New Understand

8/13/2019 New Understand

1/54

1. HSD using the hydrocyclon to pre-separation of liquid:

2. Choice least

3. H2S pressure partial

Standard on NACE: 0.3 kPaA H2S partial. In TLDD project well 7P, H2S partial = 0.646 kPaA > NACE: 0.3 kPaA

So that, they combined well 7 with non-H2S well, H2S total is 0.044 kPa < NACE standard.

And they can using Carbon steel (H2S


2/54

9. Well Unloading Line: to be provide from test header to close drain which can be used during initial start-up

10. TIA must be located Min 2000mm from Choke valve to minimmize temperature efffect

11. Vessel or equipment have minimum temperature so low, it's connect with a short good materia(SS)l by flang

So that, Good material (SS) must minimum 5m from equipment to other material ( ref to P&ID 1066 of TLDD pro

12. On PSV:

Liquid: Velocity Head of downstream PSV must be at 10% Design Pressure or smaller Overpressure.

Pressure Drop on Suction Head must be < 3% inlet pressure.

13. Choice the separator depend on mass flow, turndown(Max flow/minimum flow)

14.Min Flow in Pump

All of centrifugate pump have the Min Flow system(may be PSV as back flow) or Min flow with RO & Ball valve.Purpose: It's protect the pump that on case the block outlet the discharge pump. RO + Ball valve is the system w

15. Explanation the why Crude Heater Outlet isn't using NACE material ( TLDD):

Because, Crude Heater is collection all of wellhead production, so that, total H2S vapour pressure composion < 3

Then, TLDD will be shutdown all of wellhead ( signal is based on AIA on Pig launcher near production pipeline)

16. PSV coefficient of discharge

API 526 using factor = 0.7 to 0.75 based on the actual flow area(NB-18)

Pilot valve available the factor = 0.95 + range range based on the actual flow area

ASME VIII (ASME BPVC) are 90% of the observed values (chapter 3.6.3 "Pressure relief and effluent handling pre

Noncertified valves design for ASME VIII service can have observice coefficientsas high as 0.85.

So that, generally availabe in only a few small sizes, with threaded connection.

17. Insulation Kit (piping)It's special Item on P&ID, so using on break material(interface of two different material that can corrosions). exa

CS & SS. IT's using gasket to avoid direct contact between flanges & sleeve & washer to avoid contact direct

bulong to flange.


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18. Filter Coalescer

Choice the filter coalescer:

If an organic dispersed phase 'wets' organic that is plastic or polimeric hydrophilic ( like water) (oil is contino

Else an aqueous dispersed phase preferably wet inorganic media, such as metal & glass (like oil)

Coalescer work better in laminar flow; increse contcting time wire mesh & streamline

Velocity so high overcom surface tension forces and strip droplets out of the coalescer medium

19. All of well is order Miocene type have to sand detector. Because, Miocene is lower water deep and contain

20. PCS will be control the test well flowline (each of well at a time) based on sequence.

21. On bypass PSV always have a lock close (ball valve), to assure that the operator inadvertent opening th by22. Standard for deflector vessel:


4/54

(ref. 236 page-Pressure Vessel Design Manual

23. Follow the Pipieline: DNV F101 cerfify that with all of pipeline >= 8 in, wall thickness minimum = 12 mm.

24. Follow the Pipeline : DNV F101 certify that with all lining(cladding) thickness must be not less 2.5 mm. (C-400

25. Follow the Pipeline: DNV F101 certify that "clad" if the bond between base and ladding material is metallurgi

and "lined" if bond is mechanical. ( Page 51)

26. Fracture toughness testing of the Base material(BM) and the Weld Metal(WM) welded linepipe, shall be conas part as qualification (Table 6-12, table 6-13). The measured fracture toughness of the BM and the VM shall, as

Have CTOD value of 20 mm, when tested at the minimum design temperature. The testing shall be performed in

Appendix B A 800. Testing is not required for pipes with tnom


5/54

flame mixed.

39. ASME 8 Liquid relief valve: any liquid pressure relief valve shall used at least NPS 1/2 (DN 15)

40. Bypass valve using to :

Prevent working at shut-off point: head is maximum and zero flow rate through valve

Using in boiler-feed, It can decrease the temperature which raise because friction.

Example:

When you increase the orifice (control valve), Q will be increase and H is decrease

From this formula, H is decrease then delta T is decrease

41. Flare: The LPG or fuel gas shall be used to purge the flare headers during start-up.

42. Flow Assurance (No touch time): No touch time may be smaller the shutdown time

Example: When you shutdown pipeline in 6 hr, the 3 hr from initial is not formation the WAT

there for, operator can not touch any thing to system (No touch time) but, after 3 hr, WAX is formatiom

It's not the no touch time.

43. Corrosion protection: Methanol & MEG can prevent the corrosion, and MeOH will prevent corrosion better

but, MeOH shall be using at < 60oC, because above 60oC MeOH is evaporated and is not enough the MeOH liqui

to protecting the system

44. Flow Assurance: Type of slug

1) Hydrodynamic: It's slug in horizontal pipeline(not change the elevation), cause of gas velocity muc

2) Terrain Slug: Is slug formation because the changing of elevation or dip

3) Severe Slug (Based of Riser Slug) is slug formation cause of circummulate at based on riser


6/54

Riser Slug (P.782)

45. Way to Eliminate severe slug:

1) Pipeline route slopes up to the base on of the riser

2) Gas injection into the base of the riser continually lifts liquid out of the riser, preventing the built-u

Noted: why increase the gas at base on riser can prevent the slug?

If gas mass flow rate is inscrease then Vsg is inscrease and Vsg/Vsl is insecrease sao that LHS > RHS a

3) Choking

A fourth method is to install a control valve on the top of the riser. On shutting this valve

a position is reached whereby the frictional pressure drop across the valve acts to stabilize

the gas-liquid flow up the riser. Any acceleration of liquid up the riser due to a decrease

in liquid head in the riser (caused, say, by a gas bubble entering the base of the riser), is

counteracted by the increase in frictional pressure drop across the valve as the liquid

accelerates. The penalty of this way of eliminating severe slugging is that the pressure

drop across the valve will be of the order of a riser height of liquid, thus imposing a

significant extra back-pressure on the system at all times.

46) Slug Catcher

A preliminary design approach was used to estimate the slug catcher size based on the flexibleriser volumes. It was assumed the slug catcher was designed to contain 60% of the liquid in both

By assuming that 60% of this total liquid will fill up 100% of the slug catcher volume

47) Flow Assurance: Turn-Down Case:

The main purpose of this study is to identify the minimum turn down rate required

to achieve a minimum fluid arrival temperature higher than the pour point temperature

Turdown rate may be take of 30 - 90% normal flow rate (so important with oil fluid)

48) Flow Assurance: Ramp-up Case

Purpose of this study was to investigate the liquid surge associate with this operation

Ram-up will be simulation were 'restart' from the previous turndown runs of 25%

Model: ramup from 25% - 100% in 20s.

49) Insulation Pipeline: why is not use the Poly ethane for pipeline insulation:

Polyethylene (PE or HDPE) can handle temperatures up to 80 Celsius and is often used in

direct burial and long term submerged applications for industrial and telephone applications.

Advantages: Very low water absorption and good resistance to a wide range of chemicals

Disadvantages: Very stiff in cold weather and not as resistant to abrasion as polyurethane

Recommended use: Permanent installations, unless high temperature or high contamination

is involved.

50) Table material properties to choice


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51) Flow Asurance: Shutdown

Purpose to investigate the time to reach the pourpoint temperature of the fluid

Model: Flow rate shall be decreased from 100% to no flow in 20s by using a vlave

Noted two case: shutdown for depressure and shutdown for blowdown (refer Bien Dong Flow Assura

52) Flow Assurance: Restart Case

Purpose to investigate the liquid surge associate with this operation

Model: Open valve quikly about 20s

Noted: usually initial properties from shutdown case.

53) Flow Assurance: "What's "near horizontal" and near vertical"

The term "near horizontal" is used in this guide to denote angles of -10 degrees to + 10 degrees from

The term "near vertical" is used in this guide to denote upward inclined pipes with angles from 75 to

54) Flow Assurance: Correct method applicate for FA Model

Chara

Vertical two phase flow, region low, intermediate and hi

Method

Dun & Ros (D-R)

Orkiszewski (OR)

Two Phase flow pressure drop in vertical pipe, this metho

pressure drop in flowing and gas lift


8/54

Extension of Begg & Brill Original with no-slip holdup, the

55) Flow Assurance: Choice the model

1

2

AGA & Flanigan (AGA)

Oliemans (OL)

Gray (GR)

Xiao (XI)

Begg & Brill Revised (B-BR)

Mukherjee & Brill (M-B)

Govier, Aziz & Fogarasi (G-A)

OLGAS-89,92 (O-89, O-92)

Ansari (AN)

Researching in small diameter vertical conduits, study flo

flowrate, gas liquid ratio.

Study two phase in horizontal and inclined pipe. The mod

of up to +/-90

BJA for Condensate (BJ)

Hagedorn & Brown (H-B)

Begg & Brill Original (B-BO)

Well of the method study of pressure drop in two phase i

Developed following a study of pressure drop in wells proResearching from SINTEF laborary with operation conditi

Operating pressure: 20 and 90 barg, gas velocity 13 m/s,

were studied in addion upwards and downward a hill sec

Develop as part of the Tulsa University Fluid Flow Project

partterns for upward two phase flow. Small diameter/ lo

Behavior by experimental, It's good method for near hori

Reasonbly good predictions of the various flow regime tr

each revision in near vertical flow

This correlation was developed by H. E. Gray of Shell Oil

which are predominantly gas phase. Flow is treated as sin

pipe wall. It is considered applicable for vertical flow cas

3 , the condensate ratio is below 50 bbl/mmscf, and t

The Xiao comprehensive mechanistic model was deveprogram. It was developed for gas-liquid two-phase fl

pipelines. The data bank included large diameter field dat

pipeline data bank, and laboratory data published in liter

and compositional fluid systems. A new correlation was p

friction factor under stratified flow. Small diameter/low p

Baker Jardine & Associates have developed a correlat

with a no-slip liquid volume fraction of lower than 0.1. M

The AGA & Flanigan correlation was developed for horizo

The Taitel Dukler flow regime map is used which consider

intermittent, annular dispersed liquid, and dispersed bu

The Oliemans correlation was developed following th

pipelines. The model was based on a limited amount

operating at pressures of 100 barg or higher.

Taitel-Dukler

Taitel and al (Aviv) Barnea

Noted

1. Ussually

2. Normal

3. Not much

Near Horizontal Low Gas-Oil Ratio

Pressure Drop

Near Horizontal Gas/condensate

Begg & Brill

Eaton-Oileman is good

All of method are poor


9/54

3 Both Gray and Hagedo

4

5

6

1

2

3

4

5

6

1

2

56) Flow Assurance standard: Pressure drop:

For plant piping: 0.2 - 0.5 / 100 ft

For gas/condensate pipeline: 10 - 20 psi / mile

Noted: Pipephase 6.02 does not properly account for acceleration losses and is not suitable for use in

57) Flow Assurance: Distinguish the tyype of fluid

Wet gas: Gravity: 40 - 60 oAPI, GORs more than 50000 SCF/STB

Retrograde Gas: Gravity : 40 - 60 API, GORs 3300 SCF/STB to 150000 SCF/S

Volatile Oils: Gravity: 40 API or higher, GOR = 2000 to 3000 SCF/STB

Black Oils: Gravity below 45 API, GOR < 2000 SCF/STB

58) Flow Assurance: Assumed heat transfer cofficient for subsea flowline ( follow chevron)

Nonburied Pipeline without concrete

Application

Hagedorn and Brown i

Nothing is good; Begg

Liquid Hold-up

All available methods

correlation is better th

Near Horizontal Gas/Condensate Lines

Beggs and Brill (Moody

lines nothing is accurat

If gas velocities are hi

use Beggs and Brill (M

careful because the ho

factor of 10 in error in

Inclined Up

Everything is poor. U

(Moody), but answers

Inclined Down and Vertical Down

2Wells

Risers

Buried Pipelines

Concrete Coated Nonburied Pipelines

5-10

Everything is poor. U

(Moody), but answersInclined Down and Vertical Down

Inclined Up

Near Vertical Gas/Oil

Near Vertical gas/condensate

U-value BTU/hr/ft2/degF

20-40

1-3

3-5

Flow Regime

The Taitel-Dukler flow regime map is as good as OLGAS for near horizontal f

of the slug-dispersed bubble boundary. This boundary is very poorly predicted. I

it is recommended that a value of ~10 ft/sec be used as the superficial liquid vel

bubble transition rather than the Taitel-Dukler prediction.

The Taitel-Dukler-Barnea map for near vertical flow is also as accurate as

Near Vertical Gas/Oil

Near Horizontal Low Gas-Oil Ratio Beggs and Brill (Moody

The most accurate me

Hagedorn and Brown i

Near Vertical Gas/Condensate


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59) Properties defend the pressure & temperature

Gas

Temperature

Oil

Temperature


11/54

60 Flow Assurance: Why dehydrate on platform PQP ???

Notice: HYDRATE FORMATION TEMPERATURE SHALL BE DECREASE (MAY BE NEGATIVE) FOLLOWING THE WA

example:

Because this, dependent the lowest temperature pipeline (operating: shutdown, restart, blowdown,depressure

and request the treatment the dehydrate zone.

Reference Bien Dong PQP platform:


12/54

61. Sonic velocity in multiphase

- Sonic velocity in multiphase always lower than single phase, experimental: Vsonic = 30 - 40 m/s in 0.

62. Flow Assurance: Criterion pigging (when we shall be pigging?)

When wax thickness = 2 - 3 mm or loss of 4- 6 mm then need to pigging ( NTNU- wax deposition Models - Maste

63. Flow Assurance: Avoid compromising pig selectio and operation

1. Pipe: - Constant bore if can

- Maximum diameter pipe deviation and Any internal diameter chan

2. Valve: - Valve always full bore and concentric with pipe3.Tee/Offtakes - Branch connection > 50% internal pipe should be barred

- Branch have to installate above centerline to avoid deposit being pu

4. Bend - Minimum bend radius

64. Flow Assurance: How is stability flow in flow as, defined in exit of flow line

stability index = (max liquid flow - min liquid flow)

average liquid flow

65 Insulation: SPU properties refer to ASTM C518

66. Corrosion: Rul of Thumb for CO2 corrosion:


13/54

C.de Waard and D.E.Milliams give a rule of Thumb, if CO2 pressure partial > 2 bar then CO2 corrosion

CO2 pressure < 0.5 (7 psia) bar, CO2 corrosion can acceptable.

67. Vent Flare system: Probleme, closed drain vessel is handle blowdown and relief flowrate so that gas outlet c

Probleme: How many liquid that permit to drawn-out by gas? (kg/h, m3/s)?

PTS 80.45.10.10 only handle dry gas in vent stack. But can permission gas load () is < 0.07

68. Slope line from drum vessel to flare:

PTS 80.45.10.10 page 46 refer slope 1:200 to 1:500 for correct slope in flare.

69. Flow Assurance Liquid hol-up to liquid inventory system

From GPSA 17 chapter (Eq. 17.57): IL= 28,58. H le.d2.Lm

Lm: Length of line (miles)

d: internal diameter of pipe, inch.

70. Flare system:Velocity at vent tips is enough high to jet gas entrain by air (API 521-2007 page 66)
http://localhost/var/www/apps/conversion/tmp/nghia/A.%20Phuong/A.%20Phuong/Petronas%20standard/PTS_D&Ec/80451010.pdfhttp://localhost/var/www/apps/conversion/tmp/nghia/A.%20Phuong/A.%20Phuong/Petronas%20standard/PTS_D&Ec/80451010.pdfhttp://localhost/var/www/apps/conversion/tmp/nghia/A.%20Phuong/A.%20Phuong/Petronas%20standard/PTS_D&Ec/80451010.pdfhttp://localhost/var/www/apps/conversion/tmp/nghia/A.%20Phuong/A.%20Phuong/Petronas%20standard/PTS_D&Ec/80451010.pdf


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80. Flare system: (Velocity at tips): Max. velocity at the tip should not exceed a Mach 0.5 but velocity existing fla

81. Flare: Pressure drop: Pressure drop in flare usually = 0.2 bar, minimum pressure at flare not smaller 0.7 bar (

82. Wax consider: Rule of thumb heavy oil is considered all liquid petroleum which has API gravity betw

83. Flow Assurance standard for water contents in pipeline in sale gas: 7 lb H2O/MMscf, refer "sai ..\Flow As

84. Important worst-case in flow assurance:

Maximum liquid hold-up in pipeline: Higher pressure, lower temperature, low flow.

Pigging: Worst-case at high liquid hold-up in pipeline. (MT take of low flow, low temperature (at low

Hydrate: Worst-case at high pressure ( affect much to hydrate form)

85. Flow assurance: Relationship between pressure drop, velocity & flow rate

Not correct when thinking that: If you decrease flowrate(or increase size of pipe) then will be decrea

Because: Pressure drop = friction loss (velocity) + Block of liquid hold-up, when decrease flowrate so

If loss of liquid hold-up > benefit of friction loss then pressure will be decrease.

86. Purge Flare

Flare have to continuously by process fluid (may be extract from flare header) to keep always exites

A check vale is require when inert gas is used as purge gas

83. HTGC (High temperature gas chromatography) & SFC (supercritical fluid chromatography): A method in labor

carbon atoms.
http://localhost/var/www/apps/conversion/tmp/pipeline/Wax/FA%20and%20sour%20gas%20in%20natural%20gas%20production.pdfhttp://localhost/var/www/apps/conversion/tmp/Flow%20Assurance/Hydrate/Saied-Handbook-of-Natural-Gas-Transmission-Processing.pdfhttp://localhost/var/www/apps/conversion/tmp/Flow%20Assurance/Hydrate/Saied-Handbook-of-Natural-Gas-Transmission-Processing.pdfhttp://localhost/var/www/apps/conversion/tmp/Flow%20Assurance/Hydrate/Saied-Handbook-of-Natural-Gas-Transmission-Processing.pdfhttp://localhost/var/www/apps/conversion/tmp/pipeline/Wax/FA%20and%20sour%20gas%20in%20natural%20gas%20production.pdf


15/54

= 99 barg. So, It's boundary of the class 600#.DD choice class 900# for safety.

of not requiring the ESD

pressure. In output(running of pig piping ) is drop pressure and temperature

WHP) will WAT formation. Need the evacuated/drain to eliminated the


16/54

e. But to fall the cost, It's connect this pipe with other material (CS)

ect)

hich choose in TLDD project due to cheaper than PSV.

kPa, not using NACE. But if each of well is failure and H2S greater 3kPa

sure)

mple


17/54

ustly phase)

larger sand quantity.

pass( throwing continuose the HC to flare or environment)


18/54

Book)

or pagd 51)

cal &

ucteda minimum,

according

C (Flow Assurance Deepwater 7-15)

peline may be take longer.

dent of the downstream pressure (Flow Assurance Deepwater 8-9)

system.

effect so much to heat)

and can assume = wall temp.

ll sao that fluid temp. is decreased to minimum ambient so

e to 0.5 ratio 2 for exactly simulaion (but not obligate)


19/54

EG

d

greater than liquid and formation slug


20/54

p of liquid and subsequent seal to the gas flow

d decrease or preventing the severe slugging


21/54

nce)

horizontal.

+ 90 degrees from horizontal.

teristic of Method

h gas throughputs respective

d can accuracy 10% two phase

Sequence for using

3

2


22/54

friction factor is changed from standard smooth pipe model

1", 1.25", 1.5" nominal size with varying liquid, gas

el inclines flow both upwards and downwardsat angle

nclined flow

ducing gas and condensate, GOR = 3900 - 1170000 scf/bbln is similar field conditions, test 800 m long pipe and 8" DN

liquid velocity up to 4 m/s, inclination angle between +-1

ion ahead of a 50 m high vertical riser. Accuracy is likely Taitel

(TUFTP), model of flow characteristics of predicted flow

pressure good for near vertical.

izontal (only near horizontal)

nsitions, and the accuracy of the predictiona has improved with

ompany for vertical flow in gas and condensate systems

gle phase, and water or condensate is assumed to adhere to the

es where the velocity is below 50 ft/s, the tube size is below

he water ratio is below 5 bbl/mmscf.

loped as part of the TUFPP researchow in horizontal and near horizontal

a culled from the AGA multiphase

ture. Data included both black oil

roposed which predicts the internal

ressure data

ion for two phase flow in gas - condensate pipelines

ethod is similar Oil-man

ntal and inclined two phase flow of gas-condensate systems.

s five flow regimes, stratified smooth, stratified wavy,

bble.

study of large diameter condensate

of data from a 30", 100 km pipeline

3

1

1

3

3

1

3

3

2

2

3

2

1

1

ethod

(Moody) is good)

for relative high velocity.

for low velocity


23/54

rn-Brown are good.

flare system design as a result

B

s good

and Brill (Moody) is fair.

are poor.The Eaton holdup

an the other methods.

) is usable for low GOR

e for gas/condensate

h, use no-slip; otherwise

ody). The user must be

ldups can be a

some cases.se Beggs and Brill

may be suspect.

se Beggs and Brill

may be suspect at times.

low with the exception

this method is used

city for the slug-dispersed

LGAS.

) is O.K.

hod is no-slip.

pretty good.


24/54

Pressure

Pressure


25/54

ER CONTENT IN FLUID

), engineer will be analysys water content in fluid flow in pipeline


26/54

- 0.8 void fraction at 1.4 - 1.6 bar

thesis)

e should be made within a transition piece of 1:5 slope.

hed in branch.


27/54

will be serious

n carry the liquid to vent amospheric (liquid carry-over)

.


28/54

re do not exceed a Mach No. 0.7

inimum).

een 10 - 21.9 and extra-heavy oil less than 10oAPI (Berberii, 1998) (page 9)

urance\Hydrate\Saied-Handbook-of-Natural-Gas-Transmission-Processing.pdf

and high pressure)

e velocity and decrease pressure drop. SO FAULT

riction loss decrease but pressure loss for liquid-holdup inscrease

as in flare to avoid exploration by air enter flare system.

ary define WAX contents, It enable identification of wax up to 100


29/54


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Check P&ID

Open drain tank:

Heat tracing pipe

Electrical heat on bottom open drain tank to prevent WAX

Have over flow and vent pipe. Vent pipe ensure that free gas/air into open drain

Rodding point to supply to removal of blockages

2. Sand probeThis is equipment to monitor the erosion found in process systems, in oil & gas sand probe using to mo

The distance from chocked valve to sand prob

3. Flow straighteners (conditioners)

Flow straighteners eliminate rotation of fluids and steady velocity profile of fluid flow, enable to shorte

standard. Individual types of flow straighteners differs by construction design ( Zanker" perforated til

square sections, Etoile" 8 radial lamellas arranged in the star-shape) and its use. Use of flow straight


41/54

LINK: https://docs.google.com/viewer?a=v&q=cache:tEngwITn1msJ:www.onicon.com/pdfs/0497-

3_Flow_Straightener_Catalog_Sheet_0112.pdf+flow+straightener&hl=en&gl=vn&pid=bl&srcid=ADGEES

YOQWCaWM82oNJW9yiJfn1gmd_tJLcDGm_yoHBenFbhX-6KxVr9BHHaaVEz3vq7lVo4a5XcBLI&sig=AHIE


42/54

Rodding (tm che lc cn bn)

itor erodes of sand in oil

e is min 2 ft (610 mm) (ANZ P&ID note)

length of inlet piping in front of primary element, especially behind adapting pipes not stated in the

le+bundle of channels, Sprenkle" 3 perforated tiles, bundle of pipes, AMCA seam of channels of

ner helps to achieve higher stability and accuracy of measured flow.


43/54

jX2NZgXKbuTkgpSqxfz6Xtvx7iRjjXjsyniXU6p7pMptWkkttKNHwGFskwBH-

bQSMe4WBFi5RkZRaJOWVOSTbopOeA


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1. Hp th: nh hng dung mi n qu trnh hp thCng nng cht b hp th yu cu t c, nu lng dung mi tng ln th gim c kch thc

Nu gim lng dung mi i hi din tch tip xc hai pha (kh v dung mi) nhiu hn hay kch thc

C th quan h bi phng trnh sau:

G = Ky.F.Ytb (l phng trnh truyn cht c bn)

Ky: h s chuyn khi tnh theo pha kh, Ky s khng i nu nhit v p sut khng i,

Ytb: l ng lc trung bnh ca qu trnh.

y = 1/Ry: h s cp khi ca qu trnh, Ry l tr lc trong pha y (pha kh)

m: h s phn b nng , m = /P (: l hng s henry) Pi = xi

Nu cu t d ha tan th m/x rt nh Ky = y

Nu cu t kh ha tan th m/x rt nh Ky = x

ng lc trung bnh logarit

Thay i ng lm vic khi thay i ng lc trung bnh ca qu trnh

BA4 di nht nn ng vi ng ng lc cn bng nh nhtV G v Ky k i nn F.Ytb khng i, do BA ng vi F nh nht v ng lc trung bnh l

BA4 nh nht nn F(din tch tip xc) ln nht

M A = Gtr/Gx, B = Yc - (Gx/Gtr).Xd

Gtr : lng kh tr khng i

Gx: lng dung mi vo thit b hp th

Phng trnh ng lm vic hp th: Y = AX + B

Do , BA4 nghing nht 9(gc nh nht) nn Gx: lng dung mi nh nht

BA c gc nghing ln nht lng dung mi ln nht


45/54

Kt lun chn dung mi:

Dung mi t thit b ln, dung mi nhiu thit b nh gn

2.Hp th: nh hng ca nhit v p sut n hp th

nhit tng th h s henry tng (phng trnh henry) do cn bng chuyn dch v pha trc tung

ng AB s khng i(ng lm vic ph thuc thnh phn kh, lng dung mi v din tch tip xc

ng cn bng ph thuc p sut nhit )

Nu nhit cng tng,ng lc qu trnh cng gim n t3 ct ng lm vic s khng th hp th

Do nhit cao xu cho qu trnh, tuy nhin nhit 1 khong no y li c li v ma st gim n

p sut tng lm m gim ( m = /P) ng cn bng di chuyn v pha trc honh hayNhng p sut tng s km tng nhit nh hng xu n qu trnh nn p sut cao ch dng h c

Kt lun: Hp th tt p sut cao v nhit thp(cho php), l nguyn nhn ngi ta mong m

Qu trnh hp th l s ha tan nn c s sn sinh nhit


46/54

thit b

s ln hn

hi ng lc khuych tn, thm thu qua mng tip xc s k i)

Pi= xi

n nht


47/54

Tt nht v c th t nng Yc thp hn (hay dng kh tinh khit hn)

)

c (k th t c Xc) nng cui.

n tng d khuych tn.

ng lc qu trnh tng hp th tth kh ha tan CO2, CO

n lu cht vo thp hp th nhit im sng (dewpoint)


48/54

Number

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

1819

20

21

22

23

24

25

26

27

28

29

30

Flow assurance (

WAT deposit)

General

Corrosion

Corrosion

Corrosion

Cathodic reactionPosition terminal(cc dng): where electron flow to, and redu

+ 4H+4e-= 2H2O ( if environment is acide base)

ion strength

The ionic strength of a solution is total of the concentration of inumber of ion. Exa.: Ionic strength of a mixed 0.050 mol d

I = 1/2((2 (+1)2 0.050) + (+1)2 0.020 + (

shear rate

The velocity gradient measured across the diameter of a fluid-f

change of velocity at which one layer of fluid passes over an ad

parallel plates that are 1.0 cm apart, the upper plate moving at

lower plate is not moving and the layer nearest the top plate is

cm/sec. The velocity gradient is the rate of change of velocity w

gradient with shear rate (v1 - v2)/h = shear rate = (cm/sec)/(cm

FluxIt's abbracation to taking that a unit (mass, heat) tranfer a un

capacity of diffusion of mass tranfer on 1m2on 1 second. D: diff

Anodic reaction Negative terminal(cc m): where electron flow from, and oxi

Title Abbrevation

porosityFlow assurance The concentration of oil in a wax deposit, oile in 3D-deposit ( Fi


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2 BASIC THEORY OF GROUNDWATER FLOW

2.1 Introduction and terminology

Three types of aquifers are considered (see Fig. 2-1):

- the confined aquifer, confined at top and bottom by impervious layer

- the unconfined or phreatic aquifer, which has a free water table, and

- the semi-confined or leaky aquifer, which is receiving water from or losing water to

overlying or underlying aquifers through a slightly pervious top or bottom boundary

2.2 Darcy law

(2-1)

(2-2)

The true pore velocity can be obtained by dividing the Darcy flux with the porosity n of the soil medium

(2-3)

Flow in subsurface waters can be divided into unsaturated and saturated flow. The unsaturated flow is

Chapter 2 regional groundwater flow is discussed. Regional implies that we are interested in aquifers or

much larger than their depth. Moreover, we consider porous aquifers only, as opposed to fracrured-roc

The variable to be calculated in the models is the piezometer head in the cases of confined and leaky

aquifer and the water table elevation in the case of unconfined aquifer. For both variables the term

head (H) or hydraulic head is used throughout the book. Flow is caused by gradients of the head.

In confined aquifers we usually utilize the concept of transmissivity which is the product of hydraulic

conductivity K and the aquifer thickness b, i.e. T = Kb and its unit is usually m2 d-1. Transmissivity is

discussed in detail in Chapter 3.

By a series of sand column experiments Henry Darcy established in 1850's that, for a given type of

sand, the volume of discharge rate Q (m3 s-1)is proportional to the head difference DH and to the cross-

sectional area A (m2) of the column, but is is inversely proportional to the distance DL of the flow path.

Discharge Q can be calculated as

where the proportionality coefficient K (m s-1

) is called the hydraulic conductivity of the soil. The

average flux can be obtained by dividing Q with A. This flux is often called Darcy flux qW:


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Eq. (2-3) implies that the true velocity of the water molecules is larger that the average velocity becaus

Negative sign in Darcy's law?

The reason for the negative sign in Eqs. (2-1) or (2-2) is that water is flowing from higher to lower poten

Similarity between Darcy's law and other laws of physics

It is important to recognize the similarity between Darcy's law, Fourier's law of heat

transfer and Fick's law of diffusion flow.

Fourier qH= -K H DT/Dz

where qHis thermal flux (J m-2

s-1

) across a plate, KHis thermal conductivity of the plate (J m-1

K-1

s-1

), DT

Fick's law qC= -D DC/Dx

where qCis the diffusive flux (mol m-2

s-1

), D is diffusion coefficient (m2s

-1), DC is

concentration difference (mol m-3

) between two points located at a distance Dx (m)

from each other.

Similarity between Darcy's law and other laws of physics

It is important to recognize the similarity between Darcy's law, Fourier's law of heat

transfer and Fick's law of diffusion flow.

Fourier qH= -K H DT/Dz

where qHis thermal flux (J m-2

s-1

) across a plate, KHis thermal conductivity of the plate (J m-1

K-1

s-1

), DT

Fick's law qC= -D DC/Dx

where qCis the diffusive flux (mol m-2

s-1

), D is diffusion coefficient (m2s

-1), DC is

concentration difference (mol m-3

) between two points located at a distance Dx (m)

from each other.

2.3 Dupuit-Forcheimer assumption


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In the regional groundwater models it is assumed that flow is essentially horizontal which implies that d

Dupuit or Dupuit-Forcheimer-assumption. This is not true in the vicinity of e.g. pumping wells, in region

aquifer thickness, in the vicinity of infiltrating surface water bodies, and in regions of strong groundwat

vertical disturbancies, however, will usually become negligible over a horizontal distance of the order o

aquifer thickness (Kinzelbach 1984).


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.

iscussed in Chapter 7 and therefore, in

parts of aquifers with horizontal extensions

k or karst aquifers.


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only the pore volume contributes to flow.

tial, i.e. the direction of flow has the opposite sign as compared with the potential gradient.

is temperature difference (K) and Dz is the thickness of the plate (m).

is temperature difference (K) and Dz is the thickness of the plate (m).


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H/dz = 0. This is called

s with strongly varying

r recharge. These

magnitude of the

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