同©大学 Tongji University Lesson VI Filtration Tang Yulin 13 April 2017
Tongji University Lesson VI Filtration Tang Yulin 13 April 2017
同瘠大学 Mediaion Tongji University VI、Outline (1)History (2)Slow filtration (3)Rapid filtration (4)Media of filter (5)V-Type filter (6)Pressure Granular bed filter (7)Filtration theory
Tongji University VI、Outline (1) History (2) Slow filtration (3) Rapid filtration (4) Media of filter (5) V-Type filter (6) Pressure Granular bed filter (7) Filtration theory Media filtration
同©大学 Tongji University (1)History of the filtration Filtration is an ancient technology for cleaning water Sand and gravel filters used in India as early as 2000 B.C. Romans dug channels next to lakes to use natural filtration French began filtration around 1750 on small scale Filtration for municipal supply systems began in England and Scotland around 1800 First modern slow sand filtration system in London in 1829 Rapid filtration began in US in 1880s Rapid filtration began in China about 1895 in Shanghai)
Tongji University (1) History of the filtration Filtration is an ancient technology for cleaning water • Sand and gravel filters used in India as early as 2000 B.C. • Romans dug channels next to lakes to use natural filtration • French began filtration around 1750 on small scale • Filtration for municipal supply systems began in England and Scotland around 1800 • First modern slow sand filtration system in London in 1829 • Rapid filtration began in US in 1880s • Rapid filtration began in China about 1895 ( in Shanghai)
同©大学 Tongji University (2)Slow filtration This is the oldest form of filters,with fine sand loaded at low rate,0.05-0.2 m/hour. Slow sand filter treat the raw water by physical straining and biological degradation. There are 3-5 ft sand and form a layer of organic material and micro biofilm in the surface.Every few weeks or months,the top layer will be scrapped. This is a simple operation and no chemicals ones for small systems
Tongji University (2) Slow filtration This is the oldest form of filters, with fine sand loaded at low rate, 0.05-0.2 m/hour. Slow sand filter treat the raw water by physical straining and biological degradation. There are 3-5 ft sand and form a layer of organic material and micro biofilm in the surface. Every few weeks or months, the top layer will be scrapped. This is a simple operation and no chemicals ones for small systems
同©大学 2Sation Influent FILTER Control Valve Overflow -Vent Flow Meter Splash Plate RESERVOIR Overflow Chlorine To Distribution Fig.1 Slow sand filter influent control
Tongji University (2) Slow filtration Fig.1 Slow sand filter influent control