CHAPTER ONE
INTRODUCTION
1.1 BACKGROUND OF STUDY
A model Sedimentation tank is one of the vital instruments in the field of civil engineering which aids in the separation of flow system. Sedimentation is a physical water treatment process using gravity to remove suspended solids from water; sedimentation is widely used in water treatment plants. In general, the solid materials to be removed have very low settling velocities because of the small particle sizes and density differences together with the effects of hindered settling due to particle concentrations (Leeuwenhoek 1989). These low settling velocities means that the continuous flow tank must have long retention time to allow the particles to settle at the base before clean waters flows out of the system. Basic suspended solid (or SS) is the mass of dry solid retained by a filter of a given porosity related to the volume of water sample, this include particle size not lower than 10µm.
Thus, the extent of particle removal by settling tanks is governed both by the settling properties of the solids and the flow characteristics in the settling zone. Moreover, experiments with the settling efficiency of fine solids may be undertaken, therefore inaccurate flow measurement or failure to take measurement can cause serious or even disastrous result compared with model prediction based on the residence time models constructed with tracer results. (J. C Smith 1993). The differences between ideal and non-ideal flow are thus demonstrated. The equipment has relevance courses in both public health and sanitary engineering as well as to process engineering studies; as such the design, calibration and construction of model sedimentation tank in the department of Civil Engineering of Akwa Ibom State University main campus was undertaken. This project uses basic engineering knowledge to come out with a design of a sedimentation tank for flow measurement to aid the student practically to determine the rate of flow of liquid in a pipe conduit
1.2 FLOW MEASUREMENT
Flow measurement is the determination of the quantity of a fluid, either a liquid, or vapour, that passes through a pipe, duct or open channel. Flow may be expressed as a rate of volumetric flow (such as gallons per minute, cubic meters per minute, cubic feet per minute), mass rate of flow (such as kilograms per hour, pounds per hour), or in terms of a total volume or mass flow (integrated rate of flow for a given period of time). Here, the velocity depends on the pressure differential that is forcing the liquid through the pipe or conduit.
1.3 STATEMENT OF PROBLEM
The large size of most sedimentation tank are made for industrial use and thus has been posing difficulties in movement and due to the limited spacing in the laboratories there is a need to design and construct a reduce-size sedimentation tank in other to reduce cost increase effectiveness and has low energy consumption. However this project will enlighten the student practically, on the theoretical knowledge they have acquired on sedimentation and flow measurement.
1.4 AIM OF THE PROJECT
The aim of this project is for the design; construction and calibration of a model sedimentation tank for flow measurement to aid the student carry out practical on flow measurement.
1.5 OBJECTIVES OF THE PROJECT `
To develop a sedimentation tank for educational and research purposes.
To obtain efficiency data based on different parameters.
To compare theoretical and experimental results.
1.6 SCOPE AND LIMITATIONS
This project deals with the construction of an educational sedimentation tank and conducting experiments on the flow rate efficiencies .The functionality of this design project is limited by
There is no stop watch to use and determine the time taken when conducting practical.
Difficulties encountered when purchasing the materials
1.7 SIGNIFICANCE OF THE STUDY
Sedimentation tank will be designed to help student in the field of interest to know how the process is carried out and also know the principles surrounding the process of sedimentation and flow measurements.
The project is for the studying of the rate of flow in a pipe conduit.
Also serve in the laboratory for practical purpose.
PROJECT OUTLINE
This project is structured in five (5) chapters and sub-themes, each chapter will contained a whole body of the information as regards the design, construction and calibration.
Chapter one highlights the background of the report, statement of problem, significance of study, aim and objectives as well as the scope and limitations of the project.
Chapter two contains literature review and implemented work by different authors, engineers and inventors.
Chapter three highlights the methodology, material selection, design specification as well as the cost estimation.
Chapter four contains the results and discussion
Chapter five draws the conclusion to the entire content and recommendation.