{"id":48359,"date":"2026-02-11T15:16:04","date_gmt":"2026-02-11T14:16:04","guid":{"rendered":"https:\/\/tubi.net\/?p=48359"},"modified":"2026-02-11T16:16:11","modified_gmt":"2026-02-11T15:16:11","slug":"first-rain-water-treatment-systems-2","status":"publish","type":"post","link":"https:\/\/tubi.net\/en\/first-rain-water-treatment-systems-2","title":{"rendered":"FIRST RAIN WATER TREATMENT SYSTEMS"},"content":{"rendered":"
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FIRST RAIN WATER TREATMENT SYSTEMS<\/h1>\n
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Rainwater runoff or first flush water is precipitation that falls on impermeable surfaces (asphalt, roofs, paving). This water is particularly polluted because it washes away and transports substances that have accumulated on these surfaces (oils, heavy metals, hydrocarbons) during dry periods.<\/header>\n<\/header>\n<\/div>\n<\/div>\n<\/div>\n
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RULES AND REGULATIONS<\/strong><\/h3>\n

In many countries, environmental awareness and related laws require the adoption of first flush water treatment systems in specific situations. These systems separate light liquids (e.g., oils and hydrocarbons in general) from rainwater runoff from impermeable surfaces before it is released into the environment.<\/p>\n

Their regulation is governed by relevant regional laws or regulations.<\/p>\n

The European technical standard of reference relating to the principles of design, performance and product testing, marking and quality control for the construction of such systems is UNI EN 858-1:2005 \u201cSeparation systems for light liquids (e.g. gasoline and oil)<\/em>\u201d.<\/p>\n

UNI EN 858-1:2005 is a harmonized European Union standard, therefore it allows the marking of products as regulated by Regulation (EU) 2024\/3110 of the European Parliament and of the Council.<\/p>\n

The UNI EN 858-1:2005 standard provides for two classes of separators:<\/p>\n

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  1. Class I<\/strong>\u00a0separators: maximum residual oil content 5 mg\/l (coalescing separators)<\/li>\n
  2. Class II<\/strong>\u00a0separators: maximum residual oil content 100 mg\/l (gravity separators)<\/li>\n<\/ol>\n

    The UNI EN 858-2 standard provides guidance on the criteria for choosing the type and nominal size of separation systems and, for application to fuel stations, car parks, and roads, recommends the choice of Class I separators in the case of delivery of treated water to surface waters, in accordance with the discharge limits indicated by national legislation: Legislative Decree 152\/2006.<\/p>\n<\/div>

    \u201cCLASS I\u201d TREATMENT SYSTEMS SGK\u00a0EcoTanks<\/em><\/strong><\/p>\n

    SGK\u00a0EcoTanks<\/em>\u00a0<\/strong>first flush water treatment systems are certified in\u00a0Class I<\/em>\u00a0by an independent third party for compliance with the UNI EN 858-1 : 2005 standard.<\/p>\n

    These systems consist of large spiral polyethylene pipes (diameters from DN 800 to 2500 mm), suitably sized in terms of volume and equipped internally to perform the separation of light liquids: by gravity (buoyancy) and thanks to the aggregation effect of oily particles by coalescence. Externally, the system is equipped with the necessary access points for inspection and maintenance throughout its operational life, as well as bypass systems to manage any excess flows.<\/p>\n<\/div>

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    1. bypass well<\/strong>\u00a0regulates the inflow to the system and access to the bypass<\/li>\n
    2. bypass<\/strong>\u00a0pipe for transporting water that does not undergo treatment<\/li>\n
    3. inlet pipe<\/strong>\u00a0sized to regulate the inflow of water into the system<\/li>\n
    4. deflector<\/strong>\u00a0that calms the turbulence of the incoming water, confines floating solids, and directs the flow downward, promoting the sedimentation of heavy solids (inert)<\/li>\n
    5. inlet well<\/strong>\u00a0necessary to extract floating solids and sedimented inert materials<\/li>\n
    6. calming tank<\/strong>\u00a0in which light liquids are separated by flotation<\/li>\n
    7. deflector<\/strong>\u00a0delimits the calming volume in the upper part of the tank, acts as a support for the possible installation of an automatic valve for the extraction of light liquids and for the fixing of lamellar packs<\/li>\n
    8. float valve<\/strong>\u00a0(optional) for gravity extraction of light liquids<\/li>\n
    9. PVC\u00a0lamellar packs<\/strong>\u00a0(optional) to increase the filtration capacity of light liquids<\/li>\n
    10. inspection well<\/strong>\u00a0for the extraction of light liquids and bottom sediments, float valve control, and cleaning of lamellar packs<\/li>\n
    11. deflector<\/strong>\u00a0delimits the settling volume in the lower part of the tank and acts as a fixing wall for the lamellar packs<\/li>\n
    12. Coalescence filter<\/strong>\u00a0performs an additional separation of light liquids, can be equipped with an automatic gravity shut-off valve<\/li>\n
    13. Well<\/strong>\u00a0for inspection and maintenance of the coalescence filter<\/li>\n
    14. Outlet pipe for water from the system, positioned slightly lower than the inlet to allow adjustment of the treated flow rate<\/li>\n<\/ol>\n<\/div>

      ADVANTAGES<\/strong><\/h3>\n

      SGK\u00a0EcoTanks<\/em><\/strong>\u00a0first flush water treatment systems offer significant advantages:<\/p>\n