The Tarragona petrochemical industry replaced by regenerated water

Two performances related shall make possible the use of 6.8 hm³ annual of regenerated water, of which 5.8 hm³year will be used by companies of the Camp de Tarragona and 1 hm³year for the establishment of environmental flows in the final stretch of the River Gaià. "The industries of Tarragona as regenerated water implies evaluated savings, in a first phase, 6, 8hm³ annual." That is, nearly seven million m³ per year that, for the most part, free drinking water from the network of regional supply which is the consortium of waters of Tarragona. Therefore, it's a water release for domestic uses of the municipalities of the area. This would be the main use. Later, a hectometre of these seven will be earmarked for the restoration of the maintenance of the Gaià River flows. "In total, six are for safe use and one more for environmental use", specifies Jordi Molist, head of the Department of planning of supply of water of the Agència Catalana of l'Aigua.

The substitution of water for reused for industrial applications is the basis of an agreement between the Agència Catalana de Aigua (ACA), l' chemical Business Association of Tarragona (AEQT) and Aguas Industriales de Tarragona (Aitasa), signed on July 30. The agreement stipulates that the Agència Catalana de l'Aigua, owner of the premises of the sewage treatment plant of Vila-Seca, give the exploitation of the plant of tertiary treatment - still under construction - to Aitasa for 25 years. "The Convention has a very simple base - argues Molist - and from there a number of branches that are have been docking." The base is the replacement. Industry renounced these flows of water Consortium, Tarragona, which was committed and, in return, the Administration gives you this plant of regeneration that produces an equivalent flow. From here the operating costs are studied and it is checked the balance is neutral for the industry. In addition, should take into account that there are tax benefits to the use of water regenerated in Catalonia, in the canon of water charged by the Agència Catalana de l'Aigua. "So is balanced balance sheet so that it is correct for the industrial and management".

"The industry renounced these flows of water in exchange for regenerated." "Study costs of exploitation and it checks that the balance is neutral"

The project includes then , the works of construction of a plant of tertiary treatment –that it will be able to arrive to produce, in a principle, 18.911 m³/day– and of the drivings that will make possible the use of water regenerated allocated to several industries of the Camp of Tarragona. In opinion of the boss of the Department of Planning of Water supply of the Agència Catalan of l'Aigua, the project finds in a very advanced “phase”. “Already it has finalised the civil work and, practically, have planted the greater part of the equipment and carries out the phase of urbanisation. In principle, the plant would be finalised during this first semester and, later, would carry out diverse proofs of operation. The intention is that, before finishing the year, already can offer a regular water supply”. As it explains Molist, this performance is to modulate, so that it can expand to measure that increase the demand hídrica of the city councils of Tarragona, beneficiarios of this performance. In a first phase, would obtain 10 hm³ until the year 2015, for afterwards expand the discharge until the 20 hm³, what would involve also civil work.

The plant builds on some terrains situated between the installations of waste treatment water and composting of Vila-Dry and Salou, in the terms of Tarragona and Vila-Dry (Catalonia), and will take advantage of the already treated waters  previously in the debuggers of Tarragona and of Vila-Dry and Salou. This plant of tertiary treatment, funded by the Agència Catalan of l'Aigua, the European cohesion funds –in 85%–  and the Ministry of Environingingment, Rural and Marino, has a budget of adjudication of more than 27,6 million euros. Besides, they will install 17 kilometres of manifolds with his corresponding systems of pumping of water (divided in two stretches) and in the construction of a new deposit, situated in the Pobla of Mafumet (the Tarragonès, Catalonia). The first, supposes an investment of 6 million euros and will allow to drive the water from the plant of regeneration until the deposits situated in the neighbourhood of Bonavista of Tarragona. The second stretch, with a cost of 8,5 million euros, will make possible the supply of the polygon North from the new deposit that builds in the municipal term of the Pobla of Mafumet. “The aim of these drivings is the one to drive the water regenerated to the petrochemical polygons north and south of Tarragona (the first, the most move# away to the plant and in which it builds this final deposit of pipe in the Pobla of Mafumet; and the second, the nearest)”, explains Molist. Like this, as it ensures to Interempresas, covers all the petrochemical industry tarraconense that precise of a supply guaranteeed, to proof of possible droughts, cuttings of supply or possible competition with urban uses, that according to the Law of Waters would be prioritarios. “With this project substitutes a discharge of drinkable water by another of regenerated that, from the industrial point of view is the same, and even better, in a lot of important parameters for the industry. For example, the salinity is very inferior to the one of the water of the Ebro that receive now and the organic matter, practically non-existent, apt for any phase of the industrial process”. The works of construction of the plant together with the drivings have a budget of almost 42 million euros, funded in 85% by the Cohesion funds of the European Union.

Reclaimed water is achieved through the implementation of a number of additional treatments to a conventional sewage treatment plant (often referred to as tertiary treatment) and that create a water quality sufficient and suitable for various uses. I for example, irrigation agriculture and golf courses, industrial applications, recharge of aquifers, among others. In this case, the use of reclaimed water will make it possible to have more water and reduce the consumption of drinking water. "It's finding the water better adapted for each use." "The regenerated not goes to household uses because it is forbidden by the law of water, but the direct reuse of sewage water is optimal for industrial use", explains the head of the Department of planning of supply of water of the Agència Catalana of l'Aigua.

By his part, the previous conseller of Medi Ambient i Habitatge, Francesc Baltasar, the director of the Agència Catalan of l'Aigua, Manuel Hernández, and the director CI Tarragona of Repsol Oil, Joan Pedrerol Galician, signed an agreement that establishes the environingingmental discharges of the low stretch of the river Gaià. “It is a parallel agreement to the reuse, similar and therefore, complementary. And it is the way in that it frees this hectómetro cubic for the compensation of the river Gaià. The agreement establishes which are the ways in that they will free the heights of the reservoir from the which will be compulsory to free this discharge of maintenance. And it establishes the way in that it will realizar the economic balance of this operation that yes could give foot, sometime, to economic disequilibriums. Therefore, this agreement treats these two appearances: the economic balance and the technical way in that it frees this hectómetro cubic”, details Molist, the one who considers to this project of reuse like “pioneer”, regarding the discharge of water to obtain, the requirements of treatment and the number of industries addressees, in comparison with experiences of minor calibrate in Andalucia and Madrid. Likewise, waiting for the results of this operation could carry out other performances in other points of the Autonomous Community. “Whenever it look for this general interest that supposes the renunciation, by part of the industry, of a previously hired source in return of a discharge of water regenerated of big guarantee, from a hydrological vision”, puntualiza. The reuse is one of the axles of the politics of the water of the Catalan government and foresees reach the 190 hm³/year of water regenerated to half term, what would suppose 27% of the annual discharge treaty in the debuggers.