Keeping the right level; preventing wastewater spillovers case study
SmartScan 25 provides a most accurate ultrasonic solution for level measurement of waste water flow in a wastewater plants.
Wastewater plants provide the cities water purifying services, to maintain a green environment for the local habitants as well as the natural resources. The amount of wastewater transferred by the local municipalities to the plants is measured daily and therefore demands a highly accurate measurement device.
The city water and wastewater department sought an ultrasonic level measurement solution that will provide an indication of the waste water level running from the city sewage to the purifying plant.
The city operates several wastewater stations scattered in the different locations around town. The wastewater is running into the station through a open channel, during which it is cleaned of trash and sand. There are few problems that might be encountered when operating an ultrasonic level measurement gauge in a wastewater station:
- The open channel is located in a rather small chamber that contains ladders, pumps and other equipment. This equipment may cause acoustic interferences to the ultrasonic wave, consequently causing inaccurate measurement results.
- The water surface is very wavy, causing rapid change in the water level difficult to be tracked.
- Since the waters entering the station contain both industrial and domestic waste, the environment inside the chamber is rather corrosive and therefore may damage the equipment performance.
The municipality installed one SmartScan 25 unit in one of its stations to indicate the water level running through it. The SmartScan sensor was installed approx. 1.5 meters (4.9 ft) above the open channel, and facing the water flow. The SmartScan control unit was installed near the control room enabling constant view of the measurement results on its LCD display.
The SmartScan unit communicates with the PLC via Modbus protocol, thus providing full control over the unit's features and remote observations of the water's measurement results. Being equipped with an intelligent software algorithm for eliminating surrounding acoustic interferences, SmartScan allows valid and accurate readings of the water level. Lastly, the robust material of its sensor makes it simple for the SmartScan to cope with the corrosiveness of the environment inside the chamber.
Being a two-part system enabled the station a fast installation and set-up of the SmartScan on the channel, providing immediate measurement results to be conveyed to the station's control desk. For the station, uprising of the water level without prompt indication means spillage of large amounts of waste and as a result - environmental damage. The SmartScan provides constant indication of the water level by which the station decides when to close the channel or reopen it.
Moreover, as part of its full featured design SmartScan provides connectivity to five SPDT relays for alarm and pump setup as well as an option to view measurement results in different units such as, distance, level or flow. It is also EX approved for installations in hazardous environments which make it ideal for highly gassy environments.