Since the European Union came into existence, over twenty directives in the field of water have seen the light of day. Two of these, and a third which is currently in preparation, have had a particular impact during the past decade, changing the European landscape in terms of wastewater and drinking water....
Articles dans ce numéro
The water technology market in countries applying for membership of the European Union
In 2003, six new countries are expected to join the European Union. In the meantime, these countries are earnestly engaged in bringing their legislation and water and sewage treatment installations into line with their future partners....
Ozone and UV techniques are used in industry to disinfect and treat water
Ozone, UV? These technologies now have their place in industry. One of their uses is to disinfect industrial process waters. They are also used to reduce the pollutant content of some hard effluents or manufacture ultrapure water....
Tracking down Legionella in all water circuits
In developing countries, 80% of diseases are water-borne. However, the notion of ?zero risk? does not exist even in developed countries. The epidemic of Legionnaires' disease that broke out in Paris in June?July 1998 was a painful reminder of our vulnerability to these pathogens. Solutions to combat these problems nevertheless exist, consisting of a combination of hygiene, maintenance an...
Updating sewage works: a global approach
Large quantities of effluent can sometimes lead to saturation of water treatment plants, which can no longer handle the excess pollution. To remain within water quality standards, the community or factory concerned must increase the treatment capacity of the plant. Several methods exist: optimisation of existing treatment facilities, better aeration or even oxygenation and use of membran...
Water treatment: a case-by-case approach
Chemicals have come to play an essential role in water treatment. Not only do they improve the operation of sewage purification and drinking water treatment plants, but they also equilibrate the water and adapt it to industrial uses. An approach to be carried out on a case-by-case basis according to needs and characteristics of the water....
Assainissement rustique des communes rurales : Quelles sont les chances du lagunage ?
Encore souvent objet de polémique, fermement déconseillé par certains, le lagunage naturel n?a pas dit son dernier mot. Les leçons d'un récent passé commencent à porter. Les maires des petites communes ont tout intérêt à étudier de près cette solution rustique, notamment pour ses performances en épuration biologique et pour ses coûts de fonctionnement réduits. Mais sans parti pris ni pou...
Drinking water: eliminating microorganisms
Drinking water must be free of pathogenic microorganisms. While the presence of indicator germs implies contamination, we now know that their absence is in no way proof of acceptable quality. This conundrum cannot be resolved without paying close attention to each stage of production. This is particularly important given the fact that some microorganisms responsible for water borne infec...
La station d'épuration de Saint Cyprien : une réponse adaptée à des contraintes importantes sur la qualité de l'eau et des boues
L?usine d'épuration de Saint Cyprien (Pyrénées Orientales) a été conçue afin de délivrer une eau traitée de qualité e/NGL1/PT1 pour des variations de charge au cours de l'année allant de 8 000 à 80 000 equivalent-habitants. 4 files en aération prolongée avec déphosphatation biologique permettent d'obtenir en toutes saisons cette qualité. Pendant la période estivale, l'effluent, en partie...
Listening for leaks on drinking water networks
Whatever the stage along the drinking water network, the water must meet very strict sanitary quality criteria and be supplied at a constant pressure and rate. These constraints mean that careful attention must be given to maintaining the hydraulic stability of the network and tracking down leaks....
Les stations d'épuration par filtres plantés de roseaux
Construites depuis 1992, des stations d'épuration par Filtres Plantés de Roseaux (FPR) répondent aux besoins d'une trentaine de collectivités rurales et, à titre expérimental, de quelques fermes qui traitent ainsi les eaux de lavage de leur salle de traite. L'article présente les résultats acquis sur une station conçue pour 200 éq.hab., après 15 mois de fonctionnement, dont les taux de c...
Sewer system diagnostics: going beyond video inspection
A detailed physical inspection of the sewer system makes it possible to go beyond a simple hydraulic study. It is an unavoidable step for anyone wishing to optimise the functioning of his equipment and investment on maintenance....
The water and wastewater on-line monitoring instruments market
The water and wastewater on-line monitoring instruments market has been developing in Europe since the early nineties. The large number of manufacturers, the numerous technological solutions available, in conjuction with a rather unclear legal framework, make it a complex and highly competitive market. The next few years should bring a simpler picture as the market approaches maturity....
L'ozone casse les DCO dures
Cet article fait l'inventaire des propriétés de ce gaz, oxydant puissant, utilisé essentiellement en traitement de l'eau, pour désinfecter, éliminer la pollution d'origine organique. Une réalisation est présentée, ainsi que les installations classiques d'ozonation : pilote et industrielle. Messer et Wedeco se sont associés afin de proposer une solution globale pour l'...
On-line measurement in wastewater treatment: a new direction
Two broad types of measurements can be used to control a wastewater treatment plant: laboratory analysis and on-line measuring. However, the latter method, which is still not widely used in France, is an essential means of improving the functioning of a treatment plant, in other words optimising operational parameters and achieving greater reliability of the treatment process....
Super-Rimiez : la maîtrise d'un réseau d'eau potable en temps réel
Dans cette unité de traitement d'eau potable, la solution de télégestion et de supervision développée par Schneider et Arc Informatique pour Générale des Eaux, permet de gérer l'ensemble des processus assurant l'approvisionnement de l'agglomération niçoise....
Membranes: the solution to a good many problems
Since the early 90s, membranes have occupied an ever-growing place in the water cycle. Depending on where they are positioned, they can be used to clarify, concentrate, purify or separate. Today, the technology is tuned up, and prices are coming down. And the applications are legion?...
Histoire d'eau : L'eau à l'école
Tous les lecteurs de l'E.I.N. ont au moins entendu parler de ?l'École Française de l'Eau', et certains en font partie, de fait. L?école de l'eau évoquée ici n?est pas celle des grands spécialistes, mais celle de jeunes élèves d'un collège de province qui ont le bonheur de vivre près de l'Authie, une jolie rivière picarde. Elle les a inspirés puisqu'ils ont réalisé un ensemble documentair...
