Semestral project 2006/2007
Raul Cabrero
Supplement to presentation
“WWTP in Segovia”
E.D.A.R. Loiola
PURIFYING RESIDUAL WATER STATION OF LOIOLA.
(E.D.A.R.LOIOLA)
CARD TECNICA SUMMARIZES
· Name of Work: Residual Water purifying station of Loiola. Cleaning of San Sebastian-Bahia de Pasajes. Guipúzcoa.
· Promoter: Ministry of Medio.ambiente. Hydraulic Work main directorate and Quality of Waters. Hydrographic confederation of the North.
· Designer: Engineer of Ways, Author of the Project: Luis Castile Camera. ICCP. UTE Edar Loiola
· Direction of the Project: Engineer of Ways, Director of the Project: Felipe Roman Gonçalves. ICCP. Hydrographic confederation of the North.
· Construction company: UTE Edar Loiola. FCC Construcciones S.A., Construccciones Olabarri S.L. y SPA Servicios y Proyectos Ambientales S.A..
· Engineer of Ways, Manager of the UTE: Eloy Sanchez-Cid Garci'a-Tenorio (FCC)
· Engineer of Ways, Work Head: Miguel Angel Barreiro Knoll (FCC)
· Direction of Obra: Engineer of Ways Felipe Roman Gonçalves. CHN
· Budget: 25.521.979,01 euros (4.246.500.000 Ptas)
· Term: 36 months
PURIFYING RESIDUAL WATER STATION OF LOIOLA (E.D.A.R.)
Main Characteristics
The object of residual water purifying Station of Loiola is the application to these waters of the necessary treatment of purification, in each case, so that after this process the indicating parameters of quality of waters adapt to the permissible values indicated by the norm, so that the fulfillment of the objectives of quality in the point of spill of the efluent is guaranteed, that is to say, in the average sailor.
The E.D.A.R. of Loiola was declared of general interest of the State along with the Emissaries submarine and terrestrial. Consequently, its financing and construction are the responsibility of the General Administration of the State, through the Ministry of Medio.ambiente and of the Hydrographic Confederation of the North.
The works of the E.D.A.R. of Loiola aid of project and work published in the B.O.E were bid on by means of. nº 212 of 4 of September of 1998. The awarding was solved in favor of the U.T.E. formed by Construcciones Olavarri, S.A. Servicios y Procesos Ambientales, S.A. Fomento de Construcciones y Contratas, S.A., with an amount of 25.521.979 euros (4.246.500.000 pts.) and an implementation time of 36 months, signing itself the corresponding contract the 26 of September of 2000.
To the day of the date the Station is in construction, having given to beginning works in autumn of 2000. Later, nº 1 of the Project has been approved modified, with an increase on the original amount of of 2.549.184 euros (424.148.529 pts), with which the effective budget at the present time ascends to 28.071.162,68 euros (4.670.648.473 pts).
According to the anticipated thing in the General Scheme of Cleaning, residual water station the purifying, unique for all the scope of the Añarbe, is located in the quarries of Kapuene in the district of Loiola near Donostia-San Sebastián, with a nominal capacity of treatment of 4.5 m³/s (6 m³/s in the future), being the predicted line of water the following one:
Work of arrival: in the head of the installation the started by a triple
well at different heights with a security garbage dump that connects the three cameras to each other. The collectors who will arrive at this triple well are the following ones: collector Santa Catherine-E.D.A.R., Herrera-E.D.A.R collector, and collector of the Urumea.
In case of excess of volume or shutdown of the pumping, the collectors enter load and above drain by the overflows of the cleaning network waters of the E.D.A.R. (mainly by those of the E.B.A.R. Santa Catherine and Herrera).
Roughdressing of thicknesses: previously to the gross water
pumping, the roughdressing of thicknesses by means of 6 automatic grates of cleaning with separation between bars of 60 mm will be made.
Gross water pumping: it will be made from independent wells of
aspiration for each collector, by means of three residual water pumps in dry camera by each well, equipped with variadores of frequency that will allow to impel the residual water until a arqueta-channel of installation head.
Pre-cure: the pre-cure begins with a fine roughdressing by means
of three self-cleaning sieves of 6 mm of step, followed of a sand-taken the grease out of process of by means of 6 longitudinal units with ventilation system equipped with a movable car with surface scrapers and pump of sand extraction. In this stage the separation of floating takes place. The grease is taken out by means of ventilation, tranquilization of the surface liquid, floating fat collection, foam and retiring of the sands that settle at heart of the facilities. All the separated remainders in the work of arrival and the pre-cure will stay in containers for their later evacuation.
Biological treatment of high load: it will be made, after the pre-
cure, in two lines of active muds of high load provided with systems of ventilation by diffusers in the biological reactor and of recirculation and mud purge. The air production will be made by means of turbo boost and a system of mud recirculation is anticipated from the movement to the biological reactors, by means of submersible pumps equipped with variators of frequency.
Camera of flocculation-desaireation: physical-chemistry in two
lines with the purpose of preserving the biological treatment is equipped to the installation of a possible treatment before a possible accidental industrial spill. The predicted reagents are ferric chloride and anonic polielectrolit.
Movement: the waters of exit of the flocculation-desaireation
camera will be conducted to the decantators through channels specially designed to obtain an equal distribution of volume between them. Eight rectangular decantators equipped with continuous systems of superficial floating foam collection and evacuation of such settle to the fat concentrator of the pre-cure. The praised/poured off muds are led back, with the help of the scrapers, to the recirculation device. The praised/poured off water will be sent to an arqueta for its spill in the terrestrial emissary.
On the other hand the line anticipated for the mud treatment is the following one:
Density-growth of muds: in the first place the mud in excess is
sifted and it is put under a density-growth process by gravity in three circular systems closed with cover of PRFV with the purpose of increasing his concentration before sending them to the digestion. The clarify one of the systems returns to head of plant through the network of drained.
Anaerobic treatment: the muds will be sent, once thickened, to the
anaerobic treatment by means of a pumping system. The stabilization of muds will be made by means of anaerobic digestion, that allows the degradation of the organic matter by means of a bacterial fermentation in closed enclosure and air absence, which gives rise to the production of biogas that is stored in two membrane gas holders for production of electrical energy in motors of biogas and for the reuse of the residual heat to increase the temperature of the mud in digestion. The anaerobic digestion will be of high load and it will be made in three equal digestors.
Mud dehydration: The muds of the digestors spill to a deposit plug
and, previously prepared chemically by means of a cationic polielectrolitic, they will be conducted to the process of dehydration by means of a pumping group. The mechanical dehydration will be made by means of three centrifuge decantators: one of reserve with separation stages, final compaction and pressed of solids in its interior, obtaining itself a dryness superior to 25 %.
Thermal drying of muds: after the process of mechanical
dehydration, the muds will be put under a thermal drying with the purpose of reducing their volume and managing to obtain a product of dryness superior to 70 %, of possible use like fuel in certain industrial processes. The mud will be gathered together 200 m³ of unitary capacity for its later evacuation.
Finally, we can mention the line of air for the treatment of scents, that consists of three facilities:
Treatment of scents in the pre-cure: in the pre-cure a system of
desodorization for the treatment of scents will settle, by means of gas washing with sodium sodico hipoclorit and hidroxid, a capacity of 68,000 treatment of m³/h, that will reach to the arrival work, roughdressing of thicknesses, gross water pumping and polishes of fine.
Desodorización in the mud treatment: one anticipates another
station of desodorization for the treatment of the originating air of the density-growth system and mud building in recirculation and excesses, with a capacity of 23,000 treatment of m³/hour.
Desodorization in the zone of mud dehydration: One anticipates
a last installation of similar desodorization to the previous ones for the treatment of the originating air of the zone of dehydrated mud storage, attached gallery to dehydration and deposit plug, with a capacity of 7,500 treatment of m³/h.
Due to the geometric conditioners of the parcel and the presence of the road future Hospitals-Martutene, the E.D.A.R. has been conceived in two separated zones, physically united by a tunnel under the road. One of them counts with sufficient pattern for the internal traffic of heavy vehicles.
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