Use scantron to answer all questions PTRT 2470: Petroleum Data Management 3 - Facilities Test 4 (Spring 2017) 1. The term dehydration of natural gas means A. addition of water vapor B. removal of water vapor C. addition of gas hydrate D. removal of gas hydrate 2. Water content can affect long-distance transmission of natural gas. Which statement is not true? A. Liquid water and natural gas can form hydrates that may plug the pipeline and other equipment B. Natural gas containing CO 2 or H 2 S is corrosive when liquid water is present C. Liquid water in a natural gas pipeline can result in lower flow efficiency of the pipeline D. Water content increases the heating value of natural gas being transported 3. What principle is not applied in dehydration of natural gas? A. cooling B. compression C. reaction D. absorption E. adsorption 4. What is the principle behind dehydration by adsorption? A. distillation B. compression C. reaction D. solid desiccation E. liquid desiccation 5. What is the principle behind dehydration by absorption? A. distillation B. compression C. reaction D. solid desiccation E. liquid desiccation 6. Which is the mostly used glycol for dehydration of natural gas? A. EG B. DEG C. TEG D. T4EG 7. In a typical glycol dehydration plant, where is the inlet gas cleaned of liquid traces before dehydration? A. boiler B. distiller C. scrubber D. contactor E. surge tank The requirements for a trayed type glycol contactor are: Gas flow rate: 11 MMscf/d Gas specific gravity: 0.7 Operating line pressure: 800 psig Gas inlet temperature: 95 o F Outlet gas water content: 5 lb H 2 O/MMscf Design criteria: GWR = 4 gal TEG/lbm H 2 O with 99.5% TEG 8. What is the temperature correction factor C t? A. 0.995 B. 1.00 C. 1.005 D. 1.01 9. What is the corrected gas capacity (MMscf/d) of the contactor? A. 10.89 B. 10.95 C. 11.0 D. 11.06 E. 11.39 10. What is the best diameter for the contactor? A. 18 in B. 24 in C. 30 in D. 36 in 11. What is the water content (lb H 2 O/MMscf ) of the inlet gas? A. 40 B. 48.75 C. 57.5 D. 66.25 E. 75 1
12. What is the temperature (F) of the outlet gas? A. 20 B. 23 C. 28 D. 40 13. How many trays are required? A. 2 B. 3 C. 4 D. 5 E. 6 14. What type of compressor is used to prevent gas lock of sucker rod pump? 15. What type of compressor is used to restore the pressure drop from transportation in pipelines? 16. What type of compressor is used for underground storage of natural gas? 17. What type of compressor is used in stage separation facilities? 18. What facility in a compressor station removes water, hydrocarbons, and other impurities from natural gas? 19. What facility in a compressor station helps to reduce the noise level? 20. What facility in a compressor station is used to maintain pipeline integrity? In a 4 stage compression, the suction pressures at the first and third stage are 100 psi and 1600 psi. Answer the next 3 questions 21. What is the compression ratio per stage? A. 1 B. 2 C. 2.52 D. 4 E. 16 22. The delivery pressure at the fourth stage is A. 3,200 psi B. 4,032 psi C. 6,400 psi D. 16,128 psi E. 25,600 psi 23. What is the overall compression ratio? A. 32 B. 40 C. 64 D. 160 E. 256 24. For a three stage compressor, compressing from suction p1 to suction p2 to suction p3 is with no pressure losses. If p1 and p3 are known, then the intermediate suction pressure p2 is given by A. p2 = (p1 + p3)/2 B. p2 = (p1 p3) C. p2 = p3 (p3/p1) D. p2 = p1 (p3/p1) E. p2 = p1 (p1/p3) 25. In gas compression, the inlet pressure is always the discharge pressure. A. equal to B. less than C. more than 26. In gas compression, the inlet volume is always the discharge volume. A. equal to B. less than C. more than 2
27. Which of these components may not be a part of reciprocation compressor? A. piston B. cylinder C. impeller D. suction valve 28. What type of compressor has a higher mechanical efficiency? A. reciprocating compressor B. centrifugal compressor 29. What type of compressor undergoes adiabatic compression? A. reciprocating compressor B. centrifugal compressor 30. Natural gas is adiabatically compressed in 2 stages with an overall compression ratio of 8 and stage 1 suction temperature of 65 F. Calculate stage 1 discharge temperature assuming z is constant and k=1.3. A. 83 F B. 207 F C. 257 F D. 388 F E. 667 F 31. If no intercooler is used in previous question, what is stage 2 discharge temperature? A. 105 F B. 169 F C. 263 F D. 388 F E. 848 F 32. Intercooling in multi-stage compression is done A. to cool gas at first stage inlet B. to cool gas at final delivery C. to enable compression in two stages D. to minimize the work of compression 33. What type of heat exchanger is shown? A. countercurrent flow B. co-current flow 34. Which of the following gases in natural gas is an acid gas? A. CO 2 B. H 2 O C. He D. N 2 E. all of them 35. Sweetening is the process of removing what gas from natural gas? 36. Which of the following may not be responsible for sweetening solvent losses? A. vaporization B. temperature C. degradation D. mechanical E. viscosity 37. Which of the following may not be an operating problem in a sweetening plant? A. foaming in the contactor B. corrosion C. vaporization of solvent D. degradation of solvent E. good contact of solvent with contactor 38. Which of the following is not a desirable characteristic of a sweetening solvent? A. Hydrocarbons pickup must be low B. Acid gas pickup must be high C. Solvent must be thermally stable D. Solvent losses must be minimized E. Solvent should foam in the contactor 39. Which of these processes cannot be used to remove traces of CO 2 from natural gas? A. iron-sponge B. monoethanoalamine C. hot pot D. glycol/amine E. all 40. Why would water be added to monoethanoalamine in a natural gas sweetening plant? A. to pickup H 2 S B. to pickup CO 2 C. to pickup H 2 O D. to wet the gas for effectiveness 3
41. Which process has difficulty in meeting the H 2 S specification if the H 2 S/CO 2 ratio is high? A. sulfinol B. alkanolamine C. iron-sponge D. glycol/amine E. hot pot 42. Which process has the ability of removing water vapor, H 2 S and CO 2 in the same process? A. sulfinol B. alkanolamine C. iron-sponge D. glycol/amine E. hot pot 43. What is the value of y to balance the following regeneration reaction in a sweetening plant? x Fe 2 S 3 + y O 2 v Fe 2 O 3 + w S A. 1 B. 2 C. 3 D. 4 E. 5 44. What is the value of x to balance the following regeneration reaction in a sweetening plant? x Fe 2 S 3 + y O 2 v Fe 2 O 3 + w S A. 1 B. 2 C. 3 D. 4 E. 5 45. What does methane number of natural gas measure? A. volume B. heating value C. lightness D. load on burner E. dew point 46. What type of gas is dissolved in oil? A. associated gas B. non-associated gas C. solution gas D. gas hydrate E. gas condensate 47. What is the minimum percentage of methane in dry natural gas? A. 5 B. 15 C. 50 D. 85 E. 95 48. Which of the following parameters is not a typical standard sales gas requirement? A. volume B. methane number C. viscosity D. calorific value E. dew point 49. Which of the following is NOT true about odorization of natural gas? A. it gives the gas unpleasant smell B. it enables to detect gas leaks C. it enables to see gas D. it is deliberately added to gas E. sulfur is a good odorant 50. Which of the following cannot be classified as conventional natural gas? A. associated gas B. non-associated gas C. gas condensate D. coal-bed methane 51. Which of the following gases in natural gas can reduce its heating value? 52. Which of the following gases in natural gas can primarily lead to gas hydrate? 53. In which of the following natural gas forms can heptane be mostly found? 54. Which of the following natural gas forms contains mainly methane? 55. Which of the following natural gas forms is referred to as natural gasoline? 4
56. What equipment is needed to remove condensate from natural gas? 57. What equipment is needed to process NGL into purity products? 58. What equipment is needed to produce LNG? 59. In an LNG plant, what is least considered necessary to be removed before the gas is liquefied? A. condensate B. carbon dioxide C. nitrogen D. water vapor E. hydrogen sulfide 60. If 1 scf of natural gas generates 1000 Btu of heat, what is the heating value of 90 MMscf (million standard cubic feet) of the gas in dekatherms? 1 dekatherm = 1,000,000 Btu A. 90 B. 9,000 C. 90,000 D. 900,000 E. 9,000,000 5