In late 2012, MDD completed the Office of Naval Research’s Broad Agency Announcement in support of the USMC by providing a Remote Water Purification System (RWPS). The program allowed for the development of a technology demonstrator that would aid in filling a gap in USMC water production capabilities. While the USMC has sufficient Reverse Osmosis (RO) water production capabilities for large-scale potable water production, there is a lack of options for mobile, small-scale infantry units. MDD worked to provide the USMC with a water production technology demonstrator at this smaller scale, providing tactical hydration capability to Marines on the move.
In exploring smaller scale methods of water production, MDD experimented with alternatives to Reverse Osmosis, seeking to eliminate RO’s need for high pressure, significant energy, and large piping and equipment, while still being able to produce drinking water for upwards of twenty Marines. MDD focused its research and development efforts to adapting lab-on-a-chip technology with ion concentration polarization to develop a flow cell that would filter heavy metals and salts from water. Ultimately, the ion concentration polarization flow cell was set aside in favor of a more practical, cost-effective method that would more readily scale to higher output requirements. MDD discovered that the water purification necessary to meet the USMC requirements could be achieved through the use of an ion exchange column alone, included in the initial proposal, to remove metals and salts. Therefore, the design effort to develop a working system continued successfully without the flow cell.
The result was a high quality, proof-of-concept demonstrator that used the ion exchange column in combination with aggressive pre-filtration methods that met target goals for potable water quality. The RWPS proof-of-concept is a lightweight, two-man-lift, water purification unit designed to produce potable water for direct hydration of squad-sized units in the field. The water circulation is supplied via an integral hand pump, simplifying the design and reducing unit weight. As the water purification system is not reverse osmosis-based, it has significantly lower power consumption and can use electricity provided by 12VDC to 24VDC supplies, to include HMMWVs, MTVRs, and generator sets with DC power output.
RWPS Technology Demonstrator (Bottom and Top View)