In September 2020 we successfully completed the installation and pressure test of the new tank mounted gas holder on Digester No.2 at Lundwood STW.
Contracted by NMCM, Utile were chosen to replace the 2No. original Kirk Environmental tank mounted double membrane gas holders at this Yorkshire Water site with Sattler 624m3 Model DMGS-TM-16.76M versions. No.1 digester was taken out of service and renovated with the new double membrane gas holder, successfully installed in October 2019. These are both equipped with the Sattler patented inner membrane stabilisation and air distribution systems, sulphur net and central pillar & support belt structure. All features that were not supplied with the units replaced.
The central pillar and support belt structure is the tried and tested design delivered by Sattler for decades, with complete reliability offering 20 year design life. Whilst the high quality membrane materials manufactured by Sattler in-house are the cornerstone to their quality and reliability, this central pillar and support strap system is designed to ensure minimal forces on the tank wall, balcony (if fitted) and anchor ring, thus preventing catastrophic failure in the event of a process fault. These designs are backed up by detailed stress analysis calculations for bespoke tanks at the design stage. Other system designs omitting the central pillar have been proven to impart overly high levels of stress onto the tank wall and anchor ring system and provide no “safety factor” in the event of process fault, which can lead to premature failure of the membranes and anchor ring at the points of highest stress loading.
New lightening protection masts have been installed to BSEN62305, LPS1 rolling sphere method to ensure the complete installation is protected to the highest degree.