The design of a settling tank depends of the location where it is supposed to work, the degree of wastewater pretreatment (rainwater or technological), flows and the estimated amount of suspended solids in inflowing wastewater (Settling Tanks).
ESL-ZH separators were tested for nominal and maximum flows and the results of the tests were confirmed by the Building Research Institute by issuing the National Technical Assessment ITB-KOT-2017/0212 edition 1. ESL-ZH separators represent class I (according to EN 858-1), it also obtained CE mark allowing to be applied in all EU countries. The chamber is made in accordance with Norm EN 1917 or National Technical Assessment ITB, concrete of class at least C35/45 waterproof ≥W8, with water absorption lower than 5%, frost resistant F150 in the water and F50 in 2% NaCl, stable for petroleum products in accordance with EN 858-1.
Separators have watertight concrete body (chambers of Ø1000–3000 or a separated reservoir chamber) usually does not need extra load. Depending on the separator's location cast iron or cast iron and concrete manholes classes A15, B125, C250 and D400 are used. In order to adjust the location of the separator slab to ground elevation there is an additional top element used made of concrete rings corresponding to the diameter of the separator's body. When the sewer system is located deep in the ground, a reduction-slab and a chimney made of ID 1000 rings can be used. The inlet and outlet are located in the axis of the separator. It is also possible to deviate inlet and outlet axes (consult the catalogue for details) as well as connect several inlets.
A separator placed in a concrete tank with foundation on bearing soils up to 10 m below ground level does not need special foundation and does not need static calculations. Normally, excavation death is prepared using minimum 10 cm C8/10 (B10) concrete substructure or well-compacted layer of gravel or other course non-cohesive soil. Separators should have gravitation inflow. In case of need for wastewater pumping it is recommended that the pumping station is located after the separator. A separator must be located in a place providing access for a suction vehicle.
A separator's body can also be made of PE-HD plastic (consult catalogue pages on separators for details).
In order to reduce maintenance costs and improve ecological safety there is a possibility to connect a separator to alarm systems such as sediment level sensors, oil and overflow sensors. Regular monitoring of the device limits the necessity to physically control the device and shortens the reaction time of maintenance teams in case of a failure.
Oil separators are installed in rainwater drainage systems as one of the devices used in pretreatment of rainwater from watersheds that are likely to be polluted by petroleum derivatives – urban, road and facility:
- roads and motorways
- car parks
- railroad areas
- public transport areas
- transportation equipments depots
- production plants, etc.