The control of humidity and temperature in the room is of great importance for human health and life. At the same time, the humidification process plays an important role in many industrial areas. For example, the reduction of electrostatic surface charge in the “clean rooms” of instrument-making enterprises, where work is carried out with electronic components and semiconductors, or the suppression of dust by water mist in sawmills and woodworking plants, while at the same time ensuring the required level of wood moisture for subsequent processing. An equally important problem is maintaining the temperature and humidity conditions in warehouses, vegetable stores, greenhouse complexes and the so-called fresh zones of food distribution centers.
Every year the problem of environmental protection becomes more and more urgent, therefore, water, as a natural component, sprayed under high pressure, in the form of a fine mist, turns into one of the most cost-effective ways to achieve a good and natural microclimate compared to traditional refrigerant-based air conditioning systems. . In this regard, water mist technology is rapidly gaining ground in the market as a reliable and extremely energy efficient alternative.
The main component of the high pressure humidification system is the pump. More than 30 years ago, Danfoss pioneered the development of axial piston pumps for water hydraulics. The main advantages of Danfoss high pressure pumps are the absence of lubricants in the design, a minimum number of moving parts and an extended service interval at a minimum level of cost.. Structurally, these pumps are self-lubricating, i.e. do not require the use of lubricants. The water environment itself in the working cavity of the pump provides a sufficient level of surface sliding of the moving parts of the pump, pistons and swash plate. Today, Danfoss is the world leader in oil-free or self-lubricating high pressure pumps that bring all the benefits of axial piston technology to humidification applications.
Compared to plunger pumps found in humidification systems, Danfoss axial piston pumps provide reliable operation and longer life due to fewer moving parts in the pump chamber, as well as an 8000 hour service interval. The volumetric efficiency of some pump models is up to 95% and the energy consumption is extremely low (approximately 4 W per liter of water), which makes the axial piston technology energy efficient when evaluating the return on investment and cost of ownership (TCO) of the entire humidification system at the customer’s site.
Thanks to their unique technology, namely the location of the plungers along the axis of rotation of the pump, axial piston pumps have the lowest noise levels (below 85 dB) and vibrations on the market. The low pulsation frequency during the operating cycle of all 5 or 9 pump plungers simultaneously eliminates the need for shock-absorbing materials and damping devices in the frame structure of the pumping station. Given the relatively small overall dimensions, the axial piston pump is ideal for designing a mobile humidification system, for example, a private house or cottage, a hotel complex or any residential building where the owner can enjoy peace and fresh air with the humidity level necessary for comfortable living.
Danfoss pumps will serve you for a long time, as the parts are made of AISI 304/316 stainless steel, and the friction parts of the pump internal parts are made of semi-crystalline high performance thermoplastic (PEEK). The wide range of performance of Danfoss axial piston pumps will satisfy the need to ensure the temperature and humidity conditions both in a small greenhouse and in the largest greenhouse complex, or in an industrial and logistics center with a large coverage area.
PAHT High Pressure Pumps for Ultrapure Water
The Danfoss PAHT pumps are positive displacement pumps and move a constant volume of water per cycle. The flow rate of the working medium is proportional to the number of revolutions of the pump shaft (rotation speed) and does not depend on the outlet pressure. All products comply with the strict European hygiene standards VDI 6022 and HACCP and are certified according to ISO 9001 and ISO 14001. ATEX certification and API certification are available upon request.
High pressure valves for use in humidification and adiabatic cooling systems
Danfoss manufactures a wide range of AISI 304/316 stainless steel valves which are used as sectional valves for water flow control in humidification systems. The valves are controlled by solenoid coils, but if necessary, have a manual reset function. All valves are dirt resistant, pitting resistant and easy to maintain. Degree of protection IP 67 [NEMA 4X]
Nozzles with anti-drip valve
To obtain a water mist or a cloud, stainless steel nozzles are used with low (3–25 l/h) and high flow rates (25.2–344 l/h) depending on the angle and spray area. The nozzle has a built-in anti-drip valve. When the operating pressure drops to 5 bar, the valve closes, preventing the formation of large drops and their subsequent fall down. For optimal performance, supply line pressure must be quickly relieved at the moment the nozzle closes. This is ensured by the use of Danfoss 3/2‑way high pressure valves, which immediately relieve pressure to the drain.
Implementation examples of humidification and adiabatic cooling systems on Danfoss pumps and valves
To date, Danfoss pumps and valves have been installed in a large number of implemented humidification systems around the world. For example, low operating costs and long service intervals were decisive for the customer’s decision to use 26 PAHT pumps for an adiabatic cooling system at Facebook’s first European data center (DPC) in Lulela, Sweden. On a total area of 28,000 m², the pumping group supplies and distributes 13,000 liters of water per hour. The main requirements of the customer were trouble-free operation with minimum service intervals and the use of an oil-free pump to eliminate the risk of contamination of the dehumidifier area with lubricants according to ISO 22000 standards. Using its advanced technologies in the field of humidification and air purification, Condair used Danfoss axial piston pumps, which made it possible to achieve reduce energy costs by 50% compared to traditional cooling methods. The energy consumption at the facility has been increased to 0.005 kWh per kW of cooling. In addition to providing pollution-free humidity, Condair’s adiabatic cooling system maintains humidity levels at optimal levels to neutralize electrostatic charge and prevent damage to server hardware and worse, data loss. Danfoss pumps operate continuously and reliably in one of the most modern and energy efficient data centers in the world. In Russia, adiabatic cooling systems for data centers are not yet very popular, but experts believe that in the coming years, data center designers will show increasing interest in them. The reason is the Federal Law FZ-261, which sets strict limits for energy consumption and requires a 40% increase in energy efficiency by 2022.
Merlin Technology’s manufactures humidification systems for critical applications such as the pharmaceutical and food industries, automotive plants, and microelectronics assembly plants (“clean rooms”). The humidification system of these plants requires the use of only demineralized water, without the possibility of spreading particles or salts of minerals, bacteria or other organic matter. Therefore, the systems must be completely made of stainless steel. The use of pumps with a mineral oil lubrication system is strictly unacceptable. And for more than 20 years, Danfoss has been using PAHT pumps in its humidification systems. “When we started,” company founder Johan Reisinger recalled, “people were still using steam to humidify. But for large areas, the cost of electricity costs was 700–800 W per liter of water. By using Danfoss PAHT pumps, we have been able to reduce our energy consumption to just 3 W per liter! Maintenance is another important expense item. Especially when humidification systems are installed all over the world and an entire service infrastructure is required. “Danfoss promised us,” said Johan Reisinger, “that PAHT pumps typically run at least 8,000 hours before they need service, but field experience has shown that at least 80% of installed pumps actually last twice as long as advertised. We even have pumps that have run 25,000 hours without maintenance! With Danfoss PAHT pumps, installing our humidifiers returns customers on their investment within the first year of operation.” Thanks to the innovative approach of Merlin Technology’s engineers, Danfoss axial piston pumps as part of humidification systems provide temperature and humidity control in factories of companies such as Mercedes, Audi and VW, Bosch and IKEA, such as Velux, Canon, Hipp and Nestle.
Not only in Europe, but also in Russia, Danfoss pumps have proven themselves since 2011 as reliable and practical components for humidification systems. The project on the basis of a greenhouse facility with an area of 70,000 m² in the Leningrad region was implemented by the Dutch company Van der Ende Pompen. The customer was tasked with generating enough water mist from demineralized water to control temperature and humidity for such an ambitious greenhouse business at the time. Creating a reliable fogging device that can regulate temperature and humidity on seven hectares under glass is not an easy task. The average temperature in the Leningrad region ranges from ‑10°C in winter to +23°C in summer. According to Paul van den Bos, Design Engineer for Van der Ende Pompen, the main criteria for selecting a pump for the system were reliability, ease of maintenance and maintenance costs in order to visit the site as little as possible, located at a distance of 2500 km from the nearest service partner. Van der Ende Pompen used Danfoss high-pressure axial piston pumps to calculate the duty point for pump and motor units. The result was the following solution — a parallel bundle of five pumps of the PAHT 90 series. Each pump is capable of delivering up to 120 liters per minute at a maximum pressure of 129 bar, and they are all connected to a collector that supplies water mist to the entire greenhouse through a common line. The maximum capacity of the entire humidification or misting system is 581 liters per minute. Also at this facility, Danfoss high-pressure valves are used in each section. The construction of the greenhouse complex and the installation of equipment and auxiliary systems was completed in the 3rd quarter of 2013, and the residents of St. Petersburg received the first harvest of tomatoes and cucumbers in the winter of the same year.
In Russia, Danfoss is a partner of OOO ES Engineering (St. Petersburg), a leader in the design and manufacture of humidification and adiabatic cooling systems based on Danfoss high-pressure pumps and valves. The company “ES Engineering” provides a full range of services for the installation, maintenance and monitoring of humidification systems, as well as for the training and education of personnel.
Danfoss LLC, the Russian representative office of Danfoss A/S, and EC Engineering LLC will be happy to assist in the selection of an efficient humidification system and its implementation at any customer site.
We look forward to working with you, Danfoss.