh sorry, for having that negative feelings), tell some people that I trust about this feelings many times. And than I realize.. A problem is not the problem, a problem is how you react the problem. Today I make decision not to drawn into the problem. I made the conclusion that this problem is not a BIG problem. Like adding one routine in a day won't hurt you. Or this problem actually is not my authority to decide. The most important thing is I can still do what I have and need to do here and make the best of it, every SINGLE day. And I still get what it should be. As simple as that.

Although there is still a lump inside my head (and my heart), I try to accept it. If I can't accept it, better to talk with the person that has the authority. Please pray for me so I can talk properly, without adding any bad emotions on it. Hehehe.

That's all for my story today.

Keep smiling :)

Why Some Fractionation Columns Having Different Diameter?

A fractionation is a unit operation utilize to separate mixture into individual products. The separation involves separating components by relative volatility. Below is the example of fractionation schematic diagram:

 

Heat is introduced to the reboiler to produce stripping vapors. The vapor rises through the column contacting the descending liquid. The vapor leaving the top of the column enters the condenser where heat is removed by some type of cooling medium. Liquid is returned to the column as reflux to limit the loss of heavy components overhead.

Some type of fractionators are demethanizer (top product is methane, C1), deethanizer (top product is ethane, C2), depropanizer (top product is propane, C3), debutanizer (top product is butane), distillation column (products are naphta, kerosene, etc) and many other type fractionators, depends on the products to be made and the feed composition.

The interesting thing is the diameter of fractionation column can be different between the top and bottom section. Why? Let's see the example below:

 

 Demethanizer

 Atmospheric Distillation Unit

On demethanizer figure above, it shows that the top section has larger diameter than bottom section, looks like a bottle upside down. While on atmospheric distillation unit, the bottom section has larger diameter than top section and looks like a bottle.

After having some discussions and reading some references, I try to conclude the answer of this question. It depends on the feed composition that enters the column. When light components is more than heavy components, the top section column might be having larger diameter than the bottom (like demethanizer). Vice versa, when heavy components is more than light components, the bottom section might be having larger diameter than the top (like distillation column). This answer is only a philosophical answer (I know this is still a shallow answer hehehe). Further calculation and sizing is needed to get more precise and detailed answer. Anyone would be adding or correcting my answer? I am very welcoming it. Let's discuss! :D 

Reference:

- GPSA Section 19 Fractionation & Absorption

- http://nptel.ac.in/courses/103102022/evaluation%20of%20crude%20oil/images/2.5.3.jpg

- Discussion with senior and friend: Abang Joni, Mas Andri, and Togel (thank you)

What I Think and Feel About Being Process Engineer

What kind of a job is process engineer? Process engineer is a people that designs system and equipments in process industrial, such as in oil and gas industry, petrochemical industry, consumer goods industry, food industry, etc. For example, fuel that we use for our vehicle. It comes from petroleum. To change the petroleum that we get from bowels of the earth, to oil fuel that can turn on our vehicle machine, we need to process the petroleum in a system that contains many equipments. We usually call that system and equipments as refinery. Process engineer designs refinery (but refinery is only one of example what a process engineer usually designs). Those are explanation that I usually tell to other people who ask about my job. A little bit difficult huh?

How can I have a work as process engineer? Because I take Chemical Engineering major in college. Many options can be chosen by Chemical Engineering graduate. We can be a lecturer (assistant), an engineer, a consultant, a manager (assistant), even an entrepreneur, or we can work in a bank, in ministry of government, and any other work place. 

After I graduated, I was not really know about what job should I do or where place should I work. I follow some recruitment process at campus. From oil and gas company like Chevron and Pertamina, oil service company like Schlumberger and Halliburton, FMCG (Fast Moving Consumer Goods) like Unilever and Kraft, engineering company like Tripatra (company where I work now), fertilizer plant like PKT Bontang, until milk factory like Ultra Jaya. Those are the company that I can remember. How is the result? Chevron, I failed in psychological test. Pertamina, I didn't come to the interview in Jakarta. Schlumberger, I didn't pass the English question test. Halliburton, I didn't pass the group discussion. Unilever, I failed in user interview. Kraft, I came late to the test. Tripatra, I didn't come to the test. PKT Bontang, I didn't come to user interview since I feel the location of the plant is far from my family. In the end, I wanted to work at Ultra because the location is near my grandma's house but I failed again in the writing test!!! What a life. 

Between my waiting time to get a job, I actually worked in my lecturer's laboratory, do some research for him. And then came the offering to be a lecturer in my campus. And I tried it. At that time, bachelor's degree only can be a lecturer assistant. If want to be a lecturer, I must have a master and doctoral degree. Thinking about learning again as a student and there is a chance to learn abroad made me enthusiast. For several months I worked as lecturer assistant in my campus but it turned to feeling that I didn't belong there. I think it was because my communication skill is not good, especially to make connection with other lecturers and other employees in my campus. And I felt very very down, I blame myself. Why am I an introvert person? Why I don't have good communication skill? Why I don't have that soft skills that always been told by many people that when you are start working, you not only need intelligence but also soft skills? Why? Why? Why? I kept blaming myself and start taking conclusion that I am a FAILED person. I study in one of best college in this nation. I pass the test to study in one of excellence major in this college. I have graduated with a good grades. But I don't have a job, either survive in my choice to be a lecturer.

But fortunately my family always encouraged me to apply another job. Just try the opportunities out there. Thank you for my sister, she gave me a vacancy info at her work place, Enerkon (engineering local company). I apply to Enerkon, also tried apply to IKPT and Garuda Food. It turned out that Enerkon gave faster respond than other company. I interviewed two times with HRD and user, and I passed it. Thanks God. And the journey as process engineer begin.

I can not say that my journey as process engineer is a smooth journey. In the beginning time I worked at Enerkon, I got confused. Why there was not any job for me to do? At that time, oil and gas project is kind of slack. But fortunately, gradually, there was a job for me, from helped my senior's work until I was trusted to do my own job and involved in a project. I was happy when I was working there. The people are kind and still have a great kinship feelings between the employee. But I didn't stop there. My confidence has coming back and after one year worked in Enerkon, I braced up myself to apply to another company. I tried Singgar Mulia (also engineering local company) and Total. But.. I failed again in Total. In the second interview with HRD Manager (hahaha). Fortunately I passed Singgar Mulia interview although most of question that asked to me whether I have done some documents or not, my answers were mostly not (hehehe). 

Singgar Mulia, a place where I work for three years. Also not smooth as my guess. I can say, higher salary means higher responsibility (like great power means great responsibility in Spiderman movie). But I have not ready actually. I kept compare it with my previous company because in Enerkon, I just feel comfort. New company means new place, new environment, new friends.. And I came back to my trouble: communication skills. Because in new place, I must start all over again. But Allah is good to me. Singgar Mulia was still giving me opportunity even I did a fatal error there. But I tried to survive after all, with support from my family and my boyfriend (that now is my hubby). The fact that I must saving money to hold a marriage ceremony, gives me encouragement to keep working (hahaha). But I get more than that in there. I get knowledge, experience, and friendship. Until the farewell.

Now, I work at Tripatra, a company that I had applied when already graduate but I didn't attend the test. Is it a destiny? Maybe. In the beginning, same as when I worked in Enerkon and Singgar Mulia, I don't have a job to do (hahaha) because the project that is promised for me has not started yet (until now). So what am I doing to do here? Fortunately, there is a project that needs a process engineer but located not in Tripatra Head Office. So, I am mobilized to Arkadia, doing PHE project. Yes, PHE again, after in Singgar Mulia I also do the PHE projects. But it's ok, better than doing nothing right? Actually, I am now in stand by position because the PHE project has been finished. Then I am contemplating again. What should I do?

I remember, when I was in stand by position, neither in Enerkon and in Singgar, mostly I do nothing. When there is an engineering question in my mind, I end up with forgetting it and not find the answer. But there is a moment that I am (very very) regretting this part of me. That happen when I interviewed in Saipem. The interview was so technical. All of process engineering stuff was asked to me. And.. some of the interview questions actually are questions that had appeared in my mind before. But because of my laziness, I never try to find the answers. I was being told by the interviewer that with my number of experiences, I should know the answers. And than I am being compared with my college friends that has work there shortly after graduated, that my knowledge is far below their knowledge. I am very sad but I know, this is my own fault.

Here in Tripatra, I meet a senior that always encourage me to do every day learning even though we don't have a work to do. In the beginning, I feel burdened by his questions. But I realize, this is the right way to pass the day if we don't have a work to do at office! Because in the end of the day, after I try to find the answers of his questions (and get the answer), I don't get bored in office and somehow I feel worthy to come to the office (not feeling guilty because of leaving my daughter at home) as well as I feel worthy as process engineer.

And then I remember I have this blog. Writing is one of my passion actually. And it's a great idea to combine a thing that I do (my job) and the thing that I love (writing). So I am starting again to write, not only write post as a mother, but also write as engineer, like the title of my blog. Multiply engineering post than privacy post. Hope I can consistent doing it!

Last words, a knowledge is not about your grades in college. A knowledge can be our knowledge if we have tried doing it, feel understand about it, and share it to other people. That's what I do in my blog now. After doing something in my job, I try to understand it and post it to my blog so I can change that knowledge into MY knowledge. It's OK if you don't know about something because in workplace, we work as a team, but never stop learning. Never pass a day without doing something useful. And after all, I should stop saying that I don't have a good communication skills. Because writing is one of way to communicate, right? Although I admit that I have to improve my verbal communication ;p

Just be yourself dear.. Find what you love to do, do what you love and love what you do. If you want have friends, be a good friend. As simple as that :)

Oh God.. this writing is somehow relieving me and my worries.. :)
Do your best today! So you won't regret it.
Past gives experiences, future gives hopes, but still.. live the present.
Because the sentence itself tells us that it is a present.

Cheers :)

Spreadsheet in Hysys

A process engineer might be most familiar with this software, Hysys. Have learn it since in college and earlier operate it before knowing other process engineering softwares, does not mean I am mastering it (hehehe). One of Hysys function that I already understand is Spreadsheet. Once again I say, I was learning about that Spreadsheet in college, but I just already use it to develop simulation at work not long before I write this post. So please forgive me, my lecturer :p

Back to the topic, you can find Spreadsheet in the object palette. It's like having simple Excel in your Hysys. You can calculate a variable you need, from other variable that has stated in the simulation and directly input it to the empty variable without copy paste it. Check this steps out.

1. Example case: there is a fluid that contains oil, water, and slight gas. Available data:

    - Fluid pressure and temperature

    - Oil and gas composition

    - Oil flow

    - Gas oil ratio (ratio between oil and gas, usually in bbl/scf)

    - Water cut (water percentage in water and oil mixture, in %)

Below is the PFD:

Actually, the three phase separator is a dummy. ZUB Comp 2 stream = Oil stream. The objective of the simulation is to get Gas, Oil and Water stream from available data.

2. Step to appear Spreadsheet in PFD:

3. Double click the Spreadsheet icon in PFD, then appears table like picture below (after click Spreadsheet tab)

- Type the variables that corresponds with calculation in column A.

- Right click B2, choose import variable. And then choose object Oil and variable Actual Liquid Flow.

- Input GOR data to B3

- Input formula to B4 to get Total Gas (MMSCFD) = B2*B3/1000000

- Change variable type to Std Gas Flow 

- Right click B4, choose Export Formula Result

- Choose object Gas and variable Molar Flow

- Input Water Cut data to B5 (in fraction)

- Input formula to B6 to get Total Water (BWPD) = B5/(1-B5)*B2

- Right click B6, choose Export Formula Result

- Choose object Water and variable Liq Vol Flow @ Std Cond

- If you want to know Total Liq (BFPD), input formula to B7 = B2+B6

Done! We get convergent Gas, Oil and Water stream with known liquid flow (from available data), calculated gas flow (from GOR), and calculated water flow (from Water Cut).

Yeayyy! :D

PIPESIM 2013 New Interface

PIPESIM is an engineering software from Schlumberger that used for pipeline or well simulation. A process engineer usually uses this software for hydraulic calculation across pipelines. Pipelines is a long pipe that connecting two places to distribute fluid, can be gas, oil, water or mix of those. The location of pipeline can be in offshore, onshore, underground, or above ground. Hydraulic calculation is needed whether to know pressure drop across pipeline or what size should be a pipeline, in certain flow, pressure, and temperature. The hydraulic calculation is using some correlations formula like Hagedorn & Brown, Beggs & Brill, and many other correlations.

In PIPESIM 2013, the software interface is quite different than older version. The new interface is like other software new interface (like newest version of Flarenet), following Microsoft Office interface. Actually it can be easier to operate but we need to familiar first with it. This post contains the steps to build pipeline simulation with new interface of PIPESIM 2013.

1.  When opening software PIPESIM 2013, the first window that occurs is Workspace, like picture below:

There are two options we can choose: Network and Well. Choose Network - New to build new pipeline simulation (either single branch or network). There is also License Information which state the license we can use, indicated by green button. Basic licenses we can use are PIPESIM single branch and Multiflash base. If want to use other license (indicated by red button) such as PIPESIM network modelling, OLGA, etc., we shall contact Schlumberger to buy the other license.

2. After choose Network - New, appear the new workspace where we can build the simulation. The pipeline simulation that I build is a single branch type. A platform named ZUD is connected to Junction named ZUJ-1 via pipeline under water (offshore). Between pipeline and platform, there is riser to connect both of them. Here is the picture:

Beside Workspace tab, there are Home, Setup, Insert, and Format tab. Click Insert to input Source, Riser, Junction, Flowline, and Sink like the picture above.

3. Double click Source, then will appears table below. Insert Name and Temperature data.

4. For fluid model, click New.. button to input the fluid data in Source table. I use black oil fluid model since available data support this fluid model. You can choose black oil or compositional by clicking it on the Setup tab. Fluid data table is like picture below:

Input Name (in the top of table), Water Cut, Gas Oil Ratio, and API (in Properties tab), also Viscosity Data (in Viscosity tab), based on the data. Click Close, and choose ZUD as Fluid in Source table.

5.  Double click Riser to appear table like this:

Input pipe data (inside diameter, wall thickness and roughness), platform data (platform height), profile data (horizontal distance, seabed depth, and use as downcomer or not), and heat transfer data (U value type in air and water section).

6. Double click flowline to appear table like this:

Input pipe data (inside diameter, wall thickness and roughness), profile data (rate of undulations, horizontal distance, elevation difference, and depth at start), and subsea heat transfer data (U value).

7. Double click another Riser to input data, same as point 5.

8. Double click Sink to appear table like this:

Input name, pressure, and liquid flowrate.

9. Click Setup -  Simulation to input flow correlations like picture below:

Input flow correlations for vertical flow, horizontal flow, and single phase as per available data or Company requirement.

10. Click tab Environmental to appear table like this:

Input general data, air data, soil data, metocean data as per available data or Company requirement.

11. After input all necessary data, the simulation can start to run. In my simulation, I want to know backpressure at ZUD Platform. Click on Source (on pipeline modelling) - Home tab - P/T Profile to run the simulation. If we don't click Source (on pipeline modelling), P/T Profile can not be clicked. Only Network Simulation button that can be clicked. But since the pipeline modelling is a single branch, we can choose P/T Profile for this calculation. For Network Simulation, another license is needed to activate it. Below is the P/T Profile table that appears after clicking it in Home tab:

Choose inlet pressure as calculated variable and input outlet pressure and liquid flowrate as per available data. Click Run to run the simulation.

12. The profile result is as per figure below:

From figure above, we get the inlet pressure = 56.77 psia.

13. To know another variable beside pressure, you can click "Show grid" and appears table like this:

14. If you want to add another variables beside on the table above, click "Select columns" and search variable you want to add (for example viscosity, velocity, etc). If you can not find variables you want to add (for example density), go to Setup tab - Simulation - Output variables tab. On report template choose Flow Assurance, click Profile button, search density. You will find some density variables like flowing gas density, flowing liquid density, etc and than clone it and name it (for example as ZUD). The appearance of output variables will be like this:

 

Back to P/T Profile, show grid, select columns, and now you can add density in the table.

15. If you want to print output summary or output details make sure you go to Workspace tab - Options - Advanced and check the "Show engine output files" like this:

16. Output summary appears beside the profile result in P/T Profile. Right click on output summary to save it in text format.

17. Output details appears beside output summary. Right click on output summary to save it in text format.

18. To change units you want to use, go to Workspace tab - Options - Units.

Last words, this new PIPESIM version actually is facilitated with message center, validation and progress monitor which located at  the bottom of the window. There are message for Errors, Warnings, and Information that we can use for building simulation easier even though we have not familiar with this version. You can also visit Help in the Workspace tab if there is something you can not understand about simulation.

So, enjoy your new PIPESIM version! :D