Ministry of Education of the Russian Federation

Federal State Budgetary Educational Institution of Higher Professional Education "Magnitogorsk State Technical University

them. G.I. Nosov"

(FSBEI HPE "MSTU")

Department of Thermal Power and Energy Systems

ABSTRACT

in the discipline "Introduction to Direction"

on the topic: “Centralized and decentralized heat supply”

Completed by: student Sultanov Ruslan Salikhovich

Group: ZEATB-13 “Thermal power engineering and heating engineering”

Code: 140100

Checked by: Evgeniy Borisovich Agapitov, Doctor of Technical Sciences

Magnitogorsk 2015

1.Introduction 3

2.District heating 4

3.Decentralized heat supply 4

4.Types of heating systems and principles of their operation 4

5.Modern heating and hot water supply systems in Russia 10

6.Prospects for the development of heat supply in Russia 15

7. Conclusion 21

Introduction

Living in temperate latitudes where the main part of the year is cold, it is necessary to provide heat supply to buildings: residential buildings, offices and other premises. Heat supply ensures comfortable living if it is an apartment or house, productive work if it is an office or warehouse.

First, let’s figure out what is meant by the term “Heat supply”. Heat supply is the supply of hot water or steam to the heating systems of a building. The usual sources of heat supply are thermal power plants and boiler houses. There are two types of heat supply to buildings: centralized and local. With centralized supply, individual areas (industrial or residential) are supplied. For the efficient operation of a centralized heating network, it is built by dividing it into levels, the work of each element is to perform one task. With each level, the element's task decreases. Local heat supply is the supply of heat to one or more houses. Centralized heating networks have a number of advantages: reduction of fuel consumption and cost reduction, use of low-grade fuel, improvement of the sanitary condition of residential areas. The centralized heat supply system includes a source of thermal energy (CHP), a heating network and heat-consuming units. A CHP plant combines the production of heat and energy. Sources of local heat supply are stoves, boilers, water heaters.

Heat supply systems differ in different temperatures and water pressure. This depends on customer requirements and economic considerations. As the distance over which heat must be “transferred” increases, economic costs increase. Currently, heat transfer distances are measured in tens of kilometers. Heat supply systems are divided according to the volume of heat loads. Heating systems are classified as seasonal, and hot water supply systems are classified as permanent.

District heating

Centralized heat supply is characterized by the presence of an extensive branched subscriber heating network with power supply to numerous heat receivers (factories, enterprises, buildings, apartments, residential premises and others).

The main sources for centralized heat supply are: - combined heat and power plants (CHP), which also simultaneously generate electricity; - boiler rooms (in heating and steam).

Decentralized heat supply

Decentralized heat supply is characterized by a heat supply system in which the heat source is combined with a heat receiver, that is, the heating network is insignificant or absent altogether. If separate individual electric or local heating heat sinks are used in the premises, then such heat supply will be individual (an example would be heating the own small boiler room of the entire building). The power of such heat sources, as a rule, is very small and depends on the needs of their owners. The heating capacity of such individual heat sources is no more than 1 Gcal/h or 1.163 MW.

The main types of such decentralized heating:

Electrical, namely: - direct; - accumulation;

- heat pump;

- stove.

Small boiler houses.

Types of heating systems and principles of their operation District heating consists of three interconnected and sequential stages: preparation, transportation and use of the coolant. In accordance with these stages, each system consists of three main links: a heat source (for example, a combined heat and power plant or boiler house), heat networks (heat pipelines) and heat consumers. In decentralized heat supply systems, each consumer has its own heat source.

The advantages of a steam heating system are its significantly lower cost and metal consumption compared to other systems: when condensing 1 kg of steam, approximately 535 kcal are released, which is 15-20 times more quantity heat released when 1 kg of water cools in heating devices, and therefore the steam lines have a significantly smaller diameter than the pipelines of a water heating system. In steam heating systems, the surface area of ​​the heating devices is smaller. In rooms where people stay periodically (industrial and public buildings), a steam heating system will make it possible to produce heating intermittently and without the risk of freezing of the coolant with subsequent rupture of pipelines.

The disadvantages of the steam heating system are its low hygienic qualities: dust in the air burns on heating devices heated to 100°C or more; it is impossible to regulate the heat transfer of these devices and for most of the heating period the system must operate intermittently; the presence of the latter leads to significant fluctuations in air temperature in heated rooms. Therefore, steam heating systems are installed only in those buildings where people stay periodically - in bathhouses, laundries, shower pavilions, train stations and clubs.

Air heating systems consume little metal, and they can simultaneously ventilate the room while heating it. However, the cost of an air heating system residential buildings higher than other systems.

Water heating systems are more expensive and metal intensive compared to steam heating, but they have high sanitary and hygienic qualities, which ensure their widespread use. They are installed in all residential buildings more than two floors high, in public buildings and in most industrial buildings. Centralized regulation of the heat transfer of devices in this system is achieved by changing the temperature of the water entering them.

Water heating systems are distinguished by the method of moving water and design solutions.

Based on the method of moving water, systems with natural and mechanical (pumping) stimulation are distinguished. Water heating systems with natural impulse. The schematic diagram of such a system consists of a boiler (heat generator), a supply pipeline, heating devices, a return pipeline and an expansion vessel. The water heated in the boiler enters the heating devices, transfers part of its heat to them to compensate for heat losses through the external enclosures of the heated building, then returns to the boiler and then the water circulation is repeated. Its movement occurs under the influence of a natural impulse that arises in the system when heating water in the boiler.

The circulating pressure created during the operation of the system is spent on overcoming the resistance to the movement of water through the pipes (from the friction of water against the walls of the pipes) and on local resistance (in bends, taps, valves, heating devices, boilers, tees, crosses, etc.) .

The higher the speed of water movement in the pipes, the greater the magnitude of these resistances (if the speed doubles, then the resistance quadruples, i.e., in a quadratic relationship). In systems with natural impulse in buildings of small number of floors, the magnitude of the effective pressure is small, and therefore high speeds of water movement in the pipes cannot be allowed in them; therefore, the pipe diameters must be large. The system may not be economically viable. Therefore, the use of natural circulation systems is allowed only for small buildings. The range of such systems should not exceed 30 m, and the value of k should be at least 3 m.

As the water in the system heats up, its volume increases. To accommodate this additional volume of water in heating systems, an expansion vessel 3 is provided; in systems with overhead wiring and natural impulse, it simultaneously serves to remove from them the air released from the water when it is heated in boilers.

Pump driven water heating systems. The heating system is always filled with water and the task of the pumps is to create the pressure necessary only to overcome the resistance to the movement of water. In such systems, natural and pumping drives operate simultaneously; total pressure for two-pipe systems with overhead distribution, kgf/m2 (Pa)

For economic reasons, it is usually taken in the amount of 5-10 kgf/m2 per 1 m (49-98 Pa/m).

The advantages of systems with pumping stimulation are reduced costs for pipelines (their diameter is smaller than in systems with natural stimulation) and the ability to supply heat to a number of buildings from one boiler room.

The devices of the described system, located on different floors of the building, operate under different conditions. The pressure p2, which ensures water circulation through the device on the second floor, is approximately twice as high as the pressure p1 for the device on the lower floor. At the same time, the total resistance of the pipeline ring passing through the boiler and the second floor appliance is approximately equal to the resistance of the ring passing through the boiler and the first floor appliance. Therefore, the first ring will work with excess pressure, and the device on the second floor will receive more water, than is necessary according to the calculation, and accordingly the amount of water passing through the device on the first floor will decrease.

As a result, overheating will occur in the room heated by this device on the second floor, and underheating in the room on the first floor. To eliminate this phenomenon, special methods for calculating heating systems are used, and they also use double adjustment taps installed on the hot supply to the devices. If you close these taps at the appliances on the second floor, you can completely extinguish the excess pressure and thereby regulate the water flow for all appliances located on the same riser. However, uneven distribution of water in the system is also possible in individual risers. This is explained by the fact that the length of the rings and, consequently, their total resistance in such a system is not the same for all risers: the ring passing through the riser (closest to the main riser) has the least resistance; The longest ring passing through the riser has the greatest resistance.

Water can be distributed over individual risers by appropriately adjusting the plug (pass-through) taps installed on each riser. To circulate water, two pumps are installed - one working, the second - spare. Near the pumps, a closed bypass line with a valve is usually made. In the event of a power outage and the pump stops, the valve opens and the heating system operates with natural circulation.

In a pump driven system, the expansion tank is connected to the system before the pumps and therefore accumulated air cannot be removed through it. To remove air in previously installed systems, the ends of the supply risers were continued with air pipes on which valves were installed (to shut off the riser for repairs). The air line at the point of connection to the air collector is made in the form of a loop that prevents the circulation of water through the air line. Currently, instead of this solution, air valves are used, screwed into the top plugs of radiators installed on the top floor of the building.

Heating systems with bottom wiring are more convenient to use than systems with top wiring. So much heat is not lost through the supply line and water leaks from it can be detected and eliminated in a timely manner. The higher the heating device is placed in systems with lower wiring, the greater the pressure available in the ring. How longer length ring, the greater its total resistance; therefore, in a system with lower wiring, the excess pressures of devices on the upper floors are much less than in systems with upper wiring and, therefore, their adjustment is simpler. In systems with bottom wiring, the magnitude of the natural impulse is reduced due to the fact that, due to cooling in the supply risers, a braking movement from top to bottom occurs, therefore the total pressure acting in such systems is

Currently, single-pipe systems in which radiators are connected by both connections to one riser have become widespread; Such systems are easier to install and provide more uniform heating of all heating devices. The most common is a single-pipe system with bottom wiring and vertical risers.

The riser of such a system consists of a lifting and lowering part. Three-way valves can pass a calculated amount or part of the water into the devices; in the latter case, the rest of the water passes, bypassing the device, through the closing sections. The connection between the rising and falling parts of the riser is made by a connecting pipe laid under the windows of the upper floor. In the upper plugs of devices located on top floor, install air valves through which the mechanic removes air from the system during startup of the system or when abundantly replenishing it with water. In single-pipe systems, water flows through all fixtures in sequence, and therefore they must be carefully adjusted. If necessary, adjustment of the heat transfer of individual devices is carried out using three-way valves, and the water flow through individual risers is carried out using pass-through (plug) valves or by installing throttling washers in them. If an excessively large amount of water flows into the riser, then the first heating devices in the riser along the flow of water will give off more heat than is necessary according to the calculation.

As is known, the circulation of water in the system, in addition to the pressure created by the pump and natural impulse, is also obtained from the additional pressure Ap resulting from the cooling of water when moving through the pipelines of the system. The presence of this pressure made it possible to create apartment water heating systems, the boiler of which is not buried, but is usually installed on the kitchen floor. In such cases, the distance, therefore, the system works only due to the additional pressure resulting from cooling the water in the pipelines. The calculation of such systems differs from the calculation of building heating systems.

Apartment water heating systems are currently widely used instead of stove heating in one- and two-story buildings in gasified cities: in such cases, automatic gas water heaters (AGW) are installed instead of boilers, providing not only heating, but also hot water supply.

Comparison of modern heat supply systems of a thermal hydrodynamic pump type TC1 and a classic heat pump

After installing hydrodynamic heat pumps, the boiler room will look more like a pumping station than a boiler room. There will be no need for a chimney pipe. There will be no soot and dirt, the need for maintenance personnel will be significantly reduced, the automation and control system will completely take over the processes of managing heat production. Your boiler room will become more economical and high-tech.

Schematic diagrams:

Unlike heat pump, which can provide maximum coolant with a temperature of up to +65 °C, a hydrodynamic heat pump can heat the coolant up to +95 °C, which means it can be quite easily integrated into an existing heating system of a building.

In terms of capital costs for the heat supply system, a hydrodynamic heat pump is several times cheaper than a heat pump, because does not require a low-grade heat circuit. Heat pumps and thermal hydrodynamic pumps, similar in name but different in principle of converting electrical energy into heat.

Like a classic heat pump, a hydrodynamic heat pump has a number of advantages:

· Economical (a hydrodynamic heat pump is 1.5-2 times more economical than electric boilers, 5-10 times more economical than diesel boilers).

· Absolutely environmentally friendly (possibility of using a hydrodynamic heat pump in places with limited maximum permissible limits).

· Complete fire and explosion safety.

· Does not require water treatment. During operation, as a result of the processes taking place in the heat generator of a hydrodynamic heat pump, degassing of the coolant occurs, which has a beneficial effect on the equipment and devices of the heat supply system.

· Quick installation. If there is supplied electrical power, installation of an individual heating point using a hydrodynamic heat pump can be completed in 36-48 hours.

· Payback period from 6 to 18 months, due to the possibility of installation in an existing heat supply system.

· Time until major repairs is 10-12 years. The high reliability of a hydrodynamic heat pump is built into the design and is confirmed by many years of trouble-free operation of hydrodynamic heat pumps in Russia and abroad.

Autonomous heating systems

Autonomous heat supply systems are designed for heating and hot water supply of single-family and semi-detached residential buildings. An autonomous heating and hot water supply system includes: a heat supply source (boiler) and a pipeline network with heating devices and water fittings.

Advantages autonomous systems heat supply are as follows:

· absence of expensive external heating networks;

· the ability to quickly install and put into operation heating and hot water supply systems;

· low initial costs;

· simplification of solving all issues related to construction, since they are concentrated in the hands of the owner;

· reduction of fuel consumption due to local regulation of heat supply and absence of losses in heating networks.

Such heating systems, according to the principle of accepted schemes, are divided into schemes with natural coolant circulation and schemes with artificial coolant circulation. In turn, schemes with natural and artificial coolant circulation can be divided into single- and double-pipe. According to the principle of coolant movement, circuits can be dead-end, associated or mixed.

For systems with a natural flow of coolant, we recommend designs with overhead wiring, with one or two (depending on the load and design features of the house) main risers, with an expansion tank installed on the main riser.

A boiler for single-pipe systems with natural circulation can be located on the same level as the lower heating devices, but it is better if it is buried, at least to the level of a concrete slab, in a pit or installed in the basement.

The boiler for two-pipe heating systems with natural circulation must be buried in relation to the lower heating device. The depth of burial is specified by calculation, but not less than 1.5-2 m. Systems with artificial (pump) stimulation of the coolant have a wider range of applications. It is possible to design circuits with upper, lower and horizontal coolant distributions.

Heating systems are:

· water;

· air;

· electric, including those with a heating electric cable laid in the floor of heated rooms, and battery-powered heat stoves (designed with permission from the energy supply organization).

Water heating systems are designed vertically with heating devices installed under window openings and with heating pipelines embedded in the floor structure. If there are heated surfaces, up to 30% of the heating load should be provided by heating devices installed under window openings.

Apartment air heating systems combined with ventilation should allow operation in full circulation mode (no people present) only on external ventilation (intensive household processes) or on a mixture of external and internal ventilation in any desired ratios.

Modern heating and hot water supply systems in Russia

Heating devices are an element of the heating system designed to transfer heat from the coolant to the air to the enclosing structures of the serviced premises.

A number of requirements are usually put forward for heating devices, on the basis of which one can judge the degree of their perfection and make comparisons.

· Sanitary and hygienic. Heating devices should, if possible, have a lower body temperature and have smallest area horizontal surface to reduce dust deposits, allowing dust to be easily removed from the body and the enclosing surfaces of the room around them.

· Economic. Heating devices must have the lowest reduced costs for their manufacture, installation, operation, and also have the lowest metal consumption.

· Architectural and construction. The appearance of the heating device must correspond to the interior of the room, and the volume they occupy must be the smallest, i.e. their volume per unit heat flow, should be the smallest.

· Production and installation. Maximum mechanization of work during the production and installation of heating devices must be ensured. Heating appliances. Heating devices must have sufficient mechanical strength.

· Operational. Heating devices must ensure controllability of their heat transfer and provide heat resistance and water resistance at the maximum permissible hydrostatic pressure inside the device under operating conditions.

· Thermal engineering. Heating devices must provide the highest density of specific heat flux per unit area (W/m).

Water heating systems

The most common heating system in Russia is water. In this case, heat is transferred to the premises by hot water contained in heating devices. The most common way is water heating with natural circulation of water. The principle is simple: water moves due to differences in temperature and density. Lighter hot water rises upward from the heating boiler. Gradually cooling down in the pipeline and heating devices, it becomes heavier and tends downward, back to the boiler. The main advantage of such a system is independence from power supply and fairly simple installation. Many Russian craftsmen cope with its installation on their own. In addition, the low circulation pressure makes it safe. But for the system to operate, pipes of increased diameter are required. At the same time, reduced heat transfer, limited range and a large amount of time required to start make it imperfect and suitable only for small houses.

More modern and reliable heating schemes with forced circulation. Here the water is driven by the operation of a circulation pump. It is installed on the pipeline supplying water to the heat generator and sets the flow rate.

Quick start-up of the system and, as a result, quick heating of the premises is the advantage of the pumping system. The disadvantages are that it does not work when the power is turned off. And this can lead to freezing and depressurization of the system. The heart of a water heating system is the heat supply source, the heat generator. It is he who creates the energy that provides heat. Such a heart is boilers using different types of fuel. The most popular are gas boilers. Another option is a diesel fuel boiler. Electric boilers are distinguished by the absence of open flames and combustion products. Solid fuel boilers are not convenient to use due to the need for frequent firing. To do this, you need to have tens of cubic meters of fuel and storage space. And add here the labor costs for loading and preparation! In addition, the heat transfer mode of a solid fuel boiler is cyclical, and the air temperature in heated rooms fluctuates noticeably throughout the day. A place to store fuel reserves is also necessary for liquid fuel boilers.

Aluminum, bimetallic and steel radiators

Before choosing any heating device, you need to pay attention to the indicators that the device must meet: high heat transfer, low weight, modern design, low capacity, low weight. The most important characteristic of a heating device is heat transfer, that is, the amount of heat that should be present in 1 hour per 1 square meter of heating surface. The best device is considered to have a higher this indicator. Heat transfer depends on many factors: heat transfer medium, design of the heating device, installation method, paint color, speed of water movement, speed of air washing the device. All devices of the water heating system are divided by design into panel, sectional, convectors and columnar aluminum or steel radiators.

Panel heating devices

Manufactured from high-quality cold-rolled steel. They consist of one, two or three flat panels, inside of which there is a coolant, they also have ribbed surfaces that are heated by the panels. Heating of the room occurs faster than when using sectional radiators. The above panel water heating radiators come with side or bottom connections. The side connection is used when replacing an old radiator with a side connection or if the slightly unaesthetic appearance of the radiator does not interfere with the interior of the room.

Ph.D. A.V. Martynov, associate professor,
Department of “Industrial Heat and Power Systems”,
Moscow Energy Institute (TU)

(report at the second scientific and practical conference “Heat supply systems. Modern solutions", Zvenigorod, May 16-18, 2006).

Decentralized consumers, who, due to large distances from thermal power plants, cannot be covered by centralized heat supply, must have a rational (efficient) heat supply that meets the modern technical level and comfort.

The scale of fuel consumption for heat supply is very large. Currently, the heat supply to industrial, public and residential buildings is carried out at approximately 40+50% from boiler houses, which is ineffective due to their low efficiency (in boiler houses the fuel combustion temperature is approximately 1500 °C, and heat is supplied to the consumer at significantly higher temperatures). low temperatures(60+100 OS)).

Thus, irrational use of fuel, when part of the heat flies out into the chimney, leads to depletion of fuel and energy resources (FER).

The gradual depletion of fuel and energy resources in the European part of our country required at one time the development of the fuel and energy complex in its eastern regions, which sharply increased the costs of fuel production and transportation. In this situation, it is necessary to solve the most important task of saving and rational use TER, because their reserves are limited and as they decrease, the cost of fuel will steadily increase.

In this regard, an effective energy-saving measure is the development and implementation of decentralized heat supply systems with dispersed autonomous heat sources.

Currently, the most appropriate are decentralized heat supply systems based on unconventional sources heat, such as sun, wind, water.

Below we will consider only two aspects of the involvement of non-traditional energy:

Heat supply based on heat pumps;

Heat supply based on autonomous water heat generators.

Heat supply based on heat pumps

The main purpose of heat pumps (HP) is heating and hot water supply using natural low-grade heat sources (LPHS) and waste heat from the industrial and domestic sectors.

The advantages of decentralized heating systems include increased reliability of heat supply, because they are not connected by heating networks, which in our country exceed 20 thousand km, and most of the pipelines are in operation beyond the standard service life (25 years), which leads to accidents. In addition, the construction of long heating mains is associated with significant capital costs and large heat losses. According to their operating principle, heat pumps are heat transformers in which a change in heat potential (temperature) occurs as a result of work supplied from outside.

The energy efficiency of heat pumps is assessed by transformation coefficients that take into account the resulting “effect” related to the work expended and efficiency.

The resulting effect is the amount of heat Qw produced by the HP. The amount of heat Qв, related to the expended power Nel on the VT drive, shows how many units of heat are obtained per unit of expended electrical power. This ratio is μ=0Β/Νelι

is called the heat conversion or transformation coefficient, which for HP is always greater than 1. Some authors call this efficiency coefficient, but the efficiency cannot be more than 100%. The mistake here is that heat Qв (as an unorganized form of energy) is divided into Nel (electric, i.e. organized energy).

Efficiency must take into account not just the amount of energy, but the performance of a given amount of energy. Consequently, efficiency is the ratio of work capacities (or exergies) of any type of energy:

where: Eq - heat efficiency (exergy) Qв; E N - efficiency (exergy) of electrical energy Neel.

Since heat is always associated with the temperature at which this heat is obtained, then the workability (exergy) of heat depends on the temperature level T and is determined by:

where τ is the heat efficiency coefficient (or “Carnot factor”):

q=(T-Tos)/T=1-Tos/

where Toc is the ambient temperature.

For each heat pump these indicators are equal:

1. Heat transformation coefficient:

μ=qв/l=Qв/Nel■

η=ΡΒ(τς)Β//=Ι*(τς)Β>

where: qв - specific amount heat, kJ/kg;

Qв - full quantity heat, kJ/s;

/ - specific cost of work, kJ/kg;

1\1EL - electrical power, kW;

(tq)B - heat efficiency coefficient =

1-Tos/TV.

For real VTs, the transformation ratio is μ=3-!-4, while η=30-40%. This means that for each kWh of electrical energy expended, QB = 3-i-4 kWh of heat is obtained. This is the main advantage of HP over other methods of generating heat (electric heating, boiler room, etc.).

Over the past few decades, the production of heat pumps has increased sharply all over the world, but in our country heat pumps have not yet found widespread use.

There are several reasons for this.

1. Traditional focus on centralized heat supply.

2. Unfavorable ratio between the cost of electricity and fuel.

3. The production of fuel pumps is carried out, as a rule, on the basis of the parameters that are closest to each other refrigeration machines, which does not always lead to optimal VT characteristics. The design of serial HPs for specific characteristics, adopted abroad, significantly increases both the operational and energy characteristics of HPs.

The production of heat pump equipment in the USA, Japan, Germany, France, England and other countries is based on the production capacities of refrigeration engineering. HPs in these countries are used mainly for heating and hot water supply in the residential, commercial and industrial sectors.

In the USA, for example, over 4 million units of heat pumps with small, up to 20 kW, heat output based on piston or rotary compressors are in operation. Heat supply to schools, shopping centers, and swimming pools is provided by heat pumps with a heating capacity of 40 kW, based on piston and screw compressors. Heat supply to districts and cities - large heat pumps based on centrifugal compressors with Qw over 400 kW of heat. In Sweden, out of 130 thousand operating HPs, more than 100 have a heating capacity of 10 MW or more. In Stockholm, 50% of the heat supply comes from HP.

In industry, heat pumps utilize low-grade heat production processes. An analysis of the possibility of using HP in industry, carried out at the enterprises of 100 Swedish companies, showed that the most suitable area For the application of TN are enterprises of the chemical, food and textile industries.

In our country, issues of using TN began to be addressed in 1926. In industry, since 1976, TNs have worked at a tea factory (Samtredia, Georgia), at the Podolsk Chemical and Metallurgical Plant (PCMP) since 1987, at the Sagarejoy Dairy Plant, Georgia, at the Gorki-2 dairy and livestock state farm near Moscow "since 1963. In addition to industry, TN at that time began to be used in a shopping center (Sukhumi) for heat and cold supply, in a residential building (Bukuria village, Moldova), in the Druzhba boarding house (Yalta), and a climatological hospital (Gagra), resort hall of Pitsunda.

In Russia, VTs are currently manufactured according to individual orders various companies in Nizhny Novgorod, Novosibirsk, Moscow. For example, the Triton company in Nizhny Novgorod produces HP with a heating capacity from 10 to 2000 kW with compressor power Nel from 3 to 620 kW.

The most common low-potential heat sources (LPHS) for HP are water and air. Hence, the most commonly used HP circuits are “water-to-air” and “air-to-air”. According to such schemes, VTs are produced by the following companies: "Cargrid", "Lennox", Westinghous", "General Electric" (USA), "Hitachi", "Daikin" (Japan), "Sulzer" (Sweden), "ČKD" (Czech Republic) , "Klimatechnik" (Germany). IN Lately Discharge industrial and sewage effluents are used as NPIT.

In countries with more severe climatic conditions, it is advisable to use HP in conjunction with traditional heat sources. At the same time, in heating season Heat supply to buildings is carried out mainly from a heat pump (80-90% of annual consumption), and peak loads (at low temperatures) are covered by electric or fossil fuel boilers.

The use of heat pumps leads to savings in fossil fuels. This is especially true for remote regions, such as the northern regions of Siberia and Primorye, where there are hydroelectric power stations and fuel transportation is difficult. With an average annual transformation coefficient m = 3-4, fuel savings from the use of HP compared to a boiler room is 30-5-40%, i.e. on average 6-5-8 kg equivalent fuel/GJ. With an increase in m to 5, fuel savings increase to approximately 20+25 kg.t./GJ compared with boiler houses using organic fuel and up to 45+65 kg.t./GJ compared with electric boilers.

Thus, HP is 1.5-5-2.5 times more profitable than boiler houses. The cost of heat from HP is approximately 1.5 times lower than the cost of heat from centralized heating supply and 2-5-3 times lower than coal and fuel oil boiler houses.

One of most important tasks is the recovery of heat from waste water from thermal power plants. The most important prerequisite for the introduction of HP is the large volumes of heat released into cooling towers. For example, the total amount of waste heat at urban and adjacent thermal power plants in the period from November to March heating season is 1600-5-2000 Gcal/h. Using HP, you can transfer most of this waste heat (about 50-5-60%) to the heating network. Wherein:

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

The environmental situation would improve;

By reducing the temperature of the circulating water in the turbine condensers, the vacuum will significantly improve and electricity generation will increase.

The scale of implementation of heat pumps only in Mosenergo OJSC can be very significant and their use on the “waste” heat of the cooling system

ren can reach 1600-5-2000 Gcal/h. Thus, the use of HP at CHP plants is beneficial not only technologically (improving vacuum), but also environmentally (real fuel savings or increasing the thermal power of CHP plants without additional fuel consumption and capital costs). All this will allow increasing the connected load in heating networks.

Fig.1. Schematic diagram of the VTG heat supply system:

1 - centrifugal pump; 2 - vortex tube; 3 - flow meter; 4 - thermometer; 5 - three-way valve; 6 - valve;

7 - battery; 8 - heater.

Heat supply based on autonomous water heat generators

Autonomous water heat generators (ATG) are designed to produce heated water, which is used to supply heat to various industrial and civil facilities.

ATG includes a centrifugal pump and a special device that creates hydraulic resistance. Special device may have different design, the efficiency of which depends on the optimization of operating factors determined by KNOW-HOW developments.

One of the special options hydraulic device is a vortex tube included in the system decentralized heat supply working on water.

The use of a decentralized heat supply system is very promising, because water, being a working substance, is used directly for heating and hot water

additional supply, thereby making these systems environmentally friendly and reliable in operation. Such a decentralized heat supply system was installed and tested in the laboratory of Fundamentals of Heat Transformation (OTT) of the Department of Industrial Heat and Power Systems (ITS) of MPEI.

The heat supply system consists of a centrifugal pump, a vortex tube and standard elements: a battery and a heater. The specified standard elements are integral parts of any heat supply systems and therefore their presence and successful work give grounds to assert reliable operation any heat supply system that includes these elements.

In Fig. Figure 1 shows a schematic diagram of the heat supply system. The system is filled with water, which, when heated, enters the battery and heater. The system is equipped with switching fittings (three-way taps and valves), which allows serial and parallel connection of the battery and air heater.

The system worked as follows. Through expansion tank the system is filled with water in such a way that air is removed from the system, which is then monitored by a pressure gauge. After this, voltage is applied to the control unit cabinet, the temperature controller sets the temperature of the water supplied to the system (50-5-90 °C), and the centrifugal pump is turned on. The time it takes to enter the mode depends on the set temperature. At a given tв=60 OS, the time to reach the mode is t=40 minutes. The temperature graph of the system operation is shown in Fig. 2.

The starting period of the system was 40+45 minutes. The rate of temperature increase was Q=1.5 degrees/min.

To measure the water temperature at the inlet and outlet of the system, thermometers 4 are installed, and a flow meter 3 is installed to determine the flow rate.

The centrifugal pump was installed on a lightweight mobile stand, the manufacture of which can be carried out in any workshop. The rest of the equipment (battery and heater) is standard, purchased from specialized trading companies (stores).

Armature ( three way valves, valves, angles, adapters, etc.) are also purchased in stores. The system is assembled from plastic pipes, welding of which was carried out with a special welding unit, which is available in the OTT laboratory.

The difference in water temperatures in the forward and return lines was approximately 2 °C (Δt=tnp-to6=1.6). The operating time of the VTG centrifugal pump was 98 s in each cycle, pauses lasted 82 s, the time of one cycle was 3 min.

The heat supply system, as tests have shown, operates stably and automatically (without the participation of maintenance personnel) maintains the initially set temperature in the range t = 60-61 °C.

The heat supply system operated with the battery and heater switched on in series with water.

The effectiveness of the system is assessed:

1. Heat transformation coefficient

μ=(Ο6+Οκ)/νν=ΣΟ/νν;

2. Efficiency

where: 20 =Q6+QK - the amount of heat given off by the system;

W is the amount of electrical energy spent on driving the centrifugal pump; tq=1-T0C/TB - heat efficiency coefficient;

TV - temperature level of heat given off; Тos - ambient temperature.

With the consumed electricity W=2 kWh, the amount of heat produced during this period was 20=3816.8 kcal. The transformation coefficient is equal to: μ=3816.8/1720=2.22.

The efficiency is η=μτ =2.22.0.115=0.255 (~25%), where: tq=1 -(293/331)=0.115.

From the energy balance of the system it is clear that the additional amount of heat generated by the system was 2096.8 kcal. Today, there are various hypotheses trying to explain how additional heat appears, but there is no clear, generally accepted solution.

conclusions

1. Decentralized heat supply systems do not require long heating pipelines, and therefore large capital costs.

2. The use of decentralized heat supply systems can significantly reduce harmful emissions from fuel combustion into the atmosphere, which improves the environmental situation.

3. The use of heat pumps in decentralized heat supply systems for industrial and civil sector facilities allows fuel savings of 6+8 kg of equivalent fuel compared to boiler houses. per 1 Gcal of generated heat, which is approximately 30-5-40%.

4. Decentralized systems based on TN are successfully used in many foreign countries(USA, Japan, Norway, Sweden, etc.). More than 30 companies are engaged in the production of fuel pumps.

5. An autonomous (decentralized) heat supply system based on a centrifugal water heat generator was installed in the OTT laboratory of the PTS department of MPEI.

The system operates in automatic mode, maintaining the water temperature in the supply line in any given range from 60 to 90 °C.

The heat transformation coefficient of the system is m=1.5-5-2, and the efficiency is about 25%.

6. Further increasing the energy efficiency of decentralized heat supply systems requires scientific and technical research to determine optimal modes work.

Literature

1. Sokolov E. Ya. et al. Cool attitude to heat. News from June 17, 1987.

2. Mikhelson V. A. O dynamic heating. Applied Physics. T.III, issue. Z-4, 1926.

3. Yantovsky E.I., Pustovalov Yu.V. Vapor compression heat pump units. - M.: Energoizdat, 1982.

4. Vezirishvili O.Sh., Meladze N.V. Energy-saving heat pump systems for heat and cold supply. - M.: MPEI Publishing House, 1994.

5. Martynov A.V., Petrakov G.N. Dual-purpose heat pump. Industrial Energy No. 12, 1994.

6. Martynov A.V., Yavorovsky Yu.V. Use of energy-reducing energy resources at chemical industry enterprises based on TNU. Chemical industry No. 4, 2000.

7. Brodyansky V.M. and others. Exergetic method and its applications. - M.: Energoizdat, 1986.

8. Sokolov E.Ya., Brodyansky V.M. Energy bases of heat transformation and cooling processes - M.: Energoizdat, 1981.

9. Martynov A.V. Installations for heat transformation and cooling. - M.: Energoatomizdat, 1989.

10. Devyanin D.N., Pishchikov S.I., Sokolov Yu.N. Heat pumps - development and testing at CHPP-28. // “Heat Supply News”, No. 1, 2000.

12. Kalinichenko A.B., Kurtik F.A. Heat generator with the most high efficiency. // “Economics and Production”, No. 12, 1998.

13. Martynov A.V., Yanov A.V., Golovko V.M. Decentralized heat supply system based on an autonomous heat generator. // " Construction Materials, equipment, technologies of the 21st century", No. 11, 2003.

From the editor: At the second scientific and practical conference “Heat supply systems. Modern solutions”, which is traditionally held by the Non-Profit Partnership “Russian Heat Supply”, after a series of reports on vortex heat generators, a heated discussion ensued. The participants came to the conclusion that the receipt of heat in an amount exceeding the consumed electricity indicates that modern science cannot yet indicate the source of this energy and its nature, which means that this phenomenon should be used with extreme caution, because the impact of this installation on environment and people have not been studied.

This is confirmed by modern research. For example, at the international conference “Anomalous physical phenomena in energy and prospects for the creation of unconventional energy sources,” held on June 15-16, 2005 in Kharkov, several groups of researchers from different cities of Ukraine reported that they had discovered radiation generated by a vortex heat generator.

For example, specialists from the Institute of Technical Thermophysics of the National Academy of Sciences of Ukraine discovered a section at the end of the vortex tube with increased (1.3-1.9 times) gamma radiation compared to the background value. Information about this experiment was also published in the journal “Industrial Heat Engineering” (Kyiv) No. 6, 2002 in the article by Khalatov A.A., Kovalenko A.S., Shevtsov S.V. “Determination of the energy conversion coefficient in a vortex heat generator type TPM 5.5-1.” The authors of the article noted that the nature of this radiation is not yet entirely clear and requires further study.

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Decentralized heating systems

Decentralized consumers, who, due to large distances from thermal power plants, cannot be covered by centralized heat supply, must have a rational (efficient) heat supply that meets the modern technical level and comfort.

The scale of fuel consumption for heat supply is very large. Currently, the heat supply to industrial, public and residential buildings is carried out approximately 40+50% from boiler houses, which is ineffective due to their low efficiency (in boiler houses the combustion temperature of fuel is approximately 1500 °C, and heat is supplied to the consumer at significantly lower temperatures (60+100 OS)).

Thus, irrational use of fuel, when part of the heat flies out into the chimney, leads to depletion of fuel and energy resources (FER).

The gradual depletion of fuel and energy resources in the European part of our country required at one time the development of the fuel and energy complex in its eastern regions, which sharply increased the costs of fuel production and transportation. In this situation, it is necessary to solve the most important problem of saving and rational use of fuel and energy resources, because their reserves are limited and as they decrease, the cost of fuel will steadily increase.

In this regard, an effective energy-saving measure is the development and implementation of decentralized heat supply systems with dispersed autonomous heat sources.

Currently, the most appropriate are decentralized heat supply systems based on non-traditional heat sources, such as sun, wind, water.

Below we will consider only two aspects of the involvement of non-traditional energy:

* heat supply based on heat pumps;

* heat supply based on autonomous water heat generators.

Heat supply based on heat pumps. The main purpose of heat pumps (HP) is heating and hot water supply using natural low-grade heat sources (LPHS) and waste heat from the industrial and domestic sectors.

The advantages of decentralized heating systems include increased reliability of heat supply, because they are not connected by heating networks, which in our country exceed 20 thousand km, and most of the pipelines are in operation beyond the standard service life (25 years), which leads to accidents. In addition, the construction of long heating mains is associated with significant capital costs and large heat losses. According to their operating principle, heat pumps are heat transformers in which a change in heat potential (temperature) occurs as a result of work supplied from outside.

The energy efficiency of heat pumps is assessed by transformation coefficients that take into account the resulting “effect” related to the work expended and efficiency.

The resulting effect is the amount of heat Qw produced by the HP. The amount of heat Qв, related to the expended power Nel on the VT drive, shows how many units of heat are obtained per unit of expended electrical power. This ratio is m=0V/Nely

is called the heat conversion or transformation coefficient, which for HP is always greater than 1. Some authors call this efficiency coefficient, but the efficiency cannot be more than 100%. The mistake here is that heat Qв (as an unorganized form of energy) is divided into Nel (electric, i.e. organized energy).

Efficiency must take into account not just the amount of energy, but the performance of a given amount of energy. Consequently, efficiency is the ratio of work capacities (or exergies) of any type of energy:

з=Еq / EN

where: Eq - heat efficiency (exergy) Qв; EN - performance (exergy) of electrical energy Nel.

Since heat is always associated with the temperature at which this heat is obtained, then the workability (exergy) of heat depends on the temperature level T and is determined by:

Eq=QBxq,

where f is the heat efficiency coefficient (or “Carnot factor”):

q=(T-Tos)/T=1-Tos/

where Toc is the ambient temperature.

For each heat pump these indicators are equal:

1. Heat transformation coefficient:

m=qв/l=Qв/Nel¦

2. Efficiency:

z=NE(ft)V//=Y*(ft)V>

For real VTs, the transformation coefficient is m = 3-!-4, while z = 30-40%. This means that for each kWh of electrical energy expended, QB = 3-i-4 kWh of heat is obtained. This is the main advantage of HP over other methods of generating heat (electric heating, boiler room, etc.).

Over the past few decades, the production of heat pumps has increased sharply all over the world, but in our country heat pumps have not yet found widespread use.

There are several reasons for this.

1. Traditional focus on centralized heat supply.

2. Unfavorable ratio between the cost of electricity and fuel.

3. The production of heat pumps 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 heat pump. The design of serial HPs for specific characteristics, adopted abroad, significantly increases both the operational and energy characteristics of HPs.

The production of heat pump equipment in the USA, Japan, Germany, France, England and other countries is based on the production capacities of refrigeration engineering. HPs in these countries are used mainly for heating and hot water supply in the residential, commercial and industrial sectors.

In the USA, for example, over 4 million units of heat pumps with small, up to 20 kW, heat output based on piston or rotary compressors are in operation. Heat supply to schools, shopping centers, and swimming pools is provided by heat pumps with a heating capacity of 40 kW, based on piston and screw compressors. Heat supply to districts and cities - large heat pumps based on centrifugal compressors with Qw over 400 kW of heat. In Sweden, out of 130 thousand operating HPs, more than 100 have a heating capacity of 10 MW or more. In Stockholm, 50% of the heat supply comes from HP.

In industry, heat pumps recover low-grade heat from production processes. An analysis of the possibility of using HP in industry, carried out at the enterprises of 100 Swedish companies, showed that the most suitable areas for using HP are enterprises in the chemical, food and textile industries.

In our country, issues of using TN began to be addressed in 1926. In industry, since 1976, TNs have worked at a tea factory (Samtredia, Georgia), at the Podolsk Chemical and Metallurgical Plant (PCMP) since 1987, at the Sagarejoy Dairy Plant, Georgia, at the Gorki-2 dairy and livestock state farm near Moscow "since 1963. In addition to industry, TN at that time began to be used in a shopping center (Sukhumi) for heat and cold supply, in a residential building (Bukuria village, Moldova), in the Druzhba boarding house (Yalta), and a climatological hospital (Gagra), resort hall of Pitsunda.

In Russia, TNs are currently manufactured to individual orders by various companies in Nizhny Novgorod, Novosibirsk, and Moscow. For example, the Triton company in Nizhny Novgorod produces HP with a heating capacity from 10 to 2000 kW with compressor power Nel from 3 to 620 kW.

The most common low-potential heat sources (LPHS) for HP are water and air. Hence, the most commonly used HP circuits are “water-to-air” and “air-to-air”. According to such schemes, VTs are produced by the following companies: "Cargrid", "Lennox", Westinghous", "General Electric" (USA), "Hitachi", "Daikin" (Japan), "Sulzer" (Sweden), "ČKD" (Czech Republic) , "Klimatechnik" (Germany). Recently, industrial and sewage wastewater has been used as NPIT.

In countries with more severe climatic conditions, it is advisable to use HP in conjunction with traditional heat sources. At the same time, during the heating season, heat supply to buildings is carried out mainly from a heat pump (80-90% of annual consumption), and peak loads (at low temperatures) are covered by electric boilers or boiler houses using organic fuel.

The use of heat pumps leads to savings in fossil fuels. This is especially true for remote regions, such as the northern regions of Siberia and Primorye, where there are hydroelectric power stations and fuel transportation is difficult. With an average annual transformation coefficient m = 3-4, fuel savings from the use of HP compared to a boiler room is 30-5-40%, i.e. on average 6-5-8 kg equivalent fuel/GJ. With an increase in m to 5, fuel savings increase to approximately 20+25 kg.t./GJ compared with boiler houses using organic fuel and up to 45+65 kg.t./GJ compared with electric boilers.

Thus, HP is 1.5-5-2.5 times more profitable than boiler houses. The cost of heat from HP is approximately 1.5 times lower than the cost of heat from centralized heating supply and 2-5-3 times lower than coal and fuel oil boiler houses.

One of the most important tasks is the recovery of heat from waste water from thermal power plants. The most important prerequisite for the introduction of HP is the large volumes of heat released into cooling towers. For example, the total amount of waste heat at urban and adjacent thermal power plants in the period from November to March of the heating season is 1600-5-2000 Gcal/h. Using HP, you can transfer most of this waste heat (about 50-5-60%) to the heating network. Wherein:

* there is no need to spend additional fuel to produce this heat;

* the environmental situation would improve;

* by reducing the temperature of the circulating water in the turbine condensers, the vacuum will significantly improve and electricity generation will increase.

The scale of implementation of heat pumps only in Mosenergo OJSC can be very significant and their use on the “waste” heat of the cooling system

ren can reach 1600-5-2000 Gcal/h. Thus, the use of HP at CHP plants is beneficial not only technologically (improving vacuum), but also environmentally (real fuel savings or increasing the thermal power of CHP plants without additional fuel consumption and capital costs). All this will allow increasing the connected load in heating networks.

Fig.1. Schematic diagram of the VTG heat supply system:

1 - centrifugal pump; 2 - vortex tube; 3 - flow meter; 4 - thermometer; 5 - three-way valve; 6 - valve; 7 - battery; 8 - heater.

Heat supply based on autonomous water heat generators. Autonomous water heat generators (ATG) are designed to produce heated water, which is used to supply heat to various industrial and civil facilities.

ATG includes a centrifugal pump and a special device that creates hydraulic resistance. A special device can have a different design, the efficiency of which depends on the optimization of operating factors determined by KNOW-HOW developments.

One option for a special hydraulic device is a vortex tube, included in a decentralized heat supply system operating on water.

The use of a decentralized heat supply system is very promising, because water, being a working substance, is used directly for heating and hot water

additional supply, thereby making these systems environmentally friendly and reliable in operation. Such a decentralized heat supply system was installed and tested in the laboratory of Fundamentals of Heat Transformation (OTT) of the Department of Industrial Heat and Power Systems (ITS) of MPEI.

The heat supply system consists of a centrifugal pump, a vortex tube and standard elements: a battery and a heater. The specified standard elements are integral parts of any heat supply systems and therefore their presence and successful operation give grounds to assert the reliable operation of any heat supply system that includes these elements.

In Fig. Figure 1 shows a schematic diagram of the heat supply system. The system is filled with water, which, when heated, enters the battery and heater. The system is equipped with switching fittings (three-way taps and valves), which allows serial and parallel connection of the battery and air heater.

The system worked as follows. Through the expansion tank, the system is filled with water so that air is removed from the system, which is then monitored by a pressure gauge. After this, voltage is applied to the control unit cabinet, the temperature controller sets the temperature of the water supplied to the system (50-5-90 °C), and the centrifugal pump is turned on. The time it takes to enter the mode depends on the set temperature. At a given tв=60 OS, the time to reach the mode is t=40 minutes. The temperature graph of the system operation is shown in Fig. 2.

The starting period of the system was 40+45 minutes. The rate of temperature increase was Q=1.5 degrees/min.

To measure the water temperature at the inlet and outlet of the system, thermometers 4 are installed, and a flow meter 3 is installed to determine the flow rate.

The centrifugal pump was installed on a lightweight mobile stand, the manufacture of which can be carried out in any workshop. The rest of the equipment (battery and heater) is standard, purchased from specialized trading companies (stores).

Fittings (three-way taps, valves, angles, adapters, etc.) are also purchased in stores. The system is assembled from plastic pipes, welding of which was carried out with a special welding unit, which is available in the OTT laboratory.

The difference in water temperatures in the forward and return lines was approximately 2 °C (Dt=tnp-to6=1.6). The operating time of the VTG centrifugal pump was 98 s in each cycle, pauses lasted 82 s, the time of one cycle was 3 min.

The heat supply system, as tests have shown, operates stably and automatically (without the participation of maintenance personnel) maintains the initially set temperature in the range t = 60-61 °C.

The heat supply system operated with the battery and heater switched on in series with water.

The effectiveness of the system is assessed:

1. Heat transformation coefficient

m=(P6+Pk)/nn=UP/nn;

From the energy balance of the system it is clear that the additional amount of heat generated by the system was 2096.8 kcal. Today, there are various hypotheses trying to explain how additional heat appears, but there is no clear, generally accepted solution.

conclusions

decentralized heat supply unconventional energy

1. Decentralized heat supply systems do not require long heating pipelines, and therefore large capital costs.

2. The use of decentralized heat supply systems can significantly reduce harmful emissions from fuel combustion into the atmosphere, which improves the environmental situation.

3. The use of heat pumps in decentralized heat supply systems for industrial and civil sector facilities allows fuel savings of 6+8 kg of equivalent fuel compared to boiler houses. per 1 Gcal of generated heat, which is approximately 30-5-40%.

4. Decentralized systems based on TN are successfully used in many foreign countries (USA, Japan, Norway, Sweden, etc.). More than 30 companies are engaged in the production of fuel pumps.

5. An autonomous (decentralized) heat supply system based on a centrifugal water heat generator was installed in the OTT laboratory of the PTS department of MPEI.

The system operates in automatic mode, maintaining the water temperature in the supply line in any given range from 60 to 90 °C.

The heat transformation coefficient of the system is m=1.5-5-2, and the efficiency is about 25%.

6. Further increasing the energy efficiency of decentralized heat supply systems requires scientific and technical research to determine optimal operating modes.

Literature

1. Sokolov E. Ya. et al. Cool attitude to heat. News from June 17, 1987.

2. Mikhelson V. A. About dynamic heating. Applied Physics. T.III, issue. Z-4, 1926.

3. Yantovsky E.I., Pustovalov Yu.V. Vapor compression heat pump units. - M.: Energoizdat, 1982.

4. Vezirishvili O.Sh., Meladze N.V. Energy-saving heat pump systems for heat and cold supply. - M.: MPEI Publishing House, 1994.

5. Martynov A.V., Petrakov G.N. Dual-purpose heat pump. Industrial Energy No. 12, 1994.

6. Martynov A.V., Yavorovsky Yu.V. Use of energy-reducing energy resources at chemical industry enterprises based on TNU. Chemical industry

7. Brodyansky V.M. and others. Exergetic method and its applications. - M.: Energoizdat, 1986.

8. Sokolov E.Ya., Brodyansky V.M. Energy bases of heat transformation and cooling processes - M.: Energoizdat, 1981.

9. Martynov A.V. Installations for heat transformation and cooling. - M.: Energoatomizdat, 1989.

10. Devyanin D.N., Pishchikov S.I., Sokolov Yu.N. Heat pumps - development and testing at CHPP-28. // “Heat Supply News”, No. 1, 2000.

11. Martynov A.V., Brodyansky V.M. “What is a vortex tube?” M.: Energy, 1976.

12. Kalinichenko A.B., Kurtik F.A. Heat generator with the highest efficiency. // “Economics and Production”, No. 12, 1998.

13. Martynov A.V., Yanov A.V., Golovko V.M. Decentralized heat supply system based on an autonomous heat generator. // “Building materials, equipment, technologies of the 21st century”, No. 11, 2003.

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Sanitary and technical installations of buildings included in the local heat supply system. Such devices include autonomous boiler houses and heat generators with thermal power from 3-20 kW to 3000 kW (including rooftop and block-mobile ones), and individual apartment heat generators. This equipment is intended for heat supply to a separate facility (sometimes a small group of nearby facilities) or an individual apartment or cottage.

Features of the design and construction of autonomous boiler houses for various types civil objects are regulated by a set of rules SP 41-104-2000 “Design autonomous sources heat supply."

Based on their location in space, autonomous boiler houses are divided into free-standing, attached to buildings for other purposes, built into buildings for other purposes, regardless of the floor of location, and roof-mounted. The thermal power of the built-in, attached and roof boiler room should not exceed the heat requirement of the building for which it is intended to supply heat. But the general thermal power an autonomous boiler house should not exceed: 3.0 MW for a roof-mounted and built-in boiler house with liquid and gaseous fuel boilers; 1.5 MW for a built-in boiler room with solid fuel boilers.

It is not allowed to design roof-mounted, built-in and attached boiler houses to the buildings of children's preschool and school institutions, to the medical buildings of hospitals and clinics with round-the-clock stay of patients, to the dormitory buildings of sanatoriums and recreational institutions.

The possibility of installing a roof boiler room on buildings of any purpose above the level of 26.5 m must be agreed with the local authorities of the State Fire Service.

The scheme with autonomous heat supply sources works as follows. The water heated in the boiler (primary circuit) enters the heaters, where it heats the water secondary circuit, entering the heating, ventilation, air conditioning and domestic hot water systems, and returns to the boiler. In this scheme, the water circulation circuit in the boilers is hydraulically isolated from the circulation circuits of subscriber systems, which makes it possible to protect the boilers from replenishing them poor quality water in the presence of leaks, and in some cases, abandon water treatment altogether and ensure reliable scale-free boiler operation.

Repair areas are not provided for in autonomous and rooftop boiler houses. Repair of equipment, fittings, control and regulation devices is carried out by specialized organizations that have the appropriate licenses, using their lifting devices and bases.

The equipment of autonomous boiler rooms must be located in a separate room, inaccessible to unauthorized entry. For built-in and attached autonomous boiler houses, closed warehouses for storing solid or liquid fuel are provided, located outside the boiler room and the building for which it is intended to supply heat.

Equipment for autonomous heat supply sources, which include cast iron steel boilers, small-sized steel and cast iron sectional boilers, small-sized modular boilers, horizontal sectional shell-and-tube and plate water heaters, steam-water and capacitive heaters. Currently, the domestic industry produces cast iron and steel boilers designed for burning gas, liquid boiler and furnace fuel, for layer combustion of sorted solid fuel on grates and in a suspended (vortex, fluidized) state. If necessary solid fuel boilers can be converted to burn gaseous and liquid fuels by installing appropriate gas burner devices or nozzles and automation for them on the front plate.

Of the small-sized cast-iron sectional boilers, the most widely used are KChM brand boilers of various modifications.

Small-sized steel boilers are produced by many machine-building enterprises of various departments, mainly as consumer goods. They are less durable than cast iron boilers(the service life of cast iron boilers is up to 20 years, steel 8-10 years), but they are less metal-intensive and not so labor-intensive to manufacture and are somewhat cheaper on the boiler and equipment market.

All-welded steel boilers are more gas-tight than cast iron boilers. Thanks to smooth surface their pollution from the gas side during operation is less than that of cast iron boilers, they are easier to repair and maintain. The efficiency (efficiency) of steel boilers is close to that of cast iron boilers.

In addition to domestic boilers, many boilers from foreign companies have appeared on the market of boilers and boiler auxiliary equipment in recent years, including: PROTHERM (Slovakia), Buderus (an enterprise part of the Bosch group of companies, Germany), Vapor Finland Oy ( Finland). These companies produce boiler equipment power from 10 kW to 1 MW for industrial enterprises, warehouses, private houses, cottages, small industries. They are all different high quality execution, good automation and control devices, excellent design. But their retail prices, with the same thermal characteristics, are 3-5 times higher than the prices for Russian equipment, so they are less accessible to the mass buyer.

Water-water horizontal sectional shell-and-tube and plate water heaters (figure below), used in boiler houses, are switched on according to countercurrent coolant flow patterns.

Design of water heaters: water-water sectional (a) and plate (b) water heaters

1 - inlet pipe; 2 - tube sheets; 3 - tubes; 4 - body; 5 - package; 6 - bolts; 7 - plates

Steam-water and capacitive heaters are used in steam boiler houses. They are equipped with safety valves on the side of the heated medium, as well as air and drain devices. Each steam-water heater must be equipped with a condensate drain or overflow regulator to drain condensate, fittings with shut-off valves for releasing air and draining water, and a safety valve provided in accordance with the requirements of PB 10-115-96 of the Gosgortekhnadzor of Russia.

In boiler houses, it is recommended to use foundationless pumps, the flow and pressure of which are determined by thermal-hydraulic calculations. The number of pumps in the primary circuit of the boiler room should be at least two, one of which is a backup one. The use of twin pumps is allowed.

Autonomous heat supply sources have small dimensions, therefore the number of shut-off and control valves on pipelines should be the minimum necessary to ensure reliable and trouble-free operation. Installation sites for shut-off and control valves must be equipped with artificial lighting.

Expansion tanks must be equipped with safety valves, and one sump filter (or ferromagnetic filter) must be installed on the supply pipeline at the inlet (directly after the first valve) and on the return pipeline in front of control devices, pumps, water and heat metering devices ).

In autonomous boiler houses operating on liquid and gaseous fuels, it is necessary to provide easily removable (in the event of an explosion) enclosing structures at the rate of 0.03 m 2 per 1 m 3 of the volume of the room in which the boilers are located.

Apartment-by-apartment heat supply - providing heat to heating, ventilation and hot water supply systems for apartments in a residential building. The system consists of an individual heat source - a heat generator, hot water supply pipelines with water fittings, heating pipelines with heating devices and heat exchangers for ventilation systems.

Individual heat generators - automated boilers of full factory readiness various types top-liva, including on natural gas operating without permanent staff.

Heat generators with a closed (sealed) combustion chamber should be used for multi-apartment residential buildings and built-in public premises (coolant temperature up to 95 °C, coolant pressure up to 1.0 MPa). They are equipped with an automatic safety system that ensures that the fuel supply is stopped in the event of a power outage, a malfunction of the protection circuits, the burner flame goes out, the coolant pressure drops below the maximum permissible, or the maximum permissible temperature is reached. permissible temperature coolant, smoke removal failure.

Heat generators with an open combustion chamber for hot water supply systems are used in apartments of residential buildings up to 5 floors high.

Heat generators with a total heating capacity of up to 35 kW can be installed in kitchens, corridors, in non-residential premises of apartments, and in built-in public premises - in rooms without permanent occupancy. Heat generators with a total heat output of over 35 kW (but up to 100 kW) should be placed in a specially designated room.

The intake of air necessary for fuel combustion must be carried out: for heat generators with closed cameras combustion by air ducts outside the building; for heat generators with open cameras combustion - from the premises in which they are installed.

When placing a heat generator in public premises, it is necessary to install a gas control system with automatic shutdown of the gas supply to the heat generator when a dangerous gas concentration in the air is reached - over 10% of the lower concentration limit of natural gas flame propagation.

Maintenance and repair of heat generators, gas pipelines, chimneys and air ducts for intake of outside air are carried out by specialized organizations that have their own emergency dispatch service.

Slide 2

Centralized heating system

Slide 3

Centralized heat supply is characterized by the presence of an extensive branched subscriber heating network with power supply to numerous heat receivers (factories, enterprises, buildings, apartments, residential premises, etc.)

The main sources for centralized heat supply are: combined heat and power plants (CHP), which also simultaneously generate electricity; boiler houses (hot water and steam).

Slide 4

District heating structure

Central system heating system includes several elements: A source of heat carrier. This is a thermal power plant that produces heat and electricity. Source of heat transportation – heating network. Source of heat consumption. These are heating devices located in homes, offices, warehouses and other premises of various types.

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Heating system diagrams

Dependent heating system circuit – the central heating system is designed to operate on superheated water. Its cost is lower than the cost of an independent circuit, due to the exclusion of elements such as heat exchangers, an expansion tank and a make-up pump, the functions of which are performed centrally at the thermal station. Superheated water from the main external heating network is mixed with return water(t=70-750С) intra-house system heating and, as a result, water of the required temperature is supplied to the heating devices. With this connection, in-house heating points are usually equipped with mixing units (elevators). The disadvantage of a dependent connection scheme with mixing is that the system is not protected from an increase in hydrostatic pressure, directly transmitted through the return heat pipe, to a value dangerous for the integrity of heating devices and fittings.

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Independent heating system circuit (heat exchanger) - superheated water from the boiler is supplied to the heat exchanger. A heat exchanger (water heater) is a device in which heating cold water to the required temperature and intended for heating the building, occurs due to the superheated water of the boiler room. An independent connection scheme is used when an increase in hydrostatic pressure in the system is not allowed. The advantage of an independent scheme, in addition to providing a thermal-hydraulic regime individual for each building, is the ability to maintain circulation using the heat content of water for some time, usually sufficient to eliminate emergency damage external heat pipes. A heating system with an independent circuit lasts longer than a system with a local boiler house, due to the reduction in the corrosive activity of water.

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Types of connections:

Single pipe heating systems apartment buildings due to their economy, they have many disadvantages, and the main one is the large heat loss along the route. That is, water in such a circuit is supplied from the bottom up, entering the radiators in each apartment and giving off heat, because the water cooled in the device returns to the same pipe. The coolant reaches the final destination having already cooled down considerably.

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Connection diagram for radiators of a single-pipe heating system

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A two-pipe heating system in an apartment building can be open or closed, but it allows you to keep the coolant at a certain temperature for radiators of any level. In a two-pipe heating circuit, the cooled water from the radiator no longer returns to the same pipe, but is discharged into the return channel or “return”. Moreover, it does not matter at all whether the radiator is connected from a riser or from a sun lounger - the main thing is that the temperature of the coolant remains unchanged along the entire path along the supply pipe. An important advantage in a two-pipe circuit is the fact that you can regulate each battery separately and even install taps with a thermostat on it to automatically maintain temperature regime. Also in such a circuit you can use devices with side and bottom connections, use dead-end and parallel movement of the coolant.

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Connection diagram for radiators of a two-pipe heating system

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Advantages of centralized heating:

removal of explosive technological equipment from residential buildings; point concentration of harmful emissions at sources where they can be effectively combated; The ability to use cheap fuel, work on different types of fuel, including local, garbage, as well as renewable energy resources; the ability to replace simple fuel combustion (at a temperature of 1500-2000 °C to heat the air to 20 °C) with thermal waste from production cycles, primarily thermal cycle electricity production at thermal power plants; relatively much higher electrical efficiency large thermal power plants and thermal efficiency of large boiler houses operating on solid fuel. Easy to use. You do not need to monitor the equipment - central heating radiators always produce a stable temperature (regardless of weather conditions

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Disadvantages of centralized heating:

A huge number of heat consumers who have their own heat supply mode, which almost completely eliminates the possibility of regulating heat supply; Unit cost of the district heating system, which in turn depends on the load density. Overestimation of heat costs in some cities; Complex, expensive, bureaucratic procedure for connecting to central heating; Lack of ability to regulate consumption volumes; The inability of residents to independently regulate the heating on and off; Long term summer blackouts DHW. Heating networks in most cities are worn out, and heat losses in them exceed standard values.

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Decentralized heating system

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A heat supply system is called decentralized if the heat source and heat sink are practically combined, that is, the heat network is either very small or absent.

Such heat supply can be individual, when separate heating devices are used in each room. Decentralized heating differs from centralized heating in the local distribution of the heat produced

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Main types of decentralized heating

Electric Direct Accumulation Heat pump Furnace Small boiler houses

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Oven Small Boiler House

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Types of systems involving non-traditional energy:

heat supply based on heat pumps; heat supply based on autonomous water heat generators.

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HEAT PUMPS FOR HEATING can be placed

In borehole collectors that are installed vertically into the ground to a depth of up to 100 m In underground horizontal collectors

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Operating principle

Thermal energy enters the heat exchanger, heating the coolant (water) of the heating system. Giving off heat, the refrigerant cools down and, with the help of an expansion valve, is again converted into a liquid state. The cycle is completed. To “extract” heat from the ground, a refrigerant is used - a gas with a low boiling point. The liquid refrigerant flows through a system of pipes buried in the ground. The temperature of the earth at a depth of more than 1.5 meters is the same in summer and winter and is equal to 8 degrees. This temperature is enough for the refrigerant passing through the ground to “boil” and turn into a gaseous state. This gas is sucked into the compressor pump, at which point it is compressed and heat is released. The same thing happens when you inflate a tire with a bicycle pump - the sudden compression of the air causes the pump to become warm.

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Autonomous water heat generators

Fuel-free heat generators are based on the principle of cavitation. In this case, electricity is needed to operate the pump motor, and scale does not form at all. Cavitation processes in the coolant arise as a result mechanical impact on liquid in a closed volume, which inevitably leads to its heating. Modern installations have a cavitator in the circuit, i.e. The liquid is heated through repeated circulation along the “pump – cavitator – container (radiator) – pump” circuit. By including a cavitator in the installation scheme, it is possible to increase the service life of the pump due to the transfer of cavitation processes from working chamber pump into the cavity of the cavitator. In addition, this unit is the main source of heating, since it is in it that the kinetic energy of a moving fluid is converted into thermal energy.

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Main pump Cavitator Circulation pump Solenoid valve Valve Expansion tank Heating radiator

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Other energy saving technologies

Customized systems heating Convector heating (gas air heaters, including a burner, heat exchanger and fan) Gas-radiant heating (“light” and “dark” infrared heaters)

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The most common autonomous (decentralized) heat supply scheme includes: single-circuit or double-circuit boiler, circulation pumps for heating and hot water supply, check valves, closed expansion tanks, safety valves. With a single-circuit boiler, a capacitive or plate heat exchanger is used to prepare hot water.

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Apartment heating

Apartment heating - decentralized (autonomous) individual provision separate apartment in an apartment building with heat and hot water

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Double-circuit wall-mounted boilers provide, along with heating, the preparation of hot water for domestic needs. Thanks to its small dimensions, not much larger than the size of a regular gas water heater, it is not difficult to find a place for the boiler in any room, even not specially adapted for a boiler room: in the kitchen, in the corridor, hallway, etc. Individual heating systems make it possible to completely solve the problem of saving gas fuel, while each resident, using the possibilities installed equipment, creates for himself comfortable conditions accommodation. System implementation apartment heating immediately eliminates the problem of heat accounting: not heat is taken into account, but only gas consumption. The cost of gas reflects the components of heat and hot water.

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Air heating and ventilation

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Gas-radiant heating

To organize radiant heating, infrared emitters are placed in the upper part of the room (under the ceiling), heated from the inside by gas combustion products. When using SGLO, heat is transferred from the emitters directly to the working area by thermal infrared radiation. Like sun rays, it almost entirely reaches working area, heating personnel, the surface of workplaces, floors, walls. And from these warm surfaces the air in the room is heated. The main result of radiant infrared heating is the possibility of significantly reducing the average indoor air temperature without deteriorating working conditions. The average room temperature can be reduced by 7°C, providing savings of up to 45% compared to traditional convection systems.

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Advantages of a decentralized heating system:

reduction of heat losses due to the lack of external heating networks, minimizing losses of network water, reducing costs for water treatment; no need for land allocations for heating networks and boiler houses; full automation, including heat consumption modes (no need to control the temperature of the return network water, the heat output of the source, etc.); flexibility in controlling the set temperature directly in the work area; direct heating costs and operating costs for maintaining the system are lower; efficiency in heat consumption.

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Disadvantages of a decentralized heat supply system:

User negligence. Any system requires periodic preventive inspection and maintenance Problem of smoke removal. The need to create a high-quality ventilation system and the negative impact on the environment. Reduced system efficiency due to unheated neighboring rooms. At apartment heating in a multi-storey building, an organizational and technical solution to the heating issue is necessary stairwells and other public places, lack of a clear owner, because the boiler room is the collective property of the residents; No depreciation and long term raising funds for necessary major repairs; Lack of a system for rapid supply of spare parts.