The client had a problem to monitor a bed level in a Paste Thickener where the suspended solids turbidity changed frequently. The older sonar system failed when high levels of suspended solids were present. There were high levels of scale build-up, due to the water quality used.
We installed a high powered 3 crystal sonar transducer developed for the mining industry that would penetrate the suspended solids in the worst scenario. The high powered array was able to monitor in the “hindered” zone which is just above the “compacted” zone of the bed. The sonar system was supplied with an automated scum cleaner, that operated every 5 minutes. The ORCA sonar transmitter provided two analogue outputs. The first was the “bed level” output and the second was the “clarity” of the water (suspended solids) between the sonar transducer diaphragm and the bed level. The “clarity’ was used as an alarm for the control room to monitor the polymer dosing when the water clarity was low.
Hawk manufacturers the largest range of sonar transducers to provide optimized performance, for all bed level thickener applications.