Product category:
Plantwide control
News Release from: ABB Automation Tech (Instrumentation + Automation) | Subject: Swirl meters
Edited by the Engineeringtalk Editorial
Team on 09 March 2006
Water facility upgrade cheaper due to
swirl meters
Swirl meters help save thousands of pounds off recent upgrade to the waste water treatment facilities at Biddulph in Staffordshire to meet revised effluent discharge consent from Environment Agency.
Swirl meters from ABB have helped save thousands of pounds off the cost of a recent upgrade to the waste water treatment facilities at Biddulph in Staffordshire United Utilities was required to upgrade its Biddulph works to meet a revised effluent discharge consent from the Environment Agency
This article was originally published on Engineeringtalk on 17 Jul 2008 at 8.00am (UK)
Related stories
Functional safety explained
A new guide explaining all you need to know about functional safety is now available from ABB.
Dual compartments protect temperature transmitters
The TTF350 temperature transmitter is suitable for heavy-duty applications in industries such as oil and gas, power, cement, waste incineration and chemical processing.
The new consent principally tightened the requirement to remove ammonia, but also included tighter limits on BOD and suspended solids.
As part of Amp 3, United Utilities employed Galliford-Costain Joint Venture and Degremont to carry out the upgrade, which required the installation of two aeration lanes.
These improve the supply of oxygen to the bacteria that digest the contaminants.
Further reading
Temperature sensors survive refinery environment
Each thermocouple head incorporates Type N protection of the sensor connections and nonsparking protection for hazardous zones where an explosive gas mixture is not expected, but could occur.
Electronic recorder provides easy data access
The SM1000 electronic recorder has eliminated the need for the company to sift through paper charts and has opened up new possibilities for interrogating and analysing recorded data.
Six flowmeters measuring the supply of air into the aeration lanes form a crucial part of the operation and control system, but the use of conventional thermal mass meters would have meant suspending pipework over the tanks, complete with walkways and handrails to gain access to them.
This is because thermal mass meters require relatively long runs of straight pipe both before and after the meters if they are to give accurate readings.
Instead of requiring inlet and outlet runs of 15 pipe diameters and five pipe diameters respectively, which is typical of thermal mass meters, swirl meters typically need just three and two diameters.
"The extra platforms and pipework would have amounted to between £8000 and £10,000 in my estimation", said Degremont's Project Manager Robert Hill.
"The swirl meters were slightly costlier than thermal mass meters, but they have allowed us to install a tighter configuration of pipework in a smaller area that is accessible from ground level".
"This has enabled an overall cost saving to the installation".
The meters work by first using static blades at the inlet to set the process fluid rotating, or swirling.
The fluid is then accelerated by a reduction in the cross section of the meter before being decelerated and deswirled as it leaves.
A piezoelectric sensor is positioned in the centre of the meter at the point of maximum fluid velocity.
The primary rotation caused by the swirler has a low-pressure zone at its core.
This low-pressure zone is thrown into a secondary rotation proportional to the fluid flow rate so it looks like a helical coil.
At low flow rates, the low-pressure swirls are farther apart and the coil is stretched out.
At higher flows, the swirls are closer together and the coil is compressed.
Areas of slightly higher pressure separate the low-pressure swirls.
The sensor will deflect to the left and right as a pressure swirl passes from one side to other.
The frequency of this deflection is proportional to the volumetric flow rate.
The ABB meters were installed at the Biddulph works several months ago and have been running trouble free ever since.
• ABB Automation Tech (Instrumentation + Automation): contact details and other news
• Email this article to a colleague
• Register for the free Engineeringtalk email newsletter
• Engineeringtalk Home Page
Search the Pro-Talk network of sites
