WATER-TREATMENT PLANT

CALAHORRA

We are going to explain how waste water is

treated to become purified water that can be

safely put back into the river.

WATER - TREATMENT PLANT

Waste water or sewage is collected from agriculture, industry and

domestic use in Calahorra, Autol, Quel and Arnedo and taken to the

Water-Treatment Plant.

COLLECTING OF WATER

In the Plant it is mixed with rain water

that has been collected from the streets of

Calahorra, Autol, Quel and Arnedo

through the storm drain.

Storm tank

PRE-TREATMENT1. SOLIDS ELIMINATION

Water is pumped and forced to pass through 2 different

grilles: the first one, holds back big solids floating on

water; the second, smaller ones.

2. DEGREASING AND DESANDING

Then water is treated to remove sand

and oils. Oil is the pollutant most

difficult to get rid of.

3. COLLECTING OF SOLIDS, SANDS AND OILS

Solids, sands and oils are later

compacted and deposited in a

landfill

TREATMENT

1. PRIMARY DECANTATION

The water passes to a

decantation tank outdoor for

the solid subtances fall at

bottom, and form the primary

sludge.

2. BIOLOGICAL TREATMENT

Now, it is time to remove organic matter.

There are two types of bacteria that can do

this :

- First, anaerobic bacteria digest organic

pollutants without oxygen.

- Later, aerobic bacteria digest the remains

in the presence of oxygen.

3. SECONDARY DECANTATION

The water is separated from

the sludge produced for the

bacterial action, and form the

secondary sludge.

4. SLUDGE TREATMENT

As a result of bacterial

digestion two different

substances are produced:

methane and compost.

SLUDGE

ELECTRICITY

5. GAS LINE

Compost is used in agriculture as a natural

soil fertilizer.

Methane is stored and used to produce

electricity.

Finally the filtered and disinfected

water is poured into the river.

But this

water can't

be drinked.

This project has been realized by:

Claudia Arenzana

Iván Castellanos

Marina Sota

Carla Rangel We hope

you have

like it.