WASTE WATER SYSTEM FUNCTIONING VISIT TO UDINE SYSTEM December 10th 2010.

WASTE WATER SYSTEM FUNCTIONINGWASTE WATER SYSTEM FUNCTIONINGVISIT TO UDINE SYSTEMVISIT TO UDINE SYSTEM

December 10th 2010December 10th 2010

WASTE WATER’S PLANT ARRIVAL CANALWASTE WATER’S PLANT ARRIVAL CANAL

All waste water coming from our houses, schools, …activities pipes, arrive (inflow) to the depuration plantSo those waters contain all our organic refuse, all locals, clothes and other…. Washing water, car refuse and rubbish coming from the streets…

DEPURATION PROCESS STEPSDEPURATION PROCESS STEPS

Depuration processes can be divided into three groups:

1.MECHANICAL PROCESSES.They permit to remove from waste waters solid not melted materialsThey include: filtering, suspended sand removal, oils removal

- FILTERING STEPArriving water passes through an iron grill that blocks solid refuses.We learned that’s important not to throw used cotton sticks in the wc because they can pass through the grill and return to the environment in the sea

- SAND REMOVAL FROM - SAND REMOVAL FROM WATERWATER

During this step sands deposit

in the bottom because of

gravity. With this purpose

water flows slowly

SAND REMOVAL REFUSESAND REMOVAL REFUSE

Discarded sands are gathered

up in a tank

--OIL S REMOVAL OIL S REMOVAL DISOLEATURADISOLEATURA

Gli oli e i grassi presenti nelle acque reflue, entrano in questa vasca: essendo meno densi dell’acqua galleggiano…

Waste water oils and fats enter in this basin: since they are less dense than water, they float….

…A mechanical rotating arm turns around slowly and a connected shovel drives oils to a rubbish dump

This is a particular of the mechanical shovel driving out oils

2. BIOLOGICAL 2. BIOLOGICAL PROCESSESPROCESSES

The biological treatment

reproduces a natural process:

biological decomposition

processes of organical matter

(our refuse) happen more

quickly than normal

Organic matter in water is

decomposed by

microorganisms; oxigen is

needed (aerobical process).

For this reason oxigen is

continuously introduced in the

so called biological basin.

Aerobic bacteria feed on

organic carbon from melted

substances and transform it in

carbon dioxide that releases in

the atmosphere.

As we can see in the photo

water continuously boils….

Some decompositors

SECONDARY SEDIMENTATIONSECONDARY SEDIMENTATION

From the biological

basin water arrives in

sedimentation basins.

Here, the so called

mud-flocks, produced

during the aerobic

reactions, deposit on

the basin bottom

I FIOCCHI DI FANGO SI DEPOSITANO SUL FONDO I FIOCCHI DI FANGO SI DEPOSITANO SUL FONDO

E l’acqua pulita viene spedita nel fiumeSfiorando lungo delle canalette laterali.

At the end cleaned water outflows to the river passing by a narrow gutter

DEPOSITED MUD IS DEPOSITED MUD IS UTILIZED TO UTILIZED TO PRODUCE GASPRODUCE GAS

The mud Gathered up is

subjected to an aerobic

fermentation, inside big

closed digest plan.

The aim is pasteurize the

mud and then transform in

a gas rich in methan.

Methan is used as fuel to

produce electricity for the

entire deputation plan.

…. Here gas is trasformed into electrical energy

Here remaining

mud is dried….

…….then checked

THIS MUD CAN BE THIS MUD CAN BE

REUTILIZED AS MANUREREUTILIZED AS MANURE

… and saved,

This mud, after chemical

analysis, can be utilized

as manure.

The cicle is now

completed.