Flow monitoring

Flow measurement is an important parameter and one that is widely installed to monitor effluent discharge. The information may be used to show compliance with a permit to discharge or to establish trade effluent discharge costs, under the Mogdem formula.

Various techniques are available accommodating open channel and closed pipe applications. Ultrasonic measurement has been widely adopted for open channel measurement relating the level after a flume to the sample's flow. The technique is generally very reliable and is relatively low cost but requires a suitable v-notch weir to be installed, resulting in civil engineering and significant installation costs.

Area-velocity measurement using a combination of ultrasound and level (head of sample) measurement provides a reliable alternative technique for open channel measurement but can also be used within closed pipes. The installation is simple and typically does not incur excessive installation cost.