Membranes have a service of less than eight years and economical alternative end-of-life options are needed to reduce the number that end up as landfill. Previous investigations have focused on conversion of the membranes to ultrafiltration membranes (another NCEDA-funded project). Membranes elements are complex structures comprising a number of different polymeric components and although direct recycling is not possible, the individual components could be recovered for other uses.
Evaluate the viability of recycling individual components and materials of membrane elements for use in other industries.
Dismantling the membranes is a potentially viable option providing this can be performed at a relatively low cost and the components removed are in a suitable condition for reuse. However, the costs of new materials that the recovered components could potentially replace are comparatively low so this option may not be economically viable. In addition, there are some components that may not be completely recovered or removed intact so there would be some waste generated that would require further treatment or disposal.
Thermomechanical recycling was not found to be a viable option and combustion for energy recovery and pyrolysis for conversion to carbon are possible options but these are considered to be the least favoured. A final option was to reuse the entire membrane element as a decorative bollard and this has broad scope to for many applications where the bollard is currently made from wood, metal or other materials. One key disadvantage that should be noted for any of the recycling options is the intermittent availability of used membranes.
The direct use of the membrane elements to replace wooden bollards is a priority and several leads are currently being explored. The extraction and recovery of polysulfone and/or polysulfone/ABS composite is promising and will also be further investigated.
Total Value: $336,622 (cash and in-kind contributions)
Principal Investigator: Dr Marlene Cran
Title: Alternative disposal methods for end-of-life desalination membrane elements
Length: 21 months
Personnel: 7 collaborators contributing 1.2 FTE
Related Project: Reuse of reverse osmosis membranes
- Related project: Reuse of reverse osmosis membranes
- 2015. Cran, M. Alternative disposal methods for end-of-life desalination membrane elements. Technical Report.