| 摘要 |
A vertical tube (25) inside the treatment tank (1) has an open top end located above the sand filter (13a-13c), and a bottom end joined to the tank base (27). The vertical tube surrounds the lower part of the mixing device (3) with outlet holes, creating a water transport gap (26) between the inside of the tube and the mixing device (3). The filter cleaning device (22-24) comprises a part in one end of the tube for connecting the latter to an outlet (31) during back-flushing of the filter. A water purification installation contains a treatment tank under atmospheric pressure, a first pump (7) for a providing a level-regulated supply of impure water to the tank, a tubular mixing device with an upper air intake and a lower outlet opening for the air/impure water mixture, a sand filter inside the tank, a purified water collection device (15) beneath the filter, a hydrophore (17) connected to the collection device, a second pressure-regulated pump (18) for supplying filtered water to the hydrophore via a pipe (16), and a filter cleaning device with components (22, 24) capable of providing a direct link between the hydrophore and collection vessel that bypasses the second pump. Hydrophore pressure causes purified water to be forced into the collection vessel and up through the sand filter. A vertical tube inside the tank has an open top end located above the sand filter, and a bottom end joined to the tank base with a tight seal. The vertical tube surrounds the lower part of the mixing device with outlet holes. The diameter of the vertical tube is greater than that of the mixing device, creating a water transport gap between the inside of the tube and the mixing device. The filter cleaning device comprises a part in one end of the tube for connecting the latter to an outlet during back-flushing of the filter. |
