Interview questions


  1. What is the Driving force for fluid flow?    Answer click here
  2. Why distillation? Why not adsorption or leaching ? Answer click here

  3. Pressure drop equation for horizontal pipe line in laminar flow condition?    Answer
  4. When reflux ratio to the column is minimum and zero, what are the requirements in column ? Answer 

  5. Define Intensive and extensive properties, give examples for them ? Answer
  6. What is jigging and where it is used ? Answer

  7. Pressure drop equation for Inclined pipe line in laminar flow condition?(Inclination by an angle )     Answer
  8. What is meant by differential distillation? Ans: Click Here
  9. What is dew point ? Ans: Click Here
  10. What is first order system  or which system is called a first order system ? Ans: Click Here
  11. Transfer function for PID controller ? Ans: Click Here

  12. U-tube manometer is first order system or second order system? Ans: Click Here

  13. Laws of crushing ? Kick's law, Rittingers law, Bond's law ? Ans: Click Here
  14. Draw the inclined manometer diagram?    Answer click here
  15. Write the pressure drop equation for inclined manometer?    Answer
  16. Use of inclined manometer?    Answer click here
  17. What are differences between pipe and tube?    Answer click here
  18. Types of pumps?    Answer
  19. Draw the centrifugal pump diagram and show the impeller and fluid flow direction?     Answer click here
  20. What are main uses of volute in a centrifugal pump? Answer click here
  21. Definition of NPSH?    Answer click here
  22. Why cavitation will occur in Centrifugal Pumps?. why not in displacement pumps?    Answer
  23. NPSH calculation for suction lift?    Answer
  24. NPSH calculation for suction Head?    Answer
  25. Determine whether cavitation will occur in the following condition or not? Water at 70 C ,Datum height 5 m (for suction lift condition), & tank is exposed to atm.    Answer
  26. Write force bance on rotameter float and write advantages and disadvantages? Answer
  27. Units of viscosity?    Answer click here
  28. Difference between Kinematic viscosity and dynamic viscosity?    Answer
  29. Write the forces acting on particle falling in fluid?    Answer
  30. How to write particle Nre?    Answer
  31. How to calculate particle diameter?    Answer
  32. What is minimum fluidization velocity?    Answer
  33. How to calculate minimum fluidization velocity?    Answer
  34. What is the Driving force for Mass Transfer?    Answer click here
  35. What is the Difference between partial condenser and total condenser?    Answer
  36.  If column Delta P decreases what happens to the purity?(In this case it is assumed that bottom pressure is constant)    Answer
  37. What is the Driving force for Evaporation?    Answer
  38. In which column  Delta P is high ?(Packed column or tray column)    Answer
  39. When we will choose packed column?    Answer
  40. What is minimum reflux ratio?    Answer
  41. How to calculate minimum reflux ratio?    Answer
  42. Draw the x-y diagram?    Answer
  43. Explain Me cab thiele method?    Answer
  44. Why reaction will takes place?    Answer click here
  45. C + O2 ---------- CO2 when this reaction is feasible?    Answer click here
  46. What are the differences between MFR and PFR?    Answer
  47. Write the performance equations for MFR, PFR and Batch Reactors?    Answer
  48. A ---k1--- R---k2---- S for the above reaction draw the selectivity diagram when k1 greater than  k2 and k1 less than k2?    Answer
  49. How to find out the order of the reaction?    Answer
  50. A-------R is a nth order reaction. For above reaction how to select a reactor type? and which reactor will give more conversion for same volume of the reactor?    Answer
  51. How to calculate the reactor volume using graphical method for MFR and PFR?    Answer
  52. What is the driving force for Heat Transfer?    Answer click here
  53. Classification of heat exchangers?    Answer
  54. Draw 1-1 Heat Exchanger?    Answer click here
  55. Draw 1-2 Heat Exchanger?     Answer click here
  56. Which Heat Exchanger is efficient 1-1 or 1-2? and Why?    Answer
  57. In a 1-1 Heat exchanger shell side fluid is steam at 100 C and it is leaving as water at 100C which flow pattern will give more Heat transfer? and why?    Answer
  58.  How to calculate U(Overall heat transfer coefficient)?    Answer
  59. Draw the temperature profiles for 1-1 heat exchanger in parallel and counter flow conditions?    Answer click here
  60. Why Don't we use odd number of tube passes in  Shell and Tube Heat Exchanger? Answer click here
  61. What is the difference between DCS and PLC? Answer click here
  50. For the given problem below find the rate of change of 'h' w.r.t 't' using appropriate   assumptions? Answer click here


Q: Where does the head gets developed in a centrifugal compressors?

Q: What is pressure ratio of a compressor:
Q: What sort of bearings are used for high speed compressors?

Q: In what services centrifugal compressors are used? Answer
Q: How reliable are centrifugal compressors?
Q: In what services barrel compressors are used?
Q: What are side-stream compressors?
Q: How the compressors are sealed?
Q: What type of seals are used for air compressor?
Q: Whether online cleaning is used for compressors?
Q: Can centrifugal compressors tolerate high molecular weight fluctuations?
Q: What is surging?
Q: How is surging harmful?

Q: What type of seals are more reliable in hazardous services?
Q: What should be the seal configurations in hydrocarbon services?
Q: How does on identify seal leakage?
Q: What are compressor protections?
Q: Are liquids in the process detrimental to compressors?
Q: What is turndown?


1.Does excessive amount of air at the pump suction cause cavitation? Answer

2.Can a gear pump "lift" liquid? What is dry lift? Answer

3.What determines number of stages of the progressing cavity pumps? Answer

4. Is it true that if centrifugal pump runs in reverse, it will generate zero head? Answer

5. "How Does Pump Suction Limit the Flow?" Answer

6. Please discuss how pumping water differs from pumping 40% Propylene Glycol. Does the impeller have to change trim to produce the same flow and head with a more viscous solution?  Answer
7.  What is the effect of the degree of saturation of dissolved gasses on NPSH? 
Compare 100 deg F deaerated water in a tank with a bladder pressured to 10 psig with a tank without a bladder for the same temperature and pressure, with the pressure provided by, say, a nitrogen bottle causing the water to be saturated with nitrogen. Answer

8. Explain about
1)backward curved blades
2)forward curved blades
3)comparison of above
4)which is more advantageous and why? Answer