a study on the effectiveness of in-situ high...

iv

A STUDY ON THE EFFECTIVENESS OF IN-SITU HIGH INTENSITY

ULTRASONIC (HIU) IN INCREASING THE RATE OF FILTRATION

IN PALM OIL REFINING INDUSTRIES

AHMAD ZIAD BIN SULAIMAN

A thesis submitted in fulfilment of the

requirements for the award of the degree of

Master of Engineering (Chemical)

Faculty of Chemical and Natural Resources Engineering

Universiti Teknologi Malaysia

MARCH 2005

vi

“Dengan nama Allah yang Maha Pemurah lagi Maha Penyayang. Selawat dan Salam

ke atas junjungan besar Nabi Muhammad S.A.W.”

“Specially dedicated to my wife and mum, sister, brothers and all of my friends.”

vii

ACKNOWLEDGMENT

I would like to express my sincere appreciation and thanks to my main thesis

supervisor Associate Professor Dr. Rosli Mohd Yunus and co-supervisor,

Associate Professor Dr. Radzuan Junin for their guidance, precious advices,

critics, friendship and continuous support throughout this study.

I am grateful to all staff and researchers at Faculty of Chemical & Natural

Resources Engineering, Research Management Center (RMC), Felda Oil Product

(FOP) Pasir Gudang, Mr Ng Beng Hooi from Crest Ultrasonic for supplying the

ultrasonic systems and providing the technical advices, Professor Dr Hathaichanok

Duriyabunleng from University of Chulalangkorn Bangkok , Mr Choo Chee Wei

from PINTAS IP, Puan Sharifah Bt Hashim and my friends who cheered up my life.

I am owing a special debt of gratitude for the financial support by Ministry of

Science, Technology and Innovation Malaysia (MOSTI) under the scholarship of

National Science Fellowship Scheme (NSF) and IRPA grant project.

Lastly, I wish to express my unlimited appreciation to my beloved wife and

my family for their irreplaceable encouragement, undying love and prayers. To my

mum for her infinite patience, sacrifice and understanding during the years of this

study.

Above all, I thank God the almighty for his grace, mercy and guidance which

enable the successful completion of this study.

viii

ABSTRACT

Application of ultrasound wave fields in the filtration and separation

technology is a new and clean technology and offers an attractive alternative to the

classical cleaning processes. Fouling phenomenon is a major bottleneck in this

separation technology, as expected in the industrial application of such finely porous

media. As the filtration process continues, the concentration of solute keeps building

up on the filter surface to form a filter cake. This results in a continuous decline of

the flux. In this study, the effect of intermittent application of ultrasound wave fields

on the filtration of bentonite in Refined Bleached Deodorized (RBD) oil suspension

is presented. In general, the intermittent application of ultrasound fields increased the

overall flux of the filtration. The main mechanism responsible in reducing the

thickness of the filter cake, and hence increasing the rate of filtration, is the

cavitation phenomenon. Four parameters affecting the ultrasound assisted filtration

were investigated. The parameters include the filtration cycle time, sonication cycle

time, applied pressure, and ultrasound intensity. The highest percentage of

improvement achieved in the study was 88.47%, conducted at 5 minutes filtration

cycle time and 12 minutes sonication cycle time. The result also showed that the

degree of flux improvement was initially increased with the increase in the applied

pressure. However, as the pressure was further increased, compaction of cake layer

took place which constricted the filtrate path, and hence, reduced the degree of flux

improvement. On the other hand, the degree of flux improvement was linearly

related to the ultrasound intensity. In this study, the highest flux was obtained when

the ultrasound intensity was set at 1.2109 W/cm2. An Ultrasonic Clean-in-Place

(UCIP) method of cleaning the filtration system was also developed in this study.

The UCIP method showed an effective method of cleaning, with 71.5% flux

recovery achieved after only 15 minutes of UCIP cleaning processes. Empirical

models were developed in this study to represent the profile of the filtration process.

The developed model showed good fits with the experimental data, with error not

more than 5%.

ix

ABSTRAK

Penggunaan medan gelombang ultrabunyi di dalam teknologi penurasan dan

pemisahan adalah baru dan teknologi pembersihan menawarkan alternatif kepada

pembersihan secara klasik. Fenomena Penyumbatan adalah gangguan terbesar di

dalam teknologi pemisahan ini. Semasa proses penapisan berterusan, kepekatan

daripada suspensi akan membentuk lapisan kek di atas permukaan penapis dan ini

menyebabkan penurunan kepada fluks secara berterusan. Di dalam kajian ini, kesan

sela pengaplikasian gelombang ultrabunyi ke atas penapisan lumpur teraktif di dalam

penapisan, pelunturan dan penyahbauan (RBD) suspensi minyak adalah diterangkan.

Secara umum, pengaplikasian gelombang daya ultrabunyi bersela meningkatkan

keseluruhan fluks di dalam penapisan. Mekanisma utama yang bertanggungjawab di

dalam mengurangkan ketebalan kek dan seterusnya meningkatkan kadar penapisan

adalah fenomena peronggaan. Empat parameter yang memberi kesan kepada

penapisan berbantukan ultrabunyi telah dikaji. Parameter itu termasuk kitaran masa

penapisan, kitaran masa sonikasi, kesan tekanan dan keamatan ultrabunyi. Peratus

tertinggi peningkatan kadar penurasan yang dicapai di dalam kajian ini adalah

88.47% yang dijalankan pada 5 minit kitaran masa penapisan dan 12 minit kitaran

masa sonikasi. Keputusan juga menunjukkan bahawa darjah pembaikan fluks telah

pada awalnya meningkat dengan peningkatan di dalam kesan tekanan. Oleh sebab

itu, apabila tekanan ditingkatkan kek akan menjadi padat. Seterusnya, darjah

pembaikan fluks akan berkurang. Sebaliknya, darjah pembaikan fluks dihubungkan

secara linear terhadap keamatan ultrabunyi. Di dalam kajian ini, fluks tertinggi yang

dicapai apabila keamatan ultrabunyi telah disetkan pada 1.2109 W/cm2. Kaedah

sistem penapisan Pembersihan Setempat Ultrabunyi (UCIP) juga telah dibangunkan

di dalam kajian ini. Kaedah UCIP menunjukkan keberkesan kaedah pembersihan

dengan 71.5% mendapat kembali fluks yang dicapai selepas hanya 15 minit proses

pembersihan UCIP. Model empirik telah dibangunkan di dalam kajian ini untuk

mewakili profil proses penapisan. Model yang dibangunkan menunjukkan

kesesuaian yang baik dengan data eksperimen dengan ralat tidak melebihi 5%.

x

TABLE OF CONTENTS

CHAPTER TITLE PAGE

1 INTRODUCTION 1

1.1 Objective of Study 5

1.2 Scopes of Study 5

1.3 Contribution of Study 6

2 LITERATURE REVIEW

2.1 Basic Theory of Filtration 7

2.1.1 Cake Accumulated on the Filter Surface 9

2.1.2 Constant-Pressure Filtration 12

2.2 History of Palm Oil 14

2.3 Overview of the Malaysian Palm Oil Industry 15

2.4 Palm Oil Refinery Processing 16

2.4.1 Palm Oil Degumming 17

2.4.2 Palm Oil Bleaching (Adsorption Clay) 17

2.4.3 Filtration 21

2.5 Pressure Leaf Filter 21

2.5.1 Working Principle of Pressure Leaf Filter 22

2.5.2 Designation of Pressure Leaf Filter 22

2.5.3 Application and Importance 25

2.6 Filter Characterization 26

2.7 Causes of Flux Decline 28

2.7.1 Definition of Flux 29

2.8 Methods of Solving Flux Decline Phenomena 30

xi

2.8.1 Sample Pretreatment 30

2.8.2 Cake Treatment 30

2.8.3 Filtration Aid 31

2.8.4 Ultrasonic Field Assisted 31

2.9 Conventional Cleaning Method for Leaf Filter

in RBD Palm Oil 33

2.10 Clean-In-Place (CIP) 34

2.10.1 Historical Background 35

2.10.2 Types of CIP System 36

2.11 Theory of Sound Waves 36

2.12 Classification of Sound Waves 39

2.13 Parameters of Sound 41

2.14 Ultrasound 41

2.15 Piezoelectric Transducer (PZT) 42

2.15.1 Physical Effects of Power Ultrasound 43

2.15.2 Cavitation 43

RESEARCH METHODOLOGY

3 METHODOLOGY 45

3.1 Introduction 45

3.2 The Sound Generating Equipment 46

3.2.1 The Power Generator 48

3.2.2 The Genesis Piezoelectric (PZT)

Transducers 49

3.3 Feed Sample Preparation 49

3.4 Experimental set-up and Equipment 50

3.5 The Filters and Ultrasonic Filtration Vessel 52

3.6 Design of Research Work 54

3.6.1 Experimental procedure for

Baseline determination 54

3.6.2 Experimental method to determine

xii

the effectiveness of in-situ ultrasonic

assisted system in increasing the rate

of filtration. 57

3.6.3 Experimental Procedure to determine

the effectiveness of Ultrasonic Clean In

Place (CIP) in comparison to conventional

cleaning method. 58

3.6.3.1 Filtration Experiment Using

Clean Oil 60

3.6.3.2 Cleaning Experiment by UCIP 60

3.6.4 Development of an empirical model of

in-situ ultrasonic assisted filtration system 61

4 MODELLING & SIMULATION 62

4.1 Introduction 62

4.2 Analysis on Total Volume of Filtration 63

4.2.1 Step of Analysis in Microsoft Excel 2000 63

4.3 Analysis on the Difference Between Initial and

Final Filtrate Flow Rate 65

4.3.1 Step of Analysis in Microsoft Excel 2000 65

4.4 Analysis on Comparative Error Between the Data 66

4.4.1 Step of Analysis in Microsoft Excell 2000 67

5 RESULTS & DISCUSSION 68

5.1 Experimental Data for Baseline Determination 69

5.2 The Effectiveness of In-Situ Ultrasonication in

increasing the Rate of Filtration 70

5.2.1 Effect of Sonication Cycle Time 70

5.2.2 Effect of Filtration Cycle Time 82

5.2.3 Effect of Applied Pressure 88

5.2.4 Effect of Ultrasound Intensity 92

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5.2.5 Effect of Ultrasonic Application on the

Spesific Cake Resistance ( 95

5.3 Ultrasonic-Clean-In-Place (UCIP) of Stainless

Steel Pressure Leaf Filter Fouled by palm Oil

Suspension 98

5.4 Modelling of Filtration Process 100

5.4.1 Analysis on the Error between the

Tabulation of Data between Empirical

Model and Experimental Result 101

5.4.2 Analysis on the Effect of Sonication in

Terms of Varying Pressure 102

5.4.3 Results on Data Retrofitting Approach 103

6 CONCLUSION AND RECOMMENDATIONS 108

REFERENCES 111

PUBLICATIONS 116

PATENT 117

PROJECT FUNDING 118

APPENDICES 119

xiv

LIST OF TABLES

TABLE TITLE PAGE

2.1 Typical properties of adsorption clays 18

2.2 Categories of filter characterization 27

3.1 A summary of the operating conditions of the experiments 54

3.2 Combinations of sonicated and un-sonicated filtration

intervals

57

5.1 Percentage of flux increment as a function of sonication cycle

time at 5 minutes filtration cycle time. 75

5.2 Percentage of flux increment as a function of sonication

cycle time at 8 minutes filtration cycle time. 77

5.3 Percentage of flux increment as a function of sonication cycle

time at 10 minutes filtration cycle time. 78

5.4 Percentage of flux increment as a function of sonication

cycle time at 12 minutes filtration cycle time. 79

5.5 Least square regression data points of all the sets of filtration

cycle time 81

5.6 The percent increment (%) of Sonication at 40 kHz in filtration

of activated clay in oil suspension (Comparison between

5 minutes F , 8 minutes F , 10 minutes F and 12 minutes F in

4 minutes sonication cycle) 83



xv







5.9 Least square regression data points of all the sets of

sonication cycle time 87

5.10 The summary of percentage of flux improvement for all the

investigated applied pressures 92

5.11 The summary of percentage of flux improvement for all the

investigated ultrasound intensities 94

5.12 Value for for each condition 97

5.13 The summary of the cleaning performance 100

5.14 Results on the Analysis on the percentage of error between

the tabulation of data between empirical model and

experimental results. 102

5.15 Results on the analysis on the effect of sonication in terms of

varying pressure. 103

xvi

LIST OF FIGURES

FIGURE TITLE PAGE

2.1 Schematic Diagram of Porous Media 8

2.2 Proportional relation between pressure drop and flow rates

of clean liquid flowing through fixed porous media

9

2.3 Section through a filter cake 10

2.4 Determination of constants in a constant-pressure filtration

run

14

2.5 The Typical Flow Chart for the Palm Oil Process 20

2.6 Typical pressure leaf filter used in the vegetable oil

industry

22

2.7 Filtration elements used in an automatic Niagara Leaf

Filter

23

2.8 The design of stainless steel filtration mesh 24

2.9 Rings for Metafilter 24

2.10 Vertical arrangement of pressure leaf filter 25

2.11 Horizontal arrangement of pressure leaf filter 26

2.12 A Schematic presentation of the three stages in flux

decline: (1) Initial rapid drop from the flux of pure water

filtration: (II) long-term gradual flux decline: and (III)

time independent steady-state flux 28

2.13 Steps of conventional cleaning for leaf filter in Palm Oil

Process (Cleaning By Rinsing and Recirculation) 34

2.14 The coils of a spring to represent individual molecules of a

sound conducting medium 37

2.15 Wave and particle movement 38

xvii

2.16 An acoustic spectrum illustrating the range of frequencies

of mechanical waves and some of their common sources

of generation of application 40

2.17 Mechanism of bubble growth followed by its collapse

during cavitation induced by ultrasound 44

3.1 Schematic diagram of the ultrasonic generating system 47

3.2 Genesis ultrasonic generator (front & rear) with adjustable

output power intensity control. 48

3.3 The flow process for the preparation of the feed sample

Schematic 50

3.4 Diagram and of the experimental setup for Niagara Leaf

Filter.

51

3.5 The Lab Scale Design of Niagara Leaf Filter 52

3.6 Cross-sectional of Ultrasonic Filtration Vessel view (top

view, front view, side view) and method of bonding the

transducers on to the system.

53

3.7 Flow Chart of the Filtration Experimental 55

3.8 The flow chart of the filter leaf cleaning method 56

3.9 Flow process of Conventional and In-situ Cleaning

Method

59

4.1 Flowchart of the modeling methodology on the total

volume of filtrate. 64

4.2 Flowchart of the modeling methodology of analysis on the

difference of initial and final filtrate flow rate 65

4.3 Flowchart of the modeling methodology of analysis on

comparative error between the data 67

5.1 Typical curve of filtrate flux versus filtration time in the

filtration of Activated Clay from RBD Oil. 69

5.2 Intermittent application of ultrasound field in filtration

process 71

5.3 a) Scanning electron micrograph (x400) of cake structure

after 10 minutes filtration (before ultrasonication) 72

5.3 b) Scanning electron micrograph (x400) of cake structure

xviii

after Ultrasonication 72

5.4 Effect of varying the sonication cycle time. 73

5.5 The effect of varying the sonication cycle time on the

filtration of activated clay in oil suspension (at filtration

cycle time of 5 min). 75



cycle time of 8 min) 77







5.9 Summary of equilibrium flux increment as a function of

Sonication Cycle Time for various Filtration Cycle Time. 81

5.10 Sonication at 40 kHz in filtration of activated clay in oil

suspension (Comparison between 5 minutes F , 8 minutes

F , 10 minutes F and 12 minutes F in 4 minutes sonication

cycle)

83



F , 10 minutes F and 12 minutes F in 8 minutes sonication

cycle)

84



F , 10 minutes F and 12 minutes F in 12 minutes

sonication cycle)

85

5.13 Summary of equilibrium flux increment as a function of

Filtration Cycle Time for various Sonication Cycle Time. 87

5.14 Graph of Flux vs Filtration Time For the Pressure Range

between 3 – 6 bars (without sonication) 89

5.15 Graph of Flux vs. Filtration Time with Pressure at 3 bars 89

xix




5.19 Graph of Flux vs Filtration Time For the Intensity Range

between 0.2422 W/cm2 - 1.2109 W/cm2 93

5.20 The percentage of flux improvement as function of

ultrasoundintensity 94

5.21 Graphical determination of constants in a constant-

pressure filtration run without the application of ultrasonic

wave

95


pressure filtration run with the application of ultrasonic

wave at optimum condition (5f:12s) 96


pressure filtration run with the application of ultrasonic

wave at lowest condition (12f:4s) 96

5.24 Influence of sonication exposure time on flux recovery in

the cleaning-in-place of fouled filter (10 minutes

sonication exposure time) 99

5.25 Influence of sonication exposure time on flux recovery in

the

cleaning-in-place of fouled filter (15 minutes sonication

exposure time)

99

5.26 The combination of the influence of sonication exposure

time on flux recovery in the cleaning-in-place of fouled

filter (x) clean filter level; ( ) 15 minutes sonication; ( )

10 minutes sonication; (X) cleaning without ultrasound 100

5.27 Sample graphical result of comparison between empirical

model an experiment results. 104

5.28 Sample graphical result of comparison between the effect

of sonication. 104

5.29 Kp vs influencing factor of pressure(bar) 105

xx

5.30 Ki vs influencing factor of intensity of ultrasonic

wave(W/cm2) 106

5.31 Ks vs influencing factor of sonication time(minute) 106

xxi

LIST OF SYMBOLS

˚C - Degree Celsius

P - Pressure Drop

A - Cross-sectional area

CPO - Crude Palm Oil

F - Frequency

G - gram

HIU - High Intensity Ultrasonic

I - Intensity (W/m2)

In - inches

Kg - Kilogram

KHz - Kilohertz

L - Bed Depth

MPOB - Malaysian Palm Oil Board

Pa - Pressure in Pascal

PZT - Piezoelectric Ceramic Transducer

RBD - Refined, Bleached and Deodorized

S - time in second

So - Specific surface area

UCIP - Ultrasonic Clean In Place

Uo - Superficial velocity

V - Filtrate volume

W - Watt

- Specific cake resistance (m/kg)

- Porosity

µ - Liquid viscosity

µm - Micrometer

- Density (kg/m3)

xxii

LIST OF APPENDICES

APPENDIX TITLE PAGE

A Technical Specifications 119

B Experimental Data (Sonication & Filtration Cycle) 125

C Experimental Data (Pressure & Power Intensity) 152

D Saw Teeth Graph Of Sonication & Filtration Cycle Time 166

E Data of Empirical Model 173

1

CHAPTER 1

INTRODUCTION

Palm oil industry has been the bread and butter of Malaysian industry ever since

palm tree was brought into the country in the 1960’s. The fast growth of this industry

has made Malaysia to be the largest producer of palm oil for many years. Palm tree is

easily grown in tropical climate countries. Hence, the profitable industry has been

adopted by neighboring countries such as Thailand, Indonesia, Vietnam, Cambodia, as

well as Philippines. Realizing the competitiveness of the industry and the advantages of

neighboring countries with large cultivating land, much research has been focused on

improving the overall operation of the industry so as to increase its productivity.

In any chemical and oleochemical industry, separation processes are of key

importance, whether it is a minor or the main part of operation. Choosing the best

separation method for the job is crucial to ensure economic operation. Filtration, for

instance, is a typical solid-liquid separation technique commonly used in the industry. It

is preferred from other solid-liquid separation techniques because it offers low

investment costs, easy to scale up, long lifespan of the filters because of mild operation

conditions, compact construction and fast, easy to make installation, low energy, and

low chemical consumption.

2

In the edible/vegetable oil industry, filtration is an important unit operation for

the separation of bleaching earth from the treated oil. In this process, pressure leaf filters

are most commonly used for this purpose.

During operation, the rate of filtration decreases progressively as a result of

filter cake build-up on the surface of the filter medium. The process comes to an end

when the whole chamber is filled with solids, normally about 2 ½ hours (for standard

size filter) after separating 500 kg of solids from the treated oil. The separating system

requires a regeneration process, which normally takes about 1½ hours. The sequence of

filtration and regeneration process is repeated for approximately two to three weeks,

depending on the condition of the filter medium, before a thorough cleaning method is

conducted. The conventional cleaning of the filter leafs include disassembling of the

filter unit, immersing the filter leafs in caustic solution, followed by high pressure water

cleaning (60- 90 bar) and steam cleaning. The total downtime from disassembling,

cleaning, up till assembling of the filter system averages about 2 days. The implication

of long downtime period in the plant operation is its higher operation and capital cost in

which the plant has to invest on the standby filter unit and on the cleaning operation.

Presently, there has not been much work focusing on developing methods to

improve the filtration process. Improvement in the rate of filtration, for instance, will

reduce the operation time, and hence, increase the productivity. The present method of

knocking or vibrating the filter leaf is only applicable after the filtration process is

completed, i.e. during the regeneration of the filter medium. Vibrating or knocking the

filter leaf during the filtration is not adopted because it may disrupt the whole formation

of the filter cake. This is not acceptable since in filtration processes, filter cake is the

true medium performing the solid-liquid separation.

Upon close examination of the filtration process, the main problem which

dominates in reducing the flux during the filtration process is the fouling phenomenon.

Fouling refers to a combination of flux reducing factors which include the blinding of

3

filter medium as a result of particles retained on the filter surface as liquid passes

through the filter medium, cake formation, and the formation of concentrated layer near

the filter surface. Many methods have been proposed to reduce fouling. In general, the

methods include sample pretreatment, filter pretreatment, abrasives, filtration aids, back

flushing, baffling and oscillatory flow techniques, electric field assisted and ultrasonic

field assisted.

The common method used to secure high filtration rate is by pretreating the feed

solution before entering the filtration system. The method employs flocculating agent,

causing particles to agglomerate into larger entities, thereby preventing them from

penetrating inside the pores. Hence, a greater filtrate flux can be achieved during

filtration. Another method of reducing the fouling phenomenon is by modification of the

filter surface properties. Surface characteristics and filter morphology have a

considerable effect on the adsorption of solution and, as a result on the separation. The

addition of filtration aid to the feed stream prior to filtration of a suspension increases

the filtration rate by modifying the porosity of the filter cake and the particle size

distribution which increases its permeability. A common type of filtration aid is

diatomaceous earth but the fact that the filtration aid should be retrieved in the blow-

down of the stream to be recycled makes this technique rather difficult to apply. This

technique is more suitable for dead-end filtration operation, particularly the conventional

filtration such as plate and frame filter press, leaf filter, vacuum belt filter etc.

There are reports of the use of abrasive materials, added to the mixture in order

to disrupt the layer on the surface of the filter. Another method of reducing the fouling

phenomenon is baffling and oscillatory flow techniques. These techniques are to

promote and/or increase turbulent condition near the filter surface. These techniques also

have been used by several workers in order to improve the filtration flux. The presence

of the baffle resulted in a radial flow inside the filter, and hence, the path length was

increased. However, these methods are more suitable in membrane filtration rather than

in the conventional filtration since they require crossflow mode of filtration to cause the

sweeping action on the filtering surface. Back-flushing technique is an effective method

4

to remove fouling layer from the filtering surface. In this method, the filtrate is

negatively pressured to force the liquid to flow back into the system through the filter

medium. The back flushing will cause the cake to break/disrupt and forces the particles

to reenter the bulk suspension. However, the total disruption of the cake during the

filtration operation is not wanted in the conventional filtration since in this kind of

filtration, the cake layer is the true medium which performs the separation.

The application of ultrasound wave fields in filtration operation, particularly

membrane filtration, has been identified as a new and clean technology and as an

alternative to the classical cleaning. The use of ultrasound fields in the control of filter

fouling and filter cake formation, especially in the membrane filtration, has been studied

and proven by a number of researchers. The application of ultrasound wave field in

membrane filtration processes was found to improve the rate of filtration and reduce the

rate of filter fouling. Nevertheless, the technique has not been applied in the

conventional filtration operation, especially in leaf filtration processes, to increase

productivity.

The suitability of each method used in solving the flux decline phenomenon

depends on the qualities of the foulants as well as the nature of the filter. The economic

and production demands must also be considered in choosing the appropriate method of

solution. Another important consideration is the fact that in pressure leaf filter operation

a minimal layer of filter cake is required to achieve good separation of solid-liquid

suspension. Thus, the acquired technique must be able to reduce the fouling

phenomenon without losing the efficacy of the filtration.

Realizing the capability of ultrasound wave fields in cleaning processes, the

technique was studied in this research to increase the rate of filtration of leaf filter. The

application of high intensity ultrasound in the solid-liquid suspension would cause the

occurrence of cavitation microbubbles in the liquid medium which is responsible in

5

removing particles especially at the interface between the liquid and solids in the

suspension.

1.1 Objectives of Study

The objective of the research is to investigate:

i) The possibility of intensifying the filtration operation,

ii) Increasing the rate of filtration,

iii) Reducing the downtime, by means of Ultrasound Wave Fields.

1.2 Scopes of Study

To achieve the objectives, four scopes have been identified in this research. The scopes

of this research are listed as below:

1.2.1 To study the effectiveness of In-Situ ultrasonic cleaning system in increasing the

rate of filtration of bleaching earth suspension. Several experimental works were

carried out to examine the behavior of the filtration in the presence of ultrasound

field.

1.2.2 To identify the optimum combination of filtration cycle time and sonication

cycle time which give the highest flux increment. The rate of filtration was

influenced by the filtration time and by the duration of ultrasound exposure.

Thus, research was carried out to determine the optimum condition of the two

parameters.

6

1.2.3 To study the effect of ultrasound intensity on the degree of flux increment.

The degree of flux increment was also influenced by the intensity of the

ultrasound field. This study established the optimum ultrasound intensity to be

used for the system which results in the best flux improvement.

1.2.4 To study the effectiveness of ultrasonic Clean-In-Place (CIP) method in

comparison to Conventional method. A Clean-In-Place method was developed in

the research study to clean the filter leaf and the filtering chamber without

having to disassemble the filtration system. This scope of study compares the

effectiveness of the developed method, with the conventional method of

cleaning.

1.2.5 Development of an empirical model. From the results gathered in this study,

analysis of transport processes taking place in the separation of spent bleaching

earth from oil suspension was undertaken. An empirical model was developed

which enable the prediction of filtration rate as a function of various parameters.

1.3 Contribution of the study

A positive outcome from the research would bring a new dimension to related

industries in improving the rate of production due to an effective and efficient high

intensity ultrasonic cleaning and process design for the purpose of In-situ cleaning

method, a demonstration process plant, application of advance technology in high

intensity ultrasonic cleaning and at the same time offering potential savings in the

operational costs.

112

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117

PUBLICATIONS

Sulaiman A.Z., Yunus, R.M. Intensified Niagara Leaf Filtration Via In-Situ Ultrasonic

wave Fields. Symposium of Malaysian Chemical Engineers (SomChe) 2001 ,

September 2001, Johor Bahru, Malaysia.

Sulaiman A.Z,Yunus, R.M.Radzuan Junin. Development of High Intensity Ultrasonic

(HIU) for Stainless Steel Filter Leaf Cleaning. Regional Symposium on Chemical

Engineering (RSCE) 2001 , October 2001, Institute Technology Bandung, Indonesia

Sulaiman A.Z,Yunus, R.M., H. Abdullah “ Modelling of Ultrasonic in Increasing The

Rate of Filtration in Palm Oil Industry. World Engineering Congress (WEC) 2002,

July 2002, Kuching Sarawak

Sulaiman A.Z,Yunus R.M, Effect of Sonication For In-Situ Stainless Steel Leaf

Filtration. Asian Pacific of Chemical Engineering Conference (APPCHE 2004) 17 to

21 October 2004 at Kitakyushu, JAPAN

Sulaiman A.Z,Yunus R.M, A Study on the Effectiveness of In-Situ High Intensity

Ultrasonic (HIU) in Increasing the Rate of Filtration in Palm Oil Refining Industries.

4th Seminar National Science Fellowship (NSF), Ministry of Science, Technology &

Innovation Malaysia, 20 to 21 Disember 2004 at Vistana Hotel, Penang (Silver

Medal Award Presenter)

118

PATENT

Sulaiman A.Z, Rosli M.Y. In-Situ High Intensity Ultrasonic (HIU) Asissted for

Stainless Steel Leaf Filtration. Malaysian Patent Identification Number :

PI 20032885

a study on the effectiveness of in-situ high...

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