TABLE OF CONTENTS Bringing in suitable bacteria and other organisms to help biochemical reactions. The return of activated sludge is one example. To start a new activated sludge plant, the aeration tank may be seeded with activated sludge from another plant. Digested sludge can be added to undigested sludge to seed it before digestion. Samples in the BOD test also need to be seeded with appropriate bacteria.
Leakage of water into or out of or through a soil or other granular material.
A soakaway.
An absorption pit.
The use of prefabricated segments that are placed in a defective water pipe or sewer to form a new lining. The segments are usually sealed at the joints and grouted.
In a lake, a tide caused by wind raising the water level at the lee end and correspondingly lowering it at the windward end. When the wind drops, the water flows slowly back to the windward end and returns with diminishing amplitude. It helps to mix the water.
The injection of ammonia into boiler flue gas and passing the flue gas through a catalyst bed where the NOx and NH 3 react to form nitrogen and water vapour. Unreacted ammonia passes through with the flue gases but most of it is deposited on the fly ash in the electrostatic precipitators.
A medium which favours the growth of...
