Followings are the important points for any public sanitary project: 1. Financial Aspect 2. Population 3. Quality of Sewage 4. Rainfall 5. Rate of Sewage 6. Sources of Sewage 7. Topography of the Area 8. Present Methods of Disposal 9. Treatment Methods 10. Trends of Town Development. 1. Financial Aspect: Any sanitary project for its complete achievement requires considerable fund. [...]
There are various patterns of collecting systems, but the following are most common: 1. Perpendicular Pattern 2. Intercepter Pattern 3. Radial Pattern 4. Fan Pattern 5. Zone Pattern. 1. Perpendicular Pattern: In this pattern sewers carrying storm water are laid in such a way as to seek the shortest possible path to the natural water courses. The shortest possible path [...]
The sewage systems are classified as follows: 1. Combined System 2. Separate System 3. Partially Separate System. When only one set of sewers is laid, carrying both the sanitary sewage and storm water, it is called combined system. When the domestic and industrial sewage are taken in one set of sewers, whereas storm and surface water are taken in another [...]
The sanitary works can be broadly classified as: 1. Collection Works 2. Treatment Works 3. Disposal Work. 1. Collection Works: The collection works are mainly meant for collecting all the types of waste products of the town. Refuse is collected separately and the sewage is collected separately. The collection works should be such that waste matters can be transported quickly [...]
The sanitation of a town or city is done by two methods, which are: 1. Conservancy System 2. Water-Carriage System. Method # 1. Conservancy System: Sometimes this system is also called dry-system. This system is in practice from very ancient times. Actually this is out of date system even though it is prevailing in small towns, village and undeveloped portions [...]
Learn about the comparison between conservancy and water-carriage systems of sanitation. Comparison # Conservancy System of Sanitation: 1. Conservancy system is very cheap in initial cost. 2. Due to foul smell from the latrines, they are to be constructed away from the living room, so building cannot be constructed as compact units. 3. The aesthetic appearance of the city cannot [...]
Following method is followed for the design of sewers: 1. Zone Formation 2. Sewer Network 3. Sewage Quantity 4. Flow Velocity 5. Sewer Section 6. Grade of Sewers. 1. Zone Formation: The whole town or city in which sewerage system is to be provided is divided into different zones. The layout of sewers is plotted along the roads, and the [...]
Fig. 5.3 shows the common egg-shaped sewer cross-section. The calculation of areas and the wetted perimeters of these sewers at various depths of the sewage involve tedious calculation works. Curves of the hydraulic elements of the standard forms of the egg-shapped sewers are prepared in the same way as for circular sections. The design work can be easily done by [...]
In this article we will discuss about the section and classification of drain. Drain Sections: An ideal drain section should fulfil the following conditions: 1. It should develop self-cleaning velocity with minimum dry weather flow. 2. It should have sufficient free board at its top, even during maximum discharge. 3. It should be easy in construction and maintenance. 4. It [...]
In this article we will discuss about:- 1. Introduction to Screening and Skimming 2. Purpose of Screening 3. Types of Screens 4. Factors to be Considered for Designing Screens 5. Disposal of Screenings 6. Removal of Oil, Grease, Etc. 7. Flotation 8. Skimming Tanks 9. Disposal of Skimming. Introduction to Screening and Skimming: Sewage contains suspended and floating matters in [...]