Reliability and accuracy for chemical tanks
Summary
An Ultra 3
non-contacting ultrasonic level measurement instrument was supplied to a major chemical manufacturer, resolving a problem they had in the effective gauging of Sodium hydroxide.
The Pulsar equipment replaced ultrasonic equipment previously supplied by a different manufacturer which had not dealt with the multiple echoes from the dome top of the tank. Cost-effective measurement, providing easily-read local display for the plant operators.
The tanks pictured are 3.6 metres high, with a deep domed top. The ultrasonic equipment that had been previously in place was failing because of the multiple echoes created by the ultrasonic pulse bouncing around the inside of the vessel. Multiple echoes can be a problem, especially when considering relatively short shot applications on liquids. In this type of application, the multiple echoes are almost as significant as the “true” echo and can swamp the transducer. The echo-processing software can have difficulty in discriminating the correct echo from the mass of competing signals. Pulsar non-contacting ultrasonic instruments have the advantage of
DATEM echo processing software, which leads the world in terms of sophistication.
DATEM
is able to pick out the correct echo among all the competing “noise” and, once identified, will maintain it’s contact, following it as the level rises and falls. On rare occasions, even
DATEM
will not pick out the correct echo automatically. In these cases, it is a simple matter to identify the correct level, after which
DATEM
will take over and continue to follow the correct echo against all competing signals. In this application, Pulsar supplied Ultra 3 controllers, mounted locally to the tanks to provide local display for the plant operators. The tanks are cylindrical, and the
Ultra 3
uses the measurement of liquid level to automatically calculate the volume present in the tank. late the volume present in the tank. Both high and low level alarms to warn staff of potential problems and to identify re-order points. The transducers used were flanged
dB6
, with a PTFE face to protect the transducer from the caustic chemicals. The
Ultra 3
and
transducers
are easy to install and simple to set up, and, using Pulsar’s unique menu driven set-up routines, installation was completed in only a couple of hours. The correct level was accurately identified straight away by the equipment, which has provided accurate measurement now for an extended period, proving that Pulsar equipment has the staying power for tough applications.