Non-invasive liquid level measurements in tank farms
Safe and efficient tank unloading
When unloading petrochemical products, it is crucial to maintain defined flow rates in order to prevent electrostatic charging and the associated safety risks. At the same time, plant processes must not be interrupted by invasive measurement technology. Clamp-on ultrasonic technology enables reliable, ATEX-compliant flow measurement from the outside – without any intervention in the pipework and with continuous process safety.
Measurement tasks and requirements
It is crucial that a tanker is unloaded as quickly as possible whilst remaining within the permissible limits for safe operation. As the unloading rate increases, so does the static electrical charge in the pipeline, thereby increasing the risk of sparking. The task was to ensure a flow velocity of just under 3.5 m/s in order to maintain flow without sparking. The installation of invasive flow measurement technology involves cutting into the pipework and temporary interruptions to the process. In isolated cases, leaks and other difficulties may also arise when restarting raw material transport following the installation of in-line measuring instruments. Due to the low electrical conductivity of the raw materials handled at tank farms, electromagnetic induction measurement methods are not suitable.
Project specifications at a glance
- Industry: Chemicals and petrochemicals
- Installation type: Stationary
Medium: Petrochemicals
Technical solution
Non-invasive clamp-on flow measurement based on ultrasound offers an ideal solution for tank farms. It enables reliable and repeatable non-contact measurement through pipe walls without the need to shut down sections of pipework or entire plant areas. Katronic’s partner in the Benelux countries, U-F-M B.V., uses 13 Katronic KATflow 170 ATEX flowmeters to ensure that a wide range of petrochemicals are unloaded into a so-called ‘hydrocarbon storage facility’ as quickly, efficiently and, above all, as safely as possible.
Methodology and results
The KATflow 170 uses compact, explosion-proof clamp-on sensors to measure flow rates. The ATEX-certified base unit transmits the flow rate to the on-site control system, which then modulates the volume pumped. The measurements are straightforward, reliable at all times and ensure that all health and safety criteria are met.