At present, the utilization rate of air conditioning in public places, more and more people in a closed environment for a long time, because of the lack of the necessary air flow, indoor air quality is very poor, easy cause fatigue unwell and the spread of disease, therefore, measures must be taken for air exchange, using fresh air ventilation with heat recovery unit make the fresh air and exhaust air heat exchange equipment, can be very good to solve this problem.
Current status of air quality in public places:
1. Poor ventilation;
2. Large flow of people, more pollution sources, poor indoor air quality;
Measures:
The introduction of fresh air, "Public Health indicators and Limits requirements" for fresh air volume put forward clear requirements.
Causing problems:
Introduce a large number of fresh air, direct discharge of indoor air, resulting in a large waste of energy;
How to solve:
The fresh air ventilation equipment with heat recovery device makes heat exchange between fresh air and exhaust air, which not only effectively improves indoor air quality, but also solves a large amount of energy waste.
Schematic diagram of heat recovery fresh air ventilation equipment
New air volume recommended table for comfortable air-conditioned rooms
Medical treatment, biopharmaceutical and high-end electronic intelligence industries have emerged as the country's large-scale industrial strategy, and these industries cannot be separated from the application of purification systems. Because of the particularity of the purification system, the introduction of fresh air and the discharge of some indoor air are realized by power, so the demand for energy is fixed. In the system without new and exhaust energy recovery devices, fresh air will consume a lot of energy, while the energy in exhaust air will be wasted. If the energy in exhaust air can be recovered and the fresh air can be pre-cooled or preheated, the waste of resources can be reduced to the maximum extent. The system mode of strong delivery and strong exhaust is more conducive to the arrangement and utilization of new and exhaust energy recovery.
In the air conditioning system design of major hospitals, treatment centers and animal laboratories, in order to avoid cross pollution, the distance between new fans and exhaust fans is usually relatively far. Our company can provide liquid circulating energy recovery scheme. This energy recovery method can effectively avoid cross-contamination of fresh and exhaust air, effectively recover the cold heat in exhaust air through liquid circulation, and release the recovered energy into fresh air, so as to achieve the purpose of reducing energy consumption of fresh air. This recovery system can drag one or more modes.
In the process purification site, in order to ensure the purification level of the confined space, these areas are relatively independent and closed. In order to maintain the oxygen content of the air in these areas, the supply of fresh air must be increased to a certain proportion. In this case, air-conditioning systems and plate, wheel or heat pipe energy recovery devices can be used.
With the advent of the 5G big data era, network evolution and the rapid development of the data industry, the scale of large data centers(DC) is getting larger and larger, and the power consumption of data centers is also increasing. According to statistics, the national DC electricity consumption in 2018 was 160.889 billion kW/h, surpassing Shanghai's total electricity consumption in 2018, accounting for 2.35% of China's total electricity consumption. Moreover, It is expected to reach 266.792 billion kW/h in 2023, The average annual growth rate will reach 10.64%, which is approximately equal to the power generation capacity of 2.5 Three Gorges.
More importantly, power consumption has become a bottleneck restricting the development of data center services. The following table shows the proportion of energy consumption of each system configuration in the data center. From the analysis of the data in the table, it can be found that in the non-IT energy consumption, about 63% of the loss is caused by the data center cooling system.
In response to the high energy consumption of the data center cooling system, various energy-saving solutions have been tried in the industry. At the result, Indirect Evaporative (IEC) is one of the most promising cooling solutions.
The following figure shows the working principle diagram and product structure diagram of indirect evaporative cooling system.
The indirect evaporative cooling system mainly includes three core components: plate heat exchanger, spray system, and compressor supplementary cooling system. During the cooling process, the air to be treated inside the data center passes through the air heat exchange device. Firstly, the outdoor air is used to cool the closed indoor air. At the same time, the spray system spray water uses the heat of the outdoor air to evaporate in the plate heat exchange device. Absorb heat to reduce the temperature of the air to be processed. As the result, making cool the circulating air inside the DC to the greatest extent. Throughout the process, indoor air is a closed loop system, while outdoor air is an open system. Outdoor air does not allow enter the DC, thus preventing moisture and pollutants in the outdoor air from entering the DC. Since the treated air does not directly contact with water, its moisture content remains unchanged, realizing isohumid cooling of air.
Operating mode
Depending on the outdoor temperature, the Evaporative Cooling Air-conditioning can adopt three operating modes.
Taking a single set of system (selecting BXB2000-2200-12.0 plate heat exchanger) as an example, the selection calculation shows that compared to a pure refrigeration and air-conditioning system, adopting an indirect evaporative cooling system. The air sensible plate heat exchanger can recover 194kw per hour. Spray system can absorb 686kw of heat, and recover a total of 880kw of heat. It can be seen that the use of an indirect evaporative cooling system can save 352kw*h of electricity per hour for the evaporative cooling system, and the energy saving effect is significant.
With the further development of China's economy, the use of green energy will be more and more extensive. Heat pump dehumidification dryers with plate type obvious heat recovery function have developed rapidly in recent years and have been widely used in the Yangtze River basin, southwest China and South China.
The unit using the inverse cano principle at the same time, combined with efficient heat recovery technology, in the whole drying dehumidifying process, through the duct the wet air within the chamber connected to the host using the sensible heat plate heat collector recovery of the sensible heat and latent heat of hot and humid air, thermal recycling, greatly improve the performance of the host, improve the drying speed and material quality. The waste heat can not only improve the performance of the unit, but also reduce the thermal pollution to the environment and alleviate the urban heat island effect.
The heat pump drying heat recovery system is not only used in the mud drying system, but also widely used in many other drying industries. It has the characteristics of good drying quality and high degree of automation, and is the best choice product for energy saving, green and environmental protection in the modern drying industry.
Heat pump dryers with and without heat recovery working principle
When the heat pump dryer dries the air, the air forms a closed cycle between the drying chamber and the equipment. The evaporator's heat absorption function is used to cool and dehumidify the hot and humid air, and the condenser's heat release function is used to heat the dry cold air, so as to achieve the effect of cycle dehumidification and drying.
The main difference between heat recovery function and heat pump dryers without heat recovery function lies in the different air circulation modes. The former is equipped with plate type sensible heat exchanger, which plays the function of pre-cooling and preheating in the air circulation process, reducing the load of compressor operation and achieving the purpose of energy saving.
Heat pump drying system operation mode
Energy saving analysis of heat recovery
Taking a heat pump dryer as an example, the air temperature of drying is designed to be 65℃, the relative humidity is 30%, the circulating air temperature is 65℃, the temperature before passing through the evaporator is 65℃, and the temperature after evaporation cooling is 35℃. The condenser needs to heat the air of 35℃ to 65℃ before it can be used.
After matching with BXB500-400-3.5 heat exchanger, 35℃ return air absorbs heat from exhaust air after passing through plate heat exchanger, and the temperature rises to 46.6℃. The condenser only needs to heat the air from 46.6℃ to 65℃ to meet the use requirements, greatly reducing the load of evaporator and condenser, thus reducing the power of the whole machine, achieving the purpose of energy saving.
Energy saving analysis of heat recovery
Selection and economic calculation
We are very glad to show you the calculation and selection software of plate heat exchanger jointly developed by us and Tsinghua University. If you need, please contact us!
