IntraMicron's microfibrous media technology is best utilized for active filtration processes where there is a simultaneous need for particulate and gas-phase contaminant removal. This is accomplished using microfibrous entrapped sorbents (MFESs) and microfibrous entrapped catalysts (MFECs) as filter media, where the microfibrous media filters out the particulates and the entrapped catalyst or sorbent removes the undesirable gas-phase contaminants. Examples of active filtration processes where IntraMicron's technology is readily applicable are described in detail below.
Fuel Cell Cathode Air Filtration
Air contains contaminants such as carbon monoxide, sulfur compounds, volatile organic compounds (VOCs) and particulate matter that are damaging to fuel cell performance. These air contaminants can be removed by adsorptive filtration and particulate trapping with a cathode air filter. The use of cathode air filters causes an increase in system pressure drop and an increase in the required amount of pressure-volume work that the compressor must perform to overcome the pressure drop. Efficient cathode air filtration is an important need for logistic fuel powered solid oxide fuel cell (SOFC) systems with low weight, low volume, low pressure drop (i.e., efficient operation), and high operational life times.
The application of IntraMicron's microfibrous media technology allows the efficiency of the cathode air filtration process to be optimized by using (i) optimally pleated filter designs containing entrapped sorbents as well as (ii) multi-element structured arrays (MESAs) to provide high efficiency cathode air filtration with exceptionally long on-stream process times. MESAs can be constructed of microfibrous entrapped sorbents, enabling the media to behave effectively as a particle filter. The adsorbents entrapped in the microfibrous media are selected to remove gaseous chemical contaminants from the cathode air stream. The compositions of the adsorbents are highly customizable and can be targeted for removal of single or multiple contaminants.
Moreover, the adsorbent particles are much smaller than those used in typical packed beds. Thus, the adsorption efficiency of MESA becomes significantly higher than its packed bed counterparts. Up to five-log removal of molecular poisons and particulates can be achieved in a single pass at high flow rates and low pressure drop. A typical MESA with entrapped adsorbent has a void fraction of 60~90%, which is much higher than a comparable packed bed at the same test gas velocity and thus provides a much lower pressure drop. As a result, the pleated filter structure and the use of microfibrous media allows the maximum adsorbent loading and longer on-stream life without a performance limiting increase in the pressure drop due to parasitic loss of PV power.
Gas Mask Elements, Collective Protection Equipment, & Chemical / Biological Protection
Because of their low pressure drop during operational usage, MFECs and MFESs can be used as gas mask elements or supplementary gas-mask-element filters. The customizable nature of the microfibrous media allows the entrapment of pre-manufactured, customized catalysts and sorbents of different particle sizes and chemical properties. High contacting efficiency ensures that contaminant-laden air is able to be cleaned through physical and/or chemical means without the need for excessive auxiliary power to facilitate air flow. Deployed application sizes for this technology range from personal gas masks designed for combat use to comprehensive whole-building systems dedicated to protecting inhabitants from a variety of chemical and biological threats.
Clean air is vital to building inhabitants and equipment in both residential and commercial structures, and it is estimated that U.S. markets spend over $110 billion in heating, ventilation, and air conditioning (HVAC) costs. Approximately 17% of this amount is expended in the material costs of air filters, the labor required to replace filters, and electricity necessary to push air across the filter bank. These filters are necessary to keep heating and cooling coils clean in order to maintain comfortable air temperatures as well as remove dirt and other contaminants from breathing air. Since no two buildings have the exact same infrastructure, patterns, and behavior, real time monitoring and customized solutions are necessary to optimize the HVAC system. Applying IntraMicron's proprietary optimization methodology with real-time monitoring allows tailored HVAC solutions (including custom filters, maintenance scheduling, and multi-element structure arrays) to be developed that minimize total cost of ownership while providing or improving upon desired air quality levels.