Lithium hydroxide (LiOH) absorbent is used for both active CO2 absorption (powered scrubber systems) and passive CO2 absorption (hanging curtains). Lithium hydroxide outperforms other absorbents at low temperature or elevated pressure such as in disabled submarine, DISSUB. ExtendAir® LiOH curtains provide 55% increase in absorbent weight per given storage volume compared to granular LiOH. What this means to a submarine crew is increased life support duration without sacrificing the limited available space. ExtendAir® curtains outperform granular calcium hydroxide absorbents by as much as 4 times depending on temperature and pressure. The US Navy has approved Micropore’s ExtendAir® curtains for use onboard their submarines (part number RM-0601C, NSN 6810-01-560-3015). The UK Royal Navy approved ExtendAir® curtains for their submarines (OM-0612K, NSN 4240-01-543-3287). Independent testing by multiple Navies (US, UK, Italy, the Netherlands, Singapore, Canada) has confirmed superior performance by Micropore® curtains. Rep Sing Navy AP-10 DISSUB Trials | NSMRL 2003 CURTAIN TEST | ICES-Paper-2007-01-3278 N. Scholes. Several packaging options are available and are described in 110412 ExtendAir® products.
Micropore’s patented technology also improves the performance of fan powered scrubbers while eliminating dust particles associated with granular absorbents (as demonstrated in MIL SPEC shock and vibration testing). Calcium hydroxide based PowerCubes® provide 33% more absorbent than granules in the same storage volume. Calcium hydroxide PowerCube® (part number VM-1050P, NSN 4240-01-626-9829) is designed to work at lower humidity levels experience in modern submarines. Lithium hydroxide PowerCubes® (part number VM-2560P, NSN 4240-01-627-3012) perform at lower temperature and humidity and weigh 40% less than calcium cubes.
In a DISSUB situation, maintaining the quality of your atmosphere with the ExtendAir® curtains is vital to survival. Knowing when to deploy the curtains is just as critical. The Analox Sub MkIIP portable hyperbaric monitor continuously monitors oxygen, carbon dioxide, pressure and temperature in the escape compartment and is the only continuous analyzer compliant with NATO STANAG 1320.
TPG Maritime is a world leader in development, design, construction and life cycle support of submarine atmosphere control systems. TPG is partnered with Micropore to incorporate PowerCube® adsorbents in TPG’s CO2RE scrubbers (https://www.tpgroupglobal.com/what-we-do/defence/maritime/carbon-capture).