Principle and application of the hottest pump 0

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Principle and application of heat pump I. principle introduction and energy conversion analysis of heat pump the so-called heat pump is a mechanical device that uses artificial technology to convert low-temperature heat energy into high-temperature heat energy to achieve heating effect. The heat pump absorbs heat energy from low-temperature heat sources (such as natural air, groundwater, river water, seawater, sewage, etc.) and then converts them into high-temperature heat sources to be released into the required space (or other areas). The device can be used as both heating and cooling equipment, so as to achieve the purpose of one machine for two purposes

the energy conversion of the heat pump unit is to use its compressor to consume certain auxiliary energy (such as electric energy), absorb low-temperature heat energy from the environmental heat source (such as water and air) under the joint action of the compressor and the refrigerant circulating in the heat exchange system, and then convert it into high-temperature heat energy, which is released into the circulating medium (such as water and air) as a high-temperature heat source output. Here, the electric energy is consumed due to the operation of the compressor. The operation of the compressor makes the continuously circulating refrigerant produce different changing states and different effects (i.e. evaporation heat absorption and condensation heat release) in different systems, so as to achieve the function and purpose of recovering the low-temperature heat source to produce the high-temperature heat source

II. Development and application of heat pump in China

the first heat pump unit in Europe was manufactured in 1938. It uses the low-temperature heat source of the river water to supply heat to the city hall, and the output hot water temperature can reach 60oC. Heat pumps are used for heating in winter and cooling in summer. Driven by the energy crisis in 1973, the development of heat pump reached a climax. At present, the theory and technology of heat pump in Europe have been highly developed. This "killing two birds with one stone" and environmentally friendly equipment has been widely used in developed countries such as France, Germany, Japan and the United States

Since the 1980s, there have been many developments in the application and research of heat pumps in various occasions in China. In view of the abundant geothermal resources in China, if the underground hot water after one-time direct utilization or after cooling is used as the low-level heat source of the heat pump, the temperature difference of underground water can be increased and the utilization rate of geothermal energy can be improved, which has been applied in Beijing and Tianjin for a long time. At the same time, this equipment also puts forward an effective solution to the current situation of low energy efficiency and uneven distribution in China

III. technical analysis of heat pump:

1. the heat pump unit can achieve the effect of dual-purpose, that is, heat pump heating in winter and cooling in summer. It not only saves the cost of the refrigeration unit, but also saves the floor area of the boiler room and achieves environmental protection

2. if the owner has a geothermal well, the heat pump device can be used for cascade conversion, and a large number of unqualified personnel can be used to perfunctory delivery inspection procedures to facilitate the full and effective utilization of thermal resources

3. for the energy consumption required for domestic heating and domestic water heating, it is not advisable to rely on direct electric heating, which will cause energy waste. Only heat pump heating and heating can make more effective use of electric energy

4. the use of heat pump technology for heating has no pollution to the atmosphere and the environment, and is energy-efficient. It is a green environmental protection technology and device, which conforms to the current basic policies of China on energy and environmental protection, and plays an invisible role in self publicity for users

IV. economic analysis of heat pump heating

the economy of heat pump is determined from many aspects. Compared with the heating of boiler room, it obviously has the following characteristics:

1. the operation surcharge is small because:

(1) the heat pump device does not need fuel transmission fee, storage fee, slag discharge transportation fee, etc

(2) the maintenance period is long, because the boiler equipment contacts with high-temperature flue gas, the components are very easy to be damaged; However, the heat pump system only has two parts moving, with less wear and tear, and usually does not need any maintenance

(3) both management personnel and labor intensity can be reduced to save wages

2. the direct operation cost (electricity charge) is generally larger than that of coal-fired boilers, which is the main expenditure of heat pumps

3. the initial investment cost of heat pump is usually greater than that of boiler room equipment (it refers to the equipment set solely for heating in winter). Heating equipment with the same capacity is more expensive than boiler equipment. In addition, the initial investment is also related to the scale of the plant and the civil engineering scale investment of the machine room

energy utilization analysis of heat pump:

groundwater has large differential temperature energy storage, which belongs to low-level heat source. It can become useful heat in the life and production process through the conversion of heat pump. The heat pump has an energy efficiency of more than 1 (1:3.2-5.4) and its utilization of energy is far better than that of its American premium rock wool spray insulation coating. It has excellent thermal insulation performance, class a non combustible fire protection performance, excellent sound absorption and noise reduction performance, advanced spray construction technology and green, healthy and environmental protection products

v. relationship between heat pump and energy price

heat pump heating is more advanced than boiler heating. When heating with heat pump and coal, gas, oil and other methods, make a comprehensive comparison with the cost of heating to 10000kcal, We can conclude that:

1. using a heat pump unit: if the cop of the heat pump (which refers to the ratio of its heating capacity to the consumed electric energy) is 4, the power consumption is 2.91kW. If the average price of the electricity charge is 0.5 yuan/kwh (Beijing area), the characteristic of the experimental method of the experimental machine is that it is not necessary to measure the value of the motion characteristic parameter in the experiment, that is, the performance coefficient of the unit), Then the electricity charge is: 2.91x0.5 yuan =1.75 yuan

2. coal: coal can generate about 70% of the heat, so the required fuel is 2.13kg. If the coal price is 0.35 yuan/kg, the cost is: 2.13x0.35 yuan =0.75 yuan

3 Fuel gas: if the fuel gas can generate about 75% of the heat, the required amount of fuel gas is 3.81m3. If the gas price is 0.8 yuan/m3, the cost is: 3.81x0.8 yuan =3.05 yuan

4. fuel oil: the fuel oil can generate about 80% of the heat, and the amount of fuel required is 1.16kg. If the oil price is 2.4 yuan/kg, the cost is: 1.16x2.4 yuan =2.78 yuan

it can be seen that coal heating is the cheapest and gas heating is the most expensive. The power cost of heat pump is directly related to the electricity price. Compared with other heating methods, it also depends on the price of other fuels

however, with the further implementation and implementation of the energy policy, in the actual project, although the operating cost rate of heat pump heating is slightly higher than the direct cost of coal and the initial investment of the overall supporting project is slightly higher, it has the characteristics of high energy utilization rate and environmental protection. As long as the supporting technologies of the system are improved, it will have a good value of wide promotion and application

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