Updated: July 2002

1. Configuration and Principle

1) Filtration process
Raw water ascends the filtration bed (3) via the raw water influent pipe (1) and raw water distributor (2). During this process, suspended solids are removed and the filtered water (4) collects at the filtrate through (5) and flows out as treated effluent.
2) Cleaning process
The filter media which have caught suspended solids are sucked from the bottom of the air lift pipe (6) and cleaned while ascending together with air and water. The filter media is separated from the cleaning wastewater at the separation section (7), then further cleaned with the filtered water flowing opposite while it falls down through the special cleaner (8), and is uniformly scattered on the surface of sand layer by the sand distributor (9).

2. Features

- Stable clean filtered water
The continuous upflow sand filter is operated on the continuous cleaning principle, producing stable and good-quality filtered water under constant pressure loss.
- Capabilities to filter high contaminated wastewater
The continuous cleaning process sends suspended solids retained in the filter bed to the cleaning process in a short time. Thus filtration of high contaminated wastewater is enabled.
- Compact facilities
Because no cleaning equipment is required, a less floor space is needed and economic and compact facilities result.
- Easy maintenance control
Because of its simple structure with less supplementary equipment, maintenance is easy and operating costs are low.