Filter Basin Rehabilitation

Maintenance work for sand filter

This rehabilitation work solves problems in filtration facilities and serves as a basic for realizing supply of safe drinking water. 　The effect is as follows:

■ Reduction of burden on Environment

No more new filter media and No more industrial waste. It is hard to procure new filter media due to the environmental protection in Japan.

■ Cost Advantage

Achieve cost reduction to do rehabilitation work than media replacement. In case of large amount of filter media is needed , the bigger purification plant, the higher cost advantage.

■ Washing capacity

Propose best media washing solutions and washing machines for different media conditions. Washed sand medial has similar capacity with Manganese.

Process

Step 1	Examination	Examine filter bed and filter media and propose the best rehabilitation work
Step 2	Take media out	Following the construction, take filter media out
Step 3	Cleaning and Repair	Maintenance work in the filter ( wall, underdrain, surface washing pipes etc. )
Step 4	Media washing	Washing and sieving as to the media condition
Step 5	Restore media	Install the washed clean media to the filter bed and examine it at last


Take out media from bed	Repair underdrain	Wash empty filter basin	Install washed media again

Rehabilitation Work for Media Washing

1. Washing and Sieving of media

Sieving filter media to separate Anthracite, Filter sand and gravel for each

2. Decide washing method

Consider the best washing solution and decide proper system based on the examination result

“Siphon Washing system” which can exfoliate attached sludge without particle crushed.

	Washed by conventional method	Contaminated sand	Washed sand by Siphon Washing