some questions ogp1

8/8/2019 Some Questions Ogp1

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Some questions

1.

If a separator having a separation co-efficient of 0.389 were to separateliquid droplets of 200 microns from the gas stream in the secondaryseparation section, what will be your estimate of the liquid droplet settlingvelocity if they were to be suspended in the gas stream? The specificgravities of the separated liquid and gas are respectively 0.88 and 0.77.Operating temperature is at standard condition while pressure is 500 psig.

2. In tabular format state two constituents of a typical reservoir fluid and therespective treatment the reservoir fluid will be required to undergo due totheir presence ( water, co2 h2s inert gases, sediments,dehydration/desalting, sweetening, filtration)

3. Explain application of vapour pressure and lvp in liquid stabilization andstorage.

4. The difference between a chiller and evaporator isa. Strictly dependent on the processed or process fluidb. That one is cryogenic while the other is notc. That one is a heat exchange while the other is notd. That there is no difference because both take heat from the process fluid

5. Water dry sale natural gas is defined asa. Natural gas without water b. Natural gas at its water dew pointc. Natural gas containing no more than the required water contentd. All the above


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0F

McKetta and Wehe Correlation Chart


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1. Mention two (2) major groups of products from Gas-to-Liquid Technology and givean example of each product groupLVP NGL LNG, IVP NGL e.g gasoline, HVP NGL e.g LPG

2. Separation is process wherebya. Reservoir fluid is separated into its component phasesb. Crude oil is separated into its component phasesc. Natural gas is separated into its componentsd. Reservoir fluid is separated into its component compounds in a separator.

3. Name five main functions of a typical flow station feeding an Oil Terminal in NigeriaSeparation, pressure reduction ,crude treatment(dehydration and sweetening),testing, waste water treatment.

4. Below is NOT one of the reasons why we remove water from natural gasa. It causes slugging flowb. It increases pipeline transportation loadc. It increases heating value of natural gasd. In conjunction with CO2 and H2S, it causes corrosion

5. Give the reasons why the following are removed from natural gas before liquefactionCompound Reason for Removal

1 CO2 Corrosion, reduce heating value, solidifies bcos of cryogenics

2 Mercury Poisonous to human, equipment and processes

3 Water Corrosion, reduce heating value, enhance hydrate


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formation

1. Complete the simple process flow diagram of the natural gas liquefaction processbelow

Compression, treating, dehydration , precooling and liquefaction/storage.

Name types of crude the phase diagram represents

Pure substances one liqid hc and other gas hc


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B-IX-Stream 4omponent Composition

C1 7.81E-01

C2 9.04E-02C3 1.12E-02n-C4 1.02E-02n-C5 4.10E-03n-C6 1.70E-03C7 1.10E-03

C7+ 1.00E-011.00E+00

Edjeba Stream

retrograde condensate bcos at 90 evenly distributed

Gas well ( likely dry gas)

Briefly describe how a liquid level controller arrests liquid level problems arising inthe separator.

1. Figure XII-1 above represents the phase diagram of Edjeba Stream. Whatis the characterization factor of the Edjeba crude at 3500 psia if its gravityis 36 0F API.


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a. On the basis of this factor alone, what type of crude do you assess this crude tobe?

________________________________________________________ _

b. What is your classification of the reservoir fluid based on the API value ____________________________________________________________

In the separator, bulk of the liquid is separated out of the reservoir fluid ata. Liquid-gas interfaceb. Liquid accumulation sectionc. Primary sectiond. Secondary section

Briefly describe the phase changes the above hydrocarbon system in figure XII-2 will undergo when subjected to an isobaric expansion at 2150 psia from 3800Fto 110 0F.


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How do you refer to the phenomenon that the fluid has undergone in question20 above

21. In the separator, straining vanes are meant toa. Straighten oil dischargeb. Straighten gas dischargec. Guarantee laminar and steady gas flow in the secondary separation

sectiond. Guarantee laminar and steady oil flow in the accumulation section

22. What is your estimated bubble point pressure of a reservoir crude withsurface produced gas-oil ratio of 500 scf/stb? The separated gas and stock tankoil have gravities of 0.7 and 32 API respectively. The reservoir is ascertained tobe at 250 0F

1. Give the functions of the followings in emulsion formation, stability or treatment

No. Item Function

a Emulsifier

bEntrained Water

c Free Water

d Agitation

e Storage Processes


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f Heat

g Chemicals

h High Fluid Pumping Rate

2. Below is a pair of hydrocarbon products from a typical tank farm vapour recovery plant

a. Liquid Vapour and LNGb. LNG and LPGc. LPG and Liquid Vapour d. LPG and Petrol

3. What is the name of the refrigeration system employed in the liquefaction of natural gas at the

Bonny NLNG? ____________________________ propane pre cooled mrcmtd ____________________________________

4. Sketch and label a block diagram of the above refrigeration process ONLY toREFLECT the meaning of the name

5. A well gas stream of 0.85 specific gravity flow 21 mm scf/day at 3100 psig and84 0F to a processing center 47 km away from the well through TransnetPipeline. The processing center equipment are rated at 1000 psig and 350F.

a. What is this gas stream entry temperature into the processing plant at theplant operating pressure ?


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b. If the temperature in 8(a) above is different from the designed processingplant temperature, choose the appropriate and most cost effectiveprocessing equipment to rectify the imbalance and sketch process flowdiagram relating ONLY to your equipment indicating appropriatethermodynamic variables.

c. Will this transportation need any hydrate formation prevention?

d. If the gas were to be dehydrated to 6 lb.H2O/mm.scf with a TEG at theprocessing center, what will be the removal rate of water?.


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Identify the reservoir hydrocarbon fluids that the following phases represent


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Dry Gas, retrograde condensate, wet gas

6. Determine the Bubble point pressure of a newly discovered field whose oilhas 300 API gravity with 0.7 specific gravity gas. The reservoir temperature is1850 F and its gas-oil ratio is 350 scf/stb. Bubble PointPressure:____________________________________

7. How does an increase in temperature affect crude solution gas-oil ratio atconstant pressure. Increase in temperature leads to decrease in GOR atconstant pressure

8. What devices would you employ in the following sections of a typical verticaseparator to ensure effective separation of foaming reservoir fluid

Primary Section Secondary Section Mist Liquid


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Extractor Accumulation

centifuge Plates and baffles vanes Level controller,dump valve and

vortex breaker

9. The separation of tiny liquid particles from gas is mostly effected by.a. Primary separation mechanismb. Gravity settling mechanism.c. Impingement mechanismd. Secondary separation mechanism

10. Equilibrium calculation is employed to Flash Vaporization which occursupon pressure reduction on a confined liquid mixture resulting in gas comingout to occupy discrete region of its own without any contact with the liquid.

a. Falseb. Truec. None of the above

11. Equilibrium calculation is employed to Flash Vaporization which occursupon pressure reduction on a confined liquid mixture resulting in gas comingout to occupy discrete region of its own without any contact with the liquid.

d. Falsee. Truef. None of the above

12. Various shades of liquids from gas are commonly referred to ascondensates. Explain the main reason for this.

Pressure reduction and temperature reduction leading to liquidcondensing out of the gas.


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13. Generally systems energy increase is associated with the systems a. Temperature increase and pressure increaseb. Temperature decrease and pressure increasec. Temperature Increase and pressure decreased. Temperature decrease and pressure decrease

some questions ogp1

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