The concept of heat exchange minimizes the cost of heating and cooling the media. In this case, air flows are considered, the characteristics of which determine the microclimate parameters in private houses, industrial premises, etc. Almost the heat exchange is organized by the recovery system. It acts as a kind of temporary heat accumulator, collecting and giving away its energy. Most often, a rotary recuperator is used, which is appreciated for its high performance, the ability to flexibly configure and other positive qualities.
Recuperator design
Recuperators are practically not used as independent equipment. Most often, they are introduced into the supply and exhaust ventilation units, in which the recovery function is an additional option. The recuperator itself is a metal heat exchanger of a regenerative class. The working basis is a cylindrical rotor, the rotation of which leads to the movement of air masses. The rotor is formed by a package of thin plates that accumulate heat. In turn, the supply and exhaust unit with a rotary recuperator can be included in a larger engineering network. In simple versions, it acts as a means of air ventilation, and at industrial enterprises it also performs the task of utilizing heat from process gas environments. However, the full range of recuperator functions is worth considering separately.
Recuperator functions
The main task is to collect heat for different purposes. Usually - for the subsequent distribution of thermal energy in new incoming air masses, and less often for its extinction. In both cases, a reduction in energy costs for the use of special heat-exchange equipment is achieved. At the same time, the recuperator remains a ventilation unit, which serves to update the air in the room. Depending on the modification, the rotary recuperator can perform air purification and even aromatization. At least getting rid of unpleasant odors is a common property of such devices. More functional models also make it possible to regulate the temperature regime. In this case, the return of stored energy occurs with certain parameters that can be set manually or automatically - again, it depends on the capabilities of a particular model.
Principle of operation
The action of recuperators of this type is based on the transfer of heat from the outgoing air streams (for example, warmed room air) to the cold masses of fresh air. Passing between the rotor plates, the air warms them, and on the other hand, new street flows of cold air come in and are heated by the accumulated heat. The volumes of outgoing and incoming air are determined by the size and power potential with which the rotary recuperator works. The principle of operation of the unit involves the interaction of rotating plates with a drive connected to the mains. Just the presence of an electric drive allows you to finely tune the installation to work with a certain speed mode. On average, the rotation speed is 1 rpm.
Types of device
In the standard version, the working mechanism of the recuperator is divided into several segments - from 4 to 12. Such models are used to remove excess heat generated as a result of technological operations at enterprises. These are condensation rotors that activate their function when the temperature of the air in service drops below the “dew point”. The features of condensing units include the ability of metal elements to withstand moisture. High-temperature devices designed to operate at elevated temperatures are also common. A household rotary heat exchanger is not designed to eliminate excess heat. Such a mechanism is used precisely for its distribution in fresh air flows. However, similar models provide for the possibility of regulation of heating.
Comparison with plate models
Compared to rotary units, plate models do not have a drive and carry out heat transfer in an autonomous mode. The user can manually, by changing the direction of the accumulating plates, change only the throughput of the mechanism. From this we can draw conclusions about the pros and cons of both systems. But first, it’s worth mentioning the general advantages. Both rotary and plate recuperators are small in size and have sufficient performance. This eliminates the need for additional devices, including power ones. If we talk about the differences, then the rotor mechanism is more flexible in adjustments, eliminated the risk of freezing in winter and is energy efficient. But at the same time, it is distinguished by a more complex device and provides a certain proportion of mixing the exhaust flows and fresh air.
Installation work
The recuperator is installed in the prepared channel of the supply and ventilation system. The housing should not come into contact with the wall, as vibrations can be transmitted to it, which will negatively affect the supporting structure as a whole. It is also recommended to use special anti-vibration protection in the form of damping pads for the recuperator. When the support base with legs and profile fasteners is ready, you can proceed with the integration of the housing. Typically, the installation of a rotary recuperator is carried out in a special technical unit, designed in size for a specific model. Fixing is realized with the help of complete connecting fittings - angles, hardware, gaskets and linings are included in the basic set. Further, auxiliary technological circuits can be connected to the rotor. At this point, the connection is made through fittings, adapters, and adapters of appropriate sizes.
Recuperator control
The rotor mechanism is rarely controlled separately from the main supply and ventilation system. In the latest designs, the electronic control of the device through the controller is used. In automatic mode, the owner can set parameters such as speed of rotation, percentage of air intake and exhaust volumes, degree of purification, time intervals, etc. The operation parameters of the mechanism are monitored using sensors, which, in particular, record the equipment throughput . Also, the supply unit with a rotary recuperator can be configured for special operating modes. One of the modern modes of this type is to work under conditions of maintaining a constant air pressure. This program eliminates the risk of overloading the drive with subsequent overheating.
Device Maintenance
The surfaces of the rotor and the housing itself require regular cleaning. The plates are cleaned and, if necessary, additionally treated with anti-corrosion compounds. You should also regularly check the direction of rotation of the rotor, and in the drive system - the quality of the belt tension. Since the recuperator works in close conjunction with other functional ventilation components, it is important to check their condition as well. In particular, the filter, air ducts, dust collectors, valves with sensors, etc. are subject to audit. If possible, the rotary recuperator will not be amiss to remove from the installation site and fully check for leaks. The fact is that in the presence of even minor gaps, the quality of the incoming air deteriorates sharply.
Conclusion
The air recovery mechanism is the easiest way to warm the room. Cold street air is pre-heated with little or no additional energy consumption. Of course, rotary air recuperators, when connected to the network, consume energy for their function, but it is spent on the whole to ensure the circulation of flows. The same example with plate recuperators shows how ineffective an installation without an electric drive can be in operation. Energy supply is also required to power the control infrastructure, which ensures the operation of the entire supply and ventilation complex. Usually these are minimal costs, but as a result they greatly simplify the process of equipment operation.