Lead University: Lehigh University
PI: Arup K. SenGupta
Co-PIs: Todd Watkins

Throughout the world, there is a huge stress on supply of appropriate quality potable water. The crisis is also aggravated by the unpredictability of the climate change and adverse impact of global warming. Consequently, the dependence on impaired water sources has greatly increased and there is an urgency to develop appropriate technology to make such such secondary water sources economically viable and environmentally sustainable. In California and Texas, there is a move to treat brackish groundwater and recover secondary wastewater to meet the water demand of the population threatened by frequent droughts in the region. Currently, brackish water desalination is achieved by reverse osmosos (RO) processes that are very energy intensive.We have developed an ion exchange process that is capable of desalianting brackish water with a TDS less than 2000 mg/l with minimum amount of electric energy requirement.

Our ion exchange-based technologies can improve brackish water desalination in two possible ways. First, for existing RO plants, it can avoid the risk of sulfate and silica fouling of RO membranes at high recovery and Lehigh University has been awarded a US patent and another is pending.

SenGupta, A.K. and Sarkar, S. US Patent No. 7901577 awarded in March 8, 2011.”Brackish and Sea Water Desalination by A Hybrid Ion Exchange/Nanofiltration (HIX-NF) Process.”

Secondly, for brackish water with less than 2000 mg/L salinity or TDS, a modified low-energy ion exchange process requires significantly less capital investment and has the potential to be a viable alternative to RO.

Currently, there are about 400 million people around the world who are exposed to toxic level of fluoride due to natural contamination of groundwater. The contaminated groundwater is very often the only source of drinking water for rural population. In the USA, maximum contaminant level (MCL) of fluoride is expected to be lowered soon in accordance with WHO (World Health Organization) guideline and a market for appropriate technology will immediately emerge as it happened when arsenic MCL was reduced by the USEPA in 2002.

Our laboratory-scale research has demonstrated that Lehigh University’s HAIX technology can selectively remove fluoride from contaminated groundwater; Lehigh’s international patent application with USPTO is currently undergoing evaluation.

Two Pennsylvania companies, namely, Purolite Co and Avo Global Inc., enthusiastically support the proposal. Purolite will provide ion exchange resins free of charge for field trial. The proposed project will have the required leverage funding through an existing grant from the US department of state.