Most Effective Micro Organisms In Propeller Fouling

Description

ABSTRACT

Marine propellers with complex shaped surface could not satisfy hydrodynamics and have complex flow-structure interactions during running. While marine organisms are obstacles when ship propellers keep propulsion efficiency, many of them have been coated with fouling release coating to maintain propeller propulsion efficiency. In this paper, the most effective microorganism that attacks ship propeller shall be studied and analyzed. In the above context, tests for microorganism were carried out. Open water tests showed the microorganism significantly affect thrust and torque characteristics of model propeller. After the use on ship propellers for a period of 16 months, composite coating matched well only with minor damage on the leading edge, but none diffusion under the coating layer. And also marine organisms on blades of propeller could be washed away easily with high pressure water.

TABLE OF CONTENTS

COVER PAGE

TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

CHAPTER ONE

1.0      INTRODUCTION

• BACKGROUND OF THE STUDY
• PROBLEM STATEMENT
• AIM OF THE STUDY
• OBJECTIVE OF THE STUDY
• SCOPE OF THE STUDY
• PURPOSE OF THE STUDY
• HYPOTHESIS
• SIGNIFICANCE OF THE STUDY
• LIMITATION OF THE STUDY
• RESEARCH QUESTIONS
• DEFINTION OF TERMS
• PROJECT ORGANISATION

CHAPTER TWO

LITERATURE REVIEW

• OVERVIEW OF THE STUDY
• OVERVIEW OF BIOFOULING
• IMPACT OF MARINE BIOFOULING
• DETECTION OF SHIP BIOFOULING
• DESCRIPTIONAL REVIEW OF ANTI-FOULING
• HISTORICAL BACKGROUND OF BIOFOULING
• EMPIRICAL STUDY OF BIOFOULING
• OVERVIEW OF MICROORGANISM
• TYPES OF MICROORGANISMS

CHAPTER THREE

METHODOLOGY

• EXPERIMENTAL METHOD AND MATERIALS

CHAPTER FOUR

• RESULT AND DISCUSSION

CHAPTER FIVE

• CONCLUSION
• RECOMMENDATION
• REFERENCES

CHAPTER ONE

1.0                                          INTRODUCTION

1.1                            BACKGROUND OF THE STUDY

A propeller is a type of fan that transmits power by converting rotational motion into thrust, which is the power unit of a ship. As the pressure difference is  produced between the  forward and rear surfaces of the airfoil-shaped blade, and water is accelerated behind the blade [Carlton J, 2007].

The propellers operated at high rotational speed or under heavy load accelerate poop flow rate, coupled with the high-speed flow around. Water is too late to fill the front of the blades after thrown around; the pressure on the upstream surface of the blade can drop below the vapor pressure of the water, and result in the formation of a vapor pocket.

High performance of propellers should conquer cavitation erosion[Lichtman J Z, 1961] and fouling [1992  Pat US 5080926], both of them contributing to speed declining and fuel consumption increasing [Schultz M, 2007].

Marine fouling [Callow E M, 2002] ranges from micro-fouling (bacterium, algae, slime etc) to macro-fouling (microalgae, soft bodied and hard shelled). Attachment of marine fouling organisms is a very complex process [Chambers L D, 2006], which beginning with slime, and finally to macro-fouling. Copper alloy substrate of propeller immerse in the water, give the surface of  black oxide  film which providing breeding grounds for the attachment of marine organisms. In  the  process  seaweed,  sea  squirts, barnacles  and  other marine creatures gradually adhere to the surface of propeller in  large  quantity  which  contribute  to weight and roughness of ship hulls which reducing their propulsive efficiency. Unpredictable fuel consumption was made up for a loss of marine organisms. As reported in British Ship Research association, surface area of propeller is not big, but it is very huge in energy loss that cavitations and fouling brought [Aktas B, 2016]. For example, to a container ship of  around  3000TEU  traveling  with  a  speed about 23 kn, the energy loss caused by corrosion for propeller reached to 6%, almost  one-third of  the  total loss [Anderson C, 2003]. Also fouling on propellers of blades gives uneven blade with different weight which increasing drag torque. All of these bring enormous economic and security risks.

Till date, the most effective method is self-polishing co-polymer technology with various toxic compounds, but the shipping community is forced to review their anti-fouling policies to meet the tougher environmental regulations. So a completely environmental friendly antifouling technology (silicone coating known as “fouling release” property) [Anderson C, 2003] was introduced in the early 1990s. It  is through hydrodynamic shear forces to control the attachment of marine organisms rather  than killing them in various ways. After that, many different fouling release  coating  has  been  developed  which result in more and more applications for ship hulls and propellers. Within the above context, the experimental study in this paper developed an analysis of most effective microorganism in a ship propeller fouling.

1.2                                                 PROBLEM STATEMENT

When the ship propeller is infected by microorganisms, it creates shock wave and hence cavitation noise; which affect the sleep of sailors, and also contributes to speed declining and fuel consumption increasing in a ship during sailing. This study was written to make the reader familiar with such microorganisms responsible in attacking the propeller.

1.3                                                   AIM OF THE STUDY

This study aimed at isolating, identifying and counting bacterial and fungal contaminants on water most especially the one that affect ship propeller most.

1.4                                              PURPOSE OF THE STUDY

The purpose of the present study was to carry out the test of micro-organism associated with ship propeller.

1.5                                             OBJECTIVE OF THE STUDY

At the end of this work student involved shall be able to:

1. Identify microorganisms associated with ship propeller.
2. Understand the meaning of microorganisms

• The effect of microorganism on ship propeller

1. How ship propeller can be protected from microorganism.

1.6                                           HYPOTHESIS

HO:   Microbial organisms are identified in ship propeller.

Hg     = Microorganisms are not identified in ship propeller

1.7                             SIGNIFICANCE OF THE STUDY

This study will be useful to ship sailors and the producers of ships.  The outcome of this research will guide users of the material on how to protect propeller from getting spoil by microorganism.

1.8                                             LIMITATION OF THE STUDY

There are many or different type of microorganism that can be found in waters but this particular work focuses mainly on the type that attack ship propeller.

1.9                                   RESEARCH QUESTIONS

At the end of this work, student involved shall be able to give answers to the following questions:

1. What are the 4 types of microorganisms?
2. What is microorganism?

• What bacteria are found in ship propeller?

1. What type of bacteria is commonly found in propeller?
2. What are fouling organisms?
3. What is marine fouling?

• What causes biofouling?
• How can biofouling be prevented?

1.10                                  SCOPE OF THE STUDY

The unwanted accumulation of microorganisms, plants, algae, or animals on ships is termed biofouling. Marine biofouling often increases the surface roughness of ship propellers, resulting in speed loss at constant power or power increase at constant speed.

For a better understanding of the impact of  biofouling on the fuel consumption and greenhouse gas emissions of ships, its effect on ship self-propulsion characteristics needs to be studied. Self-propulsion describes a condition in the ship propulsion test.

1.11                                             DEFINITION OF TERMS

i. Microorganism or microbe:  is an organism that is so small that it is microscopic (invisible to the naked eye).

ii. Microbiological contamination:  refers to the non-intended or accidental introduction of microbes such as bacteria, yeast, mould, fungi, virus, prions, protozoa or their toxins and by-products.

iii. Algae: A single-celled or multicellular eukaryotic, photosynthetic organism.

iv. Flagellum: A long thin appendage present on the surface of some cells such as bacteria and protoctista which enables them to move.

1. Propeller: A propeller is a type of fan that transmits power by converting rotational motion  into  thrust, which  is the power unit of a ship

1.12                                           PROJECT ORGANISATION

The work is organized as follows: chapter one discuses the introductory part of the work,   chapter two presents the literature review of the study,  chapter three describes the methods applied,  chapter four discusses the results of the work, chapter five summarizes the research outcomes and the recommendations.