Towards new opportunities for reuse, recycling and disposal of used reverse osmosis membranes

Abstract

In an effort to reduce its environmental impact, the desalination industry constantly seeks more sustainable operational and maintenance practices. Based on the increasing number of large desalination plants using membrane technology, the resulting number of old reverse osmosis (RO) modules to be discarded is expected to become a critical challenge. Although the fate of old RO membranes has rarely been considered in the past, a wide range of opportunities can be considered for the potential reuse and recycling of the old modules. Reuse options include direct application of the old membranes within lower throughput systems (i.e. brackish water treatment) and chemical conversion into porous, ultrafiltration-like filters. Other options include, direct recycling of the various module components, and energy recovery through incineration. In addition to the remaining technical issues related to the feasibility of these proposed options, strategic and policy challenges will need to be addressed. However, the concept of product stewardship, already implemented in many parts of the world for electronic wastes and packaging, can provide guidelines for future policies for RO disposal. Finally, the framework for a life cycle assessment of the various disposal options is discussed which may provide guidance for the future implementation of these strategies.