In the 1970’s the German rivers Rhine and Neckar were considered the „Sewers of the Nation“. Both rivers were classified as Water Quality Class IV (excessively contaminated). Today these rivers, like most others in Germany, are almost of drinking water quality (Water Quality Class II). Within the EU the prodedure for reaching a good ecological state is definied in the Water Frame Guideline – what appeared to be impossible just a few years ago has become reality today: On the river Elbe, public swimming days are being organised – salmon are back in the river Rhine. Even though the level of contamination of most brooks, rivers and lakes has fallen during the last few decades, a great number are still endangered by contaminating substances such as oils. Using the AFRISO-EURO-INDEX Oil-on-water detector ÖAWD, such contamination of still or slow flowing waters can be controlled simply and reliably.
The Oil-on-water detector ÖAWD from AFRISO-EURO-INDEX checks the surfaces of any still or slow-flowing water for contamination through oil. The ÖAWD detector consists of a faultlessly working, self-checking controller with periodic self-test and a floating sensing probe SWS, which is connected to the controller via a 2-core signal cable (up to 50 m length). The floating probe is designed such that the electrodes are kept immersed in water to ensure a closed probe circuit. If a layer of oil appears and floats on top of the water surface, the closed probe circuit is interrupted and changes to open circuit and the controller detects this and signals an alarm condition. The level of immersion of the 2-rod electrode is height-adjustable on the floating probe SWS; oil layer thicknesses of 2-10 mm are detected.
A 230V AC supply is required for the control unit OAWD which is suitable for wall mounting in dry rooms. The control unit incorporates all indication and operating elements (test button for function test, push-to lock button to prevent unintended muting of alarm) as well as all electronic components. A voltage-free relay contact provides for connection of additional alarm units, event reporting systems or for the control of pumps or solenoid valves.
The control unit is available in the version ÖAWD-1 with a built-in response delay of 1 second for still waters or type ÖAWD-8 with a built-in delay of 8 seconds for slow-flowing waters.
The detectors ÖAWD-1 and ÖAWD-8 are for instance used to control open waters or inspection chambers, collection shafts, retention pits or overflow basins.
ÖAWD controls oil contamination of still or slow flowing waters.
