We have been using Krohne radar level gauges since 1993: in batch reactors, high-pressure LPG spheres, and in decomposition vessels. For us, it is fair to say that the radar level gauge has proved to be one of the most cost-effective solutions to liquid level measurement. It is certainly our first option for any new level control applications. If you only look at the purchase price, it is true that the initial cost is higher than for a simple pressure level transmitter. But with the pressure transmitter, you have to take account of the on-costs of the instrument stand, extra valving, manifolds, tubing and fittings. The radar level gauge of course is non-contact and, in our experience, generally zero maintenance as well: whilst the pressure transmitter needs continuing calibration and checking of the HP/LP legs for blocking and odd-legging.
Even on the simplest level transmitters, these additional maintenance procedures bring its overall cost up to that of a radar level gauge in about three years. If you add downtime to this equation, the breakeven point is less than one year. With more complicated level measurement problems - such as wet leg or purge systems, chemical seals and displacer systems - the radar system is much less expensive, both in terms of initial purchase price and in running costs. And it has better accuracy and reliability. Our early experience with radar level taught us two things. Firstly, it worked well as a straightforward level detector in situations where other methods had always failed: making polymer in a stirred batch reactor. Secondly, and somewhat unexpectedly, it became a multi-purpose quality control tool as well.
Initially a Krohne BM70 was specified simply as a high/low level detector to ensure the reactor was not over-filled, and that it was empty after draining out. However, by comparing recorder charts we noticed that the repeatability of the level measurement was extremely accurate - to within a few millimetres per batch. Such dependable performance opens up many new uses for the radar level gauge.
* It becomes a temperature control check, since heating cooling causes the reactor contents to rise and fall by predictable amounts.
* To calibrate the batch meters themselves: the three liquid charges could be checked, saving on extra batch meters and only calibrating them on failure.
* It checks on the addition of the catalyst: since subsequent polymerisation causes the reactor contents to fall by a known amount.
* It checks on the addition of other chemicals, which disturb the signal when they are poured in and interrupt the beam.
* Operators can make sure that the stirrer is working, since its action causes surface oscillations, which, in turn, result in a noisy band on the level signal.
All in all it is a bit like having a CCTV inside the reactor. It has gained wide acceptance with the operators, who find it a real comfort factor. Its cost is minute in comparison to the benefits: indeed one batch of material which we saved early on in the programme would have represented a bigger cost outlay than all the Krohne units installed on the site.
A fresh approach to dairy processing VEGA Controls SA
Level Measurement & Control
Ensuring the quality and safety of milk throughout the production process is of the utmost importance in the dairy industry. The VEGABAR pressure transmitters are suitable for hygienic applications. They are an asset in the dairy industry and have been used with success for measuring the milk level and the process pressure in storage tanks.
Read more...Level measurement of an acid dosing tank at a WWTP
Level Measurement & Control
Ferric chloride and other acids are essential chemical substances in water and wastewater treatment. To control the dosing of acid solutions, an Australian wastewater treatment plant uses a special container to store, mix and add these chemicals. The company opted in favour of KROHNE’s OPTIWAVE 1540 radar level transmitter
Read more...Level measurement of leachate from sewage sludge humification
Level Measurement & Control
A municipal utility in eastern Germany operates a state-of-the-art wastewater treatment plant with sustainable sludge treatment. The ultrasonic signal was being partially deflected by the wind, leading to frequent false measurements and inefficient process workflows. The problem was solved by replaced the ultrasonic level sensor with KROHNE’s OPTIWAVE 1540 non-contact radar.
Read more...Groundbreaking measurement system Mecosa
Level Measurement & Control
Berthold Technologies has launched the LoopSeries LB 430, an innovative, industry-leading measurement system designed to enhance operational efficiency with advanced level, density, and level switch capabilities.
Read more...Level measurement of a water sump at a sewage treatment plant
Level Measurement & Control
A major city council in South East Queensland, Australia maintains and operates a wastewater treatment plant (WWTP) for municipal, industrial and agricultural wastewater. Due to the risk of flooding, the water sump must be continuously monitored. The solution is KROHNE’s OPTIWAVE 1540 radar level transmitter.
Read more...Simplicity in measurement Endress+Hauser South Africa
Level Measurement & Control
Endress+Hauser’s new 80 GHz compact radar range is designed to help customers reach their compliance targets through simple yet efficient measurement solutions.
Read more...Case History 196: Unstable condensate level control. Michael Brown Control Engineering
Editor's Choice Level Measurement & Control
The operators in a petrochemical refinery were having great trouble in trying to stabilise the condensate level in a vessel, and this was adversely affecting other loops downstream. Several unsuccessful attempts had been made to retune the controller.
Read more...KROHNE reaches important milestone in Ethernet-APL KROHNE
Fieldbus & Industrial Networking
In December 2023, KROHNE made Ethernet-APL demo devices available to selected customers. This step marks an important milestone in the company’s own Ethernet APL development project for various sensor types. Ethernet-APL technology is a revolution in the process industry.
printer friendly version