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
CONTENTSPAGE
Cover pagei
Title Pageii
Declarationiii
Certificationiv
Dedicationv
Acknowledgementvi
Abstractvii
Table of Contentsviii
List of Figures
CHAPTER ONE: INTRODUCTION
1.1Background of Study1
1.2Statement of Problem2
1.3Aims and Objectives2
1.4Significance of Study2
1.5Scope and Limitations of Study3
1.6Definition of Terms3
CHAPTER TWO: LITERATURE REVIEW
2.1Theory of sedimentation5
2.2Application Of sedimentation Process6
2.3Factors Affecting Sedimentation6
2.3.1 Particle Size6
2.3.2Temperature7
2.3.3Currents7
2.4Sedimentation Basin Zones7
2.4.1Inlet Zone8
2.4.2Settling Zones8
2.4.3Sludge zone8
2.4.4Outlet Zone8
2.5Settling Velocity Theory9
2.5.1Stokes Law9
2.5.2Newton’s Law of Sedimentation/Settling10
2.6Context11
CHAPTER THREE: METHODOLOGY
3.1Selection of Materials13
3.2Basic Design Requirements13
3.3Design Details14
3.4Sediment Introduction and Outlet System14
3.5Materials and Equipment Used14
3.5.1Materials Used14
3.5.2Equipment Used19
3.6Fabrication of Apparatus24
3.7Cost Estimation27
3.8Project plan28
CHAPTER FOUR: RESULTS AND DISCUSSION
4.1Results29
4.2Discussion32
CHAPTER FIVE: CONCLUSION AND RECOMMENDATIONS
5.1Conclusion34
5.2Recommendations34
REFERENCES36
LIST OF FIGURES
Figure 2.1: Free Body Diagram of a discrete particle5
Figure 2.2: Current flow in feed7
Figure 2.3: Settling Zones8
Figure 3.1: Mild steel15
Figure 3.2: Stirrer16
Figure 3.3: Electric Motor17
Figure 3.4: Rollers or casters17
Figure 3.5: Valve18
Figure 3.6: Tape rule19
Figure 3.7: Drilling Machine20
Figure 3.8: Hammer20
Figure 3.9: Cutting Machine21
Figure 3.10: File21
Figure 3.11: Plate rolling machine22
Figure 3.12: Welding machine22
Figure 3.13: Spray paint machine23
Figure 3.14: AutoCAD diagram of apparatus24
Figure 3.15: Picture of fabricated apparatus25
Figure 3.16: Labeled diagram of apparatus and P&ID diagram26
Figure 4.1: Graph of Clear Height against Time31