The U.S. Army Corps of Engineers has invented a novel water purification technology that is available to qualified businesses who would use it in new products or services.
Water purification systems struggle to detect contaminants at high dilution, require substantial energy to operate, and can become fouled too easily. The separation and removal of particles including viruses, bacteria, protozoa, spores, clay, hair, proteins, nucleic acids, peptides, lipids, and humic acids represent an ongoing battle.
The contaminants mentioned above all carry a positive charge and Army scientists have used this commonality to develop a system for separating them out in an energy efficient manner. The system and method resist biofouling by design and is shown in the figure at right. The apparatus is comprised of an electrically charged barrier through which water flows. Positively charged particles are diverted out of the flow and water without ions passes through.
If any neutral (uncharged) organic compounds are present in the liquid to be processed, adding charged sorbents including clay, carbon, or zeolite particles to the incoming liquid stream allows the apparatus to process any neutral organic compounds. The charged sorbents adsorb or bind to neutral organic compounds and then the apparatus can repel the charged sorbent (which is a charged species) while it is attached to the neutral organic compound.
The device is energy efficient with power consumption values of less than 5 Watt-hours per Liter (Wh/L) with maximum water production rates of ˜50-mL/min. Parallel units can reach water production rates in excess of 1 gallon per minute and a scaled-up microfluidic system can reach water outputs of about 1 gallon per minute in water desalination or purification.
A membrane isolates one electrode and has an electrically charged surface (positively or negatively charged) preventing the passage of charged species with a charge sign (polarity) that is the same as the charge on the surface of the membrane.
This design prevents electrically charged species (including bacteria) from physically contacting membrane. This contactless filtration function prevents bacterial biofilm formation on the membrane and clogging or fouling of the membrane, substantially reducing the need for replacing or cleaning, and minimizing overall maintenance requirements.
The invention is protected by a pending patent and a patent license is needed to take advantage of this business opportunity.
- The apparatus can be used as a concentrator and separation tool at the same time
- Sensors (conductivity, fluorescence, absorbance) measure the ion concentration of input liquid stream 14 and of ion-depleted stream in order to calculate the rejection ratio of apparatus (1−ion-depleted/input)
- Businesses can productize the invention by licensing US patent application 20180319681 from the Army
- License fees paid to the Army are negotiated during licensing
- TechLink experts navigate businesses through licensing at no charge
- Businesses who license the invention then have the potential to collaborate with the Army's inventors