Status and Trends of Membrane Technology for Wastewater Treatment: A Patent Analysis

Abstract

Global access to clean water and sanitation has been broadly discussed in the context of the Sustainable Development Goals adopted by the United Nations. In this context, membrane technology has been increasingly applied with great success in wastewater treatment. Considering the relevance of patent information for understanding the current status and future trends of technologies, the patent filings on membrane technology for wastewater treatment in the period from 2011 to 2019 were analyzed. This study comprised a global analysis, aimed at determining the most general aspects, and a qualitative analysis, which consisted of a careful reading of the documents to assess technological statuses and trends. From a total of 7303 patent documents found on the topic, 488 documents were selected for the qualitative analysis. China, Japan and the United States play a leading role in the development of these technologies. Companies constitute the vast majority of the applicants. The focus of the inventions turned out to be: equipment, membranes, customized equipment/processes for specific wastewaters, fouling control and cleaning, combinations of technologies and sustainability. Finally, enhancements in the operational performance of the membrane separation equipment and the development of membrane materials with increased water flow and fouling resistance are found to be key factors to broaden the application of membrane separation technology in wastewater treatment.