Solutions for Air Humidification and Evaporative Cooling
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Solutions for air humidication and evaporative cooling Control Solutions and Humidification Systems for HVAC/R high efficiency solutions Can protecting the environment be reconciled with our industrialised society? Yes, today this is possible. Indeed, this is the concept of sustainable development: improving the quality of the life, without overloading the supporting ecosystems that it depends on, now made possible by progresses in technology. While until recently sustainable development was simply a desire, a cost and an obligation defined by legislators so as to bequeath a healthy planet to future generations, today it is the only plausible choice. Changing public awareness continues to focus on the more worthy companies, rewarding these with higher sales. A need has thus become an opportunity, a chance not to be missed to unite the need to develop products and services that save energy with the possibility to effectively reduce environmental impact. To encourage sustainable development, many activities are underway as concerns both the environmental policies of individual nations and international organisations (above all the European Union), and specific research and development work. Today, then, solutions to combat global warming and pollution, to live a sustainable existence, to make our cities more liveable and our factories more efficient and virtuous all exist: the technology is here. control energy respect for the consumption environment CAREL has always developed and promoted evolved control systems, proposing innovative solutions in the HVAC/R sector. These are our “high efficiency solutions”, a clear response for environmental protection through optimised and integrated control systems, capable of bringing significant energy savings and consequently reducing environmental impact. These are new solutions for the market, yet the choices made are still in line with our tradition: we have always invested in R&D, right since we first started business, and we continued to do so despite the global recession. These cutting-edge control solutions are now available, and their full potential is ready to be exploited, to achieve an effective competitive advantage on the world scene and be rewarded by the market. Using CAREL “high efficiency solutions” today means doing something concrete to contribute to protecting the environment. It means looking to the future with confidence. Humidify... ...cool while saving Humidification for comfort and industrial processes Air humidity is an important parameter for personal comfort in residential and commercial environments; the right level of air humidity guarantees a sense of well-being and productivity in the workplace. In industrial processes, air humidity control is needed to ensure process stability, product quality and quite often compliance with standards in force. CAREL products respond to the needs of residential, commercial and industrial applications, with special focus on running costs and energy consumption. Other important features of CAREL solutions for air humidification are simple use and installation, and reliability to ensure continuous service. Energy savings: evaporative cooling Air can be effectively cooled by exploiting the evaporation of water atomised into very fine droplets: the change in state, from liquid to vapour, absorbs energy from the air, which is consequently cooled. Evaporation of 100 kg/h of water absorbs 69 kW of heat from the air, for power consumption of less than 1 kW!. In an air handling unit, the supply air can be evaporatively cooled and humidified (direct evaporative cooling, DEC). Alternatively, if the With our innovative outside air humidity is already high, the exhaust air can be cooled by several degrees without solutions, we can guarantee limits in terms of humidity, as it is discharged by the AHU; this cooling capacity, using a heat exchanger, can be used to cool the incoming fresh air with an efficiency that depends on the considerable energy savings heat recovery unit used, yet easily exceeds 50%! (indirect evaporative cooling, IEC). All this means lower unit energy consumption and smaller dimensions and capacity of the cooling for cooling air in AHUs. coil and chiller. To develop these sophisticated solutions, CAREL has fitted a complete and modern air handling unit in its research centre, to optimise performance in all operating conditions and hence offer customers solutions that are together efficient, complete and easy to use. Applications 7 offi ces 9 industry and process 13 datacenters - evaporative humidifi cation and cooling 17 hospitals and operating theatres 21 steam bath 25 Isothermal humidifi cation 29 Immersed electrode humidifi ers 31 Heater humidifi ers 39 Gas-fi red humidifi ers 43 Centralised steam distributors 47 Accessories 51 Adiabatic humidifi cation 53 Pressurised water humidifi ers 55 Compressed air and water atomisers 61 Ultrasound humidifi ers 65 Centrifugal humidifi ers 69 Evaporative cooling 73 Atomisers - evaporative cooling 75 Water treatment systems 83 Water treatment 85 Sensors and protection devices 89 Sensors and protection devices 91 Applications 9 offices The right level of humidity in rooms affects of a humidity generator with controller water from the skin and therefore a lower the level of comfort perceived by people connected to at least one room air temperature is perceived; consequently and reduces the risk of respiratory illnesses. humidity probe. the thermostat is increased by 1-2°C in Humidification is generally required during order to obtain a comfortable temperature. the winter period, as heating systems “dry” The dry air in the winter increases dust the air, causing dry throat, chapped skin present in the air deriving from carpets and and lips and sore eyes. curtains and particles of skin that people lose. This causes problems for people with Comfort depends on the relative humidity: allergies or asthma, which can be reduced in winter, even if there is fog outside (100% by a correct level of humidity in the air. relative humidity), the building heating systems increase the temperature of the If you consider the effect of low humidity air to a comfortable level, around 20 °C. In on objects, there are many examples. Low this way, the relative humidity decreases humidity causes breakage and cracks in to values even as low as 10-30%, which are wooden, paper and textile objects. Objects perceived as dry air. Consequently the skin such as books, paintings on wood, canvas on the hands cracks and the same occurs and paper, valuable wooden furniture can on the lips. As well as being an unpleasant be badly preserved or even damaged by sensation, the nose and throat are “dry”, low relative humidity. Moreover, cracks thus favouring the typical illnesses of the may appear in parquet. winter period. Comfort and production Low humidity affects the temperature The best comfort level is obtained perceived. In summer, perspiration cools thanks to excellent humidity. when humidity is controlled and the skin and makes the temperature Well-being, health and office maintained between values of 40 and perceived lower than it actually is. In 60% relative humidity. For this reason heated environments during the winter objects are protected. the humidification system is made up months, dry air favours the evaporation of humiFog humiSteam compactSteam “Pressurised water “Immersed electrode “Immersed electrode humidifiers” p. 55 humidifiers” p. 31 humidifiers” p. 31 humiSonic “Ultrasound humidifiers” p. 65 offices Maximum comfort with steam Comfort and energy saving with Humidification system control humidification adiabatic humidifiers The control of the humidification systems Steam generator humidifiers use an Adiabatic humidifiers atomise (spray) very and evaporative cooling systems is external energy source, electricity or gas, to fine droplets of water, which are absorbed of fundamental importance. Using take water to boiling point, thus producing naturally by the air. Not producing steam, humidity and temperature probes, the steam. The choice of the type of energy their characteristic principle is very low integrated controller adjusts the capacity depends on availability, cost and the power consumption compared to “steam” of the humidifier to reach the humidity investment necessary. The humidifier can humidifiers. These can also be used in the set-point, without exceeding with use mains water; a solution that minimises summer to cool the air: to give an example, humidification in AHU (humidity limit the cost of the system but which requires using 1 kW of electricity it is possible to probe), in proportion to the flow of air periodical maintenance in order to atomise up to 100 l/h into very small handled (proportional signs), only when remove the mineral salts that accumulate droplets that “absorb” 70 kW of heat from ventilation is running ( flow switch inlet) or, more simply, to replace the cylinders the air. These evaporative cooling systems and with temperature limits /temperature (humidifiers with electrode technology). are increasingly used in air handling units limit probe). The humidifiers must be Alternatively, demineralised water is used in order to cool with very low electrical easy to integrate into air-conditioning (except for electrode technology) so as to energy consumption, with technical unit and AHU control systems, in a way to minimise system shutdown periods and solutions used for dry and wet climates. contribute with the optimisation of system maintenance costs. The steam produced Adiabatic