Dhanbad, September 07, 2026: Researchers at IIT (ISM) Dhanbad have developed a reverse osmosis system aimed at tackling one of the major drawbacks of conventional RO units – the wastage of reject water.
The research team has developed an “Inbuilt Reverse Osmosis Filter with Concentrate Water Management System”, for which the technology has received an Indian patent. The patent number is 593495, while the application number is 202531036943. IIT (ISM) Dhanbad is listed as the patentee.
Unlike conventional RO systems, where the concentrated or reject water is often discharged as waste, the new system is designed to collect this water for subsequent use.
Existing building pipelines can be used
A key feature of the technology is that it can be integrated with the existing water-supply pipeline of a multi-storey building, potentially reducing the need for major changes to the building’s water infrastructure.
The system uses a pump to deliver water to the RO unit under pressure. The water pressure generated within the pipeline due to the height of a multi-storey building can also contribute to the RO filtration process.
During filtration, the RO membrane separates the incoming water into two streams. One produces purified water, while the other generates concentrated or reject water.
The IIT ISM system is designed to route the reject water to a rooftop tank instead of allowing it to flow directly into a drain.
Reject water can be reused
Once collected, the reject water can be used for activities where drinking-quality water is not required, including cleaning, washing clothes and other household purposes.
The technology could therefore help buildings make better use of water that would otherwise be discarded during the RO purification process.
The research team behind the patented technology includes Prof Vivek Bajpai, Dr Pawan Kumar Singh, Dr Madhav Raturi and research scholar Prince Anand.
The researchers said the system could be particularly useful in multi-storey buildings by combining drinking-water purification with a mechanism for managing and reusing RO reject water.
