Past interview questions

Starting questions:

Tell me about yourself

Why do you want to work for Total?

Why should we choose you over the other candidates?

Why did you choose Chemical Engineering?

Technical questions:

Explain the working mechanism of a distillation column – Total 2012

Vessel used for separating a mixture into its different components by taking advantage of the differences in boiling point. Gas/vapor (lowest boiling point) comes out the top, while liquids(highest boiling points)come out the middle and bottom. A reboiler is present at the bottom, and a condenser is at the top to maintain vapor liquid equilibrium inside the column.

Explain the working mechanism of a heat exchanger. What affects the efficiency? Briefly.

It is used for cooling of heating a fluid. It has a shell side and a tube side. To heat up a cold fluid, the fluid to be heated (the cold one) is passed through the tube side, while the hot fluid is passed through the shell side. The fluids don’t mix since the tube are enclosed metal tubes. The efficiency of the heat exchanger decreases over time as the tubes get plugged, reducing the heat transfer coefficient of the heat exchanger. The tubes should be cleaned out periodically to avoid this issue.

Explain the working mechanism of a pump – maybe flowserve

A pump is an equipment used for moving fluid (slurries, liquids, gases) from one point to another. It uses an impeller (fan-like plate) to move the fluid from low pressure to high pressure while keeping flow rate constant.

Importance of baffles in a heat exchanger

Baffles enable back mixing of the fluid on the shell side, which creates a turbulent flow, which in turn increases the heat transfer between the shell and the tube.

What factors increase pressure drop in a pipe

Pipe fitting like valves, venture meter, bends, elbow (90o, 45o) and turns causes high pressure drop in a line

What valve is best for flow control?

A globe valve since it gives the least pressure drop. It is also good for throttling. A gate valve is not suitable for flow control. A ball valve is good for flow control.

If I open a refrigerator and allow the hot air to flow out, the whole system is enclosed in a room; will the room get hotter or colder? Explain – Enterprise Product 2011

Thermodynamic problem: Temperature will slightly increase, but you will not feel it unless you have a thermometer to actually measure it since the change is very small. Deals with the compressor doing more work while trying to maintain the temperature set point of the refrigerator. Since it does more work, more heat is released to the environment than cold air can produce, so the room will get slightly hotter

How would you increase the density of gas flow

PV=nRT problem. Also, you know that density = mass/volume.

If you want density to increase, reduce the temperature of the gas or you can reduce the volume of the gas.

Behavioral based questions:

Leadership/collaboration skill:

Describe a time when you caught someone compromising the ethics and standard code of your school/company? What did you do to handle the situation?

Tell me about a time when you didn’t agree with the opinion and ideas of a fellow team member. How did you persuade him/her that your ideas are better

Describe a time you had to get along with someone who you didn’t like Tell me about a time you had a problem member on your team, how did you motivate him to

perform his tasks/responsibilities

Critical thinking:

Describe a time when you tried a new idea and it failed, what did you learn from the situation and how have you applied it afterwards?

Tell me about a time you made an improvement in a project or a class room setting. Tell me about a time when you went above and beyond your call of duty to get a task done What has been your biggest challenge in school/work? How did you overcome it?

Taking Initiative:

Describe a situation when you were not given all the information you needed to complete a project. What did you do, and what was the outcome of the project?

Time management:

Describe a time you overwhelming workload and couldn’t meet a deadline, what did you do to mitigate the problem, how did you handle the situation?

How have you been able to manage challenging work loads and maintain work/personal life effectively?

My most recent ones:

Describe a time when you had to be the voice of opposition on a team or prove to your leader/team that your idea was the best. What did you do and how?

What is your definition of good performance? What is your definition of success? Which goals have you set lately and what steps did you take to meet those goals? What is your most preferred method of communication?

Random:

What software are you familiar with using?

Why should we hire you over other candidates?

What are your weaknesses?

What are your strengths?

If I asked your peers/classmates about you, what would most likely be their responses?

How would you manage the lifestyle that comes with this job?

What is your preferred method of communication?