Filtration - Graded bed catches bugs more efficiently
By very carefully selecting the layers of material in a graded bed filter, it is said to be possible to catch 99.7% of bacteria and other micro-organisms down to 0.2 µm in diameter. A newly constructed filter, which is being piloted for Scottish Water, can process 216,000 litres of water per day, despite being only 18 in (457 mm) across. The filters are also very easy to backwash with a minimum of water.
A matter of manganese
Filtering out the naturally-occurring mineral from potable water in the North East is a new 37.3Mld pressure filtration plant
Wired for water
Technologies available to cut the cost of treating waste water, by improving efficiency and obviating practical problems, are many and various. Dr Tom Shelley explains