ABSTRACT
Nowadays, the destruction and pollution of humane environment has produced an ever growing awareness worldwide of the need for more effective sedimentation processes. The main aim of this project was to design and fabricate an experimental sedimentation rig with the objective to determine the rate of settling against time using calcium carbonate as a test sample.The rig consists mainly of the cylindrical tank, valves, motor, stirrer, and the sight glass. For the test run, 82 litres of water and500g of calcium carbonate was introduced into the tank,stirred andwas let tosettle under gravity. The settled height was observed with time at time intervals of 60 seconds,it could be observed that the calcium carbonate settles at different height of 115, 110.5, 104.6, 99.3, 92.5, 85.7, 77.5, 68.3, 60.1, 52.5, 42.3, 33.4, 20.6 and 10.8cm considering the settling behavior. The settling velocity and Reynolds number of flow gotten was 15.42cm/min and 84.5respectively. It could be concluded from the experiment conducted with the rig thatthe higher the concentration is the quicker the sedimentation process is done quickly and the rig could be recommended for waste water industries to study rate of settings of sediments of different particulate distribution from fluids.
TABLE OF CONTENTS
CONTENTS PAGE
Cover page i
Title Page ii
Declaration iii
Certification iv
Dedication v
Acknowledgement vi
Abstract vii
Table of Contents viii
List of Figures
CHAPTER ONE: INTRODUCTION
1.1 Background of Study 1
1.2 Statement of Problem 2
1.3 Aims and Objectives 2
1.4 Significance of Study 2
1.5 Scope and Limitations of Study 3
1.6 Definition of Terms 3
CHAPTER TWO: LITERATURE REVIEW
2.1 Theory of sedimentation 5
2.2 Application Of sedimentation Process 6
2.3 Factors Affecting Sedimentation 6
2.3.1 Particle Size 6
2.3.2 Temperature 7
2.3.3 Currents 7
2.4 Sedimentation Basin Zones 7
2.4.1 Inlet Zone 8
2.4.2 Settling Zones 8
2.4.3 Sludge zone 8
2.4.4 Outlet Zone 8
2.5 Settling Velocity Theory 9
2.5.1 Stokes Law 9
2.5.2 Newton’s Law of Sedimentation/Settling 10
2.6 Context 11
CHAPTER THREE: METHODOLOGY
3.1 Selection of Materials 13
3.2 Basic Design Requirements 13
3.3 Design Details 14
3.4 Sediment Introduction and Outlet System 14
3.5 Materials and Equipment Used 14
3.5.1 Materials Used 14
3.5.2 Equipment Used 19
3.6 Fabrication of Apparatus 24
3.7 Cost Estimation 27
3.8 Project plan 28
CHAPTER FOUR: RESULTS AND DISCUSSION
4.1 Results 29
4.2 Discussion 32
CHAPTER FIVE: CONCLUSION AND RECOMMENDATIONS
5.1 Conclusion 34
5.2 Recommendations 34
REFERENCES 36
LIST OF FIGURES
Figure 2.1: Free Body Diagram of a discrete particle 5
Figure 2.2: Current flow in feed 7
Figure 2.3: Settling Zones 8
Figure 3.1: Mild steel 15
Figure 3.2: Stirrer 16
Figure 3.3: Electric Motor 17
Figure 3.4: Rollers or casters 17
Figure 3.5: Valve 18
Figure 3.6: Tape rule 19
Figure 3.7: Drilling Machine 20
Figure 3.8: Hammer 20
Figure 3.9: Cutting Machine 21
Figure 3.10: File 21
Figure 3.11: Plate rolling machine 22
Figure 3.12: Welding machine 22
Figure 3.13: Spray paint machine 23
Figure 3.14: AutoCAD diagram of apparatus 24
Figure 3.15: Picture of fabricated apparatus 25
Figure 3.16: Labeled diagram of apparatus and P&ID diagram 26
Figure 4.1: Graph of Clear Height against Time 31