Heat pump units and installations should be considered as devices that carry out a full cycle of refrigerant circulation and control devices, including a drive. Moreover, heat pump units include compact, ready-to-use units, while heat pump units include complexes consisting of several separate devices or blocks. Depending on the type of load on the source and receiver sides, heat pumps can be classified in accordance with table. 1.2.

It has been established that due to the same thermodynamic circular cycle refrigeration units and heat pumps and a slight discrepancy in the temperature ranges of the equipment, heat pumps should be selected directly from the range that is used for refrigeration equipment with some modifications, and only in some cases the development of special units is required.

Table 1.2.

Thermoelectric heat pumps have not yet become widespread due to their low conversion coefficient.

Compression heat pump units

Low power heaters include small water heaters and window air conditioners that include heat pumps. In general, heat pumps, designed primarily to produce heat at a power of 2 ... 3 kW, cannot compete with simple electric heating devices (with an electric support heater) due to high unit costs. Only units designed primarily for the production of cold and heat are of practical importance due to the possibility of simple switching. These are, in particular, window air conditioners with switching (Fig. 1.29).

Such units, as a rule, consist of a refrigeration machine with a sealed housing, an evaporator and a condenser with forced circulation air. With the help of a four-way valve they can switch to the mode heat pump, that is, to provide space heating. Each fan has a device to switch the operation of the evaporator to the condenser, and to move indoor and outdoor air.

Rice. 1.29. A - communication diagram; b - circuit diagram for switching on the air conditioner; heat pump switching diagram; / - capacitor; // - Throttle; Sh compressor; IV- evaporator

Thermal power is 1.5 ... 4.5 kW. The conversion coefficient at a room temperature of 21 ° C and an external temperature of 7.5 ° C rarely exceeds 2.

Part of air conditioners high power, intended for general industrial buildings, is also carried out with switching to heat pump operation.

Compression heat pumps can also be driven by heat engines. In this case, the entire unit consists of a compression heat pump and a heat engine. The conversion of the chemical energy of the fuel into heat occurs directly inside a heat engine (for example, a Stirling engine). In the engine, according to a thermodynamic circular cycle, part of the heat is converted into mechanical energy, which drives its own compression heat pump, thereby increasing the useful temperature level of the low-temperature environment or waste heat. Waste heat from the engine can also be used. Waste heat exchanger depending on temperature conditions it is connected in parallel or in series with the condenser of a compression heat pump or the heat is supplied to special consumers.

In principle, heat engines of all types can be used as drives, but gas and diesel engines are the most convenient, because they operate on natural gas and oil - high-quality primary energy carriers used for heating. The heat produced by such an engine-driven heating system can reduce primary energy consumption by approximately half compared to the conventional method of generating heat by burning fuel.

A conversion factor of 1.8 ... 1.9 can be achieved.

Absorption heat pump units

According to the degree of aggregation, APTs are divided into aggregated (with a constructive combination of all elements into one or more blocks) and non-aggregated (with separately executed APT elements). Aggregates include lithium bromide and APT.

Depending on the scheme for including APT in the technological processes of various industries, they can be divided into autonomous, independent of the technological process diagram, and built-in - with the integration of part of the APT cycle with the technological process.

The number of absorption heat pumps produced so far is small, but high transformation ratios have already been achieved. At the same time, absorption heat pumps can more fully meet the special conditions of heat sources and drive energy than compression ones.

In Germany, for example, absorption heat pumps with a thermal power of 1 ... 3 MW are produced. The transformation ratio depends on the operating temperature and the evaporation temperature. High performance cannot be achieved for small installations (WITH,< 1.5). IN different countries Work is underway to improve small absorption heat pumps.

Heat supply in Russia, with its long and quite severe winters, requires very high fuel costs, which are almost 2 times higher than the cost of electricity supply. The main disadvantages of traditional heat supply sources are low energy, economic and environmental efficiency. In addition, high transport tariffs for the delivery of energy resources aggravate negative factors inherent in traditional heat supply.

A very indicative guideline for assessing the possibility of using heat pump units in Russia is foreign experience. It varies in different countries and depends on climatic and geographical features, the level of economic development, the fuel and energy balance, the ratio of prices for the main types of fuel and electricity, traditionally used heat and power supply systems, etc. Under similar conditions, taking into account the state of the Russian economy, foreign experience follows be considered as a real path of development in the future.

A peculiarity of heat supply in Russia, in contrast to most countries of the world, is the widespread use of centralized heat supply systems in large cities.

Although over the past few decades the production of heat pumps has sharply increased all over the world, HPPs have not yet found widespread use in our country. There are several reasons:

Traditional focus on centralized heat supply;

Unfavorable ratio between the cost of electricity and fuel;

The production of HP is carried out, as a rule, on the basis of the refrigeration machines that are closest in parameters, which does not always lead to optimal characteristics of the HP;

In the recent past there was a very long haul from HP design to its commissioning.

In our country, the design of HP began to be addressed in 1926 /27/. In industry, since 1976, TN worked at a tea factory (Samtredia, Georgia) /13/, at the Podolsk Chemical and Metallurgical Plant (PCMZ) since 1987 /24/, at the Sagarejoy Dairy Plant, (Georgia), in the Moscow region dairy and livestock farm "Gorki-2" since 1963

In addition to industry, VTs are used in mall(Sukhumi) for heat and cold supply, in a residential building (Bucuria village, Moldova), in the Druzhba boarding house (Yalta), climatological hospital (Gagra), Pitsunda resort hall.

Back in the seventies, effective heat recovery using a heat pump unit was carried out at the Pauzhetskaya geothermal station in Kamchatka. TNU successfully used an experimental system for geothermal heat supply to a residential area and the Sredne-Parutinsky greenhouse farm in Kamchatka. In these cases, geothermal sources were used as low-potential energy sources /12/.

The use and especially the production of heat pumps in our country is developing very late. VNIIkholodmash was a pioneer in the field of creation and implementation of heat pumps in the former USSR. In 1986-1989 VNIIkholodmash has developed a number of vapor compression heat pumps with a heating capacity from 1 7 kW to 11.5 MW in twelve water-to-water sizes. Also sea water as a source of low-temperature heat for heat pumps with a heating capacity of 300 - 1000 kW "water-to-air" heat pumps for 45 and 65 kW. Most of the heat pumps of this series have passed the stage of manufacturing and testing, prototypes at five refrigeration engineering plants. Four standard sizes were mass-produced heat pumps with a heating capacity of 14; 100; 300; 8500 kW. Their total production until 1992 was 3000 units. The thermal power of the current fleet of these heat pumps is estimated at 40 MW /16, 17/.

During this period, a whole series of fundamentally new heat pumps were developed - absorption, compression-resorption, compression, operating on butane and water as a working substance, etc.

Subsequently, there was a decline in demand for heat pumps. Many mastered machines and new developments turned out to be unclaimed.

However, in recent years the picture has begun to change. Real economic incentives for energy saving have emerged. This is due to rising energy prices, as well as changes in the ratio of tariffs for electricity and various types of fuel. In many cases, the requirements for environmental friendliness of heat supply systems come to the fore. In particular, this applies to luxury individual houses. New specialized companies have appeared in Moscow, Novosibirsk, Nizhny Novgorod and other cities, designing heat pump installations and producing only heat pumps. Thanks to the efforts of these companies, a fleet of heat pumps with a total thermal capacity of about 50 MW has now been put into operation.

In a real market economy in Russia, heat pumps have the prospect of further expansion of their use, and the production of heat pumps can become commensurate with the production of refrigeration machines of the corresponding classes. This prospect can be assessed when considering the conditions of heat and power supply in the main areas of application of heat pump installations: the housing and communal sector, industrial enterprises, resorts and health resorts. sports complexes, in agricultural production.

In the housing and communal services sector, heat pump units are found greatest application in world and Russian practice, mainly for heating and hot water supply (DHW). Main directions:

Autonomous heat supply from heat pump units;

The use of heat pump units has already been existing systems centralized heating.

For autonomous heat supply In individual buildings, urban areas, and populated areas, mainly vapor-compression heat pumps with a thermal power of 10 - 30 kW are used per unit of equipment in an individual building and up to 5 MW in areas and populated areas.

The program “Development of Non-Conventional Energy in Russia” is currently being implemented. It includes a section on the development of heat pump installations. The development forecast is based on assessments of heat pump manufacturers, as well as their users in the regions of the country, the needs of different capacities and the possibilities of their production. Most of the approximately 30 large projects involve the use of heat pump systems for the housing and communal sector, including in the district heating system.

A number of works are being carried out within the framework of regional programs for energy saving and replacement of traditional heat supply systems with heat pump units: Novosibirsk region, Nizhny Novgorod region, Norilsk, Neryungri, Yakutia, Divnogorsk, Krasnoyarsk Territory. The average annual commissioning of thermal capacity will be about 100 MW.

Under these conditions, the heat production by all operating heat pumps in 2005 amounted to 2.2 million Gcal, and the replacement of organic fuel was 160 thousand tons of standard fuel, the total thermal power annual output 300 MW. Thus, a breakthrough in the spread of heat pump units is planned in Russia.

As for heat pumps with high thermal power from 500 kW to 40 MW, after 2005 the annual commissioning of thermal power averaged 280 MW, and after 2010 - up to 800 MW. This is due to the fact that during this period it is planned to widely use heat pumps in district heating systems.

In agricultural production, the main areas of application of heat pumps are the primary processing of milk and the heat supply of stalls.

On dairy farms, a significant share of energy costs, up to 50%, falls on the drive of compressors of refrigeration machines designed to cool freshly milked milk and heat water for sanitary and technological needs. This combination of heat and cold needs creates favorable conditions for the use of heat pumps. A significant amount of heat is removed with the ventilated air of the stalls, which can be successfully used as a low-potential source for small heat pumps. On livestock farms, a heat pump system provides simultaneous air conditioning in stalls and heat supply to production premises.

Application decentralized systems heat supply based on heat pump installations in areas where heating network are absent, or in new residential areas, it avoids many of the technological, economic and environmental disadvantages of district heating systems. Only regional boiler houses running on gas can be competitive with them in terms of economic parameters.

There are currently a significant number of such installations in operation. And in the future, the need for them will rapidly increase.

Saving, replacement, of fossil fuels using heat pumps occurs due to the beneficial involvement of low-grade heat emissions at thermal power plants. This is achieved in two ways:

Direct use of cooling process water from a thermal power plant as a source of low-grade heat for a heat pump;

Using low-grade heat as a source for a reverse heat pump network water, returned to the thermal power plant, the temperature of which drops to 20 - 25 ° C.

The first method is implemented when the heat pump is located near a thermal power plant, the second - when it is used near heat consumers. In both cases, the temperature level of the low-grade heat source is quite high, which creates the prerequisites for the operation of a heat pump with a high conversion coefficient.

The use of heat pumps in district heating systems can significantly improve the technical and economic performance of urban energy systems, providing:

Increase in thermal power by the amount of recovered heat previously released into the process water cooling system;

Reducing heat loss when transporting network water in main pipelines;

An increase in the heating load by 15 - 20% at the same consumption of primary network water and a reduction in the deficit in network water at central heating stations in microdistricts remote from the thermal power plant;

The emergence of a backup source to cover peak heat loads.

To operate in a centralized heating system, large heat pumps with a heating capacity of several megawatts for installation at heating points and up to several tens of megawatts for use at thermal power plants are required.

At industrial enterprises, heat pump units are used to recover the heat of water circulation systems, the heat of ventilation emissions and the heat of waste water.

With the help of HPP it is possible to transfer most of the waste heat to the heating network, about 50 - 60%. Wherein:

There is no need to expend additional fuel to produce this heat;

The environmental situation would improve;

By lowering the temperature of the circulating water in the turbine condenser, the vacuum will significantly improve and the electrical output from the turbines will increase;

The losses of circulating water and the costs of pumping it will be reduced.

Until recently, it was believed that the use of heat pump units in enterprises supplied with heat from thermal power plants was obviously uneconomical. These estimates are currently being revised. Firstly, they take into account the possibility of using the technologies discussed above in the housing and communal services sector when centralized heating. Secondly, the real price ratios for electricity, heat from thermal power plants and fuel are forcing some enterprises to switch to own generators heat and even electricity. With this approach, the use of heat pump units is most effective. Particularly great fuel savings are achieved by “mini-CHPs” based on a diesel generator running on natural gas, which simultaneously drives the heat pump compressor. Thermal installation At the same time, it provides heating and hot water supply to the enterprise.

The use of a heat pump unit in combination with the use of heat from ventilation emissions is also promising for enterprises. Air heating typical for many industrial enterprises. Ventilation exhaust heat recovery installations make it possible to preheat the air entering the workshop. outside air up to 8 0 C. Temperature of network water heated in a heat pump installation required for heating heating air, does not exceed 70 0 C. Under these conditions, the heat pump installation can operate at a sufficiently high conversion coefficient.

Many industrial enterprises also require artificial refrigeration. Thus, in artificial fiber factories, technological air conditioning is used in the main production workshops to maintain temperature and humidity. Combined heat pump systems: heat pump - refrigeration machine, simultaneously producing heat and cold, are the most economical.

Currently in Russia, HPIs are manufactured to individual orders by various companies. For example, in Nizhny Novgorod, the Triton company produces heat pumps with a heating capacity from 10 to 2000 kW with compressor power from 3 to 620 kW. The working substance is R-142; m≈ 3; TN cost from 5,000 to 300,000 US dollars. Payback period 2 - 3 years.

To this day, Energia CJSC remains practically the only serial manufacturer of vapor compression heat pumps in our country. Currently, the company is mastering the production of absorption heat pump units, as well as turbocompressor heat pumps with large unit power over 3 MW.

The Energia company manufactured and launched about 100 heat pump units of various capacities throughout the former USSR. The first units were installed in Kamchatka.

In Fig. 8.1. Some of the facilities where heat pumps from JSC Energia operate.

CJSC Energia produces heat pumps with a heating capacity of 300 to 2500 kW with a guarantee of operation from 35 to 45 thousand hours. The price of a heat pump is set at 160 - 180 USD. per 1 kW heating output (Q in).

Since its founding, CJSC Energia has put into operation heat pump units of various capacities in the CIS and neighboring countries. In total, CJSC ENERGY from 1990 to 2004 implemented 125 heat pumps of various capacities at 63 facilities in Russia and neighboring countries.

Rice. 8.1. Heat pumps of ZAO Energia installed:

Heat pump installation in secondary school No. 1, Karasuk, Novosibirsk region and heat pump NT - 1000 at the thermal power plant in the village of Rechkunovka, Novosibirsk

Below is a brief summary of the largest facility presented by ZAO Energia, Novosibirsk, table. 8.1..

Table 8.1. Some objects where heat pumps of ZAO Energia operate

Object name	Heat source	Total power, kW	Type of heat pumps	Launch year
Tyumen, Velizhansky water intake, heating of the village	Drinking water 7-9 °C		2 pumps NT-3000
Karasuk, Novosibirsk region, heating high school №1	Ground water 24 °C		2 pumps NKT-300
Gornoaltaisk, Central Control System, building heating	Ground water 7 - 9 °C		1 pump NKT-300
P/household "Mirny", Altai Territory, heating of the village	Ground water 23 °C		3 pumps NKT-300
Lithuania, Kaunas, artificial fiber plant, heating of plant workshops.	Process discharges – water 20 °C		2 pumps NT-3000	1995 1996
Moscow, Interstroyplast (People's Windows), water cooling for extruders	Process water 16 °C		1 pump NT-500
Kazakhstan, Ust-Kamenogorsk, Kaz Zinc JSC, heating feed water before chemical water treatment from 8 to 40 °C	Recycled process water (cooling tower replacement)		1 pump NT-3000
Krasnoyarsk, MSC, heating Institute of Ecology	Yenisei – water in winter is about 2 °C		1 pump NT-500
Yelizovo, Kamchatka region, water intake, building heating	Drinking water 2 - 9 °C		1 pump NKT-300

In the Nizhny Novgorod region, the development and production of HP with

1996 - engaged in the research and production company Triton Ltd. CJSC. Over the past period, HPs of various capacities have been designed and installed:

TN-24, Q = 24 kW, residential heating F = 200 m 2. NIT - groundwater. Installed in the village of Bolshiye Orly, Borsky district, Nizhny Novgorod region, 1998.

TN-45, Q = 45 kW, heating of a complex of administrative buildings, warehouses and a garage, F > 1200 m 2, NIT - groundwater. Installed in the Moscow region, Nizhny Novgorod in 1997. Owner - Symbol LLP.

TN-600, Q = 600 kW, heating, hot water supply of a hotel complex and three cottages, F > 7000 m 2, NIT - groundwater. Installed in Avtozavodsky district, Nizhny Novgorod in 1996. Owner - GAZ.

TN-139, Q = 139 kW, heating, hot water supply industrial building F > 960 m 2, NIT - ground. Installed in Kanavinsky district, Nizhny Novgorod in 1999. Owner - GZhD.

TN-119, Q = 119 kW, heating, hot water dispensary F > 770 m 2, NIT - groundwater. Installed in Borsky district, Nizhny Novgorod region in 1999. Owner: Tsentrenergostroy.

TN-300, Q = 300 kW, heating, school hot water F > 3000 m 2, NIT - groundwater. Put into operation in Avtozavodsky district, Nizhny Novgorod in 1999. Owner is the education department of the district administration.

TN-360, Q = 360 kW, heating, hot water supply of the recreation center F > 4000 m 2, NIT - groundwater. Put into operation in Dalnekonstantinovsky district, Nizhny Novgorod region in 1999. Owner - "Gidromash".

TN-3500, Q = 3500 kW, heating, hot water supply, ventilation of the administrative building of the new depot F > 15000 m 2, NIT - return water, heat supply systems of the Sormovskaya CHPP. Kanavinsky district, Nizhny Novgorod 2000. Owner - GZhD.

Two HP Q = 360 and 200 kW, for the Penza region, 2 Gcal - for Tuapse.

With the participation of specialists from the Institute of High Temperatures of the Russian Academy of Sciences (IHT RAS), a number of pilot demonstration installations and systems using heat pumps for heat supply to various objects have been developed and created /48/.

In the Moscow region village. In 2001, in Gribanovo, on the territory of the testing ground of NPO Astrophysics, a solar heat pump system for heating the laboratory building was put into trial operation. A vertical ground heat exchanger with a total length of about 30 m (technology of JSC Insolar-Invest) was used as a source of low-grade heat for the heat pump. Heating devices- fan coil units and floor heater. Solar collectors provide hot water supply, excess solar heat V summer time are pumped into the ground to accelerate the restoration of its temperature regime.

In 2004 OJSC "Insolar-Invest" an experimental automated heat pump unit (ATNU) designed for heating was put into operation tap water in front of the boilers of the district thermal station of Zelenograd, table. 8.2.

Untreated domestic wastewater accumulated in the receiving tank of the main sewerage system is used as a low-potential heat source. pumping station(GKNS). ATNU is designed to test the technology for recycling the heat of untreated Wastewater, determining the impact of the operation of the installation on the operating parameters of the thermal station, checking the economic efficiency and developing recommendations for the creation of similar installations in the Moscow municipal economy.

Table 8.2. Main design and operational parameters of ATNU

ATNU includes five main parts:

Heat pump thermal unit (HTU);

Pipelines of the low-grade heat collection system (LHS);

Heat exchanger;

Pressure sewerage pipelines;

A group of fecal supply pumps in the State Committee for Water Supply.

Untreated wastewater, having a temperature of 20 0 C, from the receiving tank is supplied by Flygt fecal pumps to a heat exchanger-recovery, where it transfers heat to the intermediate coolant (water), cooling to a temperature of 15.4 0 C, and then returns to the tank. The total wastewater flow is 400 m 3 /h.

The untreated wastewater circulation circuit is designed taking into account the operating practices of pressure pipelines of sewerage systems. The flow rate in the channels of the heat exchanger-recovery ensures that there is no formation of deposits on the heat exchange surfaces.

The intermediate coolant, heated in the heat exchanger-recovery to a temperature of 13 0 C, is supplied to the heat pumps, where it is cooled to a temperature of 8 0 C, giving off heat to the refrigerant of the vapor-compression circuit, and is again sent to the heat exchanger-recovery.

Application of heat pumps in a ring circuit in Russia.

Examples of the use of single heat pump units are mainly considered. These installations include one or more heat pumps that operate independently of each other and perform a specific heat supply function. There is a complex ring heat pump system that allows you to achieve maximum efficiency and savings. Several heat pumps are installed in the ring system, which are used to produce both heat and cold, depending on the needs of different parts of the building. There is very little information about such systems.

Some time ago, a company supplying heat pumps in Russia implemented a project to modernize the heating and air conditioning system in one of the Moscow hotel and entertainment centers /54/. Let's look at how this system works (Fig. 8.2.

The water circuit consists of a water pump and a low-temperature storage tank, due to the volume of which heat accumulation increases and the water temperature in the circuit is stabilized. All VTs are connected to this circuit.

Arrows show the direction of heat movement. Behind the circulation pump, water-to-water heat pumps are installed, which heat the water in the complex’s pools. There can be several pools, of different volumes and with different water temperatures. A heat pump is installed for each pool.

HP "water - air", cooling air in kitchen areas that serve restaurants, bars, cafes, staff canteens. There is always a large heat release in these rooms and the HP cools the air in them, taking heat into the common water circuit.

Rice. 8.2. An example of a ring heat pump.

HP "water - water" is used to utilize excess heat through the hot water supply (DHW) system. Heat is taken from the water of the administrative and office premises. For air conditioning, each of these rooms has its own reversible heat pump for heat or cold. In the warm season, all these pumps will cool the air, and in the cold season, heat it.

All these HPs are combined into one ring with HPs in other parts of the building with their heat needs and surpluses (technical and functional rooms, cafe Restaurant, winter Garden, refrigeration rooms) and heat exchange occurs between them.

For normal operation of the heat pump, the water temperature in the circuit must be in the range from 18 0 C to 35 0 C. If the number of heat pumps operating in the heating mode is equal to the number of heat pumps operating in the cooling mode, then the system does not require heat to be supplied from the outside or removed to the outside . The ring system operates most efficiently at outdoor temperatures from -4 0 C to +14 0 C. The energy costs for operating the entire ring circuit are only the operating costs circulation pump and individual indoor heat pumps. There is no need for expensive sources of thermal energy, gas or electric heaters, or obtaining it from outside.

At lower outside temperatures and a lack of heat in the water circuit, the temperature in it may drop below 18 0 C. Then, to heat the water circuit to the required parameter, you can use external sources - a city heating plant, a boiler or a geothermal heat pump pumping heat from groundwater or from a nearby reservoir. Sources such as groundwater or a river, having a temperature of 4 0 C, will be sufficient to heat the water in the circuit to a level of 18 0 C and, thus, for the normal operation of all heat pumps in the building.

Unfortunately, in Russia this approach is still hampered by high costs at the design stage and the lack of economic measures to stimulate energy-saving and environmentally friendly solutions. Ring heat pump systems can also use other low-grade heat sources. At many sites: large laundries, enterprises that use water in technological processes, there is a significant flow of wastewater, sufficient high temperature. In this case, it makes sense to include a heat pump in the ring system that utilizes this heat.

The water circuit also includes a low-temperature storage tank. The larger the volume of this tank, the more heat, which can be used if necessary, the system is capable of accumulating. The ring system can completely take over the heating function - a monovalent system. However, it is possible to use heat pumps simultaneously with a traditional heating system - a bivalent system. If there is a sufficient number of heat sources connected to the ring at the facility, and with small demands for hot water, the ring system can fully satisfy these needs.

The ring heat pump system can be used exclusively for air conditioning purposes in rooms where there is only such a need. But ring air conditioning systems are especially effective in buildings where there are many rooms with different purposes that require different air temperatures. TN as an air conditioner works more efficiently than many other known air conditioning devices.

The basis for the high efficiency of heat pumps lies precisely in the fact that the energy spent inside the building to produce heat is not dumped “down the drain”, but is used inside the building where it is needed. Heat is accumulated and efficiently transferred within the ring system.

The second important factor of economic efficiency is the possibility of using low-potential “free” heat sources - artesian wells, reservoirs, sewers. With the help of compressors, using a source with a temperature of 4 ° C, we obtain hot water at 50 - 60 0 C, spending 1 kW of electricity to obtain 3 - 4 kW of thermal energy. If using a conventional system steam heating, the efficiency is only 30 - 40%, then with heat pumps the efficiency increases several times.

In particular, in the described hotel and entertainment center the following results were achieved.

Capital costs for the purchase and installation of equipment have been reduced by 13 - 15% compared to the chiller-fan coil system. Simplified system engineering communications compared to a central air conditioning system. A comfortable microclimate has been created in the premises: pressure, humidity and air temperature meet hygienic requirements. Total costs for heating and hot water supply are reduced by more than 50% compared to central heating.

A ring heat pump system does not require complex and expensive control and monitoring devices to optimize its operation. It is enough to use several thermostats and thermostats to maintain the temperature in the water circuit within specified limits. For additional convenience and visual control, you can use expensive automation.

At a given temperature range in the water circuit of the ring system of 18 - 35 0 C, condensation does not form on the pipes and there is no noticeable heat loss. This is an important factor when the system is significantly branched (distribution, risers, connections, of which there can be quite a lot in buildings with complex architecture).

When using HP in a room ventilation system, the number and total length of air ducts can be reduced compared to central installations air conditioning. Heat pump units are located directly in the air-conditioned rooms or in those adjacent to them, that is, the air is conditioned directly on site. This avoids transporting finished air through long air ducts.

In Russia, the first such TH-based system was installed in 1990 at the Iris Congress Hotel. This is a ring bivalent air conditioning system from the American company ClimateMaster. For heating the hotel uses a heated kitchen, laundry, technical premises, refrigeration units and freezers, heat exchange occurs during air conditioning of hotel rooms, conference rooms, fitness centers, restaurants, and administrative premises. 15 years of operation of the system have shown the reliability of the equipment and the feasibility of its use in our climate.

When designing a heat pump system for an object, it is necessary, first of all, to study all possible low-potential heat sources and all possible consumers of high-potential heat at this object, to evaluate all heat inflows and all heat losses. You should choose those sources for disposal where heat is released fairly evenly and over a long period of time. Accurate and accurate calculations will ensure stable and cost-effective operation of the HP. The total capacity of waste heat pumps should not be uselessly excessive. The system must be balanced, but this does not mean that the total powers of heat sources and consumers should be close, they can vary, and their ratio can also change significantly when operating conditions of the system change. The flexibility of the system allows you to choose when designing it best option and lay down the possibility of its further expansion. It is also necessary to take into account the peculiarities of the climatic conditions of the region. Climatic conditions are the key to choosing an effective climate system.

In southern latitudes, the main task is to cool the air and release heat outside, the utilization of which for heating is pointless. Traditional chiller systems - fan coils or similar - are quite suitable here. IN northern latitudes required too a large number of energy for heating the facility, a lot of high-potential heat that will have to be supplied to the system. Therefore, it will be necessary to install a bivalent system, a HP in combination with a heating system. IN temperate climate in middle latitudes it is advisable to use a monovalent ring system, where its efficiency is maximum.

Today there is a widespread opinion that TN is too expensive. The costs of installing and assembling equipment are high, and given the current heat prices in Russia, the payback period is too long. However, practice shows that installing heat pump systems at large and medium-sized facilities allows you to save 10 - 15% on capital investments, not to mention operating costs. In addition, ring systems minimize the consumption of energy resources, the prices of which are increasing at an ever faster rate.

According to Research.Techart calculations, in 2009, 5.3 MW of heat pumps were installed in Russia. The dynamics of the Russian geothermal pump market, according to Research.Techart forecasts, will be low in the medium term, which is associated with the crisis in the economy. However, in some regions the market can develop very actively.

The trend towards increasing demand from the infrastructure and housing sectors will continue, and the main volume of sales will be HSPs with a thermal capacity of 15 - 38 kW. The consumption structure regarding the types of PTN will not change. An increase in the share of domestic products in the total market volume is predicted.

In the long term, the leading factor in market development will be the implementation of the state energy strategy. After 2016 it is predicted active growth market. In area technical characteristics a transition to PHP with carbon refrigerants is expected. At the same time, the consumption of both low- and medium-power and high-power heat pumps will increase, which is due to the prospects for using wastewater heat recovery systems. Against the backdrop of increasing demand, active development of the domestic production base will begin - number Russian manufacturers will increase and they will occupy a leading position in the market.

By 2020, the PTN market volume may reach 8,000 - 11,000 units, 460 - 500 MW. Forecast of the PTN market volume for 2030 - the moment of completion of the implementation of the current Energy Strategy of Russia - 11,000 - 15,000 units, 500 - 700 MW.

Having refrigerators and air conditioners in their home, few people know that the principle of operation of a heat pump is implemented in them.

About 80% of the power produced by a heat pump comes from ambient heat in the form of diffuse solar radiation. It is this pump that simply “pumps” it from the street into the house. The operation of a heat pump is similar to the principle of operation of a refrigerator, but the direction of heat transfer is different.

Simply put…

To cool the bottle mineral water, You put it in the refrigerator. The refrigerator must “take” part of the thermal energy from the bottle and, according to the law of conservation of energy, move it somewhere and give it away. The refrigerator transfers heat to a radiator, usually located on the rear wall. At the same time, the radiator heats up, releasing its heat into the room. In fact, it heats the room. This is especially noticeable in small minimarkets in the summer, when several refrigerators are turned on in the room.

We invite you to dream up your imagination. Let's assume that we will constantly put warm objects in the refrigerator, and by cooling them, it will heat the air in the room. Let's go to the “extremes”... Let's place the refrigerator in window opening with the freezer door open to the outside. The refrigerator radiator will be located indoors. During operation, the refrigerator will cool the air outside, transferring the “taken” heat into the room. This is how a heat pump works, taking dispersed heat from the environment and transferring it into the room.

Where does the pump get heat?

The operating principle of a heat pump is based on the “exploitation” of natural low-potential heat sources from the environment.

They may be:

• just outside air;
• warmth of water bodies (lakes, seas, rivers);
• warmth of the soil, groundwater (thermal and artesian).

How does a heat pump and the heating system with it work?

The heat pump is integrated into the heating system, which consists of 2 circuits + a third circuit - the system of the pump itself. A non-freezing coolant circulates along the external circuit, which absorbs heat from the surrounding space.

Getting into the heat pump, or more precisely its evaporator, the coolant releases an average of 4 to 7 °C to the heat pump refrigerant. And its boiling point is -10 °C. As a result, the refrigerant boils and then transforms into a gaseous state. The coolant of the external circuit, already cooled, goes to the next “turn” in the system to set the temperature.

The functional circuit of the heat pump includes:

• evaporator;
• compressor (electric);
• capillary;
• capacitor;
• refrigerant;
• thermostatic control device.

The process looks something like this!

The refrigerant that has “boiled” in the evaporator is supplied through a pipeline to a compressor powered by electricity. This "hard worker" compresses the gaseous refrigerant to high pressure, which, accordingly, leads to an increase in its temperature.

The now hot gas then enters another heat exchanger, which is called a condenser. Here, the heat of the refrigerant is transferred to the room air or coolant, which circulates through the internal circuit of the heating system.

The refrigerant cools while simultaneously turning into a liquid. It then passes through the capillary pressure reducing valve, where it “loses” pressure and returns to the evaporator.

The cycle is closed and ready to repeat!

Approximate calculation of the heating capacity of the installation

Within an hour, up to 2.5-3 m 3 of coolant flows through the external collector through the pump, which the earth can heat by ∆t = 5-7 °C.

To calculate the thermal power of such a circuit, use the formula:

Q = (T_1 - T_2)*V_heat

V_heat - volumetric flow rate of coolant per hour (m^3/hour);

T_1 - T_2 - temperature difference between inlet and inlet (°C).

Types of heat pumps

Heat pumps are classified according to the type of dissipated heat used:

• ground-water (use closed ground contours or deep geothermal probes and water system space heating);
• water-water (they use open wells for the intake and discharge of groundwater - the external contour is not looped, internal system heating - water);
• water-air (use of external water circuits and an air-type heating system);
• (use of dissipated heat from external air masses complete with an air heating system for the house).

Advantages and benefits of heat pumps

Cost effective. The operating principle of a heat pump is based not on the production, but on the transfer (transportation) of thermal energy, so it can be argued that its efficiency is greater than one. What nonsense? - you say. The topic of heat pumps includes a value - the heat conversion coefficient (HCT). It is by this parameter that units of similar types are compared with each other. Its physical meaning is to show the ratio of the amount of heat received to the amount of energy expended for this. For example, with KPT = 4.8, the 1 kW of electricity expended by the pump will allow us to obtain 4.8 kW of heat free of charge, that is, free of charge from nature.

Universal ubiquity of application. Even in the absence of accessible power lines, the heat pump compressor can be powered by a diesel drive. And “natural” heat is available in every corner of the planet - the heat pump will not remain “hungry”.

Environmentally friendly use. There are no combustion products in the heat pump, and its low energy consumption “operates” power plants less, indirectly reducing harmful emissions from them. The refrigerant used in heat pumps is ozone-friendly and does not contain chlorocarbons.

Bidirectional operating mode. The heat pump can winter time heat the room, and cool it in the summer. The “heat” taken from the room can be used effectively, for example, to heat water in a swimming pool or in a hot water system.

Operational safety. In the principle of operation of a heat pump, you will not consider dangerous processes. The absence of open fire and harmful emissions that are dangerous to humans, and the low temperature of coolants make the heat pump a “harmless” but useful household appliance.

Full automation of the room heating process.

Some nuances of operation

Effective use of the heat pump operating principle requires compliance with several conditions:

• the room that is heated must be well insulated (heat loss up to 100 W/m2) - otherwise, taking heat from the street, you will heat the street at your own expense;
• Heat pumps are advantageous to use for low-temperature heating systems. Underfloor heating systems (35-40 °C) are ideal for such criteria. The heat conversion coefficient significantly depends on the temperature ratio of the input and output circuits.

Let's summarize what has been said!

The essence of the principle of operation of a heat pump is not in the production, but in the transfer of heat. This allows you to obtain a high coefficient (from 3 to 5) of thermal energy conversion. Simply put, every 1 kW of electricity used will “transfer” 3-5 kW of heat into the house. Anything else that needs to be said?

A heat pump is an entire heating system capable of heating a private house no worse than the traditional heating we are used to. It is clear that in order to put the pump into operation, you first need to install it correctly.

All heat pumps, depending on what natural source they take heat from, are divided into three main types: ground-water, water-water, air-water.

The installation of each of these types has its own nuances and features. - enough complex design and its installation is a labor-intensive process that must be approached with great responsibility. In this article we will look at what you need to pay attention to when installing various types heat pumps.

Rules for installing a ground-water heat pump

Scheme of operation of the ground-water system pump (click to enlarge)

The soil is a source of heat. Having gone 5 meters into the ground, you can see that the temperature there remains almost the same whole year(in most regions of Russia – 8-10°C).

Thanks to this, the heating will be highly efficient. The system works as follows: a ground heat exchanger located in the ground collects energy, which accumulates in the coolant, after which it moves to the heat pump and returns back.

Diagram of the operation of the water-water system pump (click to enlarge)

Some of the energy emitted by the sun remains underwater, especially in the water column. Special pipes weighed down with a load are laid at the bottom of the reservoir or in the bottom soil.

High coolant temperature in winter period provides greater efficiency and heat transfer. But, alas, it is not suitable for installation in private homes.

More or less for small houses The option with a well is suitable. A special pump pumps water from the well into the evaporator, after which the water is drained into another well, located downstream and deepened into the underground layer by 15 meters.

Expert advice: Before using the water-water system, it is necessary to prevent debris from entering the evaporator and protect it from rust, and also install a filter. If the water is rich in salts, then the installation of an intermediate heat exchanger with the circulation of clean water or antifreeze in it is required.

However, if the water from the well is poorly drained, a small flood and flooding of the pump is possible.

Rules for installing an air-water heat pump

Diagram of the operation of the air-water system pump (click to enlarge)

Less popular than ground-water due to the fact that in winter it is impossible to extract enough heat from the air. -20°C is the operating limit of the heat pump, after which the additional heat generator comes into operation.

Basic installation diagrams:

1. Monoblock structures are installed indoors, all equipment is assembled in one building. A flexible air duct connects the mechanism to the street. External monoblocks are also manufactured.
2. Split technology includes two blocks connected to each other.

One is located on the street, the other is in a building. The first one has a fan with an evaporator, and the second one has automation and a condenser. The compressor can be installed both indoors and outdoors.

Take note: When choosing air heat pumps, keep in mind that when it gets cold, the power is lost almost twice.

New heat pumps of this type have introduced a function that allows them to collect heat from the room, ventilation emissions and flue gases. Thanks to this, it is possible to heat the room and heat running water.

When buying a heat pump, you need to focus on the specific needs of your home.

Ideally, you need to know the heat loss of the house and the climate in which the home is located. This data is important in order to correctly select the power of the heat pump and its model.

But you also need to remember that when choosing a heat pump, you also need to correctly select all the components of the heating system in which the heat pump will operate.

It is impossible to find a universal heat pump, since each heating system is unique.
And yet, all heating systems with this device have common criteria that affect the heat pump connection diagram:

• the presence of an additional heat source (heating boiler, solar battery, bake);
• the presence of water circuits (warm floors, fan coil units, radiators);
• the need for hot water supply;
• availability of air conditioning;
• presence of a ventilation system;
• heat pump type.

If you take into account these nuances and your individual needs, you can do right choice and become the owner of a reliable, durable and economical heating system.

Watch the video that shows the entire heat pump installation process:

Schematic diagram of a heat pump installation (a and an image in the T - s diagram of its reversible cycle (b.  

Heat pump units can be successfully and efficiently used in installations of combined winter heating and summer air conditioning; in installations for the combined production of cold and heat; in evaporation desalination and rectification plants; at hydroelectric power stations to use the heat of air and hydrogen cooling electric generators; at oil refineries and petrochemical plants when using the heat of hot oil products and hot water(t 60 H - 120 C) to produce water steam at a pressure of 10 kg / ezh2 and hot water at a temperature of 130 - 150 C.  

The heat pump system, which serves to heat the spa hall in winter, uses sea water as a heat source. How will the thermal power of the installation change if it operates according to an internal reversible Carnot cycle at the same temperature differences in the evaporator and condenser? How will it change heating coefficient, if external irreversibility is eliminated in the heat exchangers of an installation operating on a reverse Carnot cycle.  

It is most advisable to use heat pump installations to satisfy a constant heat load in the presence of a constant source of low-grade heat and with a relatively small required heat increase, i.e. at a small & TTS-Ta value or at a TS/TB ratio close to unity. Such conditions usually occur when a relatively constant industrial heat load of low potential or a hot water supply load is satisfied using heat pump installations, in the presence of low-potential industrial heat waste with a temperature of 20 - 40 C and above. Under these conditions, heat pump units, both in terms of energy indicators (fuel consumption) and reduced costs, are quite competitive with highly economical boiler systems.  

A heat pump plant consists of a heat pump, an installation for selecting heat from its source and other equipment.  

A heat pump system usually has a higher initial cost than boiler-based heating.  

It is most advisable to use heat pump installations to satisfy a constant heat load in the presence of a constant source of low-grade heat and with a relatively small required heat increase, i.e. with a small &TTB-Ts value or with a TB/TV ratio close to unity. Such conditions usually occur when a relatively constant industrial heat load of low potential or a hot water supply load is satisfied using heat pump installations, in the presence of low-potential industrial heat waste with a temperature of 20 - 40 C and above. Under these conditions, heat pump units, both in terms of energy indicators (fuel consumption) and reduced costs, are quite competitive with highly economical boiler systems.  

Two-stage heat pump units are sometimes used in district heating systems that cover the heating load.  

The first use of a vapor-compression ammonia heat pump system for space heating was in 1930. Since then, a large number of heat pumps have been built. There is reason to believe that the use of heat pumps will become more widespread in the future.  

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