Humidification systems

Choose an inlet air temperature that is high enough to negate weather effects (outside air humidity or inside room conditions). The air temperature should not be detrimental to the product being granulated. (To achieve consistent process year round, a dehumidification/humidification system is necessary, which provides the process air with constant dew point and, hence, constant drying capacity.)... 

C.I. Direct Brown 95 at this new LAQL. Because of the problems encountered with the midget impinger humidification system, changes were made to incorporate one large impinger and supply the humidified air to the filter cassettes at atmospheric and not reduced pressure. Again, 60 L of humidified air were pulled through each cassette. The results of this study are shown in Table V. Recoveries of C.I. Direct Black 38 and C.I. Direct Brown 95 were approximately 90%. 

Planned inspection of evaporative cooling systems and air humidification systems (annual). 

Planned air washer, or humidification systems cleaning program (six monthly), to include washout, cleaning, disinfection, microbiological testing, and the issuance of a conforming test certificate. 

Humidification systems should be well drained. No condensate should accumulate in air-handling systems. 

For a vehicle application, the humidification system at room temperature should be designed taking into account criteria of constructive simplicity and reliability. 

Apply optimized foam structures to humidification systems to show improvement in humidification potential. 

Apply mathematical model to design optimized humidification systems (i.e., lowest pressure drop, highest humidity, and lowest heater temperature). 

It was shown that carbon foam is beneficial to humidification systems for fuel cells. The foam has demonstrated the ability to utilize waste heat from power electronics to both heat and humidify ambient inlet air to 80°C and 80% relative humidify. 

A wide range of drying conditions typically -20 C to 100°C (with auxiliary heating) and relative humidity 15%-80% (with humidification system) can be generated. 

For automotive operation, it would be helpful to have a membrane material that could function with high proton conductivity at a low RH and higher temperatures. It would allow for simplified humidification systems and improved heat rejection (smaller radiator) and improved cell performance (mass transport) is expected due to the absence of liquid water. Membranes that exhibit sufficient conductivity at high temperature by retaining water necessitate the use of higher stack pressures (and higher parasitic compressor-related losses) especially as the temperature exceeds the boiling point of water at ambient pressure. 

Trends in short- and lOTiger-term directions for key fuel cell components including electrocatalysts/supports, membranes, and bipolar plates have been elaborated in this section improvement of the performance and durability of these components will directly impact the entire automotive fuel cell system requirements, complexity, and cost. Durable catalysts with enhanced ORR activity, durable membranes that perform at very low humidity and durable bipolar plates that have low contact resistance will not only increase the power density and cost of the fuel cell stack but also simplify and lower/eliminate system component costs of the air compressor, humidification systems, recycle pumps, radiator, start-up/shutdown and freeze-start-related components, etc. A combination of advances in all the fuel cell components discussed above, system simplification, governmental policies that are sensitive to sustainable clean energy, and development of a hydrogen infrastructure will enable achieving the projected technical and cost targets needed for automotive fuel cell commercialization. 

Section 3.4. Also, it makes economic sense to operate the fnel cell at maximum possible power density, even if the extra weight, volume, cost, and complexity of the humidification system are taken into acconnt. With larger cells, all these are proportionally less important. 

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