Regulations on the organization of work in the Ministry of Industry and Energy of the Russian Federation to approve standards for creating fuel reserves at thermal power plants and boiler houses. II. Methodology for calculating standards for creating fuel reserves

Natural gas, as a fuel for power plants, is available in almost all industrial zones of Russian cities. In 2010, the gasification level in Russia averaged 62%. In cities, the level of gasification has increased over last years by 6%, to 67%. In rural areas, the level of gasification increased by 8% and today stands at 44%.

The construction of thermal power plants operating on natural gas requires relatively small investments - in comparison with power plants operating on other types of fuel, such as coal, uranium, and hydrogen.

The electrical efficiency of a modern gas power plant reaches 55–60%, while that of a coal power plant is only 32–34%. At the same time, capital costs for 1 MW/hour of installed capacity of a gas thermal power plant are only 50% of a coal-fired power plant, 20% of a nuclear power plant, and 15% of a wind power plant.

Gas is economically more effective than other types of fuel and alternative energy sources.

Construction of a gas power plant takes only 14–18 months. A modern coal-fired power plant will take 54–58 months to build. It will take at least 56–60 months to build a nuclear power plant (NPP).

Gas is the most affordable and economically feasible solution for electricity producers and consumers who are counting money.

Alternative energy sources or gas power plants - who will win in the near future?

It is likely that someday alternative energy sources will replace fossil fuels, but this will not happen anytime soon. For example, in order for wind energy to account for 10% of global energy consumption, from 1 million to 1.5 million wind turbines are needed. Just to house these wind turbines would require an area of ​​550,000 square meters. km. This is equal to the area of ​​the Khanty-Mansiysk Autonomous Okrug or the largest European country - France.

The problem is not only in space: alternative sources are not the most The best decision from a business point of view. Alternative energy sources are not yet economically viable. Most economical efficient look Today's fuel is gas. Gas allows you to obtain cheaper electricity compared to alternative energy.

Gas and ecology

Gas is a significantly cleaner fuel than any other hydrocarbon energy carrier. When gas is burned, it emits less carbon dioxide compared to other traditional sources such as coal. This, accordingly, has a much smaller negative impact on the environment. A modern gas power plant has virtually no harmful emissions into the atmosphere and in this sense its emissions are similar to those of conventional gas stoves. The misconception of many people is the misconception about supposedly absolutely clean alternative energy sources. Wind, geothermal and hydroelectric power plants also cause damage to the environment, sometimes quite a lot.

For thermal power plants, the transition from coal to gas contributes to a sharp reduction in carbon dioxide emissions into the atmosphere. Gas has a higher calorific value than coal. In order to get the same amount of energy, you just need to burn more coal. Gas power plants are more efficient in terms of efficiency: with the same amount of heat released during combustion, a gas thermal power plant produces more electricity.

As a result, replacing coal-fired power with gas-fired thermal power plants reduces CO 2 emissions by 50–70%.

Gas is an environmentally adequate fuel.

Gas reserves - will there be enough for our children and grandchildren?

You can often read that gas reserves are exhaustible, but this is not true. There will be enough gas not only for our lifetime. The gas will not run out during the lifetime of our children or their grandchildren. According to the International Energy Agency, at current rates of gas production, already discovered reserves of this fuel will be enough for 130 years of production. We are talking about gas reserves, the extraction of which is possible and cost-effective with the existing level of technology. The volume of gas reserves is estimated at 400 trillion. cubic meters

Recoverable reserves of unconventional gas (such as tight gas, shale gas and coalbed methane) amount to at least another 380 trillion. cubic meters As technology develops, their extraction becomes more and more feasible. Thus, the already discovered gas reserves will last approximately 250 years. At the same time, exploration methods are constantly being improved, which makes it possible to increase reserves. To date, the United States, the world's largest energy consumer, is provided with reserves of unconventional gas for 100 years to come. The second largest consumer, China, also has similar gas reserves.

Gas is a solution to the problem of energy shortages in the 21st century.

Violation by owners or other legal owners of thermal power plants producing electrical and thermal energy for consumers, their officials, of fuel reserve standards, the procedure for the creation and use of fuel reserves by thermal power plants -

shall entail the imposition of an administrative fine on officials in the amount of thirty thousand to fifty thousand rubles or disqualification for a period of eighteen months to three years; for legal entities - in the amount of the cost of the subject of the administrative offense at the time of completion or suppression of the administrative offense.

Note. For the purposes of this article, the cost of the subject of an administrative offense means the cost of fuel, the reserves of which are not sufficient to comply with the fuel reserve standard at a thermal power plant. In this case, the specified cost of fuel is determined based on the price of such fuel, taken into account by the federal executive body, the executive body of the subject Russian Federation in the field of state regulation of prices (tariffs) when setting prices (tariffs) for electrical energy (power) and (or) thermal energy.

If the specified prices (tariffs) are not subject to government regulation, the price of fuel is set based on the market price of this type of fuel, determined in accordance with official sources of information on market prices and (or) stock exchange quotations.

Order
Ministry of Industry and Energy
Russian Federation
dated October 4, 2005 No. 269

On the organization of work in the Ministry of Industry and Energy of the Russian Federation to approve standards for creating fuel reserves at thermal power plants and boiler houses

In order to implement the Decree of the Government of the Russian Federation of June 16, 2004 No. 284 “On approval of the Regulations on the Ministry of Industry and Energy of the Russian Federation” (Collected Legislation of the Russian Federation, 2004, No. 25, Art. 2566; No. 38, Art. 3803; 2005 , No. 5, Art. 390) I order:

1. Approve the attached Regulations on the organization in the Ministry of Industry and Energy of the Russian Federation of work to approve standards for creating fuel reserves at thermal power plants and boiler houses.

2. Approve the attached Procedure for calculating and justifying standards for creating fuel reserves at thermal power plants and boiler houses.

3. I reserve control over the implementation of this Order.

Acting Minister

REGULATIONS On the organization of work in the Ministry of Industry and Energy of the Russian Federation to approve standards for creating fuel reserves at thermal power plants and boiler houses

1. These Regulations determine the procedure for reviewing and approving standards for creating fuel reserves at thermal power plants and boiler houses (hereinafter referred to as standards).

2. In accordance with these Regulations, standards for the creation of fuel reserves (coal, peat, fuel oil, diesel fuel) for the billing period at thermal power plants (hereinafter referred to as TPPs) and boiler houses that have regular fuel supplies are subject to approval. For power plants operating on gas fuel, reserve fuel standards are subject to approval.

3. To approve the standards, the organization, before June 1 of the year preceding the regulation period, submits to the Ministry of Industry and Energy of Russia an application with supporting materials in accordance with paragraph 8 of these Regulations.

4. Materials on the justification of standards on the day of their receipt by the Ministry of Industry and Energy of Russia are subject to mandatory registration in the register of documents according to standards.

Each application received by the Ministry of Industry and Energy of Russia is assigned a number, the time, day, month and year of receipt is indicated, and a stamp of the Ministry of Industry and Energy of Russia is affixed.

5. After registration, materials on justification of standards are submitted for consideration to the Department of Fuel and Energy Complex of the Ministry of Industry and Energy of Russia.

Documents containing commercial and official secrets must be marked accordingly.

6. The procedure for approving standards is carried out by considering relevant cases.

7. To organize the work on approving standards, a Commission for Approval of Standards (hereinafter referred to as the Commission) is formed, and an authorized person in the case is determined from among the employees of the Department of the Fuel and Energy Complex.

8. For each application of the organization, a case is opened on the approval of standards, in which the following materials are filed:

1) a written application for approval of standards, to which are attached copies of constituent and registration documents, a certificate from the tax authority on registration.

2) documents justifying the values ​​of the standards submitted for approval for the billing period, in accordance with the list and requirements of the Procedure for calculating and justifying the standards for creating fuel reserves at thermal power plants and boiler houses (hereinafter referred to as the Procedure).

The file contains an inventory of the documents stored in it, in which for each document the following is indicated: its serial number in the file, date of receipt, name and details, number of sheets, surname, initials and signature of the employee of the Ministry of Industry and Energy of Russia who entered the document into the file.

9. When a large number of documents are accumulated in one case, it is allowed to divide the case into volumes. In this case, on title page The volume serial number is also indicated. The list of documents must correspond to the documents actually contained in this volume.

10. In the file on approval of standards, entries are made in the following columns:

1) in the column “Document number” the serial number of the received document is entered;

2) in the column “Date of reception” the date of receipt (receipt) of documents is entered (including upon additional request);

3) in the column “Received documents” the name of the received document and the number of sheets are indicated;

4) in the column “Documents accepted” the surname and initials of the authorized person in the case of approval of standards are indicated, and his signature is affixed;

5) in the column “Decision made” information about the result of consideration of the submitted documents is indicated.

11. The authorized person in the case, within a week from the moment of registration, checks the correctness of the materials according to the standards: completeness; availability of the specified applications; availability of identifying details (signature, stamp, registration number, surname and telephone number of the applicant), analyzes the submitted materials to determine their compliance with the requirements specified in the Procedure, and sends to the organization a notice of the opening of the case indicating the position, surname, first name and patronymic of the person, appointed by the commissioner in the case, as well as the date of consideration of the case for approval of standards.

12. The Ministry of Industry and Energy of Russia organizes an examination of materials substantiating the values ​​of the standards submitted for approval.

13. The duration of the examination is determined by the Commission depending on the labor intensity of the expert work and the volume of submitted materials, but should not exceed 30 days.

14. Based on the results of the examination, a conclusion is drawn up, which is attached to the file on the approval of standards. Expert opinions are submitted no later than two weeks before the date of consideration by the Commission of the case on approval of standards.

15. Expert opinions, in addition to general motivated conclusions and recommendations, must contain:

1) assessment of the reliability of the data provided in proposals for approval of standards;

2) analysis of the compliance of the calculation of standards and the form for submitting proposals with the approved regulatory and methodological documents on the issues of approval of standards;

3) calculation materials and summary analytical tables;

4) supporting documents;

5) other information.

16. The organization, 2 weeks before the consideration of the case on approval of standards, is sent a notice of the date, time and place of the meeting of the Commission and a draft protocol of the Commission on approval of standards.

17. At its meetings, the commission considers materials submitted by organizations on the approval of standards, expert opinions and makes decisions on the issue of approval of standards.

18. If the presented materials, in terms of their volume, content and validity, do not allow us to draw a conclusion on the approval of the standards, the Commission decides on the need for additional elaboration of the materials.

19. Within 5 days from the date of registration of the protocol, an order of the Ministry of Industry and Energy of Russia is issued to approve the standards, including:

1) the value of the approved standards;

2) date of entry into force of the standards;

3) validity periods of standards.

An extract from the order with the attachment of approved standards, certified by the seal of the Ministry of Industry and Energy of Russia, is sent to the organization.

20. The order of the Ministry of Industry and Energy of Russia on the approval of standards is published on the website of the Ministry of Industry and Energy of the Russian Federation.

Approved

By order of the Ministry of Industry and Energy of Russia

ORDER

CALCULATION AND JUSTIFICATION OF STANDARDS FOR CREATION OF FUEL RESERVES AT THERMAL POWER PLANTS AND BOILER HOUSES

I. The procedure for forming technological fuel reserves at power plants and boiler houses of the electric power industry

1. The procedure for calculating and justifying the standards for creating fuel reserves at thermal power plants and boiler houses establishes the basic requirements for the standardization of technological fuel reserves (coal, fuel oil, peat, diesel fuel) in the production of electrical and thermal energy.

2. The standard for creating technological fuel reserves at thermal power plants and boiler houses is the general standard fuel reserve (hereinafter - OGST) and is determined by the sum of the volumes of the irreducible standard fuel stock (hereinafter - NNST) and the standard operational reserve of main or reserve fuels (hereinafter - NEZT) .

3. NNZT ensures the operation of the power plant and boiler house in “survival” mode with a minimum design electrical and thermal load under the conditions of the coldest month of the year and a composition of equipment that allows maintaining positive temperatures in the main building, auxiliary buildings and structures.

4. NEZT is necessary for reliable and stable operation of power plants and boiler houses and ensures the planned production of electrical and thermal energy.

5. Regulation of actions with NZT at thermal power plants and boiler houses is necessary in order to prevent the consequences of a complete shutdown of power plants or boiler houses and associated long-term restrictions and disconnections of consumers.

6. Regulation of NEZT at power plants and boiler houses, in addition to ensuring reliable and stable operation, is also necessary in order to control the creation of fuel reserves when preparing power plants and boiler houses of all purposes for operation in the autumn-winter period (hereinafter referred to as the AWP).

7. At power plants operating in a unified power system, the NNZT takes into account the need to supply power to non-disconnected consumers powered by power plant feeders and without backup power from the unified power system.

8. Electricity consumption for the power plant’s own needs, as well as for power supply to consumers, with the exception of those that cannot be disconnected, is not taken into account in the NNCT calculation, since power in this case for the period the power plant reaches NNCT can be provided from a unified power system.

9. NNZT for power plants operating in isolation from the unified energy system includes a reserve of fuel for electrical and thermal own needs, as well as for heat and electricity supply to non-disconnected consumers.

10. NNZT is established for a period of 3 years and is subject to adjustment in cases of changes in the composition of equipment, fuel structure, as well as the load of non-disconnected consumers of electrical and thermal energy that do not have power from other sources.

11. NNZT for electric power plants is determined in agreement with the organization performing dispatch functions.

12. Calculation of NNZT is carried out for each type of fuel separately.

13. NNZT for power plants and boiler houses burning coal and fuel oil must ensure the operation of thermal power plants (hereinafter - TPP) in survival mode for seven days, and for thermal power plants burning gas - three days.

14. The fuel included in the NEZT, accumulated by October 1 - the beginning of the winter period, is included in the consumption for the generation of electrical and thermal energy during the winter period in accordance with the energy-fuel balances for each power plant and boiler house.

15. The annual NEZT calculation is made for each power plant and boiler house that burns or has solid or liquid fuel (coal, fuel oil, peat, diesel fuel) as a backup. Calculations are made on the target date - October 1 of the planned year, which characterizes preparation for work in the occupational labor market from October 1 to April 1 of the following year.

16. Calculations of NNZT and NEZT are made in accordance with Chapter III of this Procedure.

17. NNZT and NEZT for associations of power plants and boiler houses are determined as the total volumes, respectively, for all power plants and boiler houses included in the association.

18. Calculations of standards for creating fuel reserves for the target date (October 1 of the planned year) before their submission to the Ministry of Industry and Energy of Russia, as a rule, are considered:

For power plants and boiler houses of the electric power industry by the relevant associations of power plants and (or) boiler houses;

For organizations of housing and communal services (hereinafter - housing and communal services) by the relevant structural divisions of executive authorities of the constituent entities of the Russian Federation.

19. All results of calculations and justification of accepted coefficients for determining fuel reserve standards at thermal power plants and boiler houses are presented in the form of an explanatory note on paper (bookleted in a separate book) and in electronic form: explanatory note - in Word format, calculations and necessary for calculations initial information is in Excel format.

II. Features of the procedure for calculating standards for heat sources municipalities

20. The annual requirement of NEZT for each heat source is determined by type of fuel in accordance with the existing regulatory characteristics of the equipment.

22. NEZT and AZT are determined by the sum of the values ​​of all heating (industrial heating) boiler houses included in the municipality.

23. ONZT and its components (excluding the state reserve) for each heat source or groups of heat sources of municipalities are determined according to Table 1 (for fuel consumption up to 150 t/h) and Table 2 (for fuel consumption over 150 t/h). Daily consumption fuel is determined for the coldest month.

24. Standards for groups of heat sources in municipalities are determined taking into account the availability of basic fuel storage warehouses.

25. The minimum fuel reserves in the warehouses of heat supply organizations of housing and communal services are: coal - 45, fuel oil - 30-day requirement.

26. The development of standards is carried out taking into account schedules, routes, methods of fuel delivery and its storage at heat source warehouses or base warehouses in the amount of standard fuel reserves before the start of the heating season.

Table 1

Volume of CVD for fuel consumption up to 150 t/h

table 2

Volume of fuel consumption for fuel consumption over 150 t/h

___________________

* For power plants that do not have a second independent source of gas supply.

III. Methodology for calculating standards for creating fuel reserves at thermal power plants and boiler houses in the electric power industry

27. Calculation of NNZT is carried out for power plants and boiler houses on the basis of regulatory and technical documents on fuel use.

28. Calculation of NNZT for power plants and boiler houses is drawn up in the form of an explanatory note. The calculation results are drawn up separately, signed by the heads of these power plants or boiler houses (Appendix 1 to this Procedure) and agreed upon by the head of the association that includes these power plants or boiler houses.

29. The explanatory note to the calculation of NZT includes the following sections:

1) List of non-switchable external consumers of thermal and electrical energy and data on minimum permissible loads. The thermal load of power plants and boiler houses is not taken into account, which, according to the conditions of heating networks, can be temporarily transferred to other power plants and boiler houses;

2) Justification of the technological scheme and composition of equipment that ensures the operation of power plants and boiler houses in “survival” mode;

3) Calculation of the minimum required thermal power for the own needs of power plants and boiler houses, as well as electric power for the own needs of power plants operating in isolation from the Unified Energy System of Russia.

30. The annual calculation of NEZT for the planned year (from January 1 of the planned year to January 1 of the next year) is carried out as of the control date of October 1 for individual power plants and boiler houses. The results of NEZT calculations are drawn up together with the results of the ONZT calculation according to the sample in accordance with Appendix 2 to this Procedure. An explanatory note is attached to the results of NEZT calculations.

31. According to the features of the scheme for performing the annual calculation of NEZT, power plants and boiler houses are divided into three categories:

Standard (standard calculation scheme);

With limited (seasonal) periods for fuel delivery;

Those who had a critical level of fuel reserves in the previous year (less than 60% of the total fuel reserves as of October 1).

32. The calculation basis for a standard group of power plants and boiler houses is taken as the average daily consumption of coal, fuel oil, peat, diesel fuel at power plants or boiler houses in January and April of the planned year, necessary to fulfill the production program for the production of electrical and thermal energy of the planned year, taking into account the average increase coefficient average daily fuel consumption in January and April for the last three years before the planned one. The calculation is performed using the formula:

NEZT = Vpr · Kr · Tper · Ksr, thousand tons,

where Vpr is the average daily fuel consumption to implement the production program in January and similarly in April of the planned year, thousand tons;

Kr - coefficient of change in average daily fuel consumption in January and similarly in April for the three years preceding the planned year, is determined by the formula:

B1, B2, B3 - actual average daily fuel consumption in January and similarly in April for the first, second and third years preceding the planned year;

Ksr - coefficient of possible delivery disruption (takes into account delivery conditions created depending on the situation on the fuel market, relationships with suppliers, transportation conditions and other factors that increase transportation time), is accepted in the range of 1.5 - 2.5;

Tper is the weighted average time for transporting fuel from different suppliers, determined by the formula:

where Tper1, Tper2, ..., Tpern - time of transportation of fuel from different suppliers, days;

Vmes1, Vmes2, ..., Vmesn - estimated volumes of fuel supplies from various suppliers for January and April of the planned year.

NEZTokt. = NEZTyanv. + (NEZTyanv. - NEZTapr.), thousand tons.

34. In cases of separate combustion (in queues or boiler plants) of coal from different deposits or non-interchangeable deposits, NEZT is determined for each deposit. The total NEZT for a power plant or boiler house is determined by summation.

35. NEZT as of October 1 for associations of power plants and (or) boiler houses or individual power plants and boiler houses with limited delivery periods must ensure their operation from the end of one delivery period to the beginning of the next similar period with a safety factor K3 = 1.2, taking into account possible under realistic conditions, a shift in the start time of fuel supplies to areas with limited delivery times.

36. NEZT for combining power plants and (or) boiler houses or individual power plants and boiler houses that had a critical level of fuel reserves on October 1 in the previous operational period is increased by an accident rate coefficient (Kav) equal to 1.2 of the calculated values.

37. NRT is calculated by the sum of NRT and NERT. The calculation results are drawn up separately according to the sample in accordance with Appendix 2 to these Regulations, signed by the heads of power plants and boiler houses and agreed upon by the head of the association that includes these power plants and (or) boiler houses.

38. In exceptional cases, it is possible to adjust fuel reserve standards in the event of significant changes in the program for generating electrical and thermal energy or a change in the type of fuel. The procedure for changing standards is similar to the initial approval under these Regulations.

Appendix No. 1

standards for creating fuel reserves
at thermal power plants
and boiler houses
(sample)

Irreducible standard fuel reserve (MRF)

power plant (boiler house) ______________________

(Name)

1. Coal total _______ thousand tons

incl. by deposits*** _______

2. Fuel oil _______ thousand tons

Power plant manager

(boiler room) Full name (signature)

department name,

_____________________

** To be agreed upon for power plants.

*** For separate combustion.

Appendix No. 2

to the Procedure for calculation and justification

standards for creating fuel reserves

at thermal power plants

and boiler houses

(sample)

AGREED*:

Head of the association

power plants and (or) boiler houses

______________________________

initials, surname

"__" ___________________ 200_

Total standard fuel reserve (TSF) as of the target date of the planned year of the power plant (boiler house) ___________________

(Name)

Power plant manager

(boiler room) Full name (signature)

Performer: Full name, position,

department name,

tel. city, local, E-mail

____________________

*Agreed upon the entry of a power plant or boiler house into the association.

Information about the first part of the technological cycle of a thermal power plant is systematized and summarized: preparation various types fuel for combustion, organization of the combustion process, production of superheated steam in boiler plants various designs. The features of the operation of steam boilers at different types organic fuel. Taking into account the increasing importance of environmental protection issues, the authors, using the results of their own research and the achievements of domestic and foreign power engineers, talk in detail about the methods and designs of devices designed to protect the atmosphere from toxic and greenhouse gases, as well as ash particles emitted into the atmosphere with smoke boiler gases. The manual is intended for students of energy specialties at technical universities, engineering and technical personnel of engineering companies and thermal power plants, as well as students of advanced training courses for heating engineers.

* * *

The given introductory fragment of the book Thermal power plant boilers and atmospheric protection (V. R. Kotler, 2008) provided by our book partner - the company liters.

Chapter 2. Organic fuel and features of its use in thermal power plants

2.1. Composition and main characteristics of organic fuel

The primary source of energy used in thermal power plants is fossil fuel of organic origin. The combustible substances included in the fuel are carbon C, hydrogen H and sulfur S (with the exception of a small part of the sulfur contained in the mineral mass of the fuel - sulfate sulfur). In addition to flammable substances, the fuel contains oxygen O (supports combustion, but does not emit heat) and nitrogen N (an inert gas that does not participate in combustion reactions). Oxygen and nitrogen are sometimes referred to as internal fuel ballast, in contrast to external ballast, which includes ash and moisture.

Ash (denoted by the letter “A”) is the mineral part of the fuel, including oxides of silicon, iron, aluminum, as well as salts of alkali and alkaline earth metals.

Fuel moisture (W) is divided into external and hygroscopic. When solid fuel is stored for a long time in a dry place, it loses external moisture and becomes “air-dry”.

Thus, if a certain amount of fuel is taken as 100%, then we can write:

C r + H r + O r + N r + S l r + A r + W r = 100%. (2.1)

The index “r” in this equation means that we are talking about the working mass of fuel received at the power plant (abroad they usually say not “working”, but “as receive”, that is, “received” fuel).

By excluding all moisture from the working composition, you can get:

C d + H d + O d + N d + S l d + A d = 100%. (2.2)

The index “d” in this equation stands for “dry”, that is, “by dry weight”.

C daf + H daf + N daf + O daf + S l daf = 100%. (2.3)

The “daf” index in this equation denotes fuel – “dry ash free”, that is, “dry and free of ash”.

Sulfur with the “l” symbol included in the above equations, firstly, does not include sulfur that is part of the ash, and, secondly, consists of two parts: organic sulfur and pyrite sulfur (Fe 2 S), which is present in some brands of coal in noticeable quantities.

Therefore, we can also consider the organic mass of fuel, which does not contain pyrite sulfur:

C o + H o + O o + N o + S o = 100%. (2.4)

To recalculate the fuel composition, volatile yield and calorific value from one mass of fuel to another, it is necessary to use the conversion factors given in Table. 2.1.

Some peculiarities when recalculating fuel characteristics arise when using shale with a high carbonate content. If for conventional fuels the combustible mass is the difference of 100 – W r – A r, then when the carbonate content is more than 2%, it is necessary to calculate the combustible mass using a different formula:

100−W r −A correct r −(CO 2) K,

where A ispr is the ash content without taking into account sulfates formed during the decomposition of carbonates and adjusted for the combustion of pyrite sulfur, that is

A correct r = A r − (1−W r /100),

where S, Sst and Sk are the sulfur content in laboratory ash, sulfate sulfur in fuel and pyrite sulfur, respectively.

The combustible elements of fuel, as already noted, are carbon, hydrogen and sulfur. Upon complete combustion with the theoretically required amount of oxidizer, these components release different amounts of heat:

C + O 2 = CO 2 − 8130 kcal/kg (34.04 MJ/kg);

2H 2 + O 2 = 2H 2 O − 29,100 kcal/kg (121.8 MJ/kg);

S + O 2 = SO 2 − 2600 kcal/kg (10.88 MJ/kg).

It should be taken into account that carbon makes up the majority of the working mass of the fuel: in solid fuel its share is 50–75% (depending on the age of the coal), and in fuel oil – 83–85%. There is less hydrogen in the fuel, but it has a very high calorific value. If the products of its combustion are condensed (that is, not the lower, but the higher heat of combustion is taken into account), the released heat will not even be 121.8, but 144.4 MJ/kg.

Sulfur is distinguished by its low heat of combustion, and its quantity is usually small. Consequently, sulfur is not of significant value as a combustible element, but the problems associated with the presence of SO 2 in combustion products are very significant.

Table 2.1 Conversion factors for fuel characteristics

All of the above applies mainly to solid and liquid fuels. Gas, in contrast, is a mechanical mixture of several components. In natural gas from most fields, the main component is methane - CH 4, the amount of which ranges from 85 to 96%. In addition to methane, natural gas usually contains heavier hydrocarbons: ethane C 2 H 6, propane C 3 H 8, butane C 4 H 10, etc. Gas from some fields, in addition to hydrocarbons, also contains other flammable components: hydrogen H 2 and carbon monoxide CO. The non-flammable components of the gas include nitrogen N2 and carbon dioxide CO2.

The main characteristic of any type of organic fuel is its calorific value, that is, the amount of heat released during complete combustion of a unit of mass (for solid and liquid fuels) or unit of volume (for gas). Most often used in calculations lower calorific value(Q i r) is the amount of heat generated by the combustion of 1 kg of coal or fuel oil, and by the combustion of gaseous fuel - 1 m 3 of this gas. It is assumed that the combustion products remain in a gaseous state. Sometimes another thermal characteristic is used - higher calorific value(Q s r), but at the same time in the text it is necessary to clarify that we are talking specifically about Q s r (or HHV - higher heating value, unlike LНV – lower heating value - lower calorific value). The higher calorific value is always greater than the lower calorific value, since it takes into account the additional amount of heat released during condensation of water vapor and cooling of all combustion products to the original temperature.

Conversion of the lower calorific value to the higher one (and vice versa) is performed according to the following relationship:

Q i r = Q s r − 6(W r + 9Н r), kcal/kg (2.5)

Q i r = Q s r − 25.12 (W r + 9H r), kJ/kg. (2.5 a)

It is more convenient to consider other characteristics of fuels that differ in their state of aggregation separately for solid, liquid and gaseous fuels.

2.2. Solid fuel

Solid fuel includes primarily various coals (anthracite, bituminous and brown coals), as well as peat, shale and some types of waste (both industrial and municipal solid waste - MSW). This type of fuel also includes one of the renewable energy sources - biofuel, that is, wood, waste from logging, wood processing, pulp and paper and agricultural production.

The predominant type of fuel for thermal power plants is various grades of coal. In Russia, the division of coals into brown (the youngest), hard and anthracite (old coal with the maximum degree of coalification) has been firmly established.

Brown coals are divided according to maximum moisture capacity (based on ash-free mass W af max) into 3 groups: 1B (W af max > 50%), 2B (30 ≤ W af max ≤ 50) and ZB (W af max< 30 %). Бурые угли отличают high output volatile (V daf > 40%), uncaked coke residue and high hygroscopicity. These coals contain less (compared to hard coals) carbon and more oxygen. When dried in air, brown coals lose mechanical strength and crack. Their disadvantage is their increased tendency to spontaneous combustion during storage in a warehouse.

The classification of hard coals is based on the amount of volatiles per combustible mass, that is, V daf, %. If we leave aside coking coals, which are used mainly in metallurgical production, then all thermal coals can be arranged according to the degree of reduction in V daf: D - long-flame; DG – long-flame gas; G – gas (groups 1G and 2G); low-caking (groups 1CC, 2СС and ЗСС); skinny (groups 1T and 2T). Lean coal of the 1st group has V daf greater than 12%, and 2T - from 8 to 12%. Anthracites (groups 1A, 2A and 3A) close this series. All of them have a volatile yield per combustible mass of less than 8%, but groups 1–3 are distinguished by different volumetric yields of volatile substances.

The above classification does not take into account coals that were subjected to oxidation under natural conditions during the formation of coal deposits. Oxidized coals are characterized by a reduced higher calorific value of dry and ash-free mass (Q s daf), as well as a loss of caking ability. There is oxidation group I (reduction of Qs daf by 10%) and group II (reduction of Qs daf by 25%). For example, long-flame coal from the Tallinn deposit (Kuzbass) has a higher calorific value Q s daf = 31.82 MJ/kg. Oxidized coal from the same deposit DROC-I (long-flame, ordinary, oxidized group I) - up to 27.42 MJ/kg, and even more oxidized coal - DROC-II - only 25.04 MJ/kg.

Another important characteristic of hard coals is the size of the pieces. According to this indicator, coal received at the power plant is divided into the following classes:

plate (P - from 100 to 200 or 300 mm);

large (K – 50–100 mm);

walnut (O – 25–50 mm);

small (M – 13–25 mm);

seed (C – 6–13 mm);

piece (W – 0–6 mm);

ordinary (P – 0–200 or 300 mm).

The upper limit of 300 mm applies only to coal mines, that is, to enterprises with open-pit mining.

Sometimes on thermal power plants Coal does not come directly from the mining enterprise, but after washing plants. When enriching coal using wet and dry methods, the following enrichment products are distinguished: low-ash concentrate, high-ash middling product, screenings of small classes, sludge, as well as rock and “tailings” removed to the dump. Taking this into account, it is possible, based on the marking of coal supplied to thermal power plants, to present some characteristics of the fuel, which are very important both for the reliability of fuel supply within the thermal power plant and for combustion in the boiler shop. For example, GSSH is gas coal with the sizes “seed” and “piece”, and GROCII is also gas coal, but “ordinary”, of the 2nd oxidation group.

The characteristics of the mineral part play a significant role in the organization of the combustion process. Conventionally, the mineral part of coal can be divided into three groups:

– minerals brought into the fuel layer as a result of geological transformations during its formation;

– minerals of rocks adjacent to the fuel layer, included in the fuel during its extraction;

– minerals associated with the organic part of the fuel or formed during its decomposition during the process of coal formation.

The last group of minerals is called internal ash; it is evenly distributed throughout the organic mass of the fuel. The first group of minerals, depending on the uniformity of their distribution throughout the fuel, can be a source of both internal and external ash. The second group of minerals belongs to external ash.

Another one important detail: the amount of ash obtained from complete combustion of coal is not equal to the amount of mineral impurities contained in coal. The fact is that the mineral part includes clay minerals, micas, carbonates, sulfates and a number of other substances. When clay minerals and mica are heated in a furnace, water of crystallization is first lost (up to 500–600 °C), then the original crystal lattice is destroyed and secondary minerals (mullite, spinel, etc.) are formed. With a further increase in temperature (above 1100 °C), melting begins. Even earlier, in the temperature range of 400–900 °C, carbonates decompose and very refractory oxides are formed. At temperatures of 700–800 °C, pyrite completely burns out in an oxidizing environment. All these processes during fuel combustion lead to a significant change in the composition and mass of mineral impurities. Thus, it is more correct to consider that ash is a solid reaction product of the mineral part of the fuel, formed during the combustion of this fuel.

Numerous studies have shown that when burning hard coals, the mineral mass is usually greater than the ash content, and for low-ash brown coals it is less.

For overall assessment chemical properties of ash, the concepts of “acidic” and “basic” composition of slag were introduced. The behavior of ash in the furnace is largely determined by the ratio of acidic to basic oxides:

Taking this into account, the expression of coal ash in Donbass, most of the Kuznetsk, Podmoskovny, Ekibastuz and some other basins is classified as acidic. Coals of the Kansk-Achinsk basin, peat, shale have ash, which is one of the main (K<1,0). Состав золы оказывает большое влияние на шлакующие свойства твердых видов топлива.

2.3. Gaseous fuel

In the conditions of the Russian Federation, gaseous fuel is primarily natural gas, since Russia accounts for almost a third of all proven natural gas reserves. As already noted, gaseous fuel is a mixture of flammable and non-flammable gases containing small amounts of impurities in the form of water vapor and dust. In addition to natural gas, associated and industrial gases can be supplied to power plants: blast furnace gas, coke oven gas, and synthesis gas.

The heat of combustion of individual gases and their mass density are given in table. 2.2.

Table 2.2. Heat of combustion and density of gases

*Density values ​​are given at 0°C and 101.3 kPa.

The main part of natural gas is methane, the share of which in different fields ranges from 84 to 98%. Natural gas contains significantly less heavier saturated and unsaturated hydrocarbons. There are deposits with a noticeable content of toxic and corrosive hydrogen sulfide H 2 S. In Russia, these include, for example, the Orenburg and Astrakhan deposits. The use of such gas in power plants is possible only after it has been purified at gas processing plants.

Associated (oil field) gases consist of methane and other components. These gases contain significantly less CH 4, but the amount of heavy hydrocarbons is already tens of percent. The quantity and quality of associated gas depend on the composition of the crude oil and its stabilization at the production site (only stabilized oil is considered prepared for further transportation via pipelines or tankers).

The average characteristics of associated gases from some fields of the Russian Federation are given in Table. 2.3.

Table 2.3. Composition and density of associated gases

Table 2.4. Composition and density of industrial gases

In addition to natural and associated gases, various artificial gases are sometimes used in industry. At metallurgical industry enterprises (blast furnace production and coke ovens) a large amount of low-calorie blast furnace gas (Q i r = 4.0÷5.0 MJ/m 3) and medium-calorie coke oven gas (Q i r = 17÷19 MJ/m 3) is formed, containing H 2, CH 4, CO and other flammable gaseous components (Table 2.4). Before use in boilers, blast furnace and coke oven gas must be cleaned of dust.

In some countries that are not as rich in natural gas as Russia, there is an entire industry dedicated to the production of generator gases, often called synthesis gases. Methods have been developed and equipment has been created to obtain fuel convenient for everyday use by gasifying solid organic fuels: coal, shale, peat, wood. When using ordinary air as an oxidizer, a low-calorie gas (3÷5 MJ/m 3) is obtained, and gasification with oxygen blast allows one to obtain a medium-calorie gas with Q i r = 16÷17 MJ/m 3. Such gas, unlike low-calorie gas, can be used not only at the point of production, but also transported over a certain distance. The composition of the generator gas is determined by the source fuel and its gasification technology.

However, in the conditions of Russian reality, with relatively low prices for natural gas, all types of generator gas turn out to be uncompetitive in comparison with natural gas. However, in some cases (in the absence of gas pipelines near the facility or the need to dispose of production waste containing organic substances), it is practiced to install gasifiers with air or steam-air blast to produce a gas mixture containing H 2, CO and a small amount of hydrocarbons, which makes it possible to provide gaseous fuel heating boilers with automated burners and high efficiency.

In the second half of the last century, the production of LNG - liquefied natural gas - was established on an industrial scale. This is actually a new type of fuel, which in the first and last stages of its existence is a gas, but during transportation and storage behaves like liquid fuel (thus providing a wide market for sale in vast territories where it is impossible or impractical to run a gas pipeline). LNG is obtained by liquefying natural gas by cooling it to a temperature below – 160 °C. After regasification at the point of consumption, LNG does not lose the properties characteristic of conventional natural gas. At a pressure of 0.6 MPa, which is the operating pressure during transportation and storage of LNG, its density is 385 kg/m 3 . It is clear that at this temperature LNG must be stored and transported in special (cryogenic) containers. The cost of such installations is quite high, but the price of liquefied natural gas is significantly lower than the cost of a similar product - liquefied hydrocarbon gas, better known as a propane-butane mixture.

The raw material for the production of propane-butane mixtures, which are currently widely used only in the residential sector, is mainly associated gas from oil production. Another source of liquefied gas is oil refineries (refineries), which receive crude oil containing liquefied petroleum gases. During the distillation process, they are captured, and their yield is 2–3% of the volume of processed oil. The calorific value of this fuel and its other characteristics depend on the ratio between the butane and propane content.

2.4. Liquid fuel

Liquid fuel is usually a product of crude oil refining (although some countries have developed the technology to produce liquid fuel from coal, shale or other organic substances). Crude oil is a mixture of organic compounds, as well as some sulfur and nitrogen compounds, paraffins and resins. After processing crude oil at refineries, light fuels are obtained: gasoline, kerosene and diesel fuel. These types of fuel are used mainly in transport, in the domestic sector and in internal combustion engines of various industrial enterprises.

Then the refinery produces heating oils, which are heavy cracking residues or mixtures of cracking residues with straight distillation fuel oils. In addition to high viscosity and positive pour point, fuel oils allow a higher content of mechanical impurities, sulfur and water. Heating oils are supplied to thermal power plants and large boilers of industrial boiler houses. At the same time, most of the mineral impurities contained in the original oil are concentrated in the fuel oil.

In accordance with Russian standards, fuel oil grades 40 and 100 are supplied to power plants. The grade in this case is determined by the maximum viscosity of the fuel oil at a temperature of 80 °C. For fuel oil grade 40 it should not exceed 8.0 degrees of conventional viscosity (°VU), and for fuel oil grade 100 - 15.5 °VU When heating fuel oil, the viscosity decreases to a level that ensures stable transport of fuel oil through pipelines and fine atomization in mechanical injectors (Fig. 2.1).

Rice. 2.1. Viscosity-temperature diagram for liquid fuel

Based on sulfur content, fuel oils are divided into low-sulfur (S r ≤0.5%), sulfur (up to 2.0% sulfur) and high-sulfur (up to 3.5% sulfur). The level of sulfur content depends mainly on the sulfur content in the original oil: during its processing, from 70 to 90% of sulfur compounds go into fuel oil, thereby creating serious difficulties for the operating personnel of thermal power plants.

Among other characteristics of fuel oil, ash content, moisture content and density of fuel oil are also significant.

Ash content, as in the case of sulfur content, depends on the content of mineral impurities in the original oil. During its processing, these impurities are concentrated mainly in fuel oil. Nevertheless, the ash residue when burning fuel oil is so small that ash removal of flue gases in fuel oil boilers is, as a rule, not required. A special feature of fuel oil ash is the presence of vanadium in it. In terms of vanadium pentoxide V 2 O 5, this component, which is of great value for industry, can reach 50% when burning high-sulfur fuel oils.

When fuel oil is burned, part of the components of its ash sublimes and then condenses on convective heating surfaces. Solid or molten ash particles, as well as soot and coke particles, are deposited on these primary deposits, creating durable contaminants that adhere to the pipes. Difficult-to-remove deposits containing oxides of vanadium, nickel, iron and sodium impair heat transfer, disrupt the temperature regime and increase the aerodynamic resistance of convective heating surfaces. On heating surfaces with a metal temperature below the dew point, a film of sulfuric acid is formed, on which solid particles of ash and coke are also deposited.

The moisture content of fuel oil shipped to the consumer, as a rule, does not exceed 1.5–2%. But in the process of draining fuel oil from tanks and storing it in fuel oil tanks, the moisture content of the fuel oil increases due to steam, which is used to maintain the desired temperature (for more details, see Chapter 3).

The density of fuel oil is usually estimated by the ratio of the actual density to the density of water at a temperature of 20 °C. As the temperature increases, the relative density of fuel oil decreases and can be calculated using the formula

where ρ t and ρ 20 are the relative densities of fuel oil at the actual temperature t and at 20 °C, β is the coefficient of volumetric expansion when the temperature of the fuel oil increases by 1 °C. For most fuel oils β = (5.1÷5.3)·10 -4.

Two more characteristics of fuel oil are of interest when operating a fuel oil facility: pour point and flash point. The first is the temperature at which the fuel oil thickens so much that in a test tube tilted at 45°, the surface of the fuel oil remains motionless for 1 minute. For fuel oil grade 40, the maximum pour point is +10 °C, and for fuel oil grade 100, with a high content of paraffins, the pour point rises to 25 °C.

Flash point is the temperature at which fuel oil vapor mixed with air ignites upon contact with an open flame. For different brands of fuel oil, the flash point varies over a wide range. Fuel oils that do not contain paraffins have a flash point of 135 to 234 °C, and the flash point of paraffinic fuel oils is close to 60 °C. When choosing a fuel oil heating scheme, the flash point should be taken into account in order to prevent a fire hazard.