The Leakwise ID-221 sensor detects the presence of and monitors the buildup of thin layers of hydrocarbons on water. Many petroleum and power companies use it for early detection, warning, and control of oil leaks and spills in wet sumps, tanks, and groundwater monitoring wells with a minimum water level of 30 cm (12.0 in). Other applications include hydrocarbon detection and monitoring in oil/water separators, cooling water trenches, storm water runoffs, retention ponds, boiler condensate tanks, and wastewater sewer systems.
A Leakwise system consists of a controller and one or more sensors (also called detectors). The ID-221 sensor has a high frequency transmitter mounted on a float that maintains its position precisely at the liquid/air interface, despite fluctuations in the liquid level. The ID-221 operates with fluctuating liquid levels up to 45 m (150 ft.), and is controlled by the analog PS-220 Controller, which has two field- adjustable alarm points:• Low oil alarm- Detection of a first predefined layer thickness of hydrocarbons• High oil alarm – Detection of a hydrocarbon layer at a second predefined thickness The ID-221 can detect as little as 0.3 mm (0.01 in) oil on water reliably, repeatedly, and without false alarms. It can also monitor on-line changes in oil layer thickness up to 25 mm (1.0 in). The Controller relays are used for local and remote alarms and control. Continuous built-in diagnostics monitor sensor operation. A stilling well is recommended for all ID-221 installations (available as an optional accessory).
Principle of Operation
The Leakwise sensors use a patented, high- frequency Electromagnetic Absorption technique. Each floating sensor houses a high-frequency electromagnetic energy transmitting and receiving antennas which continuously monitor the liquid surface. Since water absorbs more electromagnetic energy than hydrocarbons, changes in the absorption rate of water indicate the presence or buildup of hydrocarbons. The Leakwise sensors can be used to detect and monitor the buildup of separated or emulsified non- soluble hydrocarbons on water and other aqueous solutions. No other oil sheen monitoring system does this.