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Introduction

Heat losses are an individual characteristic of each heating network and must be determined for each network individually. Transporting heat from the heat source to consumers in systems district heating associated with losses of thermal energy, which are explained by cooling of the surface of pipelines upon contact with environment, with coolant leaks, with the operation of pumps for pumping coolant, as well as with non-optimal thermal and hydraulic operating conditions of the networks. In various speeches and publications, the amount of heat losses during transportation in existing heating networks is estimated at 15-20% of the thermal energy supplied from sources. Heat losses are included in tariffs for thermal energy and are one of the indicators of energy efficiency of operation of heating networks, therefore determining the actual value of these losses is an important practical task.

Energy losses in heating networks are inextricably linked with the loss of resources. In case of leaks, coolants are irretrievably lost, which must be replenished at the heat source. The preparation of the coolant costs: material resources, and so is energy.

Other lost resources are pipeline material, their thermal and waterproofing, which fail due to corrosion, moisture and mechanical damage. In this case, the manufacture and installation of new pipelines or the restoration of insulating structures require significant material, labor and energy costs.

Climatic conditions in Russia predetermine heat supply as the most socially significant and at the same time the most fuel-intensive sector of the economy, which consumes approximately 40% of the energy resources used in the country, with about half of these resources coming from the household sector. According to data, about 72% of thermal energy is produced by centralized heat sources (with a capacity of more than 20 MW), the remaining 28% is produced by decentralized sources, including 18% by autonomous and individual heat sources. At the same time, a small part of thermal energy is provided by recycling waste heat from process plants and using renewable energy sources. At present, the state of heat supply cannot be considered satisfactory. Many centralized heat sources have exhausted their resources. About 50% of municipal heat supply facilities and utility networks require replacement, at least 15% are in disrepair. For every 100 km of heating networks, an average of 70 damages are recorded annually. 82% of the total length of heating networks require major repairs or replacement.

The purpose of the study of this work is to calculate the efficiency of thermal insulation and thermal energy savings when restoring damaged heat pipeline insulation using the example of the heating network in the city of Shatura.

Research objectives:

1. Study of regulatory documents;

2. Analysis and synthesis of the studied materials;

3. Calculation of the effectiveness of thermal insulation.

4. Comparison of heat loss by uninsulated heat pipes with a heat network with pre-insulated pipes.

1. Systems for transportation and distribution of thermal energy

Transportation of thermal energy takes place in almost every industry and in the housing and communal services complex.

Heat is transferred from a source to consumers using heat supply systems, which include a source, a heating network and consumers. Heat supply system is a set of technical devices, units and subsystems that ensure the preparation of coolant, its transportation and distribution in accordance with the demand for heat among individual consumers for heating, ventilation, hot water supply and process heat supply.

Depending on the location of the heat source in relation to consumers, heat supply systems are divided into decentralized and centralized.

In decentralized systems, the heat source and heat receivers of consumers are either combined in one unit or placed so close that the transfer of heat from the source to the heat receivers can be carried out practically without an intermediate link - a heating network.

Systems decentralized heat supply are divided into individual and local.

IN individual systems Heat supply for each room (workshop area, room, apartment) is provided from a separate source. Such systems, in particular, include stove and apartment heating. In local systems, heat supply to each building is provided from a separate heat source, usually from a local or individual boiler house. This system, in particular, includes the so-called central heating buildings.

A set of installations designed for the preparation, transportation and use of coolant constitutes a centralized heat supply system. In centralized heat supply systems, the heat source and heat receivers of consumers are located separately, often at a considerable distance, so heat from the source to consumers is transferred through heating networks.

Depending on the degree of centralization, district heating systems can be divided into the following four groups:

§ group - heat supply from one source to a group of buildings;

§ district - heat supply from one source to several groups of buildings (district);

§ urban - heat supply from one source to several areas;

§ intercity - heat supply from one source to several cities.

Depending on the phase state of the coolant, heating networks are divided into water and steam. Water networks are used to supply heat to buildings and to cover low-potential industrial process loads. Steam networks are also used to provide high-potential industrial process loads.

The practice of heat supply has shown a number of advantages of water as a coolant compared to steam, namely:

The ability to transport heat over long distances without large losses of temperature potential, and, therefore, the possibility of more economical combined heat and electricity generation at thermal power plants;

Convenience of central qualitative and quantitative regulation of heat supply at its source;

Ease of connection of most subscriber systems to heating networks;

Preservation of all heating steam condensate at thermal power plants in water heating units.

Steam, in turn, has the following advantages over water: heat supply insulation thermal

Wider possibilities for use as a coolant (greater versatility);

Low density and insignificance of hydrostatic pressures created in pipelines even with the most unfavorable terrain in heat-supply areas;

Ease of detection and elimination of accidents in networks, since steam always comes to the surface of the earth, and welding work in case of accidents can be carried out immediately after turning off the steam;

No electricity consumption for steam transmission, since it is supplied to the subscriber under pressure in steam generators at the heat source, and energy consumption for condensate return is very insignificant compared to energy consumption for pumping water in water heating networks.

2. Heat losses in heating networks

According to summary data on heat supply facilities in 89 regions of the Russian Federation, the total length of heating networks in two-pipe terms is about 183,300 km. The average wear process is estimated at 60-70%.

The main indicators of energy efficiency of heating networks are the values ​​given below.

Specific consumption of network water per unit of connected heat load.

Specific consumption of electrical energy for coolant transport.

The difference in temperature of the network water in the supply and return pipelines or the temperature of the network water in return pipeline subject to the temperature of the network water in the supply pipeline according to the temperature schedule.

Loss of thermal energy through heat transport, through insulation and through leakage of network water.

Loss of network water.

These indicators must be established by the heating network design, entered into the heating network passport and checked during an energy survey.

Below, in Table 1, are the results of calculations of the annual standard and excess losses of thermal energy and fuel at average coolant-water temperatures in the supply and return pipelines during heating season 90 and 50C, respectively.

Table 1

Below, in Table 2, are the results of calculations of the costs of electricity, fuel and funds for pumping coolant at sources and in heating networks.

Table 2

Heat losses in main and distribution networks are significantly different. The technical condition of backbone networks is, as a rule, much better. In addition, the total surface of the main networks through which thermal energy is lost is significantly less than the surface of much more branched and extended networks. distribution networks. Therefore, trunk networks account for a several times smaller share of heat losses compared to distribution networks.

3. Measures to reduce heat losses

Progressive technologies.

Progressive technologies make it possible to increase the durability of heating networks, increase their reliability and at the same time increase the efficiency of heat transport.

Below is brief description such technologies.

1) Channelless installation of heat pipes of the “pipe-in-pipe” type with polyurethane foam insulation in a polyethylene shell and an insulation moisture control system.

Such heat pipelines make it possible to eliminate by 80% the possibility of damage to pipelines from external corrosion, reduce heat loss through insulation by 2-3 times, reduce operating costs for maintaining heating mains, reduce construction time by 2-3 times, reduce capital costs by 1.2 times laying heating mains compared to channel laying. Polyurethane foam insulation is designed for long-term exposure to coolant temperatures up to 130°C and short-term peak exposure to temperatures up to 150°C. Prerequisite reliable and trouble-free operation of pipelines of heating networks - the presence of a system of operational-remote monitoring (ODC) of insulation. This system allows you to control the quality of installation and welding of a steel pipeline, factory insulation, and work on insulating butt joints. The system includes: signal copper conductors embedded in all elements of the heating network; terminals along the route and at control points (central heating station, boiler room); monitoring devices: portable for periodic and stationary for continuous monitoring. The system is based on measuring the conductivity of the thermal insulation layer, which changes with changes in humidity. Monitoring the condition of the UEC during pipeline operation is carried out using a detector. One detector allows you to simultaneously monitor two pipes up to 5 km each. The exact location of the damaged area is determined using a portable locator. One locator allows you to determine the location of a fault at a distance of up to 2 km from its connection point. The service life of heating networks with polyurethane foam insulation is predicted to be 30 years.

2) Bellows expansion joints, unlike stuffing box expansion joints, provide complete tightness compensation devices, reduce operating costs. Reliable bellows expansion joints are produced by Metalkomp JSC for all pipeline diameters for channelless, channel, ground and above-ground installations. The use of bellows expansion joints at Mosenergo JSC, installed on main pipelines with a diameter of 300 to 1400 mm in an amount of more than 2000 pieces, made it possible to reduce specific water leaks from 3.52 l/m 3 h in 1994 to 2.43 l/m 3 hours in 1999

3) High-density ball valves, hydraulically driven ball valves, used as cut-off valves, can improve the performance characteristics of the valves and radically change existing schemes protection of heating systems from pressure increase.

4) The introduction of new schemes for regulating the performance of pumping stations using variable frequency drives, the use of protection schemes against an increase in pressure in the return line when the pumping station is stopped can significantly improve the reliability of equipment operation and reduce energy consumption during the operation of these stations.

5) Ventilation of channels and chambers is aimed at reducing heat losses through insulation of heat pipes, which is one of most important tasks operation of heating networks. One of the reasons for increased heat loss through the insulation of an underground heat pipeline is its moisture. To reduce humidity and reduce heat losses, it is necessary to ventilate channels and chambers, which allows you to maintain the moisture state of thermal insulation at a level that ensures minimal heat losses.

6) About a third of damage to heating networks is caused by internal corrosion processes. Even compliance with the standard value of leaks in heating networks, equal to 0.25% of the volume of all pipelines, which is 30,000 t/h, leads to the need for strict control of the quality of make-up water.

The main parameter that can be influenced is the pH value.

Increasing the pH value of supply water is a reliable way to combat internal corrosion, provided that the normal oxygen content in the water is maintained. The high degree of protection of pipelines at pH 9.25 is determined by changes in the properties of iron oxide films.

The level of pH increase that provides reliable protection pipelines from internal corrosion, significantly depends on the content of sulfates and chlorides in the network water.

The greater the concentration of sulfates and chlorides in water, the higher the pH value should be.

One of the few ways to extend the working life of heating networks laid in a standard way, excluding pipelines in polyurethane foam insulation, is anti-corrosion coatings.

Thermal insulation of pipelines and heating network equipment is used for all types of installation, regardless of the temperature of the coolant. Thermal insulation materials are in direct contact with the external environment, which is characterized by continuous fluctuations in temperature, humidity and pressure. In view of this, thermal insulation materials and structures must satisfy a number of requirements. Considerations of efficiency and durability require that the choice of thermal insulation materials and design be made taking into account the installation methods and operating conditions determined by the external load on the thermal insulation, groundwater level, coolant temperature, and the hydraulic operating mode of the heating network.

New types of thermal insulation coatings should have not only low thermal conductivity, but also low air and water permeability, as well as low electrical conductivity, which reduces electrochemical corrosion of the pipe material.

The most economical type of laying heat pipelines for heating networks is above-ground laying. However, taking into account architectural and planning requirements, environmental requirements in populated areas, the main type of installation is underground installation in through, semi-through and non-through channels. Ductless heat pipelines, being more economical in comparison with channel laying in terms of capital costs for their construction, are used in cases where they thermal efficiency and durability are not inferior to heat pipes in non-passing channels.

Thermal insulation is provided for linear sections of heating network pipelines, fittings, flange connections, compensators and pipe supports for above-ground, underground channel and non-channel installation.

Heat losses from the surface of pipelines increase when the thermal insulation is moistened. Moisture reaches the surface of pipelines when they are flooded with ground and surface water. Other sources of moisture in thermal insulation are natural moisture contained in the soil. If pipelines are laid in channels, then moisture from the air may condense on the surface of the channel ceilings and fall in the form of drops onto the surface of the pipelines. To reduce the impact of droplets on thermal insulation, ventilation of heating network channels is necessary. Moreover, moistening the thermal insulation contributes to the destruction of pipes due to corrosion of their outer surface, which leads to a reduction in the service life of pipelines. Therefore on metal surface pipes are coated with anti-corrosion coatings.

Thus, the main energy-saving measures that reduce heat loss from the surface of pipelines are:

§ Insulation of uninsulated areas and restoration of the integrity of existing thermal insulation;

§ restoration of the integrity of the existing waterproofing;

§ application of coatings consisting of new thermal insulation materials, or the use of pipelines with new types of thermal insulation coatings;

§ insulation of flanges and shut-off valves.

Insulation of non-insulated areas is a primary energy-saving measure, since heat losses from the surface of non-insulated pipelines are very large compared to losses from the surface of insulated pipelines, and the cost of applying thermal insulation is relatively low.

Let's compare heat losses by uninsulated heat pipes with a heat network with pre-insulated pipes using the example of the heat supply system of the city of Shatura.

4. Calculation of the effectiveness of thermal insulation.

Characteristics of the heat supply system in Shatura.

Heat supply for residential, administrative and industrial buildings The city of Shatura is carried out from the heating plant GRES-5. The heating network is fed with deaerated, chemically purified water.

The pressure in the return line is maintained by the make-up regulator.

From GRES-5, heat supply to all heat consumers is carried out through two-pipe water heating networks.

The mains are laid in transitional reinforced concrete channels with prefabricated reinforced concrete covering. The branches are laid in brick and reinforced concrete channels covered with reinforced concrete slabs. As thermal insulation, diatomaceous earth brick was used, covered with asbestos-cement plaster on top, and with aluminum sheets on the head sections.

The distribution and quarterly networks are partially insulated with suspended mineral wool, plastered with asbestos cement.

The main part of the highway is brought to the surface.

Part of the highway is laid on high and low supports. There are jumpers between the mains that allow for parallel heat supply to urban consumers, and in case of emergency situations allows for interchangeability.

Compensation for temperature expansions is carried out mainly U-shaped expansion joints and by changing the direction of the heating main.

Heating system of the group under consideration residential buildings connect to water networks via dependent circuit. Water is used as a coolant in heating systems.

Thermal regime of the heating system.

For the city's heat supply system, a method has been adopted for qualitative regulation of heat supply, which provides for a constant flow of coolant in heating systems at a variable temperature, depending on the outside air temperature.

Regulation of the city's heat supply is carried out according to a temperature schedule of 150-70 C.

Thermal insulation efficiency.

Average annual temperature of network water in the supply pipeline:

S, reverse S.

Laying of the pipeline above ground (in channels).

Diameter of heat pipes m. Diameter of insulation m.

Insulation - pierced mineral wool mats, 0.07 m thick. Covering layer of brizol in 2 layers.

Thermal conductivity coefficient of the main insulation layer.

Where for the supply pipe

For return pipe:

Thermal resistance of the main insulation layer for each pipe:

Thermal resistance of the covering layer for each pipe:

Where is the thermal conductivity coefficient of the brizol cover layer.

Thermal resistance on the coating surface for each pipeline:

Where is the heat transfer coefficient on the coating surface

Thermal resistance of each heat pipe:

The equivalent internal and external diameters of the channel are equal:

Where and are the area and perimeter of the channel in internal dimensions; and - area and perimeter of the channel in external dimensions.

Taking the heat transfer coefficient on the inner surface of the channel, we calculate the thermal resistance on the surface of the channel:

Thermal resistance of the channel walls at the thermal conductivity coefficient of the reinforced concrete channel wall.

The total thermal resistance to the heat flow from the air in the channel to the environment.

The air temperature in the channel is determined by the expression:

Specific heat losses by supply and return insulated heat pipes:

Total specific heat losses:

Under the condition of uninsulated heat pipes, the total thermal resistance will be equal to the thermal resistance on the surface of the heat pipe:

Air temperature in the duct with uninsulated heat pipes:

Specific heat losses from non-insulated heat pipes:

The total heat loss by uninsulated heat pipes will be equal to the heat loss by the supply heat pipe:

Thermal insulation efficiency:

From the results obtained it is clear that insulating uninsulated areas and restoring the integrity of existing insulation leads to a significant reduction in heat loss from the surface of pipelines. Thus, insulation of pipelines is a priority energy-saving measure.

Conclusion

The economic efficiency of centralized heat supply systems at the current scale of heat consumption largely depends on the thermal insulation of equipment and pipelines. Thermal insulation serves to reduce heat losses and provide permissible temperature isolated surface.

The struggle to reduce transport heat losses in heat pipelines is the most important means of saving fuel resources. Additional costs associated with applying thermal insulation and anti-corrosion coatings, are relatively small and account for 5-8% of total cost heating networks, but high-quality insulation increases the metal’s resistance to corrosion, which significantly increases the service life of pipelines. Heat losses when insulating pipelines are reduced by 10-15 times when laying above ground, and by 3-5 times when laying underground compared to uninsulated pipelines. Thermal insulation improves the working conditions of personnel and allows you to maintain high coolant parameters at a great distance from the heat source.

The choice of insulation thickness is determined by considerations of technical and economic feasibility.

Literature

1. Danilov O.L., Garyaev A.B., I.V. Yakovlev. Energy saving in heat power engineering and heat technologies. M.: MPEI Publishing House, 2010.

2. Yanovsky F.B. Energy strategy and development of heat supply in Russia / F.B. Yanovsky, S.A. Mikhailova // Energy saving. - 2003. - No. 6. - P. 26-32.

3. Varfolomeev Yu.M., Kokorin O.Ya. Heating and heating networks. M.: INFRA-M, 2010.

4. Ivanov V.V., Vershinin L.B. Distribution of temperatures and heat flows in the area of ​​heating mains // Second Russian National Conference on Heat Transfer. Thermal conductivity, thermal insulation. - M., 1998. T. 7. P. 103-105.

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Water losses in heating networks: methods for reducing the volume of leaks

Water losses in heating networks: methods for reducing leakage volumes

The task of reducing water losses is very urgent today. Coolant leaks and, as a consequence, significant heat losses exist on most existing networks. As a result, the volume of necessary make-up water and the cost of its preparation increase.

Main causes of leaks:

• Destruction of pipes due to corrosion.
• Poor fit of control and shut-off valves.
• Violations of the integrity of the pipeline under the influence of mechanical loads that occur due to poor-quality installation.

To replenish leaks, the energy of a heat source is required (make-up water is heated to a certain temperature), which leads to unnecessary costs.

Hot water losses can be:

• emergency;
• permanent.

Constants in heating networks depend on the area of ​​leaky areas and pressure. Accidental leaks are associated with pipeline ruptures. Loss of cold water (cooled coolant) due to accidents is quite rare. The vast majority of accidents occur on supply pipelines. High-temperature water moves through them under fairly high pressure.

According to current standards, when operating a heating network, coolant leakage per hour should be no more than 0.25% of the total volume.

To reduce heat loss caused by water leaks, it is necessary to regularly carry out preventive measures.

Such measures include:

• Protection of pipes from electrochemical corrosion. To do this, cathodic protection is performed and anti-corrosion agents are applied.
• High-quality water treatment. To slow down pipeline corrosion, the amount of oxygen dissolved in water is reduced.
• Periodic assessment of the residual life of pipes. Thanks to this, it is possible to promptly identify sections of the pipeline that need to be replaced. This can significantly reduce the risk of accidents and, as a result, reduce water losses.

Water balance of heating networks

At any facility that supplies heat, the efficiency of operation is determined every month. In particular, they calculate the balance of water supplied and delivered to end consumers. An imbalance may indicate either significant leaks or incorrect measurements or calculations. For example, when performing calculations, the error of measuring instruments is not taken into account.

If there is a large imbalance, it makes sense to order network diagnostics, which will determine it technical condition and the possibility of further exploitation. Engineering diagnostics is a whole complex of works. A visual inspection of the pipeline is carried out, which allows identifying pockets of corrosion. Using ultrasound diagnostics, pipe thickness measurements are performed.

Hidden leaks are detected through correlation and acoustic diagnostics. An analysis of technical documentation and the necessary engineering calculations are also performed. The customer is presented with a conclusion that indicates the remaining resource, the technical condition of the network and recommendations.

Preface

There are several reasons for heat loss in a house, and each of them can be, if not completely eliminated, then at least partially localized. According to Gosstroy research, two-thirds of the energy generated in the country “dissolves in the air.”

Contents

There are several reasons for heat loss in a house, and each of them can be, if not completely eliminated, then at least partially localized. According to Gosstroy research, two-thirds of the energy generated in the country “dissolves in the air.” Before reducing heat loss at home, you need to find out why the street is heated instead of heating the room and, despite the fire radiators, it is cold in the apartment.

You can understand how a house loses heat if you remember some physical laws.

The main reasons for heat loss at home are the following factors:

• conductivity. Since the house is built on cold ground, due to thermal conductivity heat flows go into the soil;
• convection. When the heating is on, the walls and roof become warm from the inside. As a result of thermal conductivity, heat moves to the outside of the walls and roof. At the same time, the atmosphere surrounding them, being colder, heats up due to them and takes away some of the heat, carrying it upward.

Thus, we can say that the thermal conductivity of building materials and the difference between the temperatures in the house and outside are the two main factors influencing the heat loss of a house.

At the same time, the main heat losses occur through the enclosing structures of the house: the walls account for 35% of heat loss, the roof - 25%, through the basement floor and all kinds of cracks - 15% each, through windows - 10%. A certain amount of heat can be carried out of the house.

A special examination called thermal imaging diagnostics. If you invite services specializing in it, the survey will reveal specific locations of heat leaks; quality, defects and damage to the thermal insulation of attic and basement floors and pipes; cold bridges; condition, etc.

How to reduce heat loss at home: thermal insulation of walls and windows

Understanding the causes of heat loss raises a natural question: how to eliminate heat loss at home, at least significantly reduce it? The answer is obvious - to radically improve the thermal insulation of walls, roofs, ceilings, windows, which will increase the temperature in the house without increasing heating costs.

With high-quality thermal insulation of the house, even when the air temperature drops to -25 ° C and the heating is turned off, the temperature inside the house will drop by only 1 ° C per day. It is clear that heating costs in such a house are not so burdensome.

If you don't know how to reduce heat loss at home, start by inspecting the windows: check the opening and closing mechanisms, and adjust them if necessary. If gaps are found between the window blocks and the walls, they also need to be hermetically sealed. A reflective coating can be applied to the glass. It will help reduce heat loss and glazing of balconies and loggias.

Another way to reduce heat loss at home is to insulate doors, and it is advisable to install a second door, which will additionally act as a sound insulator.

How to reduce heat loss at home: insulating the roof and basement

In addition, the walls, roof and basement must be insulated. It should be noted that it is necessary to insulate the house not from the inside, but from the outside. If you do this from the side of the room, then condensation will accumulate between the wall and the internal thermal insulation, which will not only worsen the thermal insulation of the house, but will also lead to damage to the finish and the proliferation of fungi. For external thermal insulation suitable material such as extruded polystyrene foam; the installation of a ventilated façade, etc. has proven itself well.

For thermal insulation of roofs, as a rule, stone or mineral wool is used, which are sold in the form of slabs. At the same time, we must not forget about the vapor barrier (it is advisable that its side facing inward be covered aluminum foil, which will prevent heat loss from radiation).

If the house is still just under construction, then you need to think in advance about how to reduce the perimeter of the external cold walls (the larger the square footage of the external walls, the greater the heat loss; a house decorated with numerous protruding elements loses a lot of heat), and prevent the formation of cold bridges.

Reducing heat loss at home: building a monsard

Building an attic is another way to reduce heat loss at home and reduce heat loss through the roof, since part of it is used as walls attic room. There is probably no need to talk about the fact that you should choose high-quality material for the roof.

It is unlikely that it will be possible to reduce heat loss at home to zero, but it is possible to take measures that will make it possible to stop heating the street. The first thing that comes to mind is the need to insulate the house. At the same time, we note that the cost of thermal insulation compared to how much it will cost to build a house is simply miserable. Savings on thermal insulation will certainly result in even greater losses in the future, especially since energy prices are constantly rising. By approaching home insulation as a whole, you can reduce heating costs by about 40%. This means that thermal insulation is doubly beneficial, since it reduces heat loss and minimizes energy costs.

Reducing heat loss at home: thermal insulation materials

Thermal insulation materials must meet a number of requirements, including:

• durability (this is important for its long-term operation);
• environmental friendliness (no emissions harmful to health);
• flammability (hence fire safety);
• increased vapor permeability (due to which moisture will be removed from the room and the structure of the house will remain dry);
• light weight (no need, no problems with installation, transportation of material and purchase of fasteners will not cost too much
• Naturally, price (for many this is the main determining factor).

Specifics of heat supply
The importance of solving heat supply problems is determined by several factors.

Fuel costs for heat supply are colossal. About 50 billion kW is needed only for pumping network water in centralized heating systems. h of electricity per year; and taking into account the energy consumption at heating points and for direct electric heating, the consumption of natural gas and liquid hydrocarbons for local heating of homes, the cost of organic fuel for heat supply amounts to more than 40% of everything used in the country, i.e. almost the same amount as is spent on all other industries, transport, etc. taken together. Fuel consumption by heat supply is comparable to the country's entire fuel export.
The greatest reserves for saving energy resources are also concentrated in the process of providing heat. Saving electrical energy can be achieved mainly by improving power installations (electricity sources, transport, energy-using installations at the consumer), and saving thermal energy can be achieved not only by improving heat sources, heating networks, heat-consuming installations, but also by improving the characteristics of heated objects (enclosing structures of buildings and structures, ventilation, window design, etc.).
In the electric power industry, with the adoption of a package of laws on reform, conditions have emerged for the development of competition (dependence of prices in the electricity market on time, competition of sources, etc.), which creates financial incentives for market participants to improve their energy processes to reduce costs. But the federal law “On Heat Supply” has not yet been adopted, and even with its introduction, the possibilities for creating a competition system will be greatly limited. Accordingly, where there are no market relations, it is difficult to create a system of incentives for energy saving.
There is a close connection between heat supply and fuel and gas supply systems, as well as electricity supply. Electrical energy is a substitute type of energy for district heating (DH) systems. Disruptions in central heating systems are critical for power supply systems; during severe cold snaps, the need for heat is much greater than for electricity, and when heat supply regimes are disrupted electrical energy used in the most irrational way - for heating rooms. Also, the heat load of district heating systems is the basis for district heating, i.e. use of thermal waste from the electricity production process for heat supply purposes.
As for district heating systems, not everyone has an understanding of the enormous advantages of district heating in terms of saving energy resources; they need to be explained. Aggressive advertising of individual heat sources proposed for implementation in the coverage area of ​​district heating systems with reference to foreign experience misleads consumers. In the West, programs are being adopted to support the development of district heating systems as the basis for cogeneration. Unlike our country, where historically predominantly district heating is developing, the main problem there is the difficulty of laying heating networks in cramped urban conditions and the reorientation of consumers from autonomous to centralized heat supply.

Actual loads and losses
According to the results of energy surveys, the calculated and contractual connected heat loads differ significantly from the actual ones, usually in the direction of excess. Overestimation of loads, when consumers are insufficiently equipped with metering devices and calculations based on metering devices at sources, makes it possible for heat supply organizations to underestimate excess losses in networks and, accordingly, overestimate the volumes of sold thermal energy.
Design loads are the main initial data for the development of standard energy characteristics. When they differ from the actual ones, calculated operating characteristics are obtained that are unattainable in reality. The lack of reliable standards does not allow for a full analysis of the energy efficiency of networks.
Actual loads are also important for determining the reserves of the heating system.
Heat release from sources = Consumption + Actual losses in networks
To balance the balance, you need to know at least two components. In the absence of 100% equipment with metering devices, in most cases it is easier to determine the release of heat from sources and the actual losses in the networks. Vacation, subject to verification of reliability, can be determined by thermal energy metering devices at heat sources or the fuel balance of the source if fuel metering is available. Actual losses in networks are determined using methods approved for use during the energy audit procedure, i.e. archives of metering devices available to consumers are used (at least 20% of consumers). When using these methods there is no need to carry out additional measurements and tests.
Determining actual loads and losses should be an integral part of developing the overall fuel and energy balance of the municipality.
Actual losses of network water, according to the results of energy surveys, are usually comparable to the standard leakage equal to 0.25% of the volume of heating networks per hour. In a number of regions they do not exceed the normative ones. Thus, in Moscow, the actual losses of network water and, accordingly, the losses of thermal energy with them are 2-3 times lower than the standard ones. This fact characterizes, first of all, not only the satisfactory condition of heating networks, but also inflated standards that do not reflect the capabilities of new technologies. It is necessary at the federal and regional levels to adjust the standards for network water losses downward.
Determination of thermal energy losses through thermal insulation in accordance with " Methodical instructions to determine heat losses in water heating networks (RD 34.09.255-97)” is practically not carried out anywhere. Thus, the requirements of the “Rules for Technical Operation” are violated power stations and networks of the Russian Federation." The reason is that the tests are labor-intensive and expensive, and that consumers need to be disconnected.
The results of an energy audit of heat supply systems show that actual losses in the surveyed heating networks exceed the standard ones by 1.2-2 times.
Bringing heat losses to standard values, in addition to saving thermal energy and reducing electricity costs for its transportation, will ensure the release of thermal power. At the same time, the need to build new heat sources may disappear. Thus, when assessing the economic efficiency of relocating sections of heating networks, not only the saved heat, but also the capital costs of constructing new sources should be taken into account.
It is necessary to recognize the fact of the presence of excess heat losses, which is becoming more and more obvious with the trend of increasing the proportion of consumers equipped with metering devices.
It is necessary to introduce into the practice of heat supply organizations an analysis of the state of heating networks not only in terms of the ratio of thermal energy losses to supply, but also in terms of the ratio of actual losses to standard ones. The first indicator currently used for analysis is incorrect, because it characterizes not only the state of the heating network, but also its configuration and design standards for thermal insulation.

Methods for reducing losses in heating networks
The main methods are to reduce energy losses:

periodic diagnostics and monitoring of the condition of heating networks;
drainage of canals;
replacement of dilapidated and most frequently damaged sections of heating networks (primarily those subject to flooding) based on the results of engineering diagnostics, using modern thermal insulation structures;
cleaning drains;
restoration (application) of anti-corrosion, heat and waterproofing coatings in accessible places;
ensuring high-quality water treatment of make-up water;
organization of electrochemical protection of pipelines;
restoration of waterproofing of floor slab joints;
ventilation of channels and chambers;
installation of bellows expansion joints;
use of improved pipe steels and non-metallic pipelines;
organization of real-time determination of actual thermal energy losses in main heating networks based on data from thermal energy metering devices at the thermal station and at consumers for the purpose of prompt decision-making to eliminate the causes of increased losses;
strengthening supervision during emergency recovery work by administrative and technical inspections;
transfer of consumers from central heating to individual ones heating points.

Incentives and criteria for personnel must be created. Today's task of the emergency service: come, dig, patch, fill up, leave. The introduction of only one criterion for assessing activity - the absence of repeated ruptures - immediately radically changes the situation (ruptures occur in places of the most dangerous combination of corrosion factors and increased requirements in terms of corrosion protection must be imposed on the replaced local sections of the heating network). Diagnostic equipment will immediately appear, and there will be an understanding that if this heating main is flooded, it needs to be drained, and if the pipe is rotten, then the emergency service will be the first to prove that a section of the network needs to be changed.
It is possible to create a system in which a heating network in which a rupture has occurred will be considered “sick” and will be sent for treatment to a repair service, like a hospital. After “treatment”, it will be returned to operational service with a restored resource.
Economic incentives for operating personnel are also very important. 10-20% savings from reducing losses due to leaks (subject to compliance with the network water hardness standards) paid to staff works better than any external investment. At the same time, due to the reduction in the number of flooded areas, losses through insulation are reduced and the service life of networks is increased.
Heat losses in heating networks should not exceed 5–7%, as is the case in European countries. However, our heating networks are significantly inferior to foreign ones. Currently, in most heating networks in the CIS countries, the technological consumption of thermal energy for its transportation reaches 30% of the transmitted thermal energy. This value depends on the condition of the heating networks and, first of all, on the condition of the thermal insulation.
It is necessary to radically improve the quality of replacement of heating networks through:

preliminary examination of the site being re-laid in order to determine the reasons for failure to maintain the standard service life and prepare a high-quality technical specification for the design;
mandatory development of capital repair projects with justification of the projected service life;
independent instrument testing of the quality of heating networks;
introducing personal responsibility of officials for the quality of gaskets.

The technical problem of ensuring the standard service life of heating networks was solved back in the 50s of the 20th century. due to the use of thick-walled pipes and high quality construction work, primarily anti-corrosion protection. Now the range of technical means is much wider.
Previously, technical policy was determined by the priority of reducing capital investments. It was necessary to ensure a maximum increase in production at lower costs, so that this increase would compensate for the costs of repairs in the future. In today's situation, this approach is not acceptable. In normal economic conditions the owner cannot afford to lay networks with a service life of 10-12 years; this is ruinous for him. This is especially unacceptable when the city population becomes the main payer. In every municipal formation There must be strict control over the quality of the installation of heating networks.
Priorities in spending funds must be changed, most of which is spent today on replacing sections of heating networks in which there were pipe ruptures during operation or summer pressure testing, to preventing the formation of ruptures by monitoring the rate of pipe corrosion and taking measures to reduce it.
An obvious way to reduce losses of thermal energy during its transmission through heating networks is to replace the traditional Russian laying of pipelines in mineral wool as thermal insulation with a laying in polyurethane foam or other thermal insulation that is no less effective.
Replacing stuffing box compensators with bellows ones, outdated shut-off valves with new ball valves, etc. ensures a sharp reduction in coolant losses due to its leakage, and therefore thermal energy losses.
However, there is a less obvious, but cheaper way to reduce energy costs in heat supply systems - optimizing the hydraulic operating modes of heating networks. Elimination of misadjustment of heating networks brings a reduction in thermal energy losses and electricity costs for the transfer of coolant in the heat supply system in some cases by up to 40–50%. This is explained by the fact that in order to “heat” consumers located further than others from the heat supply source, the nearest consumers have to be overheated, increasing the coolant consumption. In addition, in order to achieve at least some circulation in the heating systems of these remote buildings, they often resort to “drain” work. That is why the elimination of misregulation of heating networks and the normalization of heat supply bring a significant economic effect.
All costs for new pipes, polyurethane foam insulation, bellows expansion joints and ball valves become in vain without regulating heating networks, that is, without carrying out special work to optimize hydraulic conditions. The fact is that water heating installations of heat supply sources, their heating networks and heat consumption systems, especially when they are connected to heating networks according to a dependent scheme, represent a single complex hydraulic system, integrated general regime functioning.
The organization of hydraulic modes of operation of the heating network, in which the required distribution of coolant flow between all consumers would be ensured, is one of the most important but complex tasks. It needs to be resolved in order to improve effective work heat supply systems as a whole and each heat consumption system separately. This requires joint efforts of all organizations operating the heat supply system, since they have to deal, as was said, with a single hydraulic system– a water heating network with numerous heat consumption systems through which the coolant circulates – network water.
Because of high density Coolant water heating networks are characterized by low hydraulic stability. As a result, they are subject to misadjustment due to any disturbances - connecting or disconnecting consumers, changing the switching of the heating network, changing the coolant flow in individual heat consumption systems, for example, during the operation of hot water supply regulators, etc.
District heating systems have been in continuous change since their inception. The length of pipelines increases or, conversely, decreases due to the disconnection of some consumers. This periodically creates difficulties in organizing and managing the hydraulic modes of heating networks.
A lot of heat “escapes” through the walls, floors, ceilings, windows and doors of old buildings and structures. In old brick buildings, losses are approximately 30%, and in buildings made of concrete slabs with built-in radiators - up to 40%. Heat losses in buildings also increase due to the uneven distribution of heat in the rooms, so it is advisable to equalize the temperature difference (floor - ceiling) using ceiling fans. Due to this, heat loss can be reduced by up to 30%. To reduce heat leakage from premises, it is advisable to do air curtain.
Heat losses also increase with excessive heating. The way out of the situation is to install shields made of thermal insulation material(thermal fur coats), as well as replacement window frames double glazed windows. Since double-glazed windows have several air gaps, their installation can reduce heat loss through the windows by half. These measures are called thermal rehabilitation. They can reduce heat loss in old buildings by up to 10–15%. When constructing new buildings, thermal rehabilitation is already provided for.
Heat regulation, taking into account the orientation of the house according to parts of the world, also helps to reduce the loss of thermal energy in the premises, which we have not yet done.
The main condition normal functioning heat supply systems is to ensure in heating networks, in front of consumers' heating points, an available pressure sufficient to create a coolant flow in heat consumption systems corresponding to their thermal needs. However, due to the low hydraulic stability of heating networks under various disturbances, misadjustment occurs in them - the greater, the lower their hydraulic stability.
There is an opportunity to significantly increase the hydraulic stability of heating networks and heat supply systems.
An analysis of the functioning of many heating networks has shown that their hydraulic stability is higher, the lower the pressure loss in the pipelines of the heating networks and the greater the available pressure in front of the heating point of the most distant consumer.
To increase the hydraulic stability of heating networks, it is necessary to throttle the excess part of the available pressure using hydraulic resistances of constant or variable cross-section - throttle diaphragms and elevator nozzles or control valves of means automatic regulation. These resistances must be installed in front of each heat consumption system or in front of individual heat exchangers.
So, the adjustment of water heating networks is based on every possible increase in their hydraulic stability through the widespread installation of specially designed throttling devices - in front of each heat consumption system, regardless of its thermal load. As a result, each of the heat consumption systems in a single centralized heat supply system is placed in the same conditions compared to the others. All heat consumption systems become hydraulically equidistant from the heat supply source.
Regulation of water heating networks consists of distributing coolant flow between all connected heat consumption systems in proportion to their calculated heat load.
Regulation of the heating network comes down to adjusting the functioning of individual heat consumption systems by changing, if necessary, the hydraulic resistance and installed throttling devices.
The criteria for correct regulation of heating networks are the following indicators:
- establishing the estimated coolant flow in the heating network and in each of the heat consumption systems;
- compliance with the required temperature difference in each heat consumption system;
- maintenance in heated buildings design temperature air.
Regulation of the heating network must necessarily be preceded by a thorough examination of the heat supply system and the development of optimal operating modes for a specific heating network. Based on this, it should be developed and implemented in in full adjustment (optimization) activities.
Attempts to regulate the heating network without developing an optimal hydraulic regime and optimization measures specifically for it (and their implementation in full) lead to even greater misadjustment of the heat supply system and, consequently, to excessive costs of fuel, electricity and water to replenish the heating network.
Accounting for the supply and consumption of thermal energy and coolants is carried out in accordance with the rules for accounting for thermal energy and coolants, approved by the First Deputy Minister of Fuel and Energy of the Russian Federation on September 12, 1995.
However, the level of equipment of heat consumption systems and some heat supply sources (mainly heating boiler systems of municipal heating supply systems) does not allow calculations for the received heat energy and coolants based on the rules. Rules for the use of electrical and thermal energy, approved by Order of the Ministry of Energy and Electrification of the USSR No. 310 of December 6, 1981, were canceled in 2000.
Thus, Art. 11 Federal Law No. 28-FZ dated 04/03/1996 (as amended on 04/05/2003) “On Energy Saving” is not implemented. Accounting for thermal energy and coolants, which in itself cannot provide an energy-saving effect, but should stimulate energy saving in the process of heat supply, currently does not have a proper regulatory framework.
The functions of developing and approving rules for heat energy accounting are not mentioned either in the regulations on the Ministry of Energy or in the regulations on the Ministry of Regional Development. As a result, the rules for commercial accounting of thermal energy, reflecting the real situation, have not yet been reviewed and approved.
Program to improve the reliability of heating networks
To realize the energy saving potential, it is necessary to implement a whole range of measures, among which priority is given to measures aimed at increasing the reliability of the functioning of heating networks. The work that is being carried out in thermal organizations to reconstruct heating networks helps to increase the efficiency of transport and distribution systems of thermal energy. But very often the expected effect is not realized due to violations of the requirements of regulatory and technical documents NTD, which apply to the operation, construction and major repairs of heating networks.
Such violations during operation include:

lack of monitoring of the actual condition of heating pipelines during operation, periodic technical inspections of heating networks are not carried out;
no measures are taken to extend the service life of existing heat pipelines;
operating personnel do not know corrosion protection methods, training is not carried out and is not planned;
there is no constant monitoring of the condition of pipelines in PPU - insulation with UEC systems due to the absence or malfunction of monitoring devices;
low quality of emergency repair work;
There is no monitoring of the actual losses of thermal energy through the thermal insulation of heat pipelines, which characterize the state of heating networks.

Violations during construction and major repairs of heating networks:

major renovation is carried out without projects and analysis of the causes of premature failure of heating pipelines, which leads to the repetition of previously made mistakes;
projects for new construction of heating networks do not take into account the actual conditions of laying the route;
project design does not match regulatory documents, projects of low technical quality, errors in strength and cycle calculations, the use of steel grades not provided for by GOST, ill-conceived transportation, etc. are also submitted for approval.
the technical specifications for the design do not indicate the data on the basis of which the main measures necessary to protect against external corrosion and ensure the design service life of heat pipelines, actual operating conditions and the reasons that shortened the design service life are developed;
the projects do not have an estimated service life of heating networks;
corrosion processes are intensified due to the use of materials and products when laying heating networks that do not meet the requirements of the current normative and technical documentation;
work on the design, installation and commissioning of operational-remote control systems for pipelines in polyurethane foam insulation are carried out in violation of the requirements of the current normative and technical documentation, which leads to a reduction in the service life of heating networks below the calculated one; the quality of laying the pipes themselves in polyurethane foam insulation does not always comply with regulatory documents , low-quality components for the transition from polyurethane foam to standard thermal insulation, lack of joining of UEC sections into a single system, construction of buildings high number of storeys in close proximity to the heating network;
low qualifications of the personnel of contractors performing the work;
Heat pipelines laid in violation of the provisions of the current normative and technical documentation (quality of anti-corrosion coatings, thickness of thermal insulation, etc.) are accepted for operation.

Taking into account the above, it is necessary to include the development of a program to improve the reliability of heating networks among the priority measures. The program must formulate all measures to improve the reliability of heating networks, tested on existing heating networks, but not widely used.
The program must include a list of organizational and technical measures carried out during operation, maintenance, replacement and new construction of heating networks with justification for each activity.
Among organizational events The following should be noted:

organization of a corrosion protection service at heat supply enterprises, assigning it responsibility for coordinating the work of monitoring the corrosion state of heating networks, introducing protective measures, determining the resource, introducing methods of economic incentives, developing technical assignments in terms of corrosion protection, preparation of plans for scientific and technical work, personnel training;
restore state acceptance for operation of heating networks with independent instrument quality control of installations;
make a gradual transition from destructive methods of monitoring heating networks to non-destructive ones, massively introduce a system of local preventive repairs with the replacement of specific places of maximum corrosion destruction, with the reorientation of emergency services, from eliminating accidents to preventing them;
conduct a mandatory investigation into the causes of premature failure of heating network pipelines, identifying the causes, specific culprits and measures necessary to prevent such situations; the investigation should be carried out with the participation of representatives of Rostechnadzor;
organize mandatory training for operating personnel on corrosion protection methods in accordance with the requirements of regulatory documents.

Of course, the list of events provided does not claim to be exclusive and is not exhaustive. Because there are a great many opportunities on the path to ensuring energy efficiency, and an effective energy saving program is a product of intellectual labor, the result of joint work of an energy auditor and the energy service of an organization that is a consumer of fuel and energy resources.
Adjustment of heat supply systems
To improve the efficiency of existing energy supply systems in settlements, an effective system of monitoring the performance indicators of their work is needed.
Existing quality control heating season actually comes down to recording accidents and incidents. But this does not indicate the actual quality of heat supply (adequacy of the amount of heat consumed and its quality indicators, efficiency of using the temperature potential of the coolant, minimal costs for transport and heat distribution).
Existing system payment for the heat received takes into account only its quantity. There is a need to take into account, along with the quantity, the quality of the heat received, which involves increasing responsibility both on the part of heat supply organizations and consumers.
The adjustment of heat supply systems, designed to ensure reliable and economical distribution of coolant to consumers in accordance with their heat loads, is becoming increasingly important. In all regions of the Russian Federation, hydraulic misadjustment of heat supply systems is observed, regardless of the thermal power of thermal energy sources. The lack of adjustment work is the cause of overheating for some consumers and lack of heating for others, while there is a significant overconsumption of fuel, up to 30%. Considering that the structure of heating networks in small towns of the Russian Federation often develops chaotically, the need for adjustment work is especially acute. With rising energy prices, the need for adjustment work only increases.
The regime adjustment of the centralized heating system consists of ensuring the design temperatures inside the heated premises and the specified operating modes of air heaters, water heating and various types of technological installations that consume thermal energy from the heating network at the optimal operating mode of the system as a whole.
Regime adjustment covers the main parts of the centralized heat supply system:

water heating installation of a thermal power plant or boiler room;
central heating point (CHS);
water heating network with control and distribution points (CDP), pumping, throttle substations and other structures installed on it;
individual heating points (ITP);
local heat consumption systems.

The challenges of regulating district heating systems include:

providing a heat source for specified hydraulic and thermal conditions;
ensuring the calculated coolant flow rate for all heat consumption systems connected to the heating network, as well as for heat-consuming devices;
ensuring the calculated internal air temperatures in the room

Introduction
This article briefly describes the problems of energy saving that have developed today at the vast majority of domestic facilities for the production, transportation and consumption of thermal energy, offering options for their effective solution.

Existing thermal systems, for the most part, were designed and created without taking into account the opportunities that have appeared on the heat and power market over the past 10 years. The massive development of computer technology led to the emergence at this time huge amount technological innovations that have radically changed the situation in energy saving. For example, the ability to accurately simulate thermal processes on a computer has led to the emergence of new efficient designs boilers and heating circuits, and advances in the electronics industry have made it possible wide application thermal energy metering devices and highly economical control devices.

Thus, at the end of the twentieth century, energy conservation received a large number of effective technologies and new equipment that can significantly (up to 50%) increase the reliability and efficiency of existing thermal systems and design new systems that are qualitatively different from existing ones.

Energy saving. Axioms.

To assess the efficiency of any system, including heat and power, a generalized physical indicator is usually used - coefficient useful action(efficiency). The physical meaning of efficiency is the ratio of the value obtained useful work(energy) to expended. The latter, in turn, is the sum of the useful work (energy) received and losses arising in system processes. Thus, increasing the efficiency of the system (and therefore increasing its efficiency) can only be achieved by reducing the amount of unproductive losses that arise during operation. This is the main task of energy saving.

The main problem that arises when solving this problem is identifying the largest components of these losses and choosing the optimal technological solution that can significantly reduce their impact on the efficiency value. Moreover, each specific object - the goal of energy saving - has a number of characteristic design features and the components of its heat losses are different in magnitude. And whenever it comes to increasing the efficiency of heat and power equipment (for example, a heating system), before making a decision in favor of using any technological innovation, it is necessary to conduct a detailed examination of the system itself and identify the most significant channels of energy loss. A smart decision will use only such technologies that will significantly reduce the largest unproductive components of energy losses in the system and, at minimal cost, will significantly increase the efficiency of its operation.

However, despite the uniqueness in general case factors causing losses in each specific thermal system, domestic facilities have a number characteristic features. They are very similar to each other, which is due to the fact that they were built according to design standards common to the Soyuz at a time when thermal energy cost “a penny.” The characteristic problems and main channels of heat loss in the power systems of “post-Soviet” facilities have been well studied by the specialists of our enterprise. We have worked out the solution to the vast majority of energy saving problems in them in practice, which allows us to analyze, consider the most typical situations with heat losses and propose options for their solution with predicting results, based on our experience of working with similar situations at other facilities.

The study below examines the most characteristic problems existing thermal facilities, describes the most significant channels of unproductive losses of thermal energy in them and offers options for reducing these losses with a preliminary forecast of the results.

Thermal systems. Sources of losses.

For the purpose of analysis, any heat and power system can be divided into 3 main sections:

1. thermal energy production area (boiler room);

2. area for transporting thermal energy to the consumer (heating network pipelines);

3. area of ​​thermal energy consumption (heated facility).

Each of the above sections has characteristic unproductive losses, the reduction of which is the main function of energy saving. Let's look at each section separately.

1. Thermal energy production site. Existing boiler room.

The main link in this section is the boiler unit, the functions of which are to convert the chemical energy of the fuel into thermal energy and transfer this energy to the coolant. A number of physical and chemical processes occur in the boiler unit, each of which has its own efficiency. And any boiler unit, no matter how perfect it is, necessarily loses some of the fuel energy in these processes. A simplified diagram of these processes is shown in the figure.

At the thermal energy production site at normal operation In a boiler unit, there are always three types of main losses: with underburning of fuel and exhaust gases (usually no more than 18%), energy losses through the boiler lining (no more than 4%) and losses with purging and for the own needs of the boiler room (about 3%). The indicated heat loss figures are approximately close for a normal, not new, domestic boiler (with an efficiency of about 75%). More advanced modern boiler units have a real efficiency of about 80-85% and their standard losses are lower. However, they can increase further:

If routine adjustment of the boiler unit with an inventory of harmful emissions is not carried out in a timely and efficient manner, losses due to underburning of gas may increase by 6-8%; Diameter of burner nozzles installed on the boiler unit medium power usually not recalculated for the actual boiler load. However, the load connected to the boiler is different from that for which the burner is designed. This discrepancy always leads to a decrease in heat transfer from the torches to the heating surfaces and an increase of 2-5% in losses due to chemical underburning of the fuel and exhaust gases; If the surfaces of boiler units are cleaned, as a rule, once every 2-3 years, this reduces the efficiency of a boiler with contaminated surfaces by 4-5% due to an increase in losses with flue gases by this amount. In addition, insufficient operating efficiency of the chemical water treatment system (CWT) leads to the appearance of chemical deposits (scale) on the internal surfaces of the boiler unit, significantly reducing its operating efficiency. If the boiler is not equipped complete set means of control and regulation (steam meters, heat meters, systems for regulating the combustion process and heat load) or if the control means of the boiler unit are not configured optimally, then on average this further reduces its efficiency by 5%. If the integrity of the boiler lining is violated, additional air suction into the firebox occurs, which increases losses due to underburning and flue gases by 2-5%. Use of modern pumping equipment in the boiler room allows you to reduce electricity costs for the boiler room’s own needs by two to three times and reduce the costs of their repair and maintenance. Each start-stop cycle of the boiler unit consumes a significant amount of fuel. The ideal option for operating a boiler room is its continuous operation in the power range determined by the regime map. The use of reliable shut-off valves, high-quality automation and control devices allows us to minimize losses arising due to power fluctuations and emergency situations in the boiler room.

The sources of additional energy losses in the boiler room listed above are not obvious and transparent for their identification. For example, one of the main components of these losses - losses due to underburning - can only be determined using a chemical analysis of the composition of the flue gases. At the same time, an increase in this component can be caused by a number of reasons: the correct fuel-air mixture ratio is not maintained, there are uncontrolled air suctions into the boiler furnace, the burner device is operating in a non-optimal mode, etc.

Thus, constant implicit additional losses only during heat production in the boiler room can reach 20-25%!

An algorithm for increasing the operating efficiency of an existing boiler unit can generally be represented as a sequence of certain actions (in order of effectiveness):

1. Conduct comprehensive examination boiler units, including gas analysis of combustion products. Assess the quality of work of peripheral equipment of the boiler room.

2. Carry out routine adjustment of boilers with an inventory of harmful emissions. Develop regime cards operation of boiler units at various loads and measures that will ensure the operation of boiler units only in economical mode.

3. Clean the external and internal surfaces of the boiler units.

4. Equip the boiler room with working control and regulation devices, optimally configure the automation of boiler units.

5. Restore the thermal insulation of the boiler unit by identifying and eliminating uncontrolled sources of air suction into the furnace;

6. Check and possibly upgrade the boiler room’s water treatment system.