Discussion
Due to the increase in energy prices, from the end of the last century, heat pumps (IN) began to
be used, the principle of their operation is based on the conversion of heat from low-temperature
sources to high temperature, and due to phase changes of the working substances, the heat consumer
ozone R22, R134, R142 freons, as well as carbon dioxide (CO – R744), are used as refrigerants [3,4].
Figure 2 shows the scheme of comprehensive reuse of secondary energy in mines and mines
using heat pumps. The evaporator of the heat pump consists of two circuits. Mine water with a
INNOVATSION TEXNOLOGIYALAR Maxsus son, 2023-yil, dekabr
ISSN 2181-4732
26
temperature of t=6-9 °C is included in the 1-evaporator, and water heated in the KKU cooling system
with a temperature of t=15-25 °C is included in the 2-evaporator. Due to the heating of this coolant,
which is a low-temperature source, the refrigerant boils in the evaporator, that is, its temperature rises
and the evaporation process occurs, after which the refrigerant vapor enters the compressor, where it
is compressed. is compressed with, as a result of compression, the temperature increases further.
Compressed vapors are condensed in a condenser at high temperature and pressure. Heat is supplied
to the water of the heating or heat water supply system (t=65 °C), the refrigerant is cooled, and then
its pressure is reduced through the throttle valve, which again enters the evaporator[8,10].
2 – picture. Principle scheme of comprehensive reuse of secondary energy resources in
mines using heat pumps:
1. Mine compressor equipment, 2. Hot water cooling tower, 3. Mine water injection, 4.
Evaporator, 5. Compressor, 6. Electric motor, 7. Freon, 8. Condenser, 9. Intermediate heater of heat
carrier t= 650 C, 10-boiler room, 11-return of the heat carrier t=500 C, 12-seasonal changer of currents
(instead of cooling tower allows to cool the circulating water of the enterprise in summer), 13-external
consumer, 14-air heaters , 15-return from external consumer, 16-min hot air delivery, 17-min water
discharge device.
The efficiency of the heat pump (IN) is evaluated by the coefficient of conversion (O'KB) [2],
which shows the ratio of the amount of heat energy produced by the IN to the consumed 1 kW of
electrical energy (Fig. 3).
3 – picture. Dependence of heat pump efficiency on low potential source temperature φ=f(T)
INNOVATSION TEXNOLOGIYALAR Maxsus son, 2023-yil, dekabr
ISSN 2181-4732
27
Conclusion
As can be seen from the graph, this coefficient varies in the range of 3.75 - 6.64, which is
considered a low-level heat carrier - a cooled source, and in our case it depends on the water in the
KKU cooling system and the temperature of the mine water. Since the temperature of the water in the
KKU cooling system is higher than the temperature of the mine water, the conversion factor of using
mine water is about 3.74 - 3.93, and it is 5.14 - 5.77 when using water in the KKU cooling system. it
depends on many factors (season, condition of KKU cooling system, temperature of water entering
the cooling system, etc.).
Therefore, since less work is required to compress the refrigerant, the efficiency of the IN
increases, which means that the compressor, which is the main consumer of IN electricity, needs less
power.
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