The objective of this development was to take advantage of specific properties of microelectrode arrays, such as low flow-dependence, insensitivity to media conductivity and fast re-sponse time   to realize the direct, i.e. membrane-free, electrochemical measurement of dissolved oxygen (DO) in wastewater. The necessity of frequent calibration/cleaning was avoided by the use of a simple disposable membrane-less sensor.
Continuous on-line monitoring of dissolved oxygen in the activated sludge of a sewage treatment plant
Dissolved oxygen is traditionally measured using a Clark cell, which relies upon a gas-permeable membrane for its opera-tion. Such sensors are subject to fouling with subsequent loss of accuracy, making frequent maintenance and calibration necessary.