i

The Islamic University Gaza

Higher Education Deanship

Faculty of Engineering

Civil Engineering Department

Engineering projects management

:

Applying Value Engineering Concept in Project Life Cycle

Case Study: Deir El Balah Desalination Plant

Submitted by:

Eng.Samer El Namara

Supervised by:

Dr. Nabil Sawalhi

A Thesis Submitted in Partial Fulfillment of Requirements for the Degree of Master of

Science in Engineering Projects Management

3414 -3131

iii

Acknowledgement

I would like to express my sincere gratitude to people who assisted me in the realization of

this research:

Dr. Nabil Sawlhi, Islamic University of Gaza, who is my supervisor for his efforts and

cooperation .

Eng.Rebhy El Sheikh, Deputy Chairman of Palestinian water authority, for his great

support and generous assistance and encouragement

Eng.Omar Shataat, Costal municipalities water utility, for his collaboration and assistance

in providing me with the relevant material.

To the Coastal Municipalities Water Utility staff, for their valuable contribution in the

questionnaire.

The value engineering team, for their support and technical assistant

The professionals I interviewed and those who either responded to the questionnaire or

apologized for other engagements, and finally

I would like also to express my sincere gratitude to the Islamic University of Gaza for its

effort in the facilitation of the graduate studies.

ii

)) ((

88

iv

Presentation

To my dear mother and to my faithful wife for their honest supplications to Allah to facilitate my mission in performing the enclosed thesis.

Also, to my kids whom motivated me to apply for this master wishing them good health and promising future inshAllah.

Samer El Namara

v

Abstract

One of the most important challenges that face the people in Gaza Strip is the scarcity of

natural water resources along with continuous growth of consumption level. This situation

lead to a huge deficit in aquifer balance and force the authorities to look for an optimal

alternative source to overcome this difficulty through seawater desalination.

However, the cost of construction of desalination plants have been rapidly increasing in the

last few years, this issue may refer to different reasons related to the project components

and /or other factors affecting the establishment of the plant.

Accordingly, it was very important to find an effective technique to explore this

phenomena and reduce its effect on the cost of water production offered to beneficiaries.

This was clearly presented through the application of value engineering concept.

In order to practically examine the impact of applying this concept through desalination

plants, an intensive survey was conducted to elaborate the most important factors affecting

the establishment of the desalination plant.

Moreover, several interviews were conducted with experts in the field to cross check the

validity of the survey results and figure out other possible considerations

The findings from this investigation was considered in applying the value engineering

concept on a selected case study located in Gaza Strip : Deir El Balah desalination plant in

order to examine the impact of application value Engineering on this project .

Through the value engineering application process, several proposals were discussed and

considered in the study, it was found that the application of the value engineering concept

on the selected case study lead to direct impact in cost saving of approximately 10.33 % for

this project in addition to saving of annual operational cost approximately 330,000USD.

On the light of this result , it was confirmed that applying value engineering is very helpful

tool for such project which will lead to significant saving in cost.

Due to the limited experience in this field in Gaza Strip, its strongly recommended to have

further studies in Gaza strip in this domain to reach to the optimum alternatives in

implementing the value engineering in similar projects

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vii

LIST OF CONTENTS

CHAPTER (1) INTRODUCTION

1.1. BACKGROUND .................................................................................................................................. 2

1.2. RESEARCH PROBLEM .................................................................................................................... 2

1.3. RESEARCH AIM ................................................................................................................................ 3

1.4. RESEARCH OBJECTIVES ............................................................................................................... 3

1.5. JUSTIFICATION ................................................................................................................................ 4

1.6. PRACTICAL SIGNIFICANCE OF THE RESEARCH .................................................................. 4

1.7. HYPOTHESIS ..................................................................................................................................... 5

1.8. CONCEPTUAL FRAME WORK ...................................................................................................... 5

CHAPTER (2) LITERATURE REVIEW

A. PART ONE: VALUE ENGINEERING ..................................................................................................... 7

2.1 INTRODUCTION ............................................................................................................................... 7

2.2 HISTORY OF VALUE ENGINEERING .......................................................................................... 7

2.3 DEFINITION OF VALUE ENGINEERING .................................................................................... 9

2.4 VALUE METHODOLOGY APPLICABILITY ............................................................................. 10

2.5 WHEN VALUE ENGINEERING IS USED .................................................................................... 11

2.6 PROCESS OF VALUE ENGINEERING APPLICATION ........................................................... 12

2.6.1 SAVE INTERNATIONAL APPROACH (1999) ................................................................................... 12 2.6.1.1 PRE-STUDY ................................................................................................................................. 13

2.6.1.2 The Value Study ..................................................................................................................... 15 2.6.1.3 Post Study ............................................................................................................................... 20

2.6.2 VALUE MANAGEMENT ................................................................................................................... 20 2.6.3 ACQUISITION LOGISTICS ENGINEERING. ...................................................................................... 21 2.6.4 CALDWELL ...................................................................................................................................... 22 2.6.5 DELL'ISOLA .................................................................................................................................... 24

B. PART TWO: WATER DESALINATION ............................................................................................... 25

2.7 HISTORY OF DESALINATION ..................................................................................................... 25

2.8 DESALINATION TECHNOLOGIES ............................................................................................. 27

2.8.1 THERMAL TECHNOLOGIES ............................................................................................................ 28 2.8.2 MULTI-STAGE FLASH DISTILLATION (MSF) ................................................................................ 28 2.8.3 MULTI-EFFECT DISTILLATION (MED) ......................................................................................... 29 2.8.4 VAPOR COMPRESSION DISTILLATION ........................................................................................... 30 2.8.5 MEMBRANE TECHNOLOGIES ......................................................................................................... 30

2.8.5.1 Electrodialysis (ED) and Electrodialysis Reversal (EDR) .................................................... 30 2.8.5.2 Reverse Osmosis (RO) and Nanofiltration (NF) .................................................................. 31

2.9 FACTORS AFFECTING COST OF DESALINATION ................................................................ 33

2.9.1 SELECTION OF INTAKE AND CONCENTRATE DISCHARGE............................................................. 33

viii

2.9.2 FEED AND FINISHED WATER QUALITY .......................................................................................... 35 2.9.3 DISTRIBUTION ................................................................................................................................. 36 2.9.4 PERMITTING AND REGULATORY ISSUES........................................................................................ 37 2.9.5 PROJECT DELIVERY MECHANISM ................................................................................................. 37 2.9.6 OTHER ASSOCIATED COSTS ........................................................................................................... 38 2.9.7 OPERATION AND MAINTENANCE COST ......................................................................................... 38 2.9.8 QUALITY OF FEEDING WATER ........................................................................................................ 39 2.9.9 PRETREATMENT ............................................................................................................................. 39 2.9.10 OTHER ELEMENTS AFFECTING THE COST ANALYSIS ................................................................. 39

CHAPTER (3)RESEARCH METHODOLOGY

3.1 INTRODUCTION ............................................................................................................................. 42

3.2 QUANTITATIVE APPROACH ...................................................................................................... 42

3.3 DATA ANALYSIS ............................................................................................................................. 42

3.4 THE POPULATION OF STUDY .................................................................................................... 43

3.5 THE SAMPLE OF THE STUDY ..................................................................................................... 43

3.6 SETTING OF THE STUDY ............................................................................................................. 43

3.7 ELIGIBILITY OF THE STUDY ..................................................................................................... 44

3.7.1 INCLUSION CRITERIA ..................................................................................................................... 44

3.8 QUESTIONNAIRE MAIN CATEGORIES .................................................................................... 44

3.8.1 PART ONE (DEMOGRAPHIC INFORMATION) .................................................................................. 44 3.8.2 PART TWO (THE MOST IMPORTANT FACTORS AFFECTING THE ESTABLISHMENT OF DESALINATION PLANTS).............................................................................................................................. 45 3.8.3 PART THREE (THE PARTIES INVOLVED) ....................................................................................... 45

3.9 STUDY INSTRUMENT (DATA COLLECTION TOOL) ............................................................ 45

3.10 STATISTICAL ASSUMPTIONS AND CRITERIA ...................................................................... 46

3.10.1 QUESTIONNAIRE SCALING ......................................................................................................... 46 3.10.2 RELIABILITY AND VALIDITY OF THE MEASURE ....................................................................... 46 3.10.2.1 VALIDITY OF THE MEASURE ..................................................................................................... 46 3.10.2.2 CONTENT VALIDITY ................................................................................................................... 46 3.10.2.3 STATISTICAL VALIDITY OF THE MEASURE ............................................................................... 47 3.10.2.4 INTERNAL CONSISTENCY ........................................................................................................... 47 3.10.3 RELIABILITY OF THE SCALE ...................................................................................................... 50 3.10.3.1 CRONBACHS ALPHA .................................................................................................................. 50 3.10.3.2 SPLIT HALF METHOD ................................................................................................................ 50

3.11 STATISTICAL METHODS ............................................................................................................. 51

3.12 QUALITATIVE APPROACH ......................................................................................................... 52

3.12.1 DATA ANALYSIS ......................................................................................................................... 52

3.13 EVALUATION OF THE METHODOLOGY ................................................................................ 52

3.14 DEVELOPING OF THE COMPARISON MODEL ...................................................................... 53

3.15 RESEARCH METHODOLOGY FLOW CHART ......................................................................... 53 CHAPTER (4) SUREVY ANALYSIS AND FINDINGS

4.1 INTRODUCTIONS ........................................................................................................................... 55

4.2 QUESTIONNAIRE ANALYSIS ...................................................................................................... 55

ix

4.2.1 PART ONE ....................................................................................................................................... 55 4.2.2 PART TWO ...................................................................................................................................... 59 4.2.3 PART THREE ................................................................................................................................... 63

4.3 STATISTICAL SIGNIFICANCES OF THE QUESTIONNAIRE COMPONENTS .................. 65

4.4 INTERVIEW ..................................................................................................................................... 72

4.4.1 INTERVIEW PROTOCOL .................................................................................................................. 72 4.4.2 INTERVIEW (1) ................................................................................................................................ 73 4.4.3 INTERVIEW (2) ................................................................................................................................ 73 4.4.4 INTERVIEW (3) ................................................................................................................................ 74 4.4.5 CONCLUSION OF INTERVIEWS ........................................................................................................ 74

CHAPTER (5) CASE STUDY

5.1 INTRODUCTION ............................................................................................................................. 76

5.2 PROJECT DATA .............................................................................................................................. 76

5.3 V.E TECHNICAL SUPPORTING TEAM ...................................................................................... 77

5.4 APPLICATION OF VALUE ENGINEERING STUDY ................................................................ 78

5.5 QUALITY MODEL........................................................................................................................... 79

5.6 COST ESTIMATE FOR MASTER FORMAT (BILL OF QUANTITIES ) ................................ 81

5.7 UNIFORMAT PRESENTATION FOR THE BILL OF QUANTITIES ...................................... 82

5.8 APPLICATION OF PARETO LAW ............................................................................................... 82

5.9 WORKSHOP STAGE ....................................................................................................................... 84

5.10 CREATIVITY PHASE ..................................................................................................................... 84

5.11 PRESENTATION OF THE PROPOSALS ..................................................................................... 85

5.11.1 PROPOSAL NO(1) ........................................................................................................................ 85 5.11.2 PROPOSAL NO. (2) ...................................................................................................................... 86 5.11.3 PROPOSAL NO (3) ....................................................................................................................... 89 5.11.4 PROPOSAL NO(4) ........................................................................................................................ 90 5.11.5 PROPOSAL NO (5) ....................................................................................................................... 91

5.12 SUMMARY OF COST SAVING FROM ALL PROPOSAL ........................................................ 92

CHAPTER SIX CONCLUSIONS AND RECOMMENDATIONS

6.1 INTRODUCTION ............................................................................................................................. 94

6.2 CONCLUSIONS ................................................................................................................................ 94

6.3 RECOMMENDATIONS .................................................................................................................. 95

References

ANNEX (1)Questionnaire

ANNEX (2)Standard Bill Of Quantities

ANNEX (3)Uniformat Bill Of Quantities

ANNEX (4)Drawings

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LIST OF FIGURES

No. Title

page

1.1: Research Conceptual Frame Work

5

2.1: The Value Engineering Elements

10

2.2: Potential influence of value during project phases

12

2.3: Worth versus Cost Graph

21

2.4: Value Engineering Methodology

24

2.5: VE Methodology

24

2.6: Elements used for cost analysis in RO plants

40

3.1: Methodology Flow Chart

53

4.1: Type of the Company or Organization of the Study Sample

56

4.2: Position in the Company or Organization Of The Study Sample

57

4.3: Experience in the field of water (years) of the study sample

58

4.4: Experience of the Company In The Field Of Water (Years)

58

4.5: Kind of Projects the Organization Is Working On Of the Study Sample

59

4.6: The presented weights and orders for the factors affecting the establishment of desalination plants

62

4.7: Orders, percentages, for all parties participations importance

64

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LIST OF TABLES

No. Title

page

2.1: Desalination Technologies and processes

27

2.2: Source Types Range from Beach Wells to Open-Ocean Intakes

34

2.3: Concentrate Disposal Cost

35

2.4: Operation and Maintenance Parameters for Desalination Plant

39

3.1: Questionnaire Scale

46

3.2: Correlation between Items of Factors Affecting The Establishment Of Desalination Plants & Total Degree Of The Domain

48

3.3: Correlation between Items of Parties Involved & Total Degree of Factor

49

3.4: Cronbachs alpha values for the Scale and its domain

51

4.1: The Results of Descriptive & Presented Weight for The Factors Affecting The Establishment of Desalination Plants

60

4.2: The suggested factors affecting the establishment of desalination plants

63

4. 3: One-way ANOVA for differences of factors importance and importance participation of parties in terms of the type of company

66

4.4: LSD Differences of Importance of Factors In Terms of Company Type

67

4. 5: One-Way ANOVA For Differences Of The Importance Of Factors And Importance Of Participation Of Parties In Terms Of The Position

67

4.6: One-way ANOVA for differences of factors importance and of participation of parties in terms of the experience in the field of water

69

4.7: One-way ANOVA for differences of the importance of factors & importance of parties participation in terms of organization experience in water

70

4.8: One-way ANOVA for differences of importance of factors & importance of parties participation in terms of project type in organization

71

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5.1: V.E Technical Support Team

78

5.2: The Main Quality Model Elements

80

5.3: Summary of Project Bill Of Quantities

81

5.4: Significant Part of the Unifromat Bill of Quantities

82

5.5: Summary of Recommended Proposals for The Bill Of Quantities

85

5.6 : Eliminated Items From Original BoQ Due to Redisgn of RO Unit

87

5.7 : Operation chemicals rates for pre-treatment process

88

5.8 : Yearly Operational Cost Saving from Redsign of RO Unit

89

5.9 : Tentative Power Demand Analysis for the Plant System

91

5.10 : Summary of Cost Saving from All Proposals 92

1

CHAPTER ONE

2

CHAPTER (1)

INTRODUCTION

1.1. BACKGROUND

Many regions of the world are facing formidable freshwater scarcity. The water resources

are very limited and the consumption rate is hugely increased over the last few years. Gaza

strip in particular suffering from shortage in the aquifer by 55 million cubic meters till

2017. (PWA, 2011)

With the light of the current political and economical circumstances, all relevant bodies

working in water sector agreed on adopting the construction of central desalination plant as

an exclusive solution to get over this problem (PWA, 2011)

However, the cost of construction of desalination plants projects have been rapidly increase

during the different plant life cycle. This may refer to different reasons which depend on

the project itself and /or other related circumstances; accordingly it was very important to

find an effective technique to face these phenomena which may be presented by value

engineering. (Durham, 2001)

1.2. RESEARCH PROBLEM

The value engineering technique is now being applied in most advanced countries in the

world, using these studies effectively by many international companies and institutions that

are specialized in various fields.

The concern of applying the concept of value engineering on the desalination plant project

refer to its clear effect to face the obstructions, whether in terms of technical or financial

issues, and thus the value engineering share significantly on the analysis of these

obstructions and then find the suitable solutions through saving various alternatives, with

keeping functions and features that the owner of product or project looks to achieve, such

as beauty, environment, safety, flexibility and other important factors.(Abdul-Fattaha and

Husseiny, 2001).

3

Moreover, it is significantly important to focus on applying this concept in desalination

plant in Gaza strip since Gaza is suffering from serious water consumption problems and in

bad need to establish new desalination plants to come over the huge shortage in water

production. (PWA, 2011)

Therefore, and due to the importance of applying this concept in the construction of

desalination plants in terms of cost reduction, this research will study the impact of

applying value Engineering on selected case study :Deir El Balah desalination plant by

identifying the most effective factors affecting water desalination in the plant in different

stages (planning, design, implantation and operation and maintenance) based on the

available information in this regard.

Obviously as Deir El Balah plant is already existing and operating, the first three stages

will be examined theoretically in comparison model to develop guidelines that may be

considered in establishing the central plant serving Gaza strip

Regarding the fourth stage (operation and maintenance) the research will evaluate the

possibility of any current corrective action that may be taken to expand the capacity of the

existing plant or decreases the unit cost production by applying value engineering in this

stage.

1.3. RESEARCH AIM

Contributing in resolving the water crisis in Gaza strip by considering the value engineering

concept as main factor affecting the cost of potable water production

1.4. RESEARCH OBJECTIVES

1. Identification of factors affecting the water desalination plant

2. Conducting "practical comparison model" for the cost reduction by applying the

value engineering concept on the selected case study (Deir El balah Desalination

plant).

4

1.5. JUSTIFICATION

Scientific significance of the research

There are many advantages related to the application of value engineering in projects, and

the most important of these advantages include:

1. The value engineering is considered from distinctive studies and capable of

providing a number of alternatives through the collective participation in the

brainstorm and evaluation it in order to reach the right decision.

2. Past experiences verified by using value engineering, the efficiency and control in

performance functionality and the projects costs.

3. The value engineering studies contribute in the direct link for the project parties and

approximate the different points of view through collective participation and

creative brainstorm.

4. Value engineering is not limited to one field or a particular area but also beyond to

the possibility of applying it in all areas, whether in the construction section,

agricultural, industrial, or as well as the administrative area.

5. The value studies contribute in the benefit of previous experience of implemented

projects or which have already been studied by avoiding errors which increase the

unjustified cost. (Al-Yousefi, Abdulaziz,2006).

1.6. PRACTICAL SIGNIFICANCE OF THE RESEARCH

The value engineering is new concept in the context of Gaza projects and practically not

applied in most of the implemented or planned projects.

Accordingly the application of this concept on the desalination plant may give guide for

other researcher to extent this application in other projects.

Moreover, the research may represent a valuable practice for the decision makers in the

process of adopting the best alternatives for the central desalination plant serving Gaza strip

in accordance to the master plant.

5

It will be tried to outline all predictable obstacles that may face the implementation of such

project in Gaza strip which will be an early alarm for donors and researcher in this context.

Also the research will be helpful for interested NGOs who are currently implementing

emergency small scale desalination units.

1.7. HYPOTHESIS

The cost of potable water production is lower when value engineering concept is applied in

constructing and operating the desalination plant

1.8. CONCEPTUAL FRAME WORK

Figure 1.1 indicated the main components of the conceptual frame work of the intended

study

Figure 1.1: Research Conceptual Frame Work

Affects And Guidlines For Central Deslalantion Plant

Contribution From, Pwa,cmwu And Ingo To Reach Practical Findings

Access For Adequate Data And Gathering Methodology

Level Of Knowledge And Interest Of VE Concept For Relevant Parties

PLANNING STAGE

DESIGN STAGE

CONSTRUCTION STAGE

OPERATION AND MAINTANENACE

6

CHAPTER TWO

7

CHAPTER (2)

LITERATURE REVIEW

A. PART ONE: VALUE ENGINEERING

2.1 INTRODUCTION

The methodology of value engineering is now being applied in most of the countries

which is the most advanced in the world, using these studies effectively by many

international companies and institutions that specialize in various fields.

Value engineering, is an analysis of the functions to identify and classify it and then

achieve those required functions by other creative methods that achieve the required

balance between the cost, functionality, performance, appearance and quality by

offering different alternatives, which means making rational changes to the design or

maybe going out with new design achieve the required functions with the highest

quality and lowest cost.

Most studies have indicated that the design phase accounts for 50% of the factors

affecting the cost while the owner only affects the cost by 10%. This is because the

owner is affected by the vision and analysis of others, such as the designer or the

consultant, and sometimes the owner imposes a certain perception which contributes

significantly to unjustified higher costs. Also the owner claims the knowledge and the

experience which makes him to intervene in the design works so he impose specific

ideas which are usually far from reality, such as simulation of designs or similar use of

materials not available or appropriate that fit with the local environment, and all that

under the context that the owner reserves the right to spend the money.(Al-Yousefi,

2006).

2.2 HISTORY OF VALUE ENGINEERING

Larry Miles an Engineer in General Electric Co. of America. Considered as the founder

of the value engineering technique worldwide.

8

In the first years after World War II, Miles was able to overcome at the acute shortage

of basic materials for manufacturing through the use of alternative materials and

designs while maintaining the different functions performed by the products to continue

production and meet commitments.

Miles then worked on the development of this approach between 1947 and 1952 in

order to bring improvement and development in a way of function analysis or

performance and not through the study of materials, parts, and he called it the

"functional analysis" (VA).

This method was a new step to improve and develop the products with reduction in

costs rather than the traditional method to reduce costs which often leads to reduction in

quality or performance level. Then this method moved to government institutions,

specifically the U.S. Navy (Jerjeas and Revay, 1999)

By early of 1961 the actual application was begun for value engineering protocol

through promotion of the various sectors from applying these studies, and followed that

by legislation the necessary laws, and also make training programs and introduction

workshops for value engineering methodology.

With the beginning of 1970, these studies have seen widespread in Japan, Europe,

India, passing to Australia.

As a natural result for these successful experiences and the growing interest in this

profession inside and outside the United States, professional organization has been

established concerning this profession, organized it and enact the necessary laws for

exercise it and exchange experiences.

This organization was called American Society of Value Engineering (SAVE), which

later became an international organization caring with the affairs of the profession

inside and outside the United States (SAVE-International), where the team work

consists of a group of specialists and experts in all fields and being on the top of this

team engineer value supported from the organization "( Al-Yousefi, 2006).

9

2.3 DEFINITION OF VALUE ENGINEERING

There are different names to Value Engineering studies as value analysis , value

engineering and value management , and all these with a single concept attach with the

methodology of the search about solutions and creative practical ideas that contribute in

overcoming many administrative and technical obstruction of the project through

searching for suitable alternatives and solutions working on raising quality and reducing

costs as well as the exceptional performance, taking into account conservation of the

functionality and the time factor.(Al-Yousefi, 2006)

It must be noted that there is a significant difference between the reduction of cost and

Value Engineering.

Value engineering is not simply about money its about value (Kirk et al 2002:5)

So its according to Hegan (1993) seeking to offer the client acost saving without

determinant to quality or performance .the power of the value engineering rooted in its

objective and disciplined methodology.

The reduction of cost is usually through the elimination of parts of the project and

hashed it to fit the available budget, but the value engineering is as already noted, it

aims to identify items that are not necessary according to functional analysis leading to

the exclusion of unnecessary costs, which usually cause an unjustifiable increase in

costs, accordingly we may hereby mention different definitions concluded in several

value engineering studies:-

"An organized collective effort directed to analyzing the functions of jobs and comply

them with the requirements of the beneficiary then to innovate alternatives to lead those

functions to the lowest or the most appropriate possible cost without compromising

quality and basic functions "( Al-Yousefi, 2006).

"An organized effort directed at analyzing the function of products and services to

achieve the desired functions and the essential characteristics at the best use of costs in

accordance with the wishes and expectations of the user". (SAVE International, 2011).

10

Accordingly, the main elements consisting the value engineering frame work is quality

,function and cost as indicated in Figure 2.1

Figure 2.1: The Value Engineering Elements, (Al-Yousefi, Abdulaziz, 2006)

2.4 VALUE METHODOLOGY APPLICABILITY

The possibility of applying the V.E. concept has wide range in several fields as

illustrated hereunder:

A. The Value Methodology can be applied wherever cost and/or performance

improvement is desired. That improvement can be measured in terms of monetary

aspects and/or other critical factors such as productivity, quality, time, energy,

environmental impact, and durability. VM can beneficially be applied to virtually all

areas of human endeavor

B. The Value Methodology is applicable to hardware, building or other construction

projects, and to soft areas such as manufacturing and construction processes, health

care and environment services, programming, management systems and organization

structure. The pre-study efforts for these soft types of projects utilizes standard

industrial engineering techniques such as flow charting, yield analysis, and value added

task analysis to gather essential data.

C. For civil, commercial and military engineering works such as buildings, highways,

factory construction, and water/sewage treatment plants, which tend to be one time

Value engineer

Quality

Cost Function

11

applications, VM is applied on a project to project basis. Since these are one-time

capital projects, VM must be applied as early in the design cycle as feasible to achieve

maximum benefits. Changes or redirection of design can be accomplished without

extensive redesign, large implementation cost, and schedule impacts. Typically for

large construction projects, specific value studies are conducted during the schematic

stage and then again at the design development (up to 45%) stage. Additional value

studies may be conducted during the construction or build phase.

D. For large or unique products and systems such as military electronics or specially

designed capital equipment, VM is applied during the design cycle to assure meeting of

goals and objectives. Typically a formalized value study is performed after preliminary

design approval but before release to the build/manufacture cycle. VM may also be

applied during the build/manufacture cycle to assure that the latest materials and

technology are utilized.

E. VM can also be applied during planning stages, and for project/program

management control by developing function models with assigned cost and

performance parameters. If specific functions show trends toward beyond control

limits, value studies are performed to assure the functions performance remains within

the control limits. (SAVE International, 1999)

2.5 VALUE ENGINEERING APPLICATIONS

VE application is of greatest benefits early in the development of a project with

improvement in value gained. Department of Housing and Works in the Government of

West Australia Value Management Guideline 2005, presented the potential influence of

Value Management according to Figure 2.2.

12

Figure 2.2: Potential influence of value during project phases, (Value Management

guidelines: 2005, West Australia)

2.6 PROCESS OF VALUE ENGINEERING APPLICATION

The process of Value engineering was described by several organization and VE

specialists. By going through these different methodologies we may find that all of

them agreed in the concept and main components of the process application , while

some of them like to merge some stages and others go in further detailed tasks and

activities .

Hereunder will explore the most common approaches in this concern

2.6.1 SAVE International Approach (1999)

The VM Job Plan covers three major periods of activity: Pre-Study, the Value Study,

and Post-Study. All phases and steps are performed sequentially. As a value study

progresses new data and information may cause the study team to return to earlier

phases or steps within a phase on an iterative basis. Conversely, phases or steps within

phases are not skipped.

13

2.6.1.1 Pre-Study

Preparation tasks involve six areas: Collecting/defining User/Customer wants and

needs, gathering a complete data file of the project, determining evaluation factors,

scoping the specific study, building appropriate models and determining the team

composition.

A. Collect User/Customer Attitudes

The User/Customer attitudes are compiled via an in-house focus group and/or

external market surveys. The objectives are to:

1. Determine the prime buying influence;

2. Define and rate the importance of features and characteristics of the product or

project;

3. Determine and rate the seriousness of user-perceived faults and complaints of

the product or project;

4. Compare the product or project with competition or through direct analogy with

similar products or projects.

For first time projects such as a new product or new construction, the analysis may

be tied to project goals and objectives.

The results of this task will be used to establish value mismatches in the

Information Phase.

B. Gather a Complete Data File

There are both Primary and Secondary sources of information. Primary sources are

of two varieties: people and documentation. People sources include marketing (or

the user), original designer, architect, cost or estimating group, maintenance or field

service, the builders (manufacturing, constructors, or systems designers), and

14

consultants. Documentation sources include drawings, project specifications, bid

documents and project plans.

Secondary sources include suppliers of similar products, literature such as

engineering and design standards, regulations, test results, failure reports, and trade

journals. Another major source is like or similar projects. Quantitative data is

desired.

Another secondary source is a site visitation by the value study team. Site

includes actual construction location, manufacturing line, or office location for a

new/improved system. If the actual site is not available, facilities with

comparable functions and activities may prove to be a valuable source of usable

information.

C. Determine Evaluation Factors

The team, as an important step in the process, determines what will be the criteria

for evaluation of ideas and the relative importance of each criteria to final

recommendations and decisions for change. These criteria and their importance are

discussed with the user/customer and management and concurrence obtained

D. Scope the Study

The team develops the scope statement for the specific study. This statement defines

the limits of the study based on the data-gathering tasks. The limits are the starting

point and the completion point of the study. Just as important, the scope statement

defines what is not included in the study. The scope statement must be verified by

the study sponsor.

E. Build Models

Based on the completion and agreement of the scope statement, the team may

compile models for further understanding of the study. These include such models

as Cost, Time, Energy, Flow Charts, and Distribution, as appropriate for each study.

15

F. Determine Team Composition, Wrap-Up

The Value Study Team Leader confirms the actual study schedule, location and

need for any support personnel. The study team composition is reviewed to assure

all necessary customer, technical, and management areas are represented. The

Team Leader assigns data gathering tasks to team members so all pertinent data will

be available for the study.

2.6.1.2 The Value Study

The value study is where the primary Value Methodology is applied. The effort is

composed of six phases: Information, Function Analysis, Creativity, Evaluation,

Development, and Presentation.

A. Information Phase

The objective of the Information Phase is to complete the value study data package

started in the Pre-Study work. If not done during the Pre-Study activities, the

project sponsor and/or designer brief the value study team, providing an opportunity

for the team to ask questions based on their data research. If a site visitation was

not possible during Pre-Study, it should be completed during this phase.

The study team agrees to the most appropriate targets for improvement such as

value, cost, performance, and schedule factors. These are reviewed with

appropriate management, such as the project manager, value study sponsor, and

designer, to obtain concurrence.

Finally, the scope statement is reviewed for any adjustments due to additional

information gathered during the Information Phase.

B. Function Analysis Phase

Function definition and analysis is the heart of Value Methodology. It is the

primary activity that separates Value Methodology from all other improvement

16

practices. The objective of this phase is to develop the most beneficial areas for

continuing study. The team performs the following steps:

1. Identify and define both work and sell functions of the product, project, or

process under study using active verbs and measurable nouns. This is often

referred to as Random Function Definition.

2. Classify the functions as basic or secondary,

3. Expand the functions identified in step 1 (optional),

4. Build a function Model - Function Hierarchy/Logic or Function Analysis

System Technique (FAST) diagram.

5. Assign cost and/or other measurement criteria to functions,

6. Establish worth of functions by assigning the previously established

user/customer attitudes to the functions,

7. Compare cost to worth of functions to establish the best opportunities for

improvement,

8. Assess functions for performance/schedule considerations,

9. Select functions for continued analysis,

10. Refine study scope,

17

C. Creative Phase

The objective of the Creative Phase (sometimes referred to as Speculation Phase) is

to develop a large quantity of ideas for performing each function selected for study.

This is a creative type of effort, totally unconstrained by habit, tradition, negative

attitudes, assumed restrictions, and specific criteria. No judgment or discussion

occurs during this activity. The quality of each idea will be developed in the next

phase, from the quantity generated in this phase.

There are two keys to successful speculation: first, the purpose of this phase is not

to conceive of ways to design a product or service, but to develop ways to perform

the functions selected for study. Secondly, creativity is a mental process in which

past experience is combined and recombined to form new combinations. The

purpose is to create new combinations which will perform the desired function at

less total cost and improved performance than was previously attainable.

There are numerous well accepted idea generation techniques. The guiding

principle in all of them is that judgment/evaluation is suspended. Free flow of

thoughts and ideas - without criticism - is required.

D. Evaluation Phase

The objectives of the Evaluation Phase are to synthesize ideas and concepts

generated in the Creative Phase and to select feasible ideas for development into

specific value improvement.

Using the evaluation criteria established during the Pre-Study effort, ideas are

sorted and rated as to how well they meet those criteria. The process typically

involves several steps:

1. Eliminate nonsense or thought-provoker ideas,

2. Group similar ideas by category within long term and short term implications.

Examples of groupings are electrical, mechanical, structural, materials, special

processes, etc,

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3. Have one team member agree to champion each idea during further

discussions and evaluations. If no team member so volunteers, the idea or

concept is dropped,

4. List the advantages and disadvantages of each idea,

5. Rank the ideas within each category according to the prioritized evaluation

criteria using such techniques as indexing, numerical evaluation, and team

consensus,

6. If competing combinations still exist, use matrix analysis to rank mutually

exclusive ideas satisfying the same function,

7. Select ideas for development of value improvement,

If none of the final combinations appear to satisfactorily meet the criteria, the value

study team returns to the Creative Phase.

E. Development Phase

The objective of the Development Phase is to select and prepare the best

alternative(s) for improving value. The data package prepared by the champion of

each of the alternatives should provide as much technical, cost, and schedule

information as practical so the designer and project sponsor(s) may make an initial

assessment concerning their feasibility for implementation. The following steps are

included:

1. Beginning with the highest ranked value alternatives, develop a benefit analysis

and implementation requirements, including estimated initial costs, life cycle

costs, and implementation costs taking into account risk and uncertainty,

2. Conduct performance benefit analysis,

3. Compile technical data package for each proposed alternative,

a. written descriptions of original design and proposed alternative(s),

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b. sketches of original design and proposed alternative(s),

c. cost and performance data, clearly showing the differences between the

original design and proposed alternative(s),

d. any technical back-up data such as information sources, calculations, and

literature,

e. schedule impact,

4. Prepare an implementation Plan, including proposed schedule of all

implementation activities, team assignments and management requirements.

5. Complete recommendations including any unique conditions to the project

under study such as emerging technology, political concerns, impact on other

ongoing projects, marketing plans, etc.

F. Presentation Phase

The objective of the Presentation Phase is to obtain concurrence and a commitment

from the designer, project sponsor, and other management to proceed with

implementation of the recommendations. This involves an initial oral presentation

followed by a complete written report.

As the last task within a value study, the VM study team presents its

recommendations to the decision making body. Through the presentation and its

interactive discussions, the team obtains either approval to proceed with

implementation, or direction for additional information needed.

The written report documents the alternatives proposed with supporting data, and

confirms the implementation plan accepted by management. Specific organization

of the report is unique to each study and organization requirements.

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2.6.1.3 Post Study

The objective during Post-Study activities is to assure the implementation of the

approved value study change recommendations. Assignments are made either to

individuals within the VM study team, or by management to other individuals, to

complete the tasks associated with the approved implementation plan.

While the VM Team Leader may track the progress of implementation, in all cases the

design professional is responsible for the implementation. Each alternative must be

independently designed and confirmed, including contractual changes if required,

before its implementation into the product, project, process or procedure. Further, it is

recommended that appropriate financial departments (accounting, auditing, etc.)

conduct a post audit to verify to management the full benefits resulting from the value

methodology study. Further, it is recommended that appropriate financial departments

(accounting, auditing, etc.) conduct a post audit to verify to management the full

benefits resulting from the value methodology study.

2.6.2 Value Management

The Department of Housing and Works in Western Australia developed value

management guidelines. It almost has the same steps for VE methodology as SAVE Int.

methodology.

The steps of Value Management process are:

1. Information Phase: essentially preparatory work for the study, including items

such as the development of objectives, key issues and concerns, background

information, key assumptions, cost overview and study scope.

2. Analysis Phase: includes functional analysis, establishing system links, testing

parameters and rationalizing data.

3. Creative Phase: is predominantly concerned with encouraging divergent ideas,

lateral thinking and brainstorming, and generating alternatives for better value

alternatives.

4. Evaluation Phase: ideas are assessed, culled and prioritized to identify viable

alternatives.

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5. Development and Reporting Phase: options and rationale are refined and

documented into action plans for recommendation to the project decision maker.

2.6.3 Acquisition Logistics Engineering.

Acquisition Logistics Engineering (ALE) presented the Value Engineering six

phases job Plan as The Department of Housing and Works in Western Australia did

with addition of Implementation Phase and with some differences. ALE

methodology steps are:

1. Information Phase: in addition to gathering information, ALE added that VE

team establishes the areas that will allow for the most improvement and isolates

the major cost items.

2. Function Analysis Phase: sometimes it is performed within information phase.

FAST model is developed as well as cost and cost worth models. An initial

assessment is done to find mismatch between cost and value. This can be shown

graphically by plotting each item's worth versus cost percentage as shown in

Figure below where the numbers in the circles represents the value index of

functions. (El Sadawi, 2008)

Figure 2.3:Worth Versus Cost Graph, (El Sadawi, 2008)

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3. Creative Phase: in this phase, team brainstorming identifies many alternative

ways of performing the functions of the candidate items having the greatest

worth/cost mismatch.

4. Evaluation Phase: a first cut through alternatives should eliminate impractical or

unfeasible alternatives. Advantages and disadvantages of each alternative in

addition to cost are concluded. If every alternative is eliminated during this

phase, the team must return to the creative phase.

5. Development Phase: the remaining alternatives are refined and developed into a

value engineering proposals including detailed description of the alternatives

including benefits in terms of cost and performance.

6. Implementation Phase: it is sometimes broken into two parts, one for

presentation, and approval and the other for formal implementation.

2.6.4 Caldwell

Caldwell (2006) methodology is composed of the following phases:

1. Information Phase: presentation is made to the VE team to explain the main

concepts of the design. This includes project objectives, design constrains,

drawings, specifications, the special conditions and the estimated cost. Caldwell

prefers that those who present the information should not be part of the VE team.

2. Function Analysis: in this phase major project components are identified as well

as their functions and estimated cost.

3. Speculation: during the speculation phase, the VE team considers each design

component and suggests alternative means of accomplishing the function of the

component. Brainstorming is the most suitable technique.

4. Alternative Comparison: this phase is done to define comparison criteria so that

alternatives can be compared. This phase is preferred to be performed using

brainstorming initially and then through a detailed definitions of each criteria

Weights of criteria are developed by VE Team.

5. Analysis: analyzing alternatives involves comparing them to the criteria. Each

team participant numerically evaluates each alternative against a specific

23

criterion. Scores may vary from 1 to 5 with 1 identified as poor and 5 is very

good.

6. Concept Development: during the concept development phase, the concept

selected by the VE team is organized and refined before presentation to the

owner. Sketches may be prepared or a narrative report compiled. Cost estimates

may be refined.

7. Presentation and Implementation: in the presentation/implementation phase, VE

recommendations are presented to the client, owner, or project manager who is

sponsoring the project. The project manager decides whether the VE

recommendations should be incorporated into remedial action.

8. Report: depending on the budget, topic, and significance of the VE workshop, a

formal report may be prepared. Generally the most cost-effective method is to

have the flipcharts photo-reproduced, copied, collated, and distributed. This

provides a full record of deliberations, scores, recommendations, etc.

Caldwell elaborates the criteria for both the facilitator of the job plan and the

participants as follows:

a. The Facilitator

The facilitator should be chosen with care. He is not required to have specific

knowledge of the project or even of the technologies involved. His role is simply to

act as a neutral presence and to make certain that the workshop is conducted in

accordance with standard VE procedures.

b. Participants

The number of participants is between five and twelve. Never let the number of

participants rise above twelve. There should be a balance of senior and mid-level

experience. The majority should be well versed in the technology being examined.

Caldwell presents VE methodology in Figure 2.4

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Figure 2.4:ValueEngineering Methodology, (Caldwell,2006)

2.6.5 Dell'Isola

DellIsola method is described simply in Figure 2.5, which presents a schematic

flow chart for the methodology of applying VE concept

Figure 2.5: VE Methodology, (Dell'Isola, 1998)

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B. PART TWO: WATER DESALINATION

As the research will extrapolate the impact of applying value engineering in existing

desalination plant in Gaza, it will be essential to provide an intensive overview on

desalination literature related to the application of value engineering.

Therefore, the presented literature hereunder will focus mainly on the importance

factors affecting the quality, cost and function in desalination plants.

2.7 HISTORY OF DESALINATION

Obviously Desalination can be considered as a natural phenomenon through natural

distillation cycle of water evaporating from the sea and then condensing to form Pure

rain water, also there is other kind of natural occurrences leaded to desalination such as

freezing of seawater near the polar region. Where The ice crystals formed are pure

water, the salt being excluded from participation in the crystal growth.

However, since the turn of the century, necessity has driven scientists and engineers to

utilize desalination technology of varying effectiveness to produce pure water from

saline water. (Al-Shayji, 1998)

With the development of temperature and pressure measurements, together with an

understanding of the properties of gases, land desalination began to play an important

role.

The first commercial land-based seawater desalination plant was installed by the

Ottomans in Jeddah, Saudi Arabia. This crude distillation unit was a boiler working

under atmospheric pressure, but this unit suffered from severe scale deposits and

corrosion problems. It is now part of a historical monument on Jeddah Corniche.

With the improvement in submerged-tube technology, the first evaporators with a total

capacity in excess of 45,000 m3/d were built in Kuwait Curacao in the early 1950s.

But it was not until the development of the multistage flash distillation method by

Professor Robert Silver in the 1950s, when the research and development of saline

water conversion was promoted, that desalination became a practical solution to the

shortage of drinking water.

The historical turning point in the history of desalination is the introduction of multi

stage flash desalination (MSF) in Kuwait in 1957. The Kuwait Department of

26

Electricity and Water placed an order with Westinghouse for four 0.5-million-gallon-

per-day (MGD),evaporator units each with four stages, designed by Rowland Colte.

Their success encouraged the authority in Kuwait to go for larger and more efficient

desalination units, and to accept an offer from G and J Weir to supply a new

desalination concept known as the Multistage Flash.

The innovator of the multistage flash system was Professor Robert Silver. Although he

held patents on the process both in Europe and the USA, he never received any

financial rewarded for his work.

With this success, companies all over the world, especially in the USA and the UK,

undertake extensive research and development on large flash-type evaporator units to

achieve lower production cost.

The installation of similar evaporators manufactured by other contractors followed the

great success of flash evaporation. Subsequently, Sasakura installed the first 5 million

gallon-per-day MSF units at Shuwaikh in Kuwait. Similar units were then installed in

the new Kuwait plants located at Shuiabah. The success of these large units, proving

that the MSF process could produce water economically and with greater reliability

than previous systems, set the stage for the great advances in desalination capacity that

were to follow in the 1970-1980s (Temperly, 1995).

In 1953, Reid, C. E. and Breton, E. J. at the University of Florida proposed a research

program to the Office of Saline Water (OSW). They developed a membrane that was

made of a cellular acetate material and had the ability to reject salt. However, the water

flux through the dense membrane was too low to have commercial significance.

The major breakthrough in membrane development came in a parallel research

program,

from 1958 to 1960, at the University of California at Los Angeles (UCLA) where

S.Leob, and S. Sourirajan were credited with making the first high-performance

membranes by creating an asymmetric cellulose acetate structure with improved salt

rejection and water flux.

In 1965, the UCLA team installed the first municipal reverse osmosis plant in Coalinga,

California. The plant was desalting water containing 2,500 ppm salts, and

producing5,000 GPD with a tubular cellular acetate membrane. The development of the

27

tubular, spiral-wound, and hollow-fine-fiber modules together with the development of

the polyamide membranes takes place from 1965-1970.

Through the 1980s, improvements were made to these membranes to increase water

flux and salt rejection with both brackish water and seawater. Brackish water is water

that contains dissolved matter at an approximate concentration range from 1,000-35,000

mg/l. (Al-Shayji,1998)

2.8 DESALINATION TECHNOLOGIES

A desalination process essentially separates saline water into two parts - one that has a

low concentration of salt (treated water or product water), and the other with a much

higher concentration than the original feed water, usually referred to as brine

concentrate or simply as concentrate.

The two major types of technologies that are used around the world for desalination can

be broadly classified as either thermal or membrane. Both technologies need energy to

operate and produce fresh water. Within those two broad types, there are sub-categories

(processes) using different techniques. The major desalination processes are identified

in Table 2.1.

Table 2.1: Desalination Technologies and Processes

Thermal and membrane capacity on a worldwide basis was about 7 billion gallons per

day (bgd) in early 2000, with about 50% in thermal processes and 50% in membrane

technologies. This is total installed capacity since the early 1950s, and not all of that

capacity may be in operation. On a global basis, desalination capacity increased at

almost 12 percent per year, from 1972 through 1999. There have been over 8,600

desalination plants installed worldwide, with approximately 20 percent of them in the

Thermal Technology Membrane Technology

Multi-Stage Flash Distillation (MSF) Electrodialysis (ED)

Multi-Effect Distillation (MED) Electrodialysis reversal (EDR)

Vapor Compression Distillation (VCD) Reverse Osmosis (RO)

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U.S., the largest number of any country in the world. In terms of capacity however, the

U.S. ranks second globally (U.S Ministry of Interior, 2003).

2.8.1 Thermal Technologies

Thermal technologies, as the name implies, involve the heating of saline water and

collecting the condensed vapor (distillate) to produce pure water. Thermal technologies

have rarely been used for brackish water desalination, because of the high costs

involved. They have however been used for seawater desalination and can be sub-

divided into three groups: Multi-Stage Flash Distillation (MSF), Multi-Effect

Distillation (MED), and Vapor Compression Distillation (VCD).

2.8.2 Multi-Stage Flash Distillation (MSF)

This process involves the use of distillation through several (multi-stage) chambers. In

the MSF process, each successive stage of the plant operates at progressively lower

pressures. The feed water is first heated under high pressure, and is led into the first

flash chamber, where the pressure is released, causing the water to boil rapidly

resulting in sudden evaporation or flashing. This flashing of a portion of the feed

continues in each successive stage, because the pressure at each stage is lower than in

the previous stage. The vapor generated by the flashing is converted into fresh water by

being condensed on heat exchanger tubing that run through each stage. The tubes are

cooled by the incoming cooler feed water. Generally, only a small percentage of the

feed water is converted into vapor and condensed.

Multi-stage flash distillation plants have been built since the late 1950s. Some MSF

plants can contain from 15 to 25 stages, but are usually no larger than 15 mgd in

capacity. MSF distillation plants can have either a once-through or recycled process.

In the once-through design, the feed water is passed through the heater and flash

chambers just once and disposed of, while in the recycled design, the feed water for

cooling is recycled. Each of these processes can be structured as a long tube or cross

tube design. In the long tube design (built at Freeport in 1961), tubing is parallel to the

concentrate flow, while in the cross tube design, tubing is perpendicular to the

concentrate flow.

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MSF plants are subject to corrosion unless stainless steel is used extensively. In

addition to corrosion, MSF plants are also subject to erosion and impingement attack

(U.S. Bureau of Reclamation, 2003). Erosion is caused by the turbulence of the feed

water in the flash chamber, when the feed water passes from one stage to another.

Distillation processes produce about 3.4 billion gpd globally, which is about 50 percent

of the worldwide desalination capacity. MSF plants provide about 84 percent of that

capacity. Most of those plants have been built overseas, primarily in the Middle East,

where energy resources have been plentiful and inexpensive.

2.8.3 Multi-Effect Distillation (MED)

The MED process has been used since the late 1950s and early 1960s. Multi-effect

distillation occurs in a series of vessels (effects) and uses the principles of evaporation

and condensation at reduced ambient pressure. In MED, a series of evaporator effects

produce water at progressively lower pressures. Water boils at lower temperatures as

pressure decreases, so the water vapor of the first vessel or effect serves as the heating

medium for the second, and so on. The more vessels or effects there are, the higher the

performance ratio. Depending upon the arrangement of the heat exchanger tubing,

MED units could be classified as horizontal tube, vertical tube or vertically stacked tube

bundles

There have been several MED plants built in the U.S. and overseas. Three low-

temperature MED plants with a combined capacity of 3.5 mgd have been operating

successfully in St. Thomas, U.S. Virgin Islands, where desalinated water is the principal

water supply source (Krishna, 1989). The MED units are operated by the Virgin Islands

Water and Power Authority. Steam from the power plant is directed to the evaporators

in the desalination units. Product water is obtained as condensate of the vapor from

each vessel. Several MED plants are found overseas, both in the Caribbean and in the

Middle East.

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2.8.4 Vapor Compression Distillation

The vapor compression distillation (VCD) process is used either in combination with

other processes such as the MED, or by itself. The heat for evaporating the water comes

from the compression of vapor, rather than the direct exchange of heat from steam

produced in a boiler (Buros, 2000). Vapor compression (VC) units have been built in a

variety of configurations. Usually, a mechanical compressor is used to generate the heat

for evaporation. The VC units are generally small in capacity, and are often used at

hotels, resorts and in industrial applications.

2.8.5 Membrane Technologies

Membrane technologies can be subdivided into two broad categories: Electro

dialyis/Electro dialysis Reversal (ED/EDR), and Reverse Osmosis (RO).

2.8.5.1 Electro dialysis (ED) and Electro dialysis Reversal (EDR)

Electro dialysis (ED) is a voltage-driven membrane process. An electrical potential is

used to move salts through a membrane, leaving fresh water behind as product water.

ED was commercially introduced in the 1960s, about 10 years before reverse osmosis

(RO), Although ED was originally conceived as a seawater desalination process, it has

generally been used for brackish water desalination.

ED depends on the following general principles:

- Most salts dissolved in water are ions, either positively charged (cations), or

negatively charged (anions).

- Since like poles repel each other and unlike poles attract, the ions migrate toward the

electrodes with an opposite electric charge

- Suitable membranes can be constructed to permit selective passage of either anions or

cations.

In a saline solution, dissolved ions such as sodium (+) and chloride (-) migrate to the

opposite electrodes passing through selected membranes that either allow cations or

anions to pass through (not both). Membranes are usually arranged in an alternate

pattern, with anion-selective membrane followed by a cation-selective membrane.

During this process, the salt content of the water channel is diluted, while concentrated

31

solutions are formed at the electrodes. Concentrated and diluted solutions are created in

the spaces between the alternating membranes, and these spaces bound by two

membranes are called cells. ED units consist of several hundred cells bound together

with electrodes, and is referred to as a stack. Feed water passes through all the cells

simultaneously to provide a continuous flow of desalinated water and a steady stream of

concentrate (brine) from the stack.

In the early 1970s, the Electro dialysis Reversal (EDR) process was introduced (Buros,

2000). An EDR unit operates on the same general principle as an ED unit, except that

both the product and concentrate channels are identical in construction. At intervals of

several times an hour, the polarity of the electrodes is reversed, causing ions to be

attracted in the opposite direction across the membranes. Immediately following

reversal, the product water is removed until the lines are flushed out and desired water

quality restored. The flush takes just a few minutes before resuming water production.

The reversal process is useful in breaking up and flushing out scales, slimes, and other

deposits in the cells before they build up. Flushing helps in reducing the problem of

membrane fouling.

Because of the inherent characteristics of the electrical process used in ED units, they

are normally used to desalinate brackish water, rather than high salinity water such as

seawater. The few ED units that are located in Texas are those that are used in low-

salinity applications such as surface water desalination (Lake Granbury and Sherman,

2001).

2.8.5.2 Reverse Osmosis (RO) and Nano filtration (NF)

In relation to thermal processes, Reverse Osmosis (RO) is a relatively new process that

was commercialized in the 1970s (Buros, 2000). Currently, RO is the most widely used

method for desalination in the United States. The RO process uses pressure as the

driving force to push saline water through a semi-permeable membrane into a product

water stream and a concentrated brine stream. Nano filtration (NF) is also a membrane

process that is used for removal of divalent salt ions such as Calcium, Magnesium, and

Sulphate. RO, on the other hand, is used for removal of Sodium and Chloride. RO

processes are used for desalinating brackish water (TDS>1,500 mg/l), and seawater.

32

Osmosis is a natural phenomenon by which water from a low salt concentration passes

into a more concentrated solution through a semi-permeable membrane. When pressure

is applied to the solution with the higher salt concentration solution, the water will flow

in a reverse direction through the semi-permeable membrane, leaving the salt behind.

This is known as the Reverse Osmosis process or RO process.

An RO desalination plant essentially consists of four major systems:

a) Pretreatment system,

b) High-pressure pumps,

c) Membrane systems,

d) Post-treatment.

Pre-treatment is very important in RO because the membrane surfaces must remain

clean. Therefore, all suspended solids must be first removed, and the water pre-treated

so that salt precipitation or microbial growth does not occur on the membranes. Pre-

treatment may involve conventional methods such as a chemical feed followed by

coagulation/flocculation/sedimentation, and sand filtration, or pre-treatment may

involve membrane processes such as microfiltration (MF) and ultrafiltration (UF). The

choice of a particular pre-treatment process is based on a number of factors such as feed

water quality characteristics, space availability, RO membrane requirements, etc.

High pressure pumps supply the pressure needed to enable the water to pass through the

membrane and have the salt rejected. The pressures range from about 150 psi for

slightly brackish water to 800 - 1,000 psi for seawater.

The membrane assembly consists of a pressure vessel and a semi-permeable membrane

inside that permits the feed water to pass through it. RO membranes for desalination

generally come in two types: Spiral wound and Hollow fiber. Spiral wound elements

are actually constructed from flat sheet membranes. Membrane materials may be made

of cellulose acetate or of other composite polymers. In the spiral wound design, the

membrane envelope is wrapped around a central collecting tube. The feed water under

pressure, flows in a spiral path within the membrane envelope, and pure (desalinated)

water is collected in the central tube. As a portion of the water passes through the

membrane, the remaining feed water increases in salt content. A portion of the feed

water is discharged without passing through the membrane. Without this discharge, the

33

pressurized feed water would continue to increase in salinity content, causing super-

saturation of salts. The amount of feed water that is discharged as concentrate ranges

from about 20 percent for brackish water to about 50 percent for seawater (Krishna,

1989).

2.9 FACTORS AFFECTING COST OF DESALINATION

Cost is sensitive issue which affects the decision makers preferable and selections;

however each technology may have its own characteristics in terms of resources, design

aspects and other direct and indirect cost parameters.

As the adopted technology in intended case study and the planned central desalination

plant in Gaza strip is the sea water reverse osmosis, we will highlight herewith the most

effective factors affecting the cost terminology (Water reuse Association Desalination

Committee, 2012)

2.9.1 Selection of Intake and Concentrate Discharge

Feed water intake configuration directly affects capital and operational costs of the

treatment process. Without consideration for the cost of land associated with each

option, beach well intakes are usually less costly on an equipment basis. However, once

land acquisition and easements are factored into the process, this intake type is typically

40 to 50%more costly than an open intake of similar capacity. Horizontal and slant

wells are comparable to open intake (yet more costly than co-located open intakes using

existing infrastructure), and infiltration galleries typically cost more than open intakes.

Of all the intake options, only open intakes have the longest-running installation history

and reliability necessary to support the full-scale development of a large desalination

facility at a new site. As a result, there is a significant depth of understanding related to

the costs associated with constructing open intakes as well as the associated discharge

pipeline.

Few SWRO facilities exist employing an intake type differing from the conventional

open-intake. This lack of available installations for use as a qualitative benchmark for

costing same-site alternatives is important for planners and engineers focused on

process considerations and/or cost comparisons. However, published information is

34

limited and can be site-specific. Generalized guidance is contained in Table 2.2: Source

types range from beach wells to open-ocean intakes (Water Reuse Association, 2012)

Table 2.2: Source Types Range from Beach Wells to Open-Ocean Intakes

Various methods are available to dispose of the concentrate stream, and the availability

of alternatives will vary due to many site-specific variables. With that consideration,

conveyance alternatives and a range of costs associated with each alternative are

contained in Table 2.3 The costs do not include conveyance attributable to connecting

the desalination plant to the disposal location (in the case of discharge to the ocean, this

would be from the desalination plant to the shore line) because the conveyance distance,

terrain, and associated costs are site-specific and highly variable, and this conveyance

cost can dominate disposal costs.

35

Table 2.3: Concentrate Disposal Cost

By comparison, most of the desalination plants yielding the lowest water production

costs have concentrate discharges either located in coastal areas with very intensive

natural mixing or are combined with power plant outfall structures which use the

buoyancy of the warm power plant cooling water to provide accelerated initial mixing

and salinity plume dissipation at lower cost. The intake and discharge facility costs for

these plants are usually less than 10% of the total desalination plant costs.

2.9.2 Feed and Finished Water Quality

The type of pretreatment system and type of pretreatment technology selected are very

dependent on the feed water quality. Because open ocean feed water (compared with

well water, for example) will typically contain a greater level of suspended material and

impurities that could possibly foul a reverse osmosis membrane, the capability of the

pretreatment necessary to suitably pre-condition the feed water is crucial to ensure a

long, sustainable membrane service life. For example, some coastal well water supplies

and certain open ocean sources are generally expected to contain very low levels of

foulants and particulates; therefore, a lesser-degree of pretreatment may be warranted. It

is important to keep this point in context, because suspended material content (e.g.,

iron, sulfur, manganese) of coastal ocean locations is sitespecific and could eliminate

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the potential benefit of a lesser-degree of pretreatment and the associated capital and

operational costs.(Water Reuse Association Desalination Committee, 2011)

Additionally, as with any seawater desalination project, the feed water temperature,

source water "cleanliness (such as suspended biomass or turbidity), and ambient

salinity fluctuations also affect project costs. For example, if a SWRO facility planned

along the one location coast treats seawater that is on average 10 degrees colder than a

SWRO facility located in second location , the necessary feed pressure would increase

10 to 15% over the warmer water to achieve the equivalent production value, thereby

increasing energy consumption and associated operating costs.

Lower range of costs represents a single stage, single pass SWRO system which is

capable of reliably meeting a TDS of less than 450 mg/L. Individual analytic

concentration limitations such as boron or chloride (for horticultural water quality

purposes) can also affect costs, because at very low concentration limits an additional

membrane treatment step might be necessary. If this is the case, additional costs

associated with producing a lower TDS product water will increase from 15 to 30% of

the cost of the single stage, single pass system (Water Reuse Association Desalination

Committee, 2012)

2.9.3 Distribution

Throughput (or production) capacity of a desalination facility (as with any other type

of production facility)affects the size and number of the equipment needed, as well as

the space necessary to locate a treatment plant. Coastal communities utilizing

desalination as a source of drinking water are usually in close proximity to the

treatment facility; therefore, land is usually priced at a premium. The cost of locating a

facility closer to the point of use and a suitable power source should be weighed against

the costs associated with additional intake and discharge pipeline easements,

transmission line costs, materials used for construction, permits, labor, and maintenance

associated with moving a plant farther away from an intake/discharge or distribution

service area(ShankerMuraleedaran,2009).

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2.9.4 Permitting and Regulatory Issues

The regulatory landscape differs vastly in the communities served by desalination

facilities. These differences can have a profound impact on project delivery timelines,

legal costs, and in some cases alter the design of the SWRO facility. Without question,

each country has its own set of environmental criteria which must be met by any single

project. In consideration of laws in the United States, each State and region has its own

set of rules, regulations, and standards, all of which conform to federal laws and

guidelines while potentially being more restrictive, and usually related to site-specific

nuances (Shanker Muraleedaran, 2009).

2.9.5 Project Delivery Mechanism

Number of project delivery methods and financing tools has proven to be successful in

the SWRO desalination industry. The size of the project, expected contract duration,

location, competition, risk allocation, and project (owner) preferences all dictate by

what means the project is delivered. For example, the combination of large capacity

SWRO facilities, enhanced competition, and owner preferences for low risk have

enabled the design- build- own- operate (DBOOT) project delivery community to

commission SWRO projects , Without exception, the lowest cost desalination projects

to date have been delivered under turnkey DBOOT contracts where private sector

developers or consortia share risks with the public sector based to their ability to control

and mitigate the respective project related risks. A contributing cause to the lower costs

is that the insurance and contingencies in DBOOT contracts are between 10 and 20% of

the tot