digestion tank
digestive tank

In two-stage systems, different forms of digestate come from different digestion tanks.

Lagoons are kept at ambient temperatures as opposed to the heated digestion tanks.

The reactors produce methane, which can be captured and used as an energy source, usually generating the electricity needed to heat the digestion tanks.

They also allow excess material to be continuously extracted to maintain a reasonably constant volume within the digestion tanks.

The heat produced as a by-product of electricity generation can be reused to heat the digestion tanks.

Floating material is skimmed at this stage using water sprays, and these skimmings are also pumped to the digestion tanks.

The digestion tank contains a filter medium where anaerobic microbial populations - organisms that live in the absence of oxygen - can establish themselves.

The speed of this process is increased by heating the sludge in digestion tanks, enabling bacteria to break down the structure of the sludge.

In this instance, there may be a pasteurisation or sterilisation stage prior to digestion or between the two digestion tanks.

It was then fed into carbon brick digestion tanks where the uranium was dissolved in hydrochloric acid containing a little sodium chlorate.

Alternatively, the addition of ferrous chloride FeCl to the digestion tanks inhibits hydrogen sulfide production.

Here the surplus sludge is initially thickened on gravity belt thickeners and then consolidated in aerobic type digestion tanks having floating type aerators.

Imhoff tanks are being superseded in sewage treatment by plain sedimentation tanks using mechanical methods for continuously collecting the sludge, which is moved to separate digestion tanks.

Construction of a new sludge digestion plant and two secondary sludge digestion tanks was finished in June 1939, and two new settlement tanks were completed in 1940.

Sludge settled from the incoming sewage is treated by retention in enclosed heated anaerobic digestion tanks, a by-product of this process being methane gas which is used for on-site electrical power generation.

More commonly with domestic sewage, the fresh sludge is continuously extracted from the tank mechanically and passed to separate sludge digestion tanks that operate at higher temperatures than the lower story of the Imhoff tank and, as a result, digest much more rapidly and efficiently.

After about 20 days in the digestive tanks, the food waste is composted.

The liquid is then churned into a thick brown soup and pumped into the digestive tanks, which release the methane gas.