WATER TREATMENT PLANT

Juan Manuelde Rosas

The companyAySA provides essential water and sanitation services to more than 13.000.000 inhabitants in the City of Buenos Aires and its surrounding area.

In order to provide these services, it operates 3

treatment plants (General San Martín, Ge- neral Belgrano, and Juan Manuel de Rosas), 1

groundwater treatment plant that uses

reverse osmosis (Virrey del Pino), and 16

wastewater treatment plants (Del Bicente-nario, Lanús, Fiorito, Norte, Sudoeste, El Ja- güel, Hurlingham, Barrio Uno, Santa Catalina, Escobar, Garín, Bella Vista, Guernica, Merlo-Fe-rrari, Merlo-Norte, and Florencio Varela).

Juan Manuelde Rosas

WATERTREATMENT PLANT

The Juan Manuel de Rosas water treatment plant is situated in the locality of Dique Luján, district of Tigre, and has a maximum production capacity to supply water to more than

2.000.000 inhabitants.

The treatment plant, extends over an area of

15 hectares, provides drinking water mainly to the northern districts of the Province of Buenos Aires.

Pipeline of3,6 meters in diameter

Sediment

Nozzles/IntakesSandLayer

PUMPINGSTATION

CATCHMENTTOWER

Coagulant

PRECHLORINATION

SIEVES

Polyelectrolyte

Sludge

Flocculators

Flocks

Chlorine Lime

Paraná de las Palmas

RiverThe treatment processThe water treatment process at the Juan Manuel de Rosas Plant is based on a concept of consecutive barriers, and it includes the following steps:

This is the process through which water is collected from the river.

The catchment tower is 80 meters from the shore, is of hexagonal shape, and each of its 3 windows is protected by thick grills in order to keep coarse solids out.

The water that comes into the catchment tower comes in through a 3,6 meters in diameter underground river.

The plant has 4 lifting pumps that work on demand, and have a pumping capacity of 900.000 m3 of water per day, to a height of 15 m above the river level.

This lifting process allows the liquid in the plant to �ow by gravity.

The coagulant dosage is determined based on the tests performed in the plant’s laboratory.

The clay, the microorganisms, and the organic acids present in the river water, have a negative charge. By adding a coagulant that has a positive charge, the negatively charged colloids are destabilized and the clots aggregate (�ocks). The addition of a polyelectrolyte increases cohesiveness, as well as the size and weight of the �ocks.

Once the drinking water goes out of the disinfection chamber, it is ready to be distributed.

Once chlorinated and alkalized, the drinking water for human consumption is sent towards a high-pressure distribution system by means of two water mains, each of 1,2 meters in diameter.

The added coagulant increases water acidity, and therefore lime is added to balance it out.

The amount of lime varies according to the results of the tests performed in the laboratory. This chemical aggregate is essential in order to raise the pH, preserve the metallic distribution networks, and protect the water from the dissolution of those metals.

To disinfect the water, a dose of chlorine in the form of a chlorogenic solution is added to the disinfection chamber in order to deactivate the bacteria that might have got through to this part of the process, and also to achieve a residual concentration that will prevent the contamination of the network, as per the quality standards in effect established by the laboratory.

FLOCCULATIONIt is meant to facilitate the crash of micro-�ocks, initially formed to be able to increase their size. In order to accomplish this, a gentle agitation is necessary, generated by means of a vane agitator installed in the �occulation chambers located at the inlet of the static decanters.

DECANTINGThe water mixed with the coagulant goes into the decanters, �owing slowly, which allows for the precipitation of the �ocks, removing approximately 90% of the clay and 95% of bacteria.

Static Decanters: these are of horizontal �ow. The water �ows through the 80 meters of the decanter, exiting through the laminar modules that lead it to the collector channel towards the �lters. This circuit takes approximately 2 hours.

There are 21 �lters that retain the particles that did not sediment in the decanting stage. Water and air wash: high-tech sand �lters. They operate at a speed of 10m/hour, with a �ltering sand bed of 1 mm in diameter and a height of 1,20 m. They are washed with air and water, counter-�ow.

PUMPING2 COAGULANT DOSAGE3 FLOCCULATION / DECANTING4 DISINFECTION6 DISTRIBUTION8ALKALINIZATION7FILTERING5CATCHMENT AND SIEVE 1

PUMPINGSTATION

4LIFTINGPUMPS

15 kmUNDERGROUND

RIVER

STATIC DECANTERS DISINFECTION CHAMBER

WATER MAINS

Located 80 m

from the shore

It pumps water to a height of15 m

Thick grills to keep coarse solids from going through

Fine grills

Hexagonalshape

SIEVESCHAMBER

CHAMBER

PUMPINGCAPACITY OF900.000 m3

LITERS OF WATERPER DAY

Saturator: the plant also has two lime saturators, which produce up to 300 m3/hour of lime water each, which is added to drinking water in order to achieve a �nal pH adjustment.

A SANITATION ENGINEERING WORK

The Juan Manuel de Rosas Plant is the result of many years of perfecting the processes of water treatment.

Our experts have actively contributed to the design and �ne-tuning of the civic and electromechanical works, the sketch design, and the determination of the diame-ter of the impulsion pipes.

All of this was meant to enhance the analysis processes with a production of 900.000 m3 of drinking water, at maximum capacity.

This plant is the backbone of the north water system, a distribution network capable of feeding a large number of districts in the future.

11/2017

www.aysa.com.ar