Media Pad Evaporative Air Humidifiers HEF2 Series, for Air Handling Units HEF3 Series, for Air Ducted Systems
Media Pad Evaporative Air Humidifiers Operating features OPERATING PRINCIPLE The operating characteristics of FISAIR series HEF2 and HEF3 are based on the natural effect of water evaporation when air stream passes over a wet surface. Air picks up water vapour which decreases the air temperature since the heat of evaporation comes from the air. This principle ensures that a gas to air mixture occurs without any liquid water being released. Only when carry over occurs, water droplets would be released to the air stream. This is the major difference between the media pad and water spray humidifiers; providing a correct air velocity or mounting integral droplets separator will handle this. ADVANTAGES OF THE HEF2 & HEF3 SERIES Maximum performance with minimum operating cost. Taylor made, using a variety of materials and components. Modular construction for large airflows. Simple to install and easy to service. MEDIA PAD FISAIR humidifiers are available with two different media pad materials: with chemicals to provide stability and wettability. The corrugated and cross channels configuration ensures an expanded surface in contact with the air for water evaporation, together with minimum air resistance. The material is combustible but it represents an economically priced option. media has a compact structure maintaining optimum inorganic, they are incombustible, certified as M0 (Spanish class for fire proof building materials). It s inorganic a small amount of silver ion which acts as a biocide to prevent fungus and also helps any water deposits to release from the media allowing it to stay cleaner. Both types of pad are assembled in sheet steel frames with an integral watering system and handle to enable them to be easily service. CONSTRUCTION Standard Components Optionals / Ancillary Components or more step control. OPERATING DATAS
The evaporative process into the i-x chart The side picture shows a sample of the usual design process for humidification into the Mollier chart: Starting from different methods: 1) Pre-heating+humidification+ post-heating (line A-B-C-D). 2) Heating+humidification (line A-E-D). Rel. humidity Both ways have absolute humidity ( x) different performance in each method evap orati ve humidification while line that, one can define the so called: Temperature SATURATION EFFICIENCY Ratio between the requested and the maximum allowable one, which can be stated as the ratio between the process air dry bulb temperature decrease temperature difference. For the above mentioned examples, the respective efficiencies are: Enthalpy Linea B-C: 28-14 / 28-12,5 = 90% Linea E-D: 36-22 / 36-15,5= 68,3% HUMIDIFIER SELECTION Once the requested humidification saturation efficiency is known, by means of the tables (page 3) and depending of the chosen media pad type, one may obtain the operating cross section is defined, and from that the combination length x height to suit each single installation.
Media Pad Evaporative Air Humidifiers Technical data of media pads (*) Saturation efficiencies & pressure drops of CelPad cellulose media pad Face velocity, 2.0 3.0 4.0 Pad thickness, mm 200 200 200 200 200 200 Saturation 67 63 Pressure drop, Pa 40 60 70 90 230 290 Saturation efficiencies & pressure drops of HU-CELL glass fiber media pad Face velocity, 2.0 3.0 4.0 Pad thickness, mm Saturation 73 90 72 69 67 77 Pressure drop, Pa 20 20 20 30 30 60 (*) Typical design data. For better accuaracy please ask for pad manufacturer operating graphics. REMARK: All aprox. datas. Shadow datas may separator. HEF-3
Specifications SPECIFICATION LEGEND HEF - L - H - T - A - B - C MEDIA PAD TYPE HK: HC: FRAMES MATERIAL G: I: X: Others DROPLET SEPARATOR 1: 0: PAD THICKNESS (mm) NOMINAL HEIGHT (mm) NOMINAL LENGHT (mm) FISAIR EVAPORATIVE AIR HUMIDIFIER HEF2: HEF3: Control of operation 1) Air Handling Units with Pre-Post-heating coils. The performance control can be achieved by a temperature sensor located after the humidifier and a temperature temperature line. 2) Air Handling Units with Pre-heating coil only. hygrostat acting on the pump motor contactor or (in large controller. recommended since the evaporative humidifiers work with only effective in lower figures as well as such washing effect would be lost.
Media Pad Evaporative Air Humidifiers Assembly examples INTO AN AIR HANDLING UNIT The FISAIR evaporative humidifier series HEF 2 is usually incorporated into an A.H.U after the pre-heating coil and before the cooling coil, as shown by the side sketch. As the humidifier is serviced down stream, access provision on that face is enough. INTO AN AIR DUCT SYSTEM The FISAIR HEF3 series humidifiers can be easily integrated anywhere into an air duct system, as shown in the side sketch. Usually the designer must provide a duct section enlargement since air velocities into ducts use to be higher than suitable ones for the humidifier. When it is not possible, there is the option to built a HEF3 unit with pads in V and longer dimension in the direction, having larger cross section/lower face velocity. MODULAR SYSTEM The FISAIR humidifiers can be delivered in modules to build any size of bank into a large A.H.U for big as shown in the attached sketch. SERVICE The Evaporative Fisair Humidifiers require little service as there are few moving parts, but a frequent visual check is recommended. Unless deconcentration is achieved by control of the bleed off and periodic drain down some pad clogging could occur. MAIN TYPICAL APPLICATIONS En general, los humidificadores evaporativos tienen aplicación siempre que se quiera aumentar el contenido de humedad de una corriente de aire conducida, siendo muy comunes los siguientes casos: Comfort air conditioning systems in buildings, hotels, shops, etc. Air Air Air handing units for varnishing and painting booths. handling units for the textile, painting, wood, paper, etc. industries. evaporative coolers for industrial halls summer refrigeration. Pre-coolers for air-condensing units. Pre-coolers for gas turbines. Pre-coolers for diesel cogeneration motors. Indirect evaporative air coolers with heat recovery devices.