The flue gas condensing system makes it possible to recover and recover the large amount of thermal energy contained in the moist flue gas from the boiler, which is usually emitted through a chimney to the atmosphere.

The system of heat recovery/flue gas condensation allows to increase by 6 - 35% (depending on the type of fuel burned and plant parameters) heat supply to consumers or reduce natural gas consumption by 6-35%

Main advantages:

• Fuel economy (natural gas) - the same or increased boiler heat load with less fuel combustion
• Emission reduction - CO2, NOx and SOx (when burning coal or liquid fuels)
• Receiving condensate for the boiler feeding system

Principle of operation:

The heat recovery/flue gas condensation system can be operated in two stages: with or without humidification of the air supplied to the boiler burners. If necessary, a scrubber is installed before the condensation system.

In the condenser, the flue gases are cooled with the return water from the heating network. When the flue gas temperature drops, a large amount of water vapor contained in the flue gas condenses. The thermal energy of vapor condensation is used to heat the heating system return.

Further cooling of the gas and condensation of water vapor occurs in the humidifier. The cooling medium in the humidifier is blast air supplied to the boiler burners. Since the blast air is heated in the humidifier and the warm condensate is injected into the air stream in front of the burners, an additional evaporation process takes place in the flue gas of the boiler.

The blast air supplied to the boiler burners contains an increased amount of thermal energy due to increased temperature and humidity.

This results in an increase in the amount of energy in the outgoing flue gas entering the condenser, which in turn leads to a more efficient use of heat by the district heating system.

In the flue gas condensing plant, condensate is also produced, which, depending on the composition of the flue gas, will be further purified before being fed into the boiler system.

Economic effect.

Comparison of thermal power under the conditions:

1. No condensation
2. Flue gas condensation
3. Condensation together with humidification of the combustion air

The flue gas condensation system allows the existing boiler house to:

• Increase heat generation by 6.8% or
• Reduce gas consumption by 6.8%, as well as increase revenues from the sale of quotas for CO, NO
• The amount of investment is about 1 million euros (for a boiler house with a capacity of 20 MW)
• Payback period 1-2 years.

Savings depending on the temperature of the coolant in the return pipeline:

V.S. Galustov, Doctor of Technical Sciences, Professor, General Director of SE NPO "Polytechnic"
L.A. Rozenberg, engineer, director of UE Yumiran.

Introduction.

With flue gases of various origins, thousands and thousands of Gcal of heat, as well as thousands of tons of gaseous and solid pollutants, and water vapor are emitted into the atmosphere. In this article, we will focus on the problem of heat recovery (we will talk about the purification of gas emissions in the next message). The deepest use of the heat of fuel combustion is carried out in thermal power boilers, for which, in most cases, economizers are provided in their tail section. The flue gas temperature after them is about 130–190°C, i.e. is close to the acid vapor dew point temperature, which is the lower limit in the presence of sulfur compounds in the fuel. When burning natural gas, this limitation is less significant.

Flue gases after various types of furnaces can have a significantly higher temperature (up to 300-500°C and above). In this case, heat recovery (and gas cooling) is simply mandatory, if only to limit thermal pollution of the environment.

Heat recovery units.

Even in the first message, we limited the range of our interests to processes and devices with direct phase contact, however, to complete the picture, we will also recall and evaluate other options. All known heat exchangers can be divided into contact, surface, and devices with an intermediate coolant. The first one will be discussed in more detail below. Surface heat exchangers are traditional heaters that are placed directly in the flue after the furnace (boiler) and have serious drawbacks that limit their use. Firstly, they introduce significant aerodynamic resistance into the gas path and worsen the operation of furnaces (the vacuum decreases) with a design smoke exhauster, and replacing it with a more powerful one may not compensate for the accompanying costs by saving heat. Secondly, the low coefficients of heat transfer from the gas to the surface of the tubes determine the large values ​​of the required contact surface.

Apparatuses with an intermediate heat carrier are of two types: intermittent operation with a solid heat carrier and continuous operation with a liquid one. The first ones are at least two columns filled, for example, with crushed granite (packing). Flue gases pass through one of the columns, giving off heat to the nozzle, heating it to a temperature slightly lower than the temperature of the gases. Then the flue gases are switched to the second column, and the heated medium is supplied to the first (usually air supplied to the same furnace, or air from the air heating system), etc. The disadvantages of such a scheme are obvious (high resistance, bulkiness, temperature instability, etc.), and its application is very limited.

Apparatuses with a liquid intermediate heat carrier (usually water) were called contact heat exchangers with active packing (KTAN), and the authors, after a slight improvement, called them heat exchangers with saturated coolant and condensation (TANTEK). In both cases, the water heated by flue gases then gives off the received heat through the wall of the surface built-in heat exchanger to clean water (for example, heating systems). Compared to heaters, the resistance of such heat exchangers is much lower, and in terms of heat exchange in the flue gases - water system, they are completely similar to the direct-flow spray apparatus of interest to us. However, there are significant differences, which we will discuss below.

The developers of the KTAN and TANTEK apparatuses do not consider in their publications the features of heat transfer in the direct contact of flue gases and water, so we will dwell on them in more detail.

The main processes in the system flue gases - water.

The result of the interaction of heated flue gases (by composition and properties, this is actually humid air) and water (in the form of droplets of one size or another), which we will call a heat-accumulating medium (it can be used as the main or intermediate heat carrier), is determined by a whole range of processes.

Simultaneously with heating, condensation of moisture on the surface of the droplets or evaporation can occur. In fact, there are three options for the mutual direction of heat and moisture flows (heat transfer and mass transfer), which depend on the ratio of phase temperatures and the ratio of partial vapor pressures in the boundary layer (near the droplet) and in the core of the gas flow (Fig. 1a).

In this case, the first (upper) case, when heat and moisture flows are directed from drops to gas, corresponds to evaporative cooling of water; the second (middle) - heating drops with simultaneous evaporation of moisture from their surface; the third (lower) version, according to which heat and moisture are directed from gas to drops, reflects the heating of water with vapor condensation. (It would seem that there should also be a fourth option, when the cooling of droplets and the heating of the gas are accompanied by moisture condensation, but this does not occur in practice.)

All the described processes can be visually represented on Ramzin's diagram of the state of humid air (H-x diagram, Fig. 1b).

Already from what has been said, we can conclude that the third option is most desirable, but in order to understand how to ensure it, it is necessary to recall in addition to what was stated in:

- the amount of water vapor contained in 1 m3 of moist air is called the absolute humidity of the air. Water vapor occupies the entire volume of the mixture, so the absolute humidity of the air is equal to the density of water vapor (under given conditions) pp

- when the air is saturated with steam, there comes a moment when condensation begins, i.e. the maximum possible vapor content in the air at a given temperature is achieved, which corresponds to the density of saturated water vapor pH;

- the ratio of absolute humidity to the maximum possible amount of steam in 1 m3 of air at a given pressure and temperature is called relative humidity f;

- the amount of water vapor in kg per 1 kg of absolutely dry air is called the moisture content of the air x;

- moist air as a heat carrier is characterized by enthalpy / (heat content), which is a function of temperature and moisture content of the air and is equal to the sum of the enthalpies of dry air and water vapor. In the most convenient form for practical application, the formula for calculating enthalpy can be represented

I \u003d (1000 + 1.97. 103x) t + 2493. . 103x J / kg of dry air, where 1000 is the specific heat capacity of dry air, J / kg * deg); 1.97 * 103 - specific heat capacity of steam, J / (kg * deg); 2493*103 is a constant coefficient approximately equal to the enthalpy of steam at 0°C; t is the air temperature, °С;

I = 0.24t + (595 + 0.47t) Xkcal/kg dry air; where 595 is a constant coefficient approximately equal to the enthalpy of steam at 0°C; 0.24 is the specific heat capacity of dry air, kcal/(kgtrad); 0.47 is the heat capacity of steam, kcal/(kgtrad);

- when the air is cooled (in conditions of constant moisture content), the relative humidity will increase until it reaches 100%. The corresponding temperature is called the dew point temperature. Its value is determined solely by the moisture content of the air. On the Ramzin diagram, this is the point of intersection of the vertical line x = const with the line φ = 1.

Air cooling below the dew point is accompanied by moisture condensation, i.e. air drying.

Some confusion is caused by publications that give dew point values ​​for various solid and liquid fuels of the order of 130-150 ° C. It must be borne in mind that this concerns the beginning of the condensation of vapors of sulfuric and sulfurous acids (we denote eetpK), and not water vapor (tp), which we spoke about above. For the latter, the dew point temperature is much lower (40-50°C).

So, three quantities - flow rate, temperature and moisture content (or wet bulb temperature) - fully characterize flue gases as a source of secondary energy resources.

When water comes into contact with hot gases, the liquid is initially heated and vapors condense on the surface of cold drops (corresponds to the 3rd option in Fig. 1a) until the temperature corresponding to the dew point for the gas is reached, i.e. the boundary of the transition to the second regime (variant 3 in Fig. 1a). Further, as the water is heated and the partial pressure of vapor at the surface of the droplets increases, the amount of heat transferred to them due to heat transfer Q1 will decrease, and the amount of heat transferred from droplets to flue gases due to evaporation Q2 will increase. This will continue until equilibrium is reached (Q1 = Q2), when all the heat received by water from the flue gas will be returned to the gas in the form of the heat of evaporation of the liquid. After that, further heating of the liquid is impossible, and it evaporates at a constant temperature. The temperature reached in this case is called the wet bulb temperature tM (in practice, it is defined as the temperature indicated by a thermometer, the bulb of which is covered with a damp cloth, from which moisture evaporates).

Thus, if water with a temperature equal to (or greater than) tM is supplied to the heat exchanger, then adiabatic (at a constant heat content) cooling of gases will be observed and there will be no heat recovery (not counting the negative consequences - loss of water and humidification of gases).

The process becomes more complicated if we take into account that the composition of the droplets is polydisperse (due to the mechanisms of liquid decomposition during spraying). Small droplets instantly reach tM and begin to evaporate, changing the gas parameters towards an increase in moisture content;

heat up and condense moisture. All this occurs simultaneously in the absence of clear boundaries.

It is possible to comprehensively analyze the results of direct contact between drops of a heat-accumulating medium and hot flue gases only on the basis of a mathematical model that takes into account the entire complex of phenomena (simultaneously occurring heat and mass transfer, changes in the parameters of the media, aerodynamic conditions, polydisperse composition of the droplet flow, etc.).

The description of the model and the results of analysis based on it is given in the monograph, which we recommend to the interested reader. Here we note only the main thing.

For most flue gases, the wet bulb temperature is in the range of 45-55°C, i.e. water in the zone of direct contact with flue gases, as noted above, can only be heated to the specified temperature, although with a sufficiently deep heat recovery. Preliminary humidification of gases, as provided for by the TANTEK design, not only does not lead to an increase in the amount of utilized heat, but even to its decrease.

And, finally, it should be borne in mind that when utilizing heat, even from gases that do not contain sulfur compounds, they should not be cooled below 80 ° C (their evacuation to the environment through the flue and chimney is difficult).

Let us explain what has been said with a specific example. Let the flue gases after the boiler in the amount of 5000 kg/h, having a temperature of 130°C and a moisture content of 0.05 kg/kg, contact with a heat recovery medium (water, tH= 15°C). From the H-x diagram we find: tM= 49.5°C; tp= 40°C; I \u003d 64 kcal / kg. Model calculations showed that when gases are cooled to 80°C by a polydisperse flow of droplets with an average diameter of 480 μm, the moisture content actually remains unchanged (evaporation of small droplets is compensated by condensation on large ones), tM becomes equal to 45°C, and heat content I = 50 kcal/kg . Thus, 0.07 Gcal/h of heat is utilized, and the heat storage medium in the amount of 2.5 m3/h is heated from 15 to 45°C.

If we use TANTEK and preliminarily conduct humidification - adiabatic cooling of gases to t-100°C, and then cool to 80°C at X = const, then the final parameters of the gas will be: tM = 48°C; I = 61.5°C. And although the water will heat up a little higher (up to 48 ° C), the amount of heat utilized decreases by 4 times and will be 0.0175 Gcal/h.

Options for organizing heat recovery.

The solution of a specific problem of flue gas heat utilization depends on a number of factors, including the presence of pollutants (determined by the type of fuel burned and the object of flue gas heating), the presence of a heat consumer or directly hot water, etc.

At the first stage, it is necessary to determine the amount of heat that, in principle, can be extracted from the available flue gases, and evaluate the economic feasibility of heat recovery, since the capital costs for it are not proportional to the amount of heat recovered.

If the answer to the first question is yes, then the possibility of using moderately heated water should be assessed (for example, when burning natural gas, send it to prepare make-up water for boilers or heating systems, and if the target product is contaminated with dust particles, use it to prepare the raw mass, for example, in the production of ceramic products etc.). If the water is too polluted, it is possible to provide a two-circuit system or combine heat recovery with flue gas cleaning (to obtain higher (above 45-5 CPC) temperatures or a surface stage).

There are many options for organizing the process of heat recovery. The economic efficiency of the event depends on the choice of the optimal solution.

Literature:

1. Galustov B.C. Heat and Mass Transfer Processes and Apparatuses with Direct Phase Contact in Thermal Power Engineering // Energy and Management.— 2003.— No. 4.

2. Galustov B.C. Direct-flow spraying apparatus in thermal power engineering. - M .: Energoatomizdat, 1989.

3. Sukhanov V.I. and others. Installations for heat recovery and flue gas cleaning of steam and hot water boilers. - M .: AQUA-TERM, July 2001.

4. Planovsky A.N., Ramm V.M., Kagan S.Z. Processes and apparatuses of chemical technology.— M.: Goshimizdat, 1962.—S.736-738.

Description:

Bryansk heating networks, together with the design institute OOO VKTIstroydormash-Proekt, developed, manufactured and implemented in two boiler houses in the city of Bryansk a flue gas heat recovery unit (UUTG) from hot water boilers

Flue gas heat recovery plant

N. F. Sviridov, R. N. Sviridov, Bryansk heating networks,

I. N. Ivukov, B. L. Turk, VKTIstroydormash-Proekt LLC

Bryansk Heat Networks, together with the design institute OOO VKTIstroydormash-Proekt, developed, manufactured and implemented in two boiler houses in the city of Bryansk a flue gas heat recovery unit (UUTG) from hot water boilers.

As a result of this implementation, the following was obtained:

Additional capital investments per 1 Gcal / h of heat received are more than 2 times lower in comparison if a new boiler house was being built, and pay off in approximately 0.6 years;

Due to the fact that the equipment used is extremely easy to maintain and free coolant is used, i.e. flue gas (FG), previously released into the atmosphere, the cost of 1 Gcal of heat is 8–10 times lower than the cost of heat generated by boiler houses;

Boiler efficiency increased by 10%.

Thus, all the costs in March 2002 prices for the introduction of the first UUTG with a capacity of 1 Gcal of heat per hour amounted to 830 thousand rubles, and the expected savings per year will be 1.5 million rubles.

Such high technical and economic indicators are understandable.

There is an opinion that the efficiency of the best domestic boilers with a thermal power of 0.5 MW and above reaches 93%. In fact, it does not exceed 83%, and here's why.

Distinguish between lower and higher calorific value of fuel. The lower calorific value is less than the higher one by the amount of heat that is spent on the evaporation of water formed during the combustion of the fuel, as well as the moisture contained in it. An example for the cheapest fuel is natural gas: DGs formed during its combustion contain water vapor, which occupies up to 19% in their volume; the highest calorific value of its combustion exceeds the lowest by approximately 10%.

To increase the efficiency of the chimneys through which the DGs are emitted into the atmosphere, it is necessary that the water vapor in the DGs does not begin to condense in the chimneys at the lowest ambient temperatures.

The UUTG projects revived and improved long-forgotten technical solutions aimed at utilizing heat from DGs.

UUTG contains contact and plate heat exchangers with two independent circuits of circulating and waste water.

The device and operation of the UUTG are clear from the diagram shown in the figure and the description of its positions.

In a contact heat exchanger, DG and atomized circulating water move in vertical countercurrent, i.e. DG and water are in direct contact with each other. To maintain a uniform spray of recycled water, nozzles and a special ceramic nozzle are used.

Heated circulating water, pumped in its own water circuit by an independent pump, gives off the heat acquired in the contact heat exchanger to the waste water in the plate heat exchanger.

For the required cooling of circulating water, only cold tap water should be used, which, after heating in the UUTG, is brought to the standard temperature in the boilers of existing boiler houses and is further used for hot water supply to housing.

In the contact heat exchanger, the cooled DGs additionally pass through the drop eliminator and, having eventually lost more than 70% of moisture in the form of water vapor condensate, they are connected to a part of the hot DGs (10–20% of the DG volume leaving the boiler), directed immediately from the boiler to the chimney, thus forming a mixture of DG with low moisture content and with a temperature sufficient for the passage of the chimney without condensing the rest of the water vapor.

The volume of circulating water is continuously increasing due to the condensate of water vapor in the DG. The resulting surplus is automatically drained through a valve with an electromechanical drive and can be used with preparation as additional water in the heating system of the boiler room. The specific consumption of drained water per 1 Gcal of recovered heat is about 1.2 tons. The condensate drain is controlled by level gauges B and H.

The described method and equipment for heat recovery of diesel generators are able to work with dust-free fuel combustion products that have an unlimited maximum temperature. At the same time, the higher the temperature of the flue gas, the higher the temperature will be heated to the consumption water. Moreover, in this case it is possible to partially use the recycled water for heating heating water. Considering that the contact heat exchanger simultaneously works as a wet dust trap, it is possible to practically utilize the heat of dusty DGs by purifying circulating water from dust by known methods before supplying it to the plate heat exchanger. It is possible to neutralize recycled water contaminated with chemical compounds. Therefore, the described UUTG can be used to work with DGs involved in technological processes during smelting (for example, open-hearth furnaces, glass melting furnaces), during calcination (for example, brick, ceramics), during heating (ingots before rolling), etc.

Unfortunately, in Russia there are no incentives to engage in energy conservation.

At present, the temperature of flue gases behind the boiler is taken not lower than 120-130 ° C for two reasons: to prevent condensation of water vapor on flues, flues and chimneys and to increase natural draft, which reduces the pressure of the smoke exhauster. In this case, the heat of the exhaust gases and the latent heat of vaporization of water vapor can be usefully used. The use of the heat of flue gases and the latent heat of vaporization of water vapor is called the method of deep utilization of the heat of flue gases. Currently, there are various technologies for implementing this method, tested in the Russian Federation and widely used abroad. The method of deep utilization of flue gas heat makes it possible to increase the efficiency of a fuel-consuming plant by 2–3%, which corresponds to a reduction in fuel consumption by 4–5 kg of fuel equivalent. per 1 Gcal of generated heat. When implementing this method, there are technical difficulties and limitations associated mainly with the complexity of calculating the heat and mass transfer process with deep utilization of the heat of the flue gases and the need to automate the process, however, these difficulties can be solved with the current level of technology.

For the widespread implementation of this method, it is necessary to develop guidelines for the calculation and installation of flue gas deep heat recovery systems and the adoption of legal acts prohibiting the commissioning of fuel-using natural gas installations without the use of flue gas deep heat recovery.

1. Formulation of the problem according to the considered method (technology) of increasing energy efficiency; a forecast of overspending of energy resources, or a description of other possible consequences on a national scale while maintaining the status quo

At present, the temperature of flue gases behind the boiler is taken not lower than 120-130 ° C for two reasons: to prevent condensation of water vapor on flues, flues and chimneys and to increase natural draft, which reduces the pressure of the smoke exhauster. In this case, the temperature of the outgoing flue gases directly affects the value of q2 - heat loss with the outgoing gases, one of the main components of the heat balance of the boiler. For example, a decrease in the temperature of flue gases by 40°C when the boiler is operating on natural gas and an excess air ratio of 1.2 increases the gross efficiency of the boiler by 1.9%. This does not take into account the latent heat of vaporization of combustion products. To date, the vast majority of hot water and steam boiler units in our country that burn natural gas are not equipped with installations that use the latent heat of vaporization of water vapor. This heat is lost along with the exhaust gases.

2. Availability of methods, methods, technologies, etc. to solve the given problem

Currently, methods of deep exhaust heat recovery (VER) are used by using recuperative, mixing, combined apparatuses operating with various methods of using the heat contained in exhaust gases. At the same time, these technologies are used in most of the boilers commissioned abroad that burn natural gas and biomass.

3. A brief description of the proposed method, its novelty and awareness of it, the availability of development programs; result in mass implementation nationwide

The most commonly used method of deep flue gas heat recovery is that the combustion products of natural gas after the boiler (or after the water economizer) with a temperature of 130-150°C are divided into two streams. Approximately 70-80% of the gases are sent through the main flue and enter the surface-type condensing heat exchanger, the rest of the gases are sent to the bypass flue. In the heat exchanger, the combustion products are cooled to 40-50°C, while part of the water vapor is condensed, which makes it possible to use both the physical heat of the flue gases and the latent heat of condensation of a part of the water vapor contained in them. The cooled combustion products after the droplet separator are mixed with non-cooled combustion products passing through the bypass flue and at a temperature of 65-70°C they are removed by a smoke exhauster through the chimney into the atmosphere. As a heated medium in the heat exchanger, source water for the needs of chemical water treatment or air, which then enters combustion, can be used. To intensify heat exchange in the heat exchanger, it is possible to supply steam from the atmospheric deaerator into the main flue. It should also be noted the possibility of using condensed demineralized water vapor as source water. The result of the introduction of this method is an increase in the gross efficiency of the boiler by 2-3%, taking into account the use of the latent heat of vaporization of water vapor.

4. Forecast of the effectiveness of the method in the future, taking into account:
- rising prices for energy resources;
- the growth of the welfare of the population;
- introduction of new environmental requirements;
- other factors.

This method improves the efficiency of natural gas combustion and reduces emissions of nitrogen oxides into the atmosphere due to their dissolution in condensing water vapor.

5. List of groups of subscribers and objects where this technology can be used with maximum efficiency; the need for additional research to expand the list

This method may be used in steam and hot water boilers using natural and liquefied gas, biofuel as fuel. To expand the list of objects where this method can be used, it is necessary to study the processes of heat and mass transfer of combustion products of fuel oil, light diesel fuel and various grades of coal.

6. Identify the reasons why the proposed energy efficient technologies are not applied on a mass scale; outline an action plan to remove existing barriers

The mass application of this method in the Russian Federation is usually not carried out for three reasons:

• Lack of awareness about the method;
• The presence of technical limitations and difficulties in implementing the method;
• Lack of funding.

7. Availability of technical and other restrictions on the application of the method on various objects; in the absence of information on possible limitations, it is necessary to determine them by testing

The technical limitations and difficulties in implementing the method include:

• The complexity of calculating the process of utilization of wet gases, since the heat transfer process is accompanied by mass transfer processes;
• The need to maintain the set values ​​of temperature and humidity of the flue gases, in order to avoid condensation of vapors in the gas ducts and chimney;
• The need to avoid freezing of heat exchange surfaces when heating cold gases;
• At the same time, it is necessary to test gas ducts and chimneys treated with modern anti-corrosion coatings in order to reduce the restrictions on temperature and humidity of flue gases leaving after the heat recovery plant.

8. The need for R&D and additional testing; themes and objectives of the work

The need for R&D and additional testing is given in paragraphs 5 and 7.

9. Existing incentives, coercion, incentives for the implementation of the proposed method and the need to improve them

There are no existing measures to encourage and coerce the introduction of this method. Interest in reducing fuel consumption and emissions of nitrogen oxides into the atmosphere may stimulate the introduction of this method.

10. The need to develop new or change existing laws and regulations

It is necessary to develop guidelines for the calculation and installation of deep flue gas heat recovery systems. Perhaps, it is necessary to adopt legal acts prohibiting the commissioning of fuel-using installations on natural gas without the use of deep flue gas heat recovery.

11. Availability of decrees, rules, instructions, standards, requirements, prohibitive measures and other documents regulating the use of this method and mandatory for execution; the need to make changes to them or the need to change the very principles of the formation of these documents; the presence of pre-existing regulatory documents, regulations and the need for their restoration

There are no questions regarding the application of this method in the existing regulatory framework.

12. Availability of implemented pilot projects, analysis of their real effectiveness, identified shortcomings and proposals for improving the technology, taking into account the accumulated experience

There is no data on the large-scale implementation of this method in the Russian Federation, there is experience of implementation at the CHPPs of RAO UES and, as mentioned above, a lot of experience has been accumulated in deep utilization of flue gases abroad. The All-Russian Thermal Engineering Institute carried out design studies of installations for deep utilization of heat from combustion products for hot water boilers PTVM (KVGM). The disadvantages of this method and suggestions for improvement are given in paragraph 7.

13. The possibility of influencing other processes during the mass introduction of this technology (changes in the environmental situation, possible impact on human health, increased reliability of energy supply, changes in daily or seasonal loading schedules for power equipment, changes in economic indicators of energy generation and transmission, etc.)

The mass introduction of this method will reduce fuel consumption by 4-5 kg ​​of fuel equivalent. per Gcal of generated heat and will affect the environment by reducing emissions of nitrogen oxides.

14. Availability and sufficiency of production capacities in Russia and other countries for the mass implementation of the method

The specialized production facilities in the Russian Federation are able to ensure the implementation of this method, but not in a monoblock version; when using foreign technologies, a monoblock version is possible.

15. The need for special training of qualified personnel for the operation of the implemented technology and the development of production

To implement this method, existing profile training of specialists is necessary. It is possible to organize specialized seminars on the implementation of this method.

16. Suggested methods of implementation:
1) commercial financing (with cost recovery);
2) a competition for the implementation of investment projects developed as a result of work on energy planning for the development of a region, city, settlement;
3) budget financing for efficient energy-saving projects with long payback periods;
4) introduction of prohibitions and mandatory requirements for the use, supervision of their observance;
5) other offers.

Suggested implementation methods are:

• budget financing;
• attraction of investments (payback period 5-7 years);
• introduction of requirements for the commissioning of new fuel-consuming installations.

In order to add description of energy saving technology to the Catalog, fill out the questionnaire and send it to marked "to Catalog".

I propose to consider activities for the disposal of flue gases. Flue gases are abundant in any village and city. The main part of the smoke producers are steam and hot water boilers and internal combustion engines. I will not consider the flue gases of engines in this idea (although they are also suitable in composition), but I will dwell on the flue gases of boiler houses in more detail.

The easiest way is to use the smoke of gas boilers (industrial or private houses), this is the cleanest type of flue gas, which contains the minimum amount of harmful impurities. You can also use the smoke of boilers burning coal or liquid fuel, but in this case you will have to clean the flue gases from impurities (this is not so difficult, but still additional costs).

The main components of flue gas are nitrogen, carbon dioxide and water vapour. Water vapor is of no value and can be easily removed from the flue gas by contacting the gas with a cool surface. The remaining components already have a price.

Gaseous nitrogen is used in fire fighting, for the transportation and storage of flammable and explosive media, as a shielding gas to protect easily oxidized substances and materials from oxidation, to prevent corrosion of tanks, to purge pipelines and containers, to create inert media in grain silos. Nitrogen protection prevents the growth of bacteria, is used to clean environments from insects and microbes. In the food industry, a nitrogen atmosphere is often used as a means of increasing the shelf life of perishable products. Gaseous nitrogen is widely used to obtain liquid nitrogen from it.

To obtain nitrogen, it is sufficient to separate water vapor and carbon dioxide from the flue gas. As for the next component of smoke - carbon dioxide (CO2, carbon dioxide, carbon dioxide), the range of its application is even greater and its price is much higher.

I suggest getting more information about it. Typically, carbon dioxide is stored in 40-liter cylinders painted black with a yellow inscription "carbon dioxide". A more correct name for CO2 is “carbon dioxide”, but everyone is already used to the name “carbon dioxide”, it has been assigned to CO2 and therefore the inscription “carbon dioxide” on the cylinders is still preserved. Carbon dioxide is found in cylinders in liquid form. Carbon dioxide is odorless, non-toxic, non-flammable and non-explosive. It is a substance that occurs naturally in the human body. In the air exhaled by a person, it usually contains 4.5%. Carbon dioxide is mainly used in carbonation and sale in bottling drinks, it is used as a shielding gas during welding using semi-automatic welding machines, it is used to increase the yield (2 times) of agricultural crops in greenhouses by increasing the concentration of CO2 in the air and increasing ( 4-6 times when saturated with carbon dioxide water) for the production of microalgae during their artificial cultivation, for the preservation and improvement of the quality of feed and products, for the production of dry ice and its use in cryoblasting plants (cleaning surfaces from contamination) and for obtaining low temperatures during storage and food transportation, etc.

Carbon dioxide is a commodity in demand everywhere and the need for it is constantly increasing. In home and small businesses, carbon dioxide can be obtained by extracting it from flue gas in low-capacity carbon dioxide plants. It is not difficult for persons related to technology to make such an installation on their own. Subject to the norms of the technological process, the quality of the resulting carbon dioxide meets all the requirements of GOST 8050-85.
Carbon dioxide can be obtained both from the flue gases of boiler houses (or heating boilers of private households) and by the method of special combustion of fuel in the installation itself.

Now the economic side of things. The unit can operate on any type of fuel. When fuel is burned (especially to produce carbon dioxide), the following amount of CO2 is released:
natural gas (methane) - 1.9 kg of CO2 from the combustion of 1 cu. m of gas;
hard coal, different deposits - 2.1-2.7 kg of CO2 from the combustion of 1 kg of fuel;
propane, butane, diesel fuel, fuel oil - 3.0 kg CO2 from burning 1 kg of fuel.

It will not be possible to fully extract all the carbon dioxide released, and up to 90% (95% extraction can be achieved) is quite possible. The standard filling of a 40-liter cylinder is 24-25 kg, so you can independently calculate the specific fuel consumption to obtain one carbon dioxide cylinder.

It is not so big, for example, in the case of obtaining carbon dioxide from the combustion of natural gas, it is enough to burn 15 m3 of gas.

According to the highest tariff (Moscow) it is 60 rubles. per 40 liter. carbon dioxide bottle. In the case of CO2 extraction from boiler flue gases, the cost of carbon dioxide production is reduced, as fuel costs are reduced and the profit from the installation is increased. The unit can operate around the clock, in automatic mode with minimal involvement of a person in the process of obtaining carbon dioxide. The productivity of the plant depends on the amount of CO2 contained in the flue gas, the design of the plant, and can reach 25 carbon dioxide cylinders per day or more.

The price of 1 cylinder of carbon dioxide in most regions of Russia exceeds 500 rubles (December 2008). Monthly revenue from the sale of carbon dioxide in this case reaches: 500 rubles per ball. x 25 points/day x 30 days = 375,000 rubles. The heat released during combustion can be used simultaneously for space heating, and in this case there will be no irrational use of fuel. At the same time, it should be borne in mind that the environmental situation at the place of extraction of carbon dioxide from flue gases is only improving, as CO2 emissions into the atmosphere are decreasing.

The method of extracting carbon dioxide from flue gases obtained from the combustion of wood waste (waste from logging and wood processing, carpentry shops, etc.) also recommends itself well. In this case, the same CO2 plant is supplemented with a wood gas generator (manufactured or self-manufactured) to produce wood gas. Wood waste (chocks, wood chips, shavings, sawdust, etc.) is poured into the gas generator hopper 1-2 times a day, otherwise the plant operates in the same mode as in the above.
The output of carbon dioxide from 1 ton of wood waste is 66 cylinders. The revenue from one ton of waste is (at the price of a cylinder of carbon dioxide 500 rubles): 500 rubles per ball. x 66 ball. = 33,000 rubles.

With an average amount of wood waste from one wood processing shop of 0.5 tons of waste per day, the proceeds from the sale of carbon dioxide can reach 500 thousand rubles. per month, and in the case of the import of waste from other woodworking and carpentry shops, the revenue becomes even greater.

It is also possible to obtain carbon dioxide from the burning of car tires, which is also only for the benefit of our ecology.

In the case of the production of carbon dioxide in an amount greater than it can be consumed by the local market, the produced carbon dioxide can be independently used for other activities, as well as processed into other chemicals and reagents (for example, using a simple technology into environmentally friendly carbon-containing fertilizers, dough baking powder and etc.) up to the production of motor gasoline from carbon dioxide.