Dielectrophoretic Extraction of Water Enhanced by Nanostructure Technology

Dewatering is a widely-used process in many industries, including food fabrication, paper production, and pharmaceutical and biochemical processing. Current thermal dewatering technologies offers better productivity than mechanical- or physical-property-based techniques; however, they consume large quantities of energy and require extensive space and capital investment, because the entire mass of material to be dewatered must be heated to an elevated temperature. In many industrial dewatering processes, large-scale energy savings could be achieved if energy could be applied directly to the water, while avoiding the heating of the remaining materials. This project will investigate such a process ¿ enforced moisture evaporation in a gradient electric field ¿ followed by the removal and condensation of vapor, with the recovery of latent heat that can be returned to the material. In Phase I, a prototype system was fabricated, and an 80 percent increase in the evaporation rate (the loss of weight per unit of time) was demonstrated. Phase II will include: (1) optimization of electrostatically enforced evaporation and latent heat recovery for one of the most energy-consuming applications, paper mills; (2) design of an industrial-scale module prototype; (3) development of fabrication technology for an integrated heat pump (thermoelectric or compression) and heat pipe; and (4) system design of a prototype module for installation in the drying part of a paper machine. Several modules will be fabricated, tested, and then beta-tested on a pilot paper machine. Commercial Applications and Other Benefits as described by the awardee: The technology should lead to energy savings in dewatering processes used for material drying in the production of paper, food, pharmaceuticals, chemicals, coal, and gases. Because of its relatively low operating temperature, the approach would be especially valuable for drying temperature-sensitive products in biotechnology. Also, because the water is extracted in an evaporation process, the proposed technology could have application to the distillation of seawater.