Types of boiler rooms. General information about boiler plants, types of boilers for building heat supply

A boiler plant (boiler room) is a structure in which heating is carried out. working fluid(heat carrier) (usually water) for a heating or steam supply system, located in one technical room. Boiler rooms are connected to consumers by means of a heating main and/or steam pipelines. The main device of the boiler house is a steam, fire-tube and / or hot water boilers. Boilers are used for centralized heat and steam supply or for local heat supply of buildings.

A boiler plant is a complex of devices located in special rooms and serving to convert the chemical energy of fuel into thermal energy of steam or hot water. Its main elements are a boiler, a combustion device (furnace), feed and draft devices. In general, a boiler plant is a combination of a boiler (boilers) and equipment, including the following devices: fuel supply and combustion; purification, chemical treatment and deaeration of water; heat exchangers for various purposes; source (raw) water pumps, network or circulation pumps - for circulating water in the heat supply system, make-up pumps - to compensate for water consumed by the consumer and leaks in networks, feed pumps for supplying water to steam boilers, recirculating (mixing); nutritious, condensing tanks, hot water storage tanks; blow fans and air path; smoke exhausters, gas path and chimney; ventilation devices; systems automatic regulation and fuel combustion safety; heat shield or control panel.

The boiler is heat exchange device, in which the heat from the hot combustion products of the fuel is transferred to the water. As a result, in steam boilers, water is converted into steam, and in hot water boilers it is heated to the required temperature.

The combustion device serves to burn fuel and convert its chemical energy into heat of heated gases.

Feeding devices (pumps, injectors) are designed to supply water to the boiler.

The draft device consists of blowers, a system of gas ducts, smoke exhausters and a chimney, with the help of which the supply of required amount air into the furnace and the movement of combustion products through the gas ducts of the boiler, as well as their removal into the atmosphere. Combustion products, moving along the gas ducts and in contact with the heating surface, transfer heat to the water.

To ensure more economical operation, modern boiler plants have auxiliary elements: water economizer and air heater, respectively, for heating water and air; fuel supply and ash removal devices, for cleaning flue gases and feed water; thermal control devices and automation equipment that ensure the normal and uninterrupted operation of all parts of the boiler room.

Depending on the use of their heat, boiler houses are divided into energy, heating and production and heating.

Power boilers supply steam steam power plants generating electricity, and are usually part of a power plant complex. Heating and production boiler houses are found in industrial enterprises and provide heat to the heating and ventilation systems, hot water supply of buildings and technological processes production. Heating boilers solve the same problems, but serve residential and public buildings. They are divided into separate, interlocked, i.e. adjacent to other buildings, and built into buildings. AT recent times more and more often stand-alone enlarged boiler houses are being built with the expectation of serving a group of buildings, a residential quarter, a microdistrict.

The installation of boiler houses built into residential and public buildings is currently allowed only with appropriate justification and coordination with the sanitary supervision authorities.

Boiler houses low power(individual and small group) usually consist of boilers, circulation and make-up pumps and draft devices. Depending on this equipment, the dimensions of the boiler room are mainly determined.

2. Classification of boiler plants

Boiler plants, depending on the nature of consumers, are divided into energy, production and heating and heating. According to the type of heat carrier obtained, they are divided into steam (for generating steam) and hot water (for generating hot water).

Power boiler plants produce steam for steam turbines at thermal power plants. Such boiler houses are equipped, as a rule, with boiler units of large and medium power, which produce steam with increased parameters.

Industrial heating boiler plants (usually steam) produce steam not only for industrial needs, but also for heating, ventilation and hot water supply.

Heating boiler plants (mainly water-heating, but they can also be steam) are designed to service heating systems for industrial and residential premises.

Depending on the scale of heat supply, heating boiler houses are local (individual), group and district.

Local boiler houses are usually equipped hot water boilers with water heating up to a temperature not exceeding 115 °C or steam boilers with working pressure up to 70 kPa. Such boiler houses are designed to supply heat to one or more buildings.

Group boiler plants provide heat to groups of buildings, residential areas or small neighborhoods. They are equipped with both steam and hot water boilers of greater heat output than boilers for local boiler houses. These boiler houses are usually located in specially constructed separate buildings.

District heating boiler houses are used to supply heat to large residential areas: they are equipped with relatively powerful hot water or steam boilers.

Rice. one.

Rice. 2.

Rice. 3.

Rice. 4.

Individual elements It is customary to conditionally show the schematic diagram of a boiler plant in the form of rectangles, circles, etc. and connect them with each other with lines (solid, dotted) denoting the pipeline, steam pipelines, etc. circuit diagrams steam and hot water boiler plants, there are significant differences. A steam boiler plant (Fig. 4, a) of two steam boilers 1, equipped with individual water 4 and air 5 economizers, includes a group ash catcher 11, to which the flue gases are supplied along the collecting hog 12. To suck the flue gases in the area between the ash catcher 11 and smoke exhausters 7 with electric motors 8 are installed in the chimney 9. Gates (flaps) 10 are installed for the operation of the boiler room without smoke exhausters.

Steam from the boilers through separate steam lines 19 enters the common steam line 18 and through it to the consumer 17. Having given off heat, the steam condenses and returns to the boiler room through the condensate line 16 to the collection condensate tank 14. Through the line 15, additional water is supplied to the condensate tank from the water supply or chemical water treatment (to compensate for the volume not returned from consumers).

In the event that part of the condensate is lost at the consumer, a mixture of condensate and additional water is supplied from the condensate tank by pumps 13 through the supply pipeline 2, first to the economizer 4, and then to the boiler 1. The air necessary for combustion is sucked in by centrifugal draft fans 6 partially from the room boiler room, partly from the outside and through air ducts 3 is supplied first to the air heaters 5, and then to the furnaces of the boilers.

The hot water boiler plant (Fig. 4, b) consists of two hot water boilers 1, one group water economizer 5 serving both boilers. Flue gases leaving the economizer through a common collection hog 3 enter directly into the chimney 4. The water heated in the boilers enters the common pipeline 8, from where it is supplied to the consumer 7. Having given off heat, the cooled water is first sent through the return pipeline 2 to the economizer 5 and then back to the boilers. Water by closed loop(boiler, consumer, economizer, boiler) is moved by circulation pumps 6.

Rice. 5. : 1 - circulation pump; 2 - firebox; 3 - superheater; 4 - upper drum; 5 - water heater; 6 - air heater; 7 - chimney; eight - centrifugal fan(smoke exhauster); 9 - fan for supplying air to the air heater

On fig. 6 shows a diagram of a boiler unit with a steam boiler having an upper drum 12. A furnace 3 is located in the lower part of the boiler. Nozzles or burners 4 are used to burn liquid or gaseous fuel, through which fuel is supplied to the furnace along with air. Boiler limited brick walls- lining 7.

When fuel is burned, the released heat heats the water to a boil in pipe screens 2 installed on inner surface furnace 3, and ensures its conversion into water vapor.

Fig 6.

Flue gases from the furnace enter the boiler gas ducts, formed by lining and special partitions installed in pipe bundles. When moving, the gases wash the bundles of pipes of the boiler and superheater 11, pass through the economizer 5 and the air heater 6, where they are also cooled due to the transfer of heat to the water entering the boiler and the air supplied to the furnace. Then, the significantly cooled flue gases are removed by means of a smoke exhauster 17 through the chimney 19 into the atmosphere. Flue gases from the boiler can also be discharged without a smoke exhauster under the action of natural draft generated by the chimney.

Water from the source of water supply through the supply pipeline is supplied by pump 16 to the water economizer 5, from where, after heating, it enters the upper drum of the boiler 12. The filling of the boiler drum with water is controlled by the water-indicating glass installed on the drum. In this case, the water evaporates, and the resulting steam is collected in the upper part of the upper drum 12. Then the steam enters the superheater 11, where it is completely dried due to the heat of the flue gases, and its temperature rises.

From the superheater 11, steam enters the main steam pipeline 13 and from there to the consumer, and after use it condenses and returns in the form of hot water (condensate) back to the boiler room.

Losses of condensate at the consumer are replenished with water from the water supply system or from other sources of water supply. Before entering the boiler, water is subjected to appropriate treatment.

The air necessary for fuel combustion is taken, as a rule, from the top of the boiler room and is supplied by the fan 18 to the air heater 6, where it is heated and then sent to the furnace. In boiler rooms of low power, air heaters are usually absent, and cold air is supplied to the furnace either by a fan or due to rarefaction in the furnace created by a chimney. Boiler plants are equipped with water treatment devices (not shown in the diagram), instrumentation and appropriate automation equipment, which ensures their uninterrupted and reliable operation.

Rice. 7.

For the correct installation of all elements of the boiler room, use wiring diagram, an example of which is shown in Fig. nine.

Rice. nine.

Hot water boiler plants are designed to produce hot water used for heating, hot water supply and other purposes.

To ensure normal operation, boiler rooms with hot water boilers are equipped with the necessary fittings, instrumentation and automation equipment.

A hot water boiler house has one heat carrier - water, in contrast to a steam boiler house, which has two heat carriers - water and steam. In this regard, in the steam boiler house it is necessary to have separate pipelines for steam and water, as well as tanks for collecting condensate. However, this does not mean that the schemes of hot water boilers are simpler than steam ones. Water-heating and steam boiler plants vary in complexity depending on the type of fuel used, the design of boilers, furnaces, etc. Both a steam and a water-heating boiler plant usually include several boiler units, but not less than two and not more than four to five . All of them are interconnected by common communications - pipelines, gas pipelines, etc.

The device of boilers of lower power is shown below in paragraph 4 of this topic. To better understand the device and the principles of operation of boilers different power, it is desirable to compare the device of these less powerful boilers with the device of the larger boilers described above, and find in them the main elements that perform the same functions, as well as understand the main reasons for the differences in designs.

3. Classification of boiler units

Boilers as technical devices for the production of steam or hot water are diverse constructive forms, principles of operation, types of fuel used and production indicators. But according to the method of organizing the movement of water and steam-water mixture, all boilers can be divided into the following two groups:

Boilers with natural circulation;

Boilers with forced movement of the coolant (water, steam-water mixture).

In modern heating and heating-industrial boiler houses for the production of steam, boilers with natural circulation are mainly used, and for the production of hot water - boilers with forced movement of the coolant, operating on the direct-flow principle.

Modern natural circulation steam boilers are made from vertical pipes located between two collectors (upper and lower drums). Their device is shown in the drawing in fig. 10, a photograph of the upper and lower drum with pipes connecting them - in fig. 11, and placement in the boiler room - in fig. 12. One part of the pipes, called heated "lifting pipes", is heated by a torch and combustion products of fuel, and the other, usually not heated part of the pipes, is located outside the boiler unit and is called "down pipes". In heated riser pipes, water is heated to a boil, partially evaporates and enters the boiler drum in the form of a steam-water mixture, where it is separated into steam and water. Through downcomer unheated pipes, water from the upper drum enters the lower collector (drum).

The movement of the coolant in boilers with natural circulation is carried out due to the driving pressure created by the difference in the weights of the water column in the downcomer and the column of the steam-water mixture in the riser pipes.

Rice. ten.

Rice. eleven.

Rice. 12.

In steam boilers with multiple forced circulation, the heating surfaces are made in the form of coils that form circulation circuits. The movement of water and steam-water mixture in such circuits is carried out using circulation pump.

In once-through steam boilers, the circulation ratio is one, i.e. Feed water, heating up, successively turns into a steam-water mixture, saturated and superheated steam.

In hot water boilers, when moving along the circulation circuit, water is heated in one revolution from the initial to the final temperature.

According to the type of heat carrier, boilers are divided into water-heating and steam boilers. The main indicators of a hot water boiler are thermal power, that is, heat output, and water temperature; The main indicators of a steam boiler are steam output, pressure and temperature.

Hot water boilers, the purpose of which is to obtain hot water of specified parameters, are used for heat supply of heating and ventilation systems, domestic and technological consumers. Hot water boilers, usually operating on a once-through principle with a constant water flow, are installed not only at thermal power plants, but also in district heating, as well as heating and industrial boiler houses as the main source of heat supply.

Rice. thirteen.

Rice. fourteen.

According to the relative movement of heat exchange media (flue gases, water and steam), steam boilers (steam generators) can be divided into two groups: water tube boilers and fire tube boilers. In water-tube steam generators, water and a steam-water mixture move inside the pipes, and the flue gases wash the pipes from the outside. In Russia in the 20th century, Shukhov's water-tube boilers were predominantly used. In fire tubes, on the contrary, flue gases move inside the pipes, and water washes the pipes from the outside.

According to the principle of movement of water and steam-water mixture, steam generators are divided into units with natural circulation and forced circulation. The latter are subdivided into direct-flow and with multiple-forced circulation.

Examples of placement in boiler boilers of different capacities and purposes, as well as other equipment, are shown in fig. 14-16.

Rice. fifteen.

Rice. sixteen. Examples of placement of household boilers and other equipment

Currently, there is a great variety of boiler heating systems. Their future functionality determines the potential configuration of boiler equipment, and the list of components for such systems is very, very impressive. This article will tell you about boiler equipment for the home, its features and purpose in the general heating system.

Boiler

The heart of any heating system is the boiler. A thermal boiler is a device that is a closed structure, where the coolant takes over thermal energy from heating elements or heat from burning fuel.

Below is a short list important features boilers.

Fuel type

AT this moment on the market it will not be difficult to find boilers adapted for liquid, gas, solid fuels, as well as for electricity.
Gas boilers have gained the most popularity. They make up about 70%, which, however, is natural, given the prevalence of gas pipelines and the low cost of gas.

Diesel boilers proudly follow. An important factor in their use is a replaceable burner, which allows it to be used in boilers of various designs.

Solid fuel boilers are the oldest representative of these mechanisms, their advantage is autonomy from the power supply, as well as high efficiency.

The list is closed by electric heating boilers- the built-in equipment of the boiler room in the house allows you to adjust the temperature program, but they are rarely used on their own, most often they act as a reserve for solid fuel boilers in case the fuel burns out, which is effective for small rooms.

Power

The parameter shows the efficiency of installing a particular boiler in specific conditions. For its calculation, a team of specialists is required, the calculation process itself depends on a number of factors, ranging from the size of the room to the purpose of the heated rooms.

one more important parameter is the number of circuits. A single-circuit boiler is able to warm up the room, but a double-circuit boiler is able to provide hot water for domestic needs.

Installation method

Floor and wall. Most often, these parameters are applied to gas boilers. wall variant perfectly saves space in the room, at the same time, the concept of one or two circuits is often applicable to them. Single-circuit systems provide the house with heat, and together with a boiler indirect heating and hot water, and dual-circuit ones are able to provide small house hot water.

Worth mentioning universal options boilers. An example is a boiler with a combustion chamber for solid fuels and with additional equipment a boiler room in the house that burns gas or liquid fuels.

Another option is a wood-gas boiler. When wood is burned, a process takes place in it that produces a flammable gas, which, in turn, is burned in the boiler, significantly increasing efficiency.

Indirect heating boiler

To provide the house with hot water, an indirect heating boiler is located in the boiler room. Water heating in the boiler comes from the same boiler that heats the home. Indirect heating boilers are floor and wall.

The advantages of such a boiler include:

• high performance at correct installation;
• providing water without prior draining;
• economy.

But it also has disadvantages:

• with frequent heating, the amount of heat given off to heat the premises decreases.

Circulation pump

Many heating systems use the principle natural circulation coolant, but there is a more advanced version of the movement of the liquid. It is achieved by installing circulation pumps in the pipes, as well as necessary equipment boiler room in the house, resulting in increased efficiency of the entire heating system. This is due to an increase in the speed of the coolant. Due to the accelerating movement of the coolant, heating and heat transfer occur as quickly as possible, as a result of which it becomes possible to reduce the diameter of the pipes and reduce the load on the boiler.

The structure of the pump is very simple, it is most often a cast-iron casing, inside which a rotor rotates with an impeller attached to it. The most interesting thing is that, despite the amount of liquid being pushed, a quality rotor makes almost no noise when installed correctly. One of the main principles of installation is - strictly horizontal position rotor. It is recommended to pay attention to products of German and Italian production, as they are considered the highest quality and relatively inexpensive.

distribution manifold

This is the equipment of the boiler house, which controls the processes in each individual heating circuit. This part of the system is perfectly adapted for systems of the type and various types radiators. This system, intricate at first glance, is designed by its existence to establish a proportional distribution of heat flows from the boiler to heat consumers. Thanks to the existence of this system, the temperature in each individual part of the living space is easily regulated.

The appearance of this boiler room equipment in the house can be described as follows - it is a metal comb with a certain number of leads to which the coolant is supplied from the boiler and which distribute the coolant over all heating circuits. Outwardly, they differ little, but there is a significant difference in the materials of manufacture and the complexity of the design. Most often they are made of steel, copper, brass and polymers. Simple combs are limited in the capabilities of the device, while being modified with a variety of sensors, control units, as well as electronic valves and air outlets.

Installing a collector system guarantees the most reasonable distribution of heat in the house, but it should be borne in mind that this system is useless without the use of circulation pumps, and the technology itself has a rather high price.

Hydrogun

At the water gun as a representative boiler house equipment there are a number of other names, it can be called a hydraulic separator, a hydrodynamic thermal separator, a "bottle". This device has enough simple form- this is a cylindrical or rectangular vertical structure with branch pipes located opposite each other: two on each side (however, there may be more). Its functionality is to separate the temperature and flows of the coolant within the outlet and inlet of the coolant into the boiler, thanks to its work, the efficiency increases significantly, but only if it is suitable for your heating system, which most often requires accurate and error-free calculations. It is important to consider that for the functioning of the hydraulic gun, the presence of a circulation pump in the system is indispensable; it must be assigned to each circuit.

Expansion tank

Also important equipment of the boiler room in the house. The boiler system is filled with a coolant, most often it is, of course, water, but when the system is heated, there may be a tendency to form overpressure against the background of thermal expansion of the liquid. In order to avoid breakdowns and any violations in the integrity of the heating system, an expansion tank is used.

There are two types of tanks for boiler room equipment in the house. The first one is open, at the moment it has almost ceased to be used, technically it compensates for the change in the volume of the coolant, opening an outlet to the atmosphere, but this technology is extremely rough, it requires constant monitoring and topping up of liquid, it is difficult to install and often shows its tendency to corrosion.

Closed tanks (or membranes) soon replaced the open ones. Most often they have a sealed cylindrical shape made of steel. The internal volume of these tanks is occupied by a membrane that separates inert gas or excess air from excess coolant coming from the boiler system during its expansion. Under the pressure of the liquid, the air is compressed, but as soon as the temperature (and, consequently, the pressure) drops, the gas returns to its original volume and, using the membrane, pushes the coolant back into the system for its further circulation.

Pipes

Even such a seemingly trifle of boiler room equipment in the house should be closely treated.
It is quite logical that they are very popular metal pipes. The most common materials for them are steel and copper. Steel pipes- perfectly tolerate high temperatures, withstand high pressure, have a low price, but, unfortunately, are very prone to corrosion. Copper pipes are not prone to rust damage and are recognized the best option for home heating but they are quite expensive.

Equivalents copper pipes- polypropylene pipes. They are not prone to rust, are extremely resistant to high temperatures and aggressive substances, and have a large margin of safety also due to their smooth structure. They are cheaper than copper, therefore, at the moment they are the most (and it should be noted, well-deserved) popularity.

Also known metal-plastic pipes, in fact, this is nothing more than pipes reinforced with some kind of metal from the same polypropylene, they literally combine the best of possible properties the materials described above. Moreover, they are able to change their shape and bend in any necessary way.

In modern energy, the most different kinds boiler rooms. They can be classified by type of fuel, type of coolant, type of placement, level of mechanization. A certain type of boiler house is selected depending on the goals and objectives, operating conditions and customer requirements.

1. By type of fuel

• Gas. The advantage of this type of boiler is that gas is one of the most economical and environmentally friendly fuels. Gas boilers do not require complex and bulky fuel supply and ash removal equipment and can be fully automated.
• Liquid fuel. These boilers can operate on waste oil, fuel oil, diesel fuel, oil. They are quickly put into operation, do not require special permits, connection approval, obtaining gas limits (unlike gas ones).
• Solid fuel. Solid fuels include coal, peat, firewood, pellets and briquettes from timber processing waste and Agriculture. The advantage of this type of boiler is the availability and low price fuel, but installation of fuel supply and ash removal systems is required.

2. By type of coolant

• Steam. In such a boiler house, the heat carrier is steam, which is used mainly to ensure production processes at industrial enterprises.
• Water heating. This type of boiler is designed for heating and hot water supply of residential buildings, industrial and municipal facilities. The heat carrier is water heated up to +95 +115 °С.
• Combined. These boilers house both steam and hot water boilers. Hot water is used to cover the load on hot water supply, heating and ventilation, and steam is supplied to meet the technological needs of the enterprise.
• in diathermic oil. This boiler house uses organic high-temperature liquids as a heat carrier, the temperature of which can reach +300 °C.

3. By type of accommodation

• Block-modular. This type of boiler houses is becoming more and more popular in Russia in last years due to many advantages compared to stationary boilers: fast installation and commissioning, factory readiness of modules, the possibility of increasing power by adding blocks, autonomy, high efficiency, mobility. Depending on the location, block-modular boiler rooms can be freestanding, attached, built-in, roof, basement.
• Stationary. Stationary boiler houses, as a rule, are built when the required power exceeds 30 MW or the construction of a block-modular boiler house is impossible for some reason. Stationary boiler houses are distinguished by the capital nature of construction (foundations, walls and partitions, roofing). Installation of equipment is carried out on site.

4. By the level of mechanization

Depending on the degree of mechanization / automation of processes, there are the following types boiler houses:

• Manual. Small boiler houses can be equipped with boilers that are fed manually by operators. Fuel is supplied to the boiler room by a trolley or, in some cases, through a bunker with external loading. Ash and slag from the ash bin are also manually removed by the operator and taken out of the boiler room using a trolley.
• Mechanized. Modern solid fuel boilers are equipped with mechanization tools that greatly facilitate the work of the boiler operator. Fuel supply is carried out using conveyors or skip hoists. Coal passes pre-processing on coal crushers, metal and chip traps. Ash and slag can be removed various methods- mechanical, hydraulic, pneumatic or a combination thereof.
• Automated. This type of boiler houses assumes full automation and minimal presence of the human factor. As a rule, gas boilers are fully automated.

1. Boiler plants

1.1 General information and concepts of boiler plants

A boiler plant is a complex of devices located in special rooms and serving to convert the chemical energy of fuel into thermal energy of steam or hot water. The main elements of the boiler plant are the boiler, the combustion device (furnace), feed and draft devices.

A boiler is a heat exchange device in which heat from hot fuel combustion products is transferred to water. As a result, in steam boilers, water is converted into steam, and in hot water boilers it is heated to the required temperature.

The combustion device serves to burn fuel and convert its chemical energy into heat of heated gases.

Feeding devices (pumps, injectors) are designed to supply water to the boiler.

The draft device consists of blowers, a system of gas ducts, smoke exhausters and a chimney, with the help of which the necessary amount of air is supplied to the furnace and the movement of combustion products through the boiler flues, as well as their removal into the atmosphere. Combustion products, moving along the gas ducts and in contact with the heating surface, transfer heat to the water.

To ensure more economical operation, modern boiler plants have auxiliary elements: a water economizer and an air heater, which serve to heat water and air, respectively; devices for fuel supply and ash removal, for cleaning flue gases and feed water; thermal control devices and automation equipment that ensure the normal and uninterrupted operation of all parts of the boiler room.

Depending on the purpose for which it is used thermal energy, boiler houses are divided into energy, heating and production and heating.

Power boilers supply steam to power plants that generate electricity and are usually part of a power plant complex. Heating and production boiler houses are built at industrial enterprises and provide thermal energy for heating and ventilation systems, hot water supply of buildings and technological production processes. Heating boiler rooms are intended for the same purposes, but serve residential and public buildings. They are divided into separate, interlocked, i.e. adjacent to other buildings, and built into buildings. Recently, more and more often stand-alone enlarged boiler houses are being built with the expectation of serving a group of buildings, a residential quarter, a microdistrict.

The installation of boiler houses built into residential and public buildings is currently allowed only with appropriate justification and coordination with the sanitary supervision authorities.

Low-power boiler houses (individual and small group ones) usually consist of boilers, circulation and make-up pumps and draft devices. Depending on this equipment, the dimensions of the boiler room are mainly determined.

Boilers of medium and high power - 3.5 MW and above - are distinguished by the complexity of the equipment and the composition of service and amenity premises. Space-planning solutions for these boiler houses must meet the requirements of the Sanitary Design Standards industrial enterprises(SI 245-71), SNiP P-M.2-72 and 11-35-76.

1.2 Classification of boiler plants

Boiler plants, depending on the nature of consumers, are divided into energy, production and heating and heating. According to the type of heat carrier produced, they are divided into steam (for generating steam) and hot water (for generating hot water).

Power boiler plants produce steam for steam turbines in thermal power plants. Such boiler houses are equipped, as a rule, with boiler units of large and medium power, which produce steam with increased parameters.

Industrial heating boiler plants (usually steam) produce steam not only for industrial needs, but also for heating, ventilation and hot water supply.

Heating boiler plants (mainly water-heating, but they can also be steam) are designed to service heating systems for industrial and residential premises.

Depending on the scale of heat supply, heating boiler houses are divided into local (individual), group and district.

Local boiler houses are usually equipped with hot water boilers with water heating up to a temperature of not more than 115 ° C or steam boilers with an operating pressure of up to 70 kPa. Such boiler houses are designed to supply heat to one or more buildings.

Group boiler plants provide heat to groups of buildings, residential areas or small neighborhoods. Such boiler houses are equipped with both steam and hot water boilers, as a rule, with higher heat output than boilers for local boiler houses. These boiler houses are usually located in specially constructed separate buildings.

District heating boiler houses are used to supply heat to large residential areas: they are equipped with relatively powerful hot water or steam boilers.

On fig. 1.1 shows a diagram of a boiler plant with steam boilers. The installation consists of a steam boiler 4, which has two drums - upper and lower. The drums are interconnected by three bundles of pipes forming the heating surface of the boiler. When the boiler is operating, the lower drum is filled with water, the upper drum is filled with water in the lower part, and saturated steam in the upper part. In the lower part of the boiler there is a furnace 2 with a mechanical grate for burning solid fuel. When burning liquid or gaseous fuels, nozzles or burners are installed instead of a grate, through which fuel, together with air, is supplied to the furnace. The boiler is limited by brick walls - brickwork.

Rice. 1.1. Scheme of a steam boiler plant

The working process in the boiler room is proceeding in the following way. Fuel from the fuel storage is fed by a conveyor to the bunker, from where it enters the grate of the furnace, where it burns. As a result of fuel combustion, flue gases are formed - hot products of combustion.

Flue gases from the furnace enter the boiler gas ducts, formed by lining and special partitions installed in pipe bundles. When moving, the gases wash the bundles of pipes of the boiler and superheater 3, pass through the economizer 5 and the air heater 6, where they are also cooled due to the transfer of heat to the water entering the boiler and the air supplied to the furnace. Then, the significantly cooled flue gases are removed by means of a smoke exhauster 5 through the chimney 7 into the atmosphere. Flue gases from the boiler can also be discharged without a smoke exhauster under the action of natural draft created by the chimney.

Water from the source of water supply through the supply pipeline is supplied by pump 1 to the water economizer, from where, after heating, it enters the upper drum of the boiler. The filling of the boiler drum with water is controlled by the water-indicating glass installed on the drum.

From the upper drum of the boiler, water descends through pipes into the lower drum, from where it rises again through the left bundle of pipes into the upper drum. In this case, the water evaporates, and the resulting steam is collected in the upper part of the upper drum. Then the steam enters the superheater 3, where it is completely dried due to the heat of the flue gases, and its temperature rises.

From the superheater, steam enters the main steam pipeline and from there to the consumer, and after use it condenses and returns in the form of hot water (condensate) back to the boiler room.

Losses of condensate at the consumer are replenished with water from the water supply system or from other sources of water supply. Before entering the boiler, water is subjected to appropriate treatment.

The air necessary for fuel combustion is taken, as a rule, from the top of the boiler room and is supplied by fan 9 to the air heater, where it is heated and then sent to the furnace. In boiler rooms of low power, air heaters are usually absent, and cold air is supplied to the furnace either by a fan or due to rarefaction in the furnace created by a chimney. Boiler plants are equipped with water treatment devices (not shown in the diagram), instrumentation and appropriate automation equipment, which ensures their uninterrupted and reliable operation.

Hot water boiler plants are designed to produce hot water used for heating, hot water supply and other purposes.

On fig. 1.2 shows a diagram of a district heating boiler house with hot water boilers 1 type PTVM-50 with a heat output of 58 MW. The boilers can run on liquid and gaseous fuels, so they are equipped with 3 burners and nozzles.

The air necessary for combustion is supplied to the furnace by 4 blowers driven by electric motors. Each boiler has 12 burners and the same number of fans.

Water is supplied to the boiler by pumps 5 driven by electric motors. After passing through the heating surface, the water heats up and enters the consumers, where it gives off part of the heat and returns to the boiler with a reduced temperature. Flue gases from the boiler are removed to the atmosphere through pipe 2.

Rice. 1.2. Scheme of a district heating boiler plant with hot water boilers

The layout of the semi-open boiler room: Bottom part boilers (up to about 6 m high) is located in the building, and their upper part is in the open air. Inside the boiler house there are blow fans, pumps, as well as a control panel. A deaerator 6 is installed on the ceiling of the boiler house to remove air from the water.

Boiler plant with steam boilers (Fig. 1.1) has a layout closed type when all the main equipment of the boiler house is located in the building.

This article is devoted to an overview of boiler houses, classification, their characteristics, purpose and other issues one way or another related to the design, construction, as well as the use and operation of boiler houses.

Boiler plants

In the photo only boiler houses built by our specialists

The basis of any boiler house is a boiler or a cascade of boilers. Let's see what boilers are and what functions they perform. I’ll make a reservation right away, here we will talk about industrial boilers used in heating systems for buildings, groups of buildings, various structures, industrial enterprises, large warehouses, etc. Here we will not touch on the topic of small boilers and boiler rooms for heating cottages, private houses, tennis courts, etc. This is a separate, also quite interesting topic, with its subtleties and nuances.

All boilers can be divided into different categories.

So, according to the type of fuel consumed, boilers can be:

• solid fuel,
• liquid fuel,
• electric,
• gas,
• Combined.

Solid fuel boilers are fired with brown and coal, firewood, fuel briquettes, dried briquetted peat. Being the oldest in age, they are still used in traditionally industrial, coal-mining areas. That is, where the use of solid fuels is economically justified, because, for the most part, these boilers require the construction of feeding and grinding devices, ash collectors and many other specific devices and even structures. To not pollute so much environment large capital investments are required. Therefore, despite the low prices for solid fuels, new construction, and even reconstruction, is quite expensive. Therefore scientists different countries now they are looking for ways of more rational and environmentally friendly burning of coal, they are developing new systems of boiler plants, since coal reserves, unlike oil and gas, should be enough for several hundred years. And to the use of coal as fuel, but at a different level, mankind will undoubtedly return.

Liquid fuel boilers consume diesel fuel, fuel oil, other hydrocarbon liquid products. These boilers are widely used in areas where there is no main natural gas, coal, in remote areas of the North, where it is difficult to use other fuels. Such boilers require huge, often heated, fuel tanks, the construction of refractory walls. It is commonly believed that liquid fuels pollute the environment with their emissions, but this is not the case. So when using liquid fuel boilers, well-established manufacturers, and with good adjustment, it is possible to achieve quite acceptable results in terms of harmful emissions into the atmosphere.

Electric boilers consuming electricity can be used where there are enough electricity resources, and the tariff is not so high. Often they are used as a temporary measure, as they can be quickly installed and put into operation. Also for the same reason, apply in emergency situations, or where there are no other (or they are unprofitable) energy resources. One way or another, but their use is limited, although from an environmental point of view, if you do not affect the primary production of electricity, these are the “cleanest” heat producers.

Gas boilers operate on natural gas from a gas main, on bottled natural gas compressed to high pressure, on liquefied gas such as propane-butane, they can operate on "modified" associated gas, on biogas. In the US, there are boilers that run on hydrogen. In Russia and Europe, natural gas is the most demanded fuel in industry, and most importantly, in heating systems for residential buildings, industrial facilities, and various agricultural structures. Leading European companies for the production of gas boilers and burners have perfected their designs to ensure high efficiency (reaches 98%), as well as ergonomics and safety during operation.

This fuel is, in itself, a safe product of combustion. If we neglect the combustion of impurities, for example, sulfur, then the combustion products consist of carbon dioxide and water. True, there is one "but". When burning at high temperatures in the air (and air is not only oxygen, but also other gases, primarily nitrogen), some concentrations of nitrogen oxides NOx are formed, which, with strong deviations from the norm, can lead to acid rain. Therefore, there are always increased requirements both to gas-burning equipment, as well as to the quality of commissioning work.

With well-conducted commissioning, the amount of NOx in the exhaust gases is negligible (no more than 50-60 ppm). And if the combustion temperature of the gas is reduced as much as possible, for example, flameless catalytic combustion is used in special grates, then it is possible to achieve a combustion temperature of no more than 6000C, and a NOx concentration of no more than 20 ppm. And the problem becomes practically solvable. So, if we compare gas with other types of energy resources, excluding electricity (and this is a separate issue), then it is the most environmentally friendly and, probably, the most convenient fuel of all currently used.

Combined boilers are made in such a way that they can consume, after some switching, different combinations fuels, for example, gas-solar oil, gas-fuel oil, gas-diesel oil-solid fuel. The price for this is the complicated design of boilers and burners, as well as a much more complex adjustment of burners. However, boilers with such burners are in demand where it is necessary to reserve emergency fuel (usually light fuel (diesel oil). Housing and communal services of city departments require the use of equipment that runs on gas as well as and on reserve fuel, so that it can be used in case of shortage of main gas for heating the residential sector during severe frosts.

According to the coolant, boilers are divided into

• steam,
• Water heating.

Steam boilers, which recently held a leading position, due to the fact that steam was more widely used in production, are now used much more rarely. They are still used in light, food and some other industries. With new construction or modernization, new steam boilers are now being installed, which are several levels superior to the previous ones both in safety and in productivity, and they are automated in fact. high level.

The cost of such boilers is rather big, therefore they are used only in industry where steam is really needed, for heating housing and communal services - this is not cost-effective.

For heating systems of residential buildings, only old steam boilers that have not exhausted their resource are used, which are replaced year after year with hot water boilers.

There are other reasons for abandoning steam boilers, they are that,

• Firstly, to supply steam as a heat carrier, heating devices specially designed for this purpose must be installed in houses, in which steam condenses and the condensate is obligatory removed. Two, three decades ago, they got out of this situation by installing a high-speed steam-to-water heat exchanger in the boiler room or in the central heating center, in which the steam was condensed, and the water heated by the steam was already going to houses, to conventional heating appliances. In any case, the heat supply system turned out to be more cumbersome than when using hot water boilers.
• Secondly, the boiler room system equipped with steam boilers is more potentially dangerous. High pressures, burning properties of steam, aging of the metal of steam pipelines under high pressure(metal becomes more brittle) - these are the reasons that people think about when choosing a boiler room.
• It is difficult to stop a boiler house in case of an accident. It takes a lot of time.
• Obsolescence at a lower efficiency than a hot water boiler.

Modern hot water boilers provide a high efficiency of up to 95%, the process technology, especially among European companies, has been worked out, one might say, perfected. Boilers operate in normal mode, if necessary, the heating system is easily stopped, since there is no high temperature steam superheated under pressure, like in steam boilers.

All modern boilers and burners completed for them are sufficiently automated. Do not require the constant presence of personnel. In case of any malfunction, for example, gas contamination of the boiler room, carbon monoxide or methane, increasing or decreasing the pressure of the coolant in the system, power outages, etc., the automation system will simply stop the gas supply (i.e. turn off the boiler room) and “call” a specialist (give a signal to the control room) to find out the breakdown. At the same time, the circulation of the coolant will not stop, so that “defrosting” of the system does not threaten. Housing and boiler room together with heating networks will cool down chalky. According to experience, at least 12 hours for a boiler house with a capacity of 4 ... 6 MW. During this time, you can carry out any, even very complex repairs (although you should not bring it to this).

All boiler rooms can be conditionally divided into:

• industrial,
• Heating.

Industrial boilers include boilers that participate in the production cycle of an enterprise, for example, dry, or vice versa, moisten raw materials, create an atmosphere elevated temperatures for the course of any reaction, sterilize and pasteurize products. This entire list is endless. As mentioned above, process steam is often required for industrial purposes. For these purposes, the most modern automated steam boilers have been developed. The value of industrial boiler houses is difficult to exaggerate, as they are necessary in national economy.

Heating includes boiler houses that participate in the heating system of industrial and residential premises.

Heating boilers can be divided into:

• District, which are part of district thermal stations. The power of these boilers is usually tens of megawatts. They heat entire districts, tens, and sometimes hundreds of thousands of people. Such enlarged heat supply schemes have both undeniable merits, such as the concentration in one place of all material and human resources, the integrated management of the entire system, a single emergency service, a single settlement center, etc. But there are also huge drawbacks, the diameters of pipes of heat networks began to reach and exceed a meter, and lines of heating networks - dozens kilometers. Heat losses during the transmission of heat energy became very noticeable, huge expenses for the repair of heating mains, errors in the operation of multi-megawatt equipment became very expensive.
• Offline sources heat supply AIT. Such boiler houses heat a building, a group of buildings, a microdistrict, a quarter. Previously, such boiler houses were called central or quarterly. In Moscow, in the North-West, there is an experimental residential area "Kurkino". There is no district heating from a single heating plant. Here the whole district is divided into microdistricts, about 5...10 multi-storey buildings. Each of these neighborhoods is heated from one small gas boiler. Heating network here are short and small diameters, so heat losses are minimal. That is, the gain in efficiency is obvious.
• Increasingly, on the roofs of multi-storey residential buildings, one can see an individual rooftop boiler room, which provides the house with its own heat. The HOA, operating such a boiler house, saves the residents' money, since there are no heat losses in the networks, except for intra-house ones, while each resident can adjust the microclimate in his apartment with a special thermostat, rather than opening the window, releasing heat to the street, but a "smart" boiler will switch to lower power. But this, despite the convenience, is also a responsibility and the need to participate in self-government processes, for which not all residents are yet ready.

I would also like to note that today the construction of a new boiler house is a very expensive business. Therefore, they try to reduce the cost of the boiler room in any way. This can be done, for example, by reducing the cost of the construction part. So less and less began to make stationary boiler rooms with capital building, with a strong foundation, began to switch to assembly technologies for block-modular buildings, which are simply placed on a flat slab. The second step is that it is much more profitable and faster to install the main and auxiliary heating equipment boiler room in this block-modular building directly at the factory, and on site only connect to the supply lines and install a chimney system. Such a boiler house is called block-modular and may consist of one or several blocks, convenient and passing in size during transportation.

Speaking of chimneys. Previously, the pipes were made of brick, had a large mouth diameter of up to 2.0 m, and were fitted with fastening bandages - clamps over the entire height. Usually several boilers were connected to such a chimney, there were special smoke exhausters that created draft in the chimney. The construction of the pipe was subject to increased requirements for the cleanliness of the inner surface finish and the lining. Such chimneys were introduced and taken out of operation for a long time, because it took a long time to heat up (cool down) the chimney.