M. A. Taimarov, A. V. Simakov

RESULTS OF MODERNIZATION AND UPGRADE TESTS

THERMAL OUTPUT OF THE BOILER TGM-84B

Key words: steam boiler, tests, thermal power, nominal steam capacity, gas-falling openings.

It was experimentally obtained in the work that the design of the TGM-84B boiler makes it possible to increase its steam output by 6.04% and bring it to 447 t/h by increasing the diameter of the gas supply holes of the second row on the central gas supply pipe.

Keywords: the Steam caldron, test, heat power, nominal capacity, gas giving holes.

In work experimentally is obtained, that the construction of the boiler TGM-84B allows to increase it Potency at 6.04 % and to finish it up to 447 t/h by magnification of a diameter Gas pipe of orifices of the second number on central gas pipe.

Introduction

The TGM-84B boiler was designed and manufactured 10 years earlier than the TGM-96B boiler, when the Taganrog Boiler Plant did not have much practical and design experience in the design, manufacture and operation of high-capacity boilers. In this regard, a significant reserve of the area of ​​heat-receiving screen heating surfaces was made in which, as all the experience of operating TGM-84B boilers showed, there is no need. The performance of the burners on the TGM-84B boilers also decreased due to the smaller diameter of the gas outlets. According to the first factory drawing of the Taganrog Boiler Plant, the second row gas outlets in the burners are provided with a diameter of 25 mm, and later, based on operating experience, to increase the heat density of the furnaces, this diameter of the second row gas outlets was increased to 27 mm. However, there is still a margin for increasing the diameter of the gas outlets of the burners in order to increase the steam output of the TGM-84B boilers.

Relevance and statement of the research problem

In the short term for 5 ... .10 years, the need for heat and electricity will increase sharply. The growth in energy consumption is associated, on the one hand, with the use of foreign technologies for the deep processing of oil, gas, wood, metallurgy products directly on the territory of Russia, and, on the other hand, with the retirement and decrease in capacity due to the physical deterioration of the existing fleet of heat and power generating equipment. The consumption of thermal energy for heating purposes is increasing.

There are two ways to quickly meet the growing demand for energy resources:

1. Commissioning of new heat and power generating equipment.

2. Modernization and reconstruction of existing operational equipment.

The first direction requires large investments.

In the second direction of increasing the capacity of heat and power generating equipment, the costs are associated with the amount of necessary reconstruction and superstructure to increase capacity. On average, when using the second direction of increasing the capacity of heat and power generating equipment, the costs are 8 times cheaper than commissioning new capacities.

Technical and design capabilities of the solution for increasing the power of the boiler TGM-84 B

A design feature of the TGM-84B boiler is the presence of a two-light screen.

The two-light screen provides more intensive cooling of flue gases than in the gas-oil boiler TGM-9bB, which is similar in performance and does not have a two-light screen. The dimensions of the boiler furnaces TGM-9bB and TGM-84B are almost the same. The designs, except for the presence of a two-light screen in the TGM-84B boiler, are also the same. The nominal steam output of the TGM-84B boiler is 420 t/h, and for the TGM-9bB boiler the nominal steam output is 480 t/h. The TGM-9b boiler has 4 burners in two tiers. The TGM-84B boiler has 6 burners in 2 tiers, but these burners are less powerful than in the TGM-9bB boiler.

The main comparative technical characteristics of the boilers TGM-84B and TGM-9bB are given in table 1.

Table I - Comparative technical characteristics of boilers TGM-84B and TGM-96B

Name of indicators TGM-84B TGM-96B

Steam capacity, t/h 420 480

Furnace volume, m 16x6.2x23 16x1.5x23

Dual Light Screen Yes No

Rated heat output of the burner when burning gas, MW 50.2 88.9

Number of burners, pcs. b 4

Total thermal power of burners, MW 301.2 355.6

Gas consumption, m3/h 33500 36800

Nominal gas pressure in front of burners at gas temperature (t = - 0.32 0.32

4 °С), kg/cm2

Air pressure in front of the burner, kg/m2 180 180

Required air consumption for blowing at rated steam 3/ load, thousand m3/hour 345.2 394.5

Required performance of smoke exhausters at nominal steam 3 / 399.5 456.6

load, thousand m / hour

Passport nominal total capacity of 2 blowers VDN-26-U, thousand m3/hour 506 506

Passport nominal total capacity of 2 smoke exhausters D-21.5x2U, thousand m3/hour 640 640

From Table. 1 shows that the required steam load of 480 t/h in terms of air flow is provided by two VDN-26-U fans with a margin of 22%, and in terms of removal of combustion products by two smoke exhausters D-21.5x2U with a margin of 29%.

Technical and design solutions for increasing the thermal power of the TGM-84B boiler

At the Department of Boiler Installations of KSPEU, work was done to increase the thermal power of the TGM-84B boiler st. No. 10 NchTPP. Thermal-hydraulic calculation was carried out

burners with a central gas supply, aerodynamic and thermal calculations were performed with an increase in the diameter of the gas supply holes.

On the TGM-84B boiler with station No. 10, on burners No. 1,2,3,4 of the first (lower) tier and No. 5.6 of the second tier, 6 of the existing 12 gas outlets 2- th row from a diameter of 027 mm to a diameter of 029 mm. Falling flows, flame temperature and other operating parameters of boiler No. 10 were measured (Table 2). The unit heat output of the burners increased by 6.09% and amounted to 332.28 MW instead of 301.2 MW before reaming. Steam production increased by 6.04% and amounted to 447 t/h instead of 420 t/h before reaming.

Table 2 - Comparison of indicators of the boiler TGM-84B st. No. 10 NchCHP before and after reconstruction of the burner

Indicators of the boiler TGM-84B No. 10 NchTPP Hole diameter 02? Hole diameter 029

Thermal power of one burner, MW 50.2 55.58

Furnace heat output, MW 301.2 332.28

The increase in the thermal power of the furnace,% - 6.09

Boiler steam capacity, t/h 420 441

Increase in steam production, % - 6.04

Calculations and testing of modernized boilers showed no separation of the gas jet from the gas supply holes at low steam loads.

1. Increasing the diameter of the gas supply holes of the 2nd row from 27 to 29 mm on the burners does not cause gas flow disruption at low loads.

2. Modernization of the TGM-84B boiler by increasing the cross-sectional area of ​​the gas supply

openings from 0.205 m to 0.218 m made it possible to increase the nominal steam capacity from 420 t/h to 447 t/h during gas combustion.

Literature

1. Taimarov, M.A. Boilers of TPPs of high power and supercritical Part 1: study guide / M.A. Taimarov, V.M. Taimarov. Kazan: Kazan. state energy un-t, 2009. - 152 p.

2. Taimarov, M.A. Burner devices / M.A. Taimarov, V.M. Taimarov. - Kazan: Kazan. state energy un-t, 2007. - 147 p.

3. Taimarov, M.A. Laboratory workshop on the course "Boiler plants and steam generators" / M.A. Taimarov. - Kazan: Kazan. state energy un-t, 2004. - 107 p.

© M. A. Taimarov - Dr. Sci. sciences, prof., head. cafe boiler plants and steam generators of KSPEU, [email protected]; A. V. Simakov - Ph.D. the same department.

The TGM-84 boiler unit is designed according to the U-shaped layout and consists of a combustion chamber, which is an ascending gas duct, and a lowering convective shaft, divided into 2 gas ducts. Transitional horizontal flue between the furnace and the convective shaft is practically absent. A screen superheater is located in the upper part of the furnace and in the turning chamber. In the convective shaft, divided into 2 gas ducts, a horizontal superheater and a water economizer are placed in series (along the gases). Behind the water economizer there is a rotary chamber with ash receiving bins.

Two regenerative air heaters connected in parallel are installed behind the convection shaft.

The combustion chamber has the usual prismatic shape with dimensions between the axes of the pipes 6016 * 14080 mm and is divided by a two-light water screen into two semi-furnaces. The side and rear walls of the combustion chamber are shielded with evaporator pipes with a diameter of 60 * 6 mm (steel-20) with a pitch of 64 mm. The side screens in the lower part have slopes towards the middle in the lower part at an angle of 15 to the horizontal and form a “cold” floor.

The two-light screen also consists of pipes with a diameter of 60 * 6 mm with a pitch of 64 mm and has windows formed by pipe routing to equalize the pressure in the semi-furnaces. The screen system is suspended from the metal structures of the ceiling with the help of rods and has the ability to freely fall down during thermal expansion.

The ceiling of the combustion chamber is made horizontal and shielded by pipes of the ceiling superheater.

A combustion chamber equipped with 18 oil burners, which are located on the front wall in three tiers. The boiler is equipped with a drum with an internal diameter of 1800 mm. The length of the cylindrical part is 16200 mm. Separation is organized in the boiler drum, steam is washed with feed water.

Schematic diagram of superheaters

The superheater of the TGM-84 boiler is radiative-convective in nature of heat perception and consists of the following main 3 parts: radiative, screen or semi-radiative and convective.

The radiation part consists of a wall and ceiling superheater.

The semi-radiation superheater consists of 60 standardized screens. Convective superheater of horizontal type consists of 2 parts placed in 2 gas ducts of the downcomer above the water economizer.

A wall-mounted superheater is installed on the front wall of the combustion chamber, made in the form of six transportable blocks of pipes with a diameter of 42 * 55 (steel 12 * 1MF).

The outlet chamber of the ceiling p / p consists of 2 collectors welded together, forming a common chamber, one for each semi-furnace. The output chamber of the combustion p / p is one and consists of 6 collectors welded together.

The inlet and outlet chambers of the screen superheater are located one above the other and are made of pipes with a diameter of 133*13 mm.

The convective superheater is made according to the Z-shaped scheme, i.e. steam enters from the front wall. Each p / p consists of 4 single-pass coils.

Steam superheat control devices include a condensing unit and injection desuperheaters. Injection desuperheaters are installed in front of the screen superheaters in the cut of the screens and in the cut of the convective superheater. When working on gas, all desuperheaters work, when working on fuel oil, only the one installed in the section of the convective p / p.

The steel coiled water economizer consists of 2 parts placed in the left and right gas ducts of the downward convective shaft.

Each part of the economizer consists of 4 height packages. Each package contains two blocks, each block contains 56 or 54 four-way coils made of pipes with a diameter of 25 * 3.5 mm (steel20). The coils are located parallel to the front of the boiler in a checkerboard pattern with a pitch of 80 mm. The economizer collectors are brought outside the convection shaft.

The boiler is equipped with 2 regenerative rotary air heaters RVP-54.

^ TECHNICAL TASK
"Device for sampling flue gases of NGRES boilers"

TABLE OF CONTENTS:

1 ITEM 3

^ 2 GENERAL DESCRIPTION OF THE FACILITY 3

3 SCOPE OF DELIVERY / PERFORMANCE OF WORK / PROVISION OF SERVICES 6

4 TECHNICAL DATA 11

5 EXCLUSIONS/LIMITATIONS/OBLIGATIONS TO PROVIDE THE WORKS/SUPPLY/SERVICES 12

6 Testing, acceptance, commissioning 13

^ 7 LIST OF APPS 14

8 SAFETY REQUIREMENTS FOR WORK 14

9 ENVIRONMENTAL PROTECTION REQUIREMENTS BY CONTRACTORS 17

^ 10 ALTERNATIVE OFFERS 18

1ITEM

In accordance with the Environmental Program of OJSC Enel OGK-5 for 2011-2015, the Nevinnomysskaya GRES branch of OJSC Enel OGK-5 requires the following:

1. 
   Determination of the actual value of the concentration of nitrogen oxides, carbon monoxide, methane at different loads and different operating modes of boilers TGM-96 (boiler No. 4) instrument park of the performer.
2. 
   Determination of the distribution density of nitrogen dioxide over the area of ​​the convective surface in the control section.

3. Evaluation of the reduction in the formation of nitrogen oxides due to the use of regime measures and changes in the technical and economic indicators of boiler operation ( determining the effectiveness of the application of regime measures).

4. Development of proposals for the use of low-cost reconstructive measures aimed at reducing emissions of nitrogen oxides.

^

2GENERAL DESCRIPTION OF THE OBJECT

1. 
   General information

The Nevinnomyssk State District Power Plant (NGRES) with a design capacity of 1340 MW is designed to cover the needs for electricity in the North Caucasus and supply thermal energy to enterprises and the population of the city of Nevinnomyssk. At present, the installed capacity of Nevinnomysskaya GRES is 1,700.2 MW.

The GRES is located on the northern outskirts of the city of Nevinnomyssk and consists of a combined heat and power plant (CHP), open-type condensing power units (block part) and a combined cycle plant (CCGT).

Full name of the facility: branch "Nevinnomysskaya GRES" of Open Joint Stock Company "Enel Fifth Generating Company of the Wholesale Electricity Market" in the city of Nevinnomyssk, Stavropol Territory.

Location and postal address: Russian Federation, 357107, Nevinnomyssk city, Stavropol Territory, Energetikov street, 2.

1. 
   ^ Climatic conditions

Climate: temperate continental

The climatic conditions and parameters of the ambient air in this area correspond to the location of the state district power station (Nevinnomyssk) and are characterized by the data in Table 2.1.

Table 2.1 Climatic data for the region (Nevinnomyssk from SNiP 23-01-99)

edge, point	Outside air temperature, deg. FROM
	Outside air temperature, monthly average, deg. FROM
	I	II	III	IV		V	VI		VII	VIII		IX	X	XI		XII
Stavropol	-3,2	-2,3	1,3	9,3		15,3	19,3		21,9	21,2		16,1	9,6	4,1		-0,5
					Less than 8℃						Less than 10℃
Average annual	The coldest five-day period with a security of 0.92				Duration, days			Average temperature, deg. FROM			Duration, days				Average temperature, deg. FROM
9,1	-19				168			0,9			187				1,7

The long-term average air temperature of the coldest winter month (January) is minus 4.5°С, the hottest (July) is +22.1°С.

The duration of the period with stable frosts is about 60 days,

The wind speed, the frequency of which does not exceed 5%, is equal to - 10-11 m/s.

The prevailing wind direction is east.

The annual relative humidity is 62.5%.

1. 
   ^ CHARACTERISTICS AND BRIEF DESCRIPTION OF THE BOILER UNIT TGM - 96.

Gas-oil boiler type TGM-96 of the Taganrog boiler plant is single-drum, with natural circulation, steam capacity 480 t/h with the following parameters:

Pressure in the drum - 155 ati

Pressure behind the main steam valve - 140 ati

Superheated steam temperature - 560С

Feed water temperature - 230С
^ The main design data of the boiler when burning gas:
Steam capacity t/h 480

Superheated steam pressure kg / cm 2 140

Superheated steam temperature С 560

Feed water temperature С 230

Cold air temperature before RVV С 30

Hot air temperature С 265
^ CHARACTERISTICS OF THE FURNACE

Volume of the combustion chamber m 3 1644 Heat stress of the furnace volume kcal/m 3 h 187.10 3

Hourly fuel consumption BP nm 3 /h t/h 37.2.10 3

^ STEAM TEMPERATURE

Behind wall superheater C 391 In front of end screens C 411

After end shields С 434 After middle shields С 529 After convective superheater inlet packages С 572

After the weekend packages of convective p / n. C 560

^ GAS TEMPERATURE

Behind the screens С 958

Behind the convective p/n С 738 Behind the water economizer С 314

Exhaust gases С 120
The layout of the boiler is U-shaped, with two convective shafts. The combustion chamber is shielded by evaporator pipes and panels of a radiant superheater.

The ceiling of the furnace of the horizontal flue of the rotary chamber is shielded by panels of the ceiling superheater. A screen superheater is located in the rotary chamber and the transition gas duct.

The side walls of the reversing chamber and the bevels of the convection shafts are shielded with wall-mounted water economizer panels. Convective superheater and water economizer are located in convective shafts.

The convective superheater packages are mounted on the suspended pipes of the water economizer.

The convective water economizer packages are supported on air-cooled beams.

The water entering the boiler passes successively overhead pipes, condensers, wall-mounted water economizer, convective water economizer and enters the drum.

Steam from the drum enters 6 panels of the wall-mounted radiant superheater, from the radiant to the ceiling, from the ceiling to the screen, from the screen to the ceiling-wall and then to the convective superheater. The steam temperature is controlled by two injections of its own condensate. The first injection is carried out on all boilers in front of the screen superheater, the second on K-4.5 and the third on 5A injections between the inlet and outlet packages of the convective p / n, the second injection on K-5A into the cut of the outer and middle screens.

Three regenerative air heaters are installed on the rear side of the boiler to preheat the air required for fuel combustion. The boiler is equipped with two VDN-26 blowers. II and two smoke exhausters type DN26x2A.

The combustion chamber of the boiler unit has a prismatic shape. Clear dimensions of the combustion chamber:

Width - 14860 mm

Depth - 6080 mm

The volume of the combustion chamber is 1644 m 3 .

Apparent thermal stress of the furnace volume at a load of 480 t/h: - on gas 187.10 3 kcal/m 3 hour;

On fuel oil - 190.10 3 kcal / m 3 hour.

The combustion chamber is completely shielded by evaporator tubes dia. 60x6 with 64mm pitch and superheater tubes. To reduce the sensitivity of circulation to various thermal and hydraulic distortions, all evaporation screens are sectioned, and each section (panel) is an independent circulation circuit.

Boiler burner.

Name of quantities meas. Gas oil

1. Rated productivity kg/h 9050 8400
2. Air speed m/s 46 46
3. Speed ​​of gas outflow m/s 160 -
4. Burner resistance kg/m2 150 150

by air.
5. Maximum production - nm 3 / hour 11000

gas performance
6. Maximum production - kg / hour - 10000

fuel oil performance.
7. Adjustable limit % 100-60% 100-60%

loading. from nominal from nominal
8. Gas pressure in front of the burner. kg/m2 3500 -
9. Fuel oil pressure in front of the burner - kgf / cm 2 - 20

coy.
10. Minimum pressure drop - - - 7

fuel oil removal at lowered.

load.

Brief description of the burner - GMG type.
Burners consist of the following units:

a) a volute designed to uniformly supply peripheral air to the guide vanes,

b) guide vanes with a register installed at the inlet to the peripheral air supply chamber. The guide vanes are designed to turbulize the flow of peripheral air and change its twist. Increasing its twist by covering the guide vanes increases the conicity of the torch and reduces its range and vice versa,

c) a chamber of the central air supply, formed on the inside by the surface of a pipe with a diameter of 219 mm, which simultaneously serves to install a working oil nozzle in it and from the outside with a pipe surface of dia. 478 mm, which is also the inner surface of the chamber at the outlet to the furnace, has 12 fixed guide vanes (socket), which are designed to turbulize the air flow directed to the center of the torch.

d) chambers of peripheral air supply, formed on the inner side by the surface of a pipe with a diameter of 529 mm, which is simultaneously the outer surface of the chamber of the central gas supply and, on the outer side, the surface of the pipe dia. 1180mm, which is also the inner surface of the peripheral gas supply chamber,

e) a chamber of the central gas supply, which has a row of nozzles with a diameter of 18 mm (8 pcs) and a row of holes dia. 17 mm (16 pcs). Nozzles and holes are arranged in two rows around the circumference of the outer surface of the chamber,

f) a chamber for peripheral gas supply, having two rows of nozzles with a diameter of 25 mm in the amount of 8 pcs and dia. 14 mm in the amount of 32 pcs. The nozzles are located around the circumference of the inner surface of the chamber.

For the possibility of regulating the air flow on the burners, the following are installed:

Common damper on the air supply to the burner,

Gate valve on the peripheral air supply,

Gate on the central air supply.

To prevent air infiltration into the furnace, a damper is installed on the guide pipe of the fuel oil nozzle.

MINISTRY OF ENERGY AND ELECTRIFICATION OF THE USSR

MAIN TECHNICAL DEPARTMENT FOR OPERATION
ENERGY SYSTEMS

TYPICAL ENERGY DATA
OF THE TGM-96B BOILER FOR FUEL FUEL COMBUSTION

Moscow 1981

This Typical Energy Characteristic was developed by Soyuztekhenergo (engineer G.I. GUTSALO)

The typical energy characteristic of the TGM-96B boiler was compiled on the basis of thermal tests conducted by Soyuztekhenergo at the Riga CHPP-2 and Sredaztekhenergo at the CHPP-GAZ, and reflects the technically achievable efficiency of the boiler.

A typical energy characteristic can serve as the basis for compiling the standard characteristics of TGM-96B boilers when burning fuel oil.

Appendix

. BRIEF DESCRIPTION OF THE BOILER INSTALLATION EQUIPMENT

1.1 . Boiler TGM-96B of the Taganrog Boiler Plant - gas-oil with natural circulation and U-shaped layout, designed to work with turbines T -100/120-130-3 and PT-60-130/13. The main design parameters of the boiler when operating on fuel oil are given in Table. .

According to the TKZ, the minimum allowable load of the boiler according to the circulation condition is 40% of the nominal one.

1.2 . The combustion chamber has a prismatic shape and in plan is a rectangle with dimensions of 6080 × 14700 mm. The volume of the combustion chamber is 1635 m 3 . The thermal stress of the furnace volume is 214 kW/m 3 , or 184 10 3 kcal/(m 3 h). Evaporative screens and a radiation wall superheater (RNS) are placed in the combustion chamber. In the upper part of the furnace in the rotary chamber there is a screen superheater (SHPP). In the lowering convective shaft, two packages of a convective superheater (CSH) and a water economizer (WE) are located in series along the gas flow.

1.3 . The steam path of the boiler consists of two independent flows with steam transfer between the sides of the boiler. The temperature of the superheated steam is controlled by injection of its own condensate.

1.4 . On the front wall of the combustion chamber there are four double-flow oil-gas burners HF TsKB-VTI. The burners are installed in two tiers at elevations of -7250 and 11300 mm with an elevation angle of 10° to the horizon.

For burning fuel oil, steam-mechanical nozzles "Titan" are provided with a nominal capacity of 8.4 t / h at a fuel oil pressure of 3.5 MPa (35 kgf / cm 2). The steam pressure for blowing off and spraying fuel oil is recommended by the plant to be 0.6 MPa (6 kgf/cm2). Steam consumption per nozzle is 240 kg/h.

1.5 . The boiler plant is equipped with:

Two draft fans VDN-16-P with a capacity of 259 10 3 m 3 / h with a margin of 10%, a pressure of 39.8 MPa (398.0 kgf / m 2) with a margin of 20%, a power of 500/250 kW and a rotation speed of 741 /594 rpm each machine;

Two smoke exhausters DN-24 × 2-0.62 GM with a capacity of 10% margin 415 10 3 m 3 / h, pressure with a margin of 20% 21.6 MPa (216.0 kgf / m 2), power 800/400 kW and a speed of 743/595 rpm of each machine.

1.6. To clean the convective heating surfaces from ash deposits, the project provides for a shot plant, for cleaning the RAH - water washing and blowing with steam from a drum with a decrease in pressure in the throttling plant. The duration of blowing one RAH 50 min.

. TYPICAL ENERGY CHARACTERISTICS OF THE TGM-96B BOILER

2.1 . Typical energy characteristic of the TGM-96B boiler ( rice. , , ) was compiled on the basis of the results of thermal tests of boilers at Riga CHPP-2 and CHPP GAZ in accordance with the instructive materials and methodological guidelines for standardizing the technical and economic indicators of boilers. The characteristic reflects the average efficiency of a new boiler operating with turbines T -100/120-130/3 and PT-60-130/13 under the following conditions taken as initial.

2.1.1 . The fuel balance of power plants burning liquid fuels is dominated by high-sulphur fuel oil M 100. Therefore, the characteristic is drawn up for fuel oil M 100 (GOST 10585-75 ) with characteristics: A P = 0.14%, W P = 1.5%, S P = 3.5%, (9500 kcal/kg). All necessary calculations are made for the working mass of fuel oil

2.1.2 . The temperature of the fuel oil in front of the nozzles is assumed to be 120 ° C( t t= 120 °С) based on fuel oil viscosity conditions M 100, equal to 2.5 ° VU, according to § 5.41 PTE.

2.1.3 . The average annual temperature of cold air (t x .c.) at the inlet to the blower fan is taken equal to 10 ° C , since TGM-96B boilers are mainly located in climatic regions (Moscow, Riga, Gorky, Chisinau) with an average annual air temperature close to this temperature.

2.1.4 . The air temperature at the inlet to the air heater (t vp) is taken equal to 70 ° C and constant when the boiler load changes, in accordance with § 17.25 PTE.

2.1.5 . For power plants with cross connections, the feed water temperature (t a.c.) in front of the boiler is taken as calculated (230 °C) and constant when the boiler load changes.

2.1.6 . The specific net heat consumption for the turbine plant is assumed to be 1750 kcal/(kWh), according to thermal tests.

2.1.7 . The heat flow coefficient is assumed to vary with the boiler load from 98.5% at rated load to 97.5% at a load of 0.6D number.

2.2 . The calculation of the standard characteristic was carried out in accordance with the instructions of the “Thermal calculation of boiler units (normative method)”, (M.: Energia, 1973).

2.2.1 . The gross efficiency of the boiler and the heat loss with flue gases were calculated in accordance with the methodology described in the book by Ya.L. Pekker "Heat engineering calculations based on the reduced characteristics of the fuel" (M.: Energia, 1977).

where

here

α uh = α "ve + Δ α tr

α uh- coefficient of excess air in the exhaust gases;

Δ α tr- suction cups in the gas path of the boiler;

T uh- flue gas temperature behind the smoke exhauster.

The calculation takes into account the flue gas temperatures measured in the boiler thermal tests and reduced to the conditions for constructing a standard characteristic (input parameterst x in, t "kf, t a.c.).

2.2.2 . Excess air coefficient at the mode point (behind the water economizer)α "ve taken equal to 1.04 at rated load and changing to 1.1 at 50% load according to thermal tests.

The reduction of the calculated (1.13) excess air coefficient downstream of the water economizer to the one adopted in the standard characteristic (1.04) is achieved by the correct maintenance of the combustion mode according to the boiler’s regime map, compliance with the PTE requirements regarding air suction into the furnace and into the gas path and selection of a set of nozzles .

2.2.3 . Air suction into the gas path of the boiler at rated load is taken equal to 25%. With a change in load, air suction is determined by the formula

2.2.4 . Heat losses from chemical incompleteness of fuel combustion (q 3 ) are taken equal to zero, since during the tests of the boiler with excess air, accepted in the Typical energy characteristic, they were absent.

2.2.5 . Heat loss from mechanical incompleteness of fuel combustion (q 4 ) are taken equal to zero according to the "Regulations on the harmonization of the regulatory characteristics of equipment and estimated specific fuel consumption" (M.: STsNTI ORGRES, 1975).

2.2.6 . Heat loss to the environment (q 5 ) were not determined during the tests. They are calculated in accordance with the "Method of testing boiler plants" (M.: Energia, 1970) according to the formula

2.2.7 . The specific power consumption for the feed electric pump PE-580-185-2 was calculated using the characteristics of the pump adopted from the specifications TU-26-06-899-74.

2.2.8 . The specific power consumption for draft and blast is calculated from the power consumption for the drive of draft fans and smoke exhausters, measured during thermal tests and reduced to the conditions (Δ α tr= 25%), adopted in the preparation of the regulatory characteristics.

It has been established that at a sufficient density of the gas path (Δ α ≤ 30%) smoke exhausters provide the rated load of the boiler at low speed, but without any reserve.

Blow fans at low speed ensure normal operation of the boiler up to loads of 450 t/h.

2.2.9 . The total electric power of the mechanisms of the boiler plant includes the power of electric drives: electric feed pump, smoke exhausters, fans, regenerative air heaters (Fig. ). The power of the electric motor of the regenerative air heater is taken according to the passport data. The power of the electric motors of smoke exhausters, fans and the electric feed pump was determined during the thermal tests of the boiler.

2.2.10 . The specific heat consumption for air heating in a calorific unit is calculated taking into account air heating in fans.

2.2.11 . The specific heat consumption for auxiliary needs of the boiler plant includes heat losses in heaters, the efficiency of which is assumed to be 98%; for steam blowing of RAH and heat loss with steam blowing of the boiler.

The heat consumption for steam blowing of RAH was calculated by the formula

Q obd = G obd · i obd · τ obd 10 -3 MW (Gcal/h)

where G obd= 75 kg/min in accordance with the "Standards for the consumption of steam and condensate for auxiliary needs of power units 300, 200, 150 MW" (M.: STSNTI ORGRES, 1974);

i obd = i us. pair= 2598 kJ/kg (kcal/kg)

τ obd= 200 min (4 devices with a blowing time of 50 min when switched on during the day).

The heat consumption with the boiler blowdown was calculated by the formula

Q prod = G prod · i k.v10 -3 MW (Gcal/h)

where G prod = PD nom 10 2 kg/h

P = 0.5%

i k.v- enthalpy of boiler water;

2.2.12 . The procedure for conducting tests and the choice of measuring instruments used in the tests were determined by the "Method of testing boiler plants" (M .: Energia, 1970).

. AMENDMENTS TO REGULATIONS

3.1 . In order to bring the main normative indicators of the boiler operation to the changed conditions of its operation within the permissible deviation limits of the parameter values, amendments are given in the form of graphs and numerical values. Amendments toq 2 in the form of graphs are shown in fig. , . Corrections to flue gas temperature are shown in fig. . In addition to the above, corrections are given for the change in the temperature of heating fuel oil supplied to the boiler, and for the change in the temperature of the feed water.

3.1.1 . The correction for the change in the temperature of the fuel oil supplied to the boiler is calculated from the effect of the change TO Q on the q 2 by formula