MODULE 4

VISCOSITY MEASUREMENT WITH OSTWALD VISCOMETER

PRACTICUM REPORT

Name : Muhamad Choirul Azis

NIM

Group

:

:

12213060

2nd Shift Group 2

Practicum Date : November, 4th 2014

Due Date : November, 18th 2014

Lecturer : Zuher Syihab ST, Ph.D.

Module Assistant : Lambang Tejo Handoko (12211020)

Agung Setiaji (12211053)

Rian Edi Cahyanto (12211057)

LABORATORY OF RESERVOIR FLUID ANALYSIS

MAJOR OF PETROLEUM ENGINEERING

BANDUNG INSTITUTE OF TECHNOLOGY

2014

CONTENTS

CONTENTS........................................................................................................... i

LIST OF TABLES................................................................................................. ii

LIST OF FIGURE.................................................................................................. iii

BAB I PURPOSE OF EXPERIMENT

1.1 Purpose of experiment............................................................. 1

BAB II BASIC THEORY AND PRINCIPLE OF EXPERIMENT

2.1 Basic Theory............................................................................ 1

2.1 Principle of experiment ........................................................... 3

BAB III DATA PROCESSING

3.1 Experimental Data.................................................................... 53.2 Data Processing........................................................................ 5

BAB IV ANALYSIS

4.1 Assumption ............................................................................. 84.2 Practicum Sustainability.......................................................... 84.3 Tool.......................................................................................... 94.4 Result Analysis........................................................................ 10

BAB V CONCLUSION AND RECOMENDATION

5.1 Conclusion................................................................................ 135.2 Recomendation.......................................................................... 13

BAB VI IMPRESSION AND SUGGESTION

6.1 Impression................................................................................ 146.2 Suggestion................................................................................ 14

BAB VII REFERENCES.............................................................................. 15

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LIST OF TABLES

Table 3.1 Data flowtime of water.......................................................................................... 5

Table 3.2 Data of pincometer................................................................................................ 5

Table 3.3 Data flowtime of fluid through capillary.............................................................. 5

Table 4.1 All data measured and calculated......................................................................... 10

Table 5.1 Conclusion of kinematic viscosity....................................................................... 13

Table 5.1 Conclusion of dtnamic viscosity.......................................................................... 13

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LIST OF FIGURE

Figure 2.1 Relationship of viscosity Oil with Pressure ....................................................... 2

Figure 2.2 Relationship to Pressure Gas Viscosity .............................................................. 2

Figure 4.1 The Ostwald Viscometer which in problem........................................................ 8

Figure 4.2 The large bath of Ostwald viscometer........................................................................... 9

Figure 4.3 The relation between density and temperature................................................... 10

Figure 4.4 The relation between Kinematic viscosity and temperature............................... 11

Figure 4.5 The relation between Dynamic viscosity and temperature................................. 11

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VISCOSITY MEASUREMENT WITH OSTWALD VISCOMETER

I. PURPOSE OF EXPERIMENT

Knowing the usage of Ostwald Viscomemter for :

1. Determining the constant of Ostwald Viscometer2. Determining the viscosity fluid which flow in capillary pipe3. Determining the relation between viscosity and temperature.

II. BASIC THEORY AND PRINCIPLE OF EXPERIMENT

a. Basic Theory

Viscosity is an important parameter of the fluid flow, which is one

characteristic of the fluid. The viscosity of a fluid is a parameter to be

considered by a petroleum engineer, because it is intimately linked to the

process of fluid flow in porous media, the reservoir or fluid flow in the pipe

after the oil is produced. Viscosity is an important parameter to maximize the

production of a reservoir. High viscosity of the fluid causes the fluid to flow

difficult, therefore it is necessary that the method and special equipment

design.

Reservoir with a low viscosity, the high rate of production so as to save the

cost of equipment and production. In addition, the viscosity values can

provide information about the fluid content and the fraction of that of the

reservoir fluid. Reservoir fluid that has high viscosity, the fluid contains

heavy hydrocarbon fraction more than the fraction of light, otherwise the

fluid has a low viscosity, the hydrocarbon content of more than the light

fraction.

Viscosity is a measure of the reluctance of a fluid to flow .Base on kind there

are two types of viscosity, the kinematic viscosity is a measure of the

reluctance of the flow of a fluid to flow under the influence of gravity and

pressure loads are proportional to the fluid density, with units of cSt

(centistoke). And the dynamic viscosity is a measure of the viscosity of a

fluid move that is affected by a shear stress, with units cP (centipoise). One

In general, the size of the fluid viscosity decreases with decreasing in

temparature and pressure as the oil viscosity.

1

  

Figure 2.1 Relationship of viscosity Oil with Pressure

In figure 2.1 the oil viscosity decreases with decreasing pressure at a pressure

above Pb because the distance between the gas molecules dissolved in the oil

becomes more tenuous, making them easier to move while under pressure

Pb, decrease in pressure causes increased viscosity due to dissolved gas and

fluid escape loss of light oil components.

As for the influence of the gas temperature can lead to two different

conditions depend pressure zone.

 

Figure 2.2 Relationship to Pressure Gas Viscosity

In figure 2.2 for a low-pressure zone, temparature rise causes an increase in

gas viscosity.

This happens due to the low pressure zone molecules within a very tenuous

inter-molecular forces of attraction are more dominant than the style of

departure so that tends to unite and lead to an increase in the viscosity of the

gas.

For the high-pressure zone, the increase in viscosity causes a decrease in the

gas temparature. 2

This occurs because the high-pressure zone within the molecules close

enough repulsive force between molecules is more dominant than its style so

that the molecules tend to move freely and cause a decrease in the viscosity

of the gas.

In addition, there are several factors that can affect the viscosity of such size,

the presence of other substances that can increase the viscosity, molecular

shape where the viscosity increases with increasing double bond, the bonds

between the molecules in which the higher viscosity due to the strong bonds

between the molecules, eg in the presence of ties hydrogen, and the

magnitude of london style is influenced by the size and number of particles.

b. Pricnciple of Experiment

General equation of Poiseulle for capillary pipe

v= π d 2ht128 VI

− Et 2

v = Kinematic Viscosity (cSt)

d = Capillary pipe diameter (cm)

l = Capillary pipe length (cm)

h = Vertikal distance of miniskus (cm)

V = Liquid volume which flow in capillary (cm3)

E = Correction if kinetic energy (CSt/sec2)

t = Flow time (sec)

And the simpler equation is v = Cx t.

Correction of kinetic energy negligible with time if the flow time more than

200 sec with exception on general maeurement for viscosity measurement

3

Meanwhile for the Dynamic Viscosity can be found from the the relation

with kinematic viscosity

μ=ρ x v

ρ ¿ Density at the same temperature with the maesurement' s temperature

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III. DATA PROCESSING

Experimental Data1. Observation data

a. Determining the C constant of Viscometer

T(oC) Flowtime water (s)

35 248

40 207

Table 3.1 Data flowtime of water

b. Determining Fluid Density

Vpicnometer = 25 mL

Mpicnometer = 20.16 gram

T(oC) mpicnometer+oil moil

35 42.82 22.66

40 42.69 22.53

Table 3.2 Data of pincometer

c. Determining fluid viscosity

T(oC) Flowtime (s)

35 888

40 781

Table 3.3 Data flowtime of fluid through capillary

2. Data Calculation

a. Determining the C constant of viscometer

To determine the C constant we could use :

v=C xt

Where :

v=kinematic viscosity ( cSt )

C=Viscometer constant ( cm2

s2 )

t=flowtime(s)

We can use water as reference fluid to calculate the C constant. We already known the

kinematic viscosity of water at certain temperature. At 35 oC the kinematic viscosity of

water is 0.658 x 10-6 m2/s 5

For the obtained flowtime 207 s:

C= vt

C=(0,658 x10−2 cm2

s )207 s

C=3,178743961 x 10−5 cm2/s2

b. Determining the oil density

At 35oC

Moil = 22.66 gram

oil density=22.66 gram25 mL

=0,9064 gram/mL

At 40oC

Moil = 22.53 gram

oil density=22.53 gram25 mL

=0,9012 gram/mL

c. Determining the kinematic viscosity of oil sample

As we already known that the C = 3,178743961 x 10−5 cm2/s2 we can easily calculate

the kinematic viscosity of fluid. In this experiment we only tested one oil sample.

At 35 oC

t = 888 second

v=C xt

v=3,178743961 x1 0−5 cm2

s2 x888 s=0.02822724 St=2.822724 c St

At 40 oC

t = 781 second

v=C xt

v=3,178743961 x10−5 c m2

s2 x 781 s=0,024825990 St=2.4825990 cSt

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d. Determining the dynamic viscosity of oil.

We can see the relationship between kinematic viscosity dan dynamic viscosity as

μ= ρ x v

Where :

µ : dynamic viscosity (cP)

ρ : density (g/cm3)

v : kinematic viscosity (cSt)

for oil sample :

At 35 oC

Density = 0.9064 grammL

Kinematic viscosity = 2.822724 cSt

μ= ρ x v

μ=0.9064 g/cm3 x 2.822724 cSt

μ=2.5585170 cP

At 40 oC

Density = 0,9012 grammL

Kinematic viscosity = 2.4825990 cSt

μ= ρ x v

μ=0.9012 g /cm3 x2.4825990 cSt

μ=2.237318219cP

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IV. ANALYSIS

Assumption

The assumptions used in experimental is

1. There is no impurities in the tool.

2. Ostwald viscometer and Picnometer dry and clean.

3. No parallax error.

4. The oil temperature measured at the temperature of bath.

5. The temperature of oil in accordance with the desired temperature.

6. No change in the current system temperature viscosity measurements.

7. No change in temperature when the transfer of oil to picnometer.

8. Ostwald viscometer is seated at the right position.

9. The kinetic energy correction is neglected.

10. The water flow in Ostwald viscometer is laminar.

Practicum Sustainability

Practicum hampered because of the water that goes into the narrow slit of

Ostwald viscometer, causing the flow of oil to be hampered .It is resolved

by cleaning with diesel and then with soap.

So we did not obtain data flowtime of oil in capillary pipe.

Figure 4.1 The Ostwald Viscometer which in problem

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Tools

1. Ostwald Viscometer

Principle

Using flowtime as the function of viscosity fluid.

How it work

Mengalirkan fluida didalam ostwald dengan terlebih dahulu mengangkat fluida sampai batas atas kemudian mencatat beda waktu antar dua batas dan dapat diukut nilai viskositas fluida.

The advantage of Ostwald viscometer.

1. Viskometer Ostwald dapat digunakan untuk semua jenis cairan, baik cairan yang kental maupun cairan yang tidakkental.

2. Water bath yang besar memungkinkan untuk panas tetap terjaga dalam waktu yang cukup lama.

Figure 4.2 The large bath of Ostwald viscometer

3. Metode viskometer Ostwald lebih praktis dan efisien dalam penentuan nilai viskositas cairan dibandingkan dengan viscometer Redwood karena fluida yang mengalir dapat ditarik kembali dengan bola karet.

92. Picnometer

Principle

Measure the wight of fluid on certain volume.

How it work

Measure the weight of empty pincometer and the fluid using picnometer. And then calculate the density of fluid.

Result Analysis

From pengolahan data ,obtained :

T(O C) Oil density (g/mL) Kinematic viscosity

(cSt)

Dynamic Viscosity

(cP)

35 0.9064 2.822724 2.5585170

40 0.9012 2.482599 2.2373182

Table 4.1 All data measured and calculated

34 35 36 37 38 39 40 410.8980.899

0.90.9010.9020.9030.9040.9050.9060.907

Density vs Temperature

Density

Figure 4.3 The relation between density and temperature

Based on data experiment and the calculation didapatkan density at 35 o C

adalah 0.9064 dan at 40 o C adalah 0.9012. Dan dapat kesimpulan bahwa

density menurun dengan penambahan temperature yang disebabkan oleh

pemuaian fluida.

10

34 35 36 37 38 39 40 412.3

2.4

2.5

2.6

2.7

2.8

2.9

Kinematic Viscosity vs Temper-ature

Kinematic Viscosity

Figure 4.4 The relation between Kinematic viscosity and temperature

To calculate the kinematic viscosity in this module we need constant’s of

Ostwald viscometer. In the experiment of measuring the viscometer constant

we use water as reference liquid because we already know the water viscosity

in several temperature so once we obtain the flowtime of water in ostwald

viscometer we can easily calculate the viscometer constant C.

Based on the experiment we obtain that the kinematic viscosity if oil sample

at 35 o C is 2.822724 cSt and at 40 o C is 2,482599 cSt. This tendency of this

data is same to the theory that the higher the temperature lower the viscosity.

This happen because in larger temperature rhe molecule can move easily and

have larger kinetic energy than in lower temperature as mentioned in the

basic theory.

34 35 36 37 38 39 40 412

2.12.22.32.42.52.6

Dynamic Viscosity vs Temperature

Dynamic ViscosityDynamic Viscosity

Figure 4.5 The relation between Dynamic viscosity and temperature 11

The value of dynamic viscosity can obtained from the relation between

density of fluid and kinenatic viscosity as mentioned in principle of

experiment. The value that we obtained is 2.5585170 cP at 35 o C and

2.2373182 cP at 40 o C ,the tendency of data is the same with kinemaric

viscosity and has the same reason

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V. CONCLUSION AND RECOMENDATION

Conclusion :

1. The viscometer contant (C) is 3,178743961 x 10−5 cm2/s2

2. Viscosity and temperature is inversely proporsional.

3. The kinematic viscosity of oil sample is

Table 5.1 Conclusion of kinematic viscosity

4. The dynamic viscosity of oil sample is

Temperature

35 oC 40 oC

Oil sample 2.822724 cSt 2.482599 cSt

Table 5.1 Conclusion of dtnamic viscosity

Recomendation :

Assistant must check and ensure the competence of every student more detailed

again. We failed to obtain the data because we have one treat Ostwald by

washing them with soap.

And the laboratory must renew the equipment especially the wateh bath for

ostwald viscometer for better measurement of fluid viscosity calculation.

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VI. IMPRESSION AND SUGGESTION

Impression :

This is the easiest one practicum of all that I have taken and the assistants are

also very relaxed so I do not worry.

Suggestion:

Keep your goodness assistant!!

Temperature

35 oC 40 oC

Oil sample 2.5585170 cP 2.2373182 cP

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VII. REFERENCES

McCain, William D.Jr., The Properties of Petroleum Fluids, 2nd Edition, PennWell Publishing Co., 1990, Tulsa, Oklahoma.

W.R. Siagian, Utjok. Diktat Kuliah Fluida Reservoir. Departemen Teknik Pertambangan dan Perminyakan. 2002. Institut Teknologi Bandung, Bandung.

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