M. A. Taimarov, A. V. Simakov

RESULTS OF MODERNIZATION AND INCREASE TESTS

THERMAL POWER OF THE TGM-84B BOILER

Key words: steam boiler, testing, thermal power, nominal steam output, gas falling holes.

The work experimentally showed that the design of the TGM-84B boiler makes it possible to increase its steam production 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, compared to 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-performance boilers. In this regard, a significant reserve of area of heat-receiving screen heating surfaces was made, which, as all experience in operating TGM-84B boilers has shown, is not necessary. The performance of burners on TGM-84B boilers was also reduced due to the smaller diameter of the gas outlet holes. According to the first factory drawing of the Taganrog Boiler Plant, the second row of gas outlets in the burners are provided with a diameter of 25 mm, and later, based on operating experience to increase the thermal intensity of the furnaces, this diameter of the second row of gas outlets was increased to 27 mm. However, there is still room to increase the diameter of the gas outlet openings of the burners in order to increase the steam production of TGM-84B boilers.

Relevance and statement of the research problem

In the near future, the need for thermal and electrical energy. The growth in energy consumption is associated, on the one hand, with the use of foreign technologies for advanced processing of oil, gas, wood, and metallurgical products directly on the territory of Russia, and on the other, with the retirement and reduction of power due to the physical wear and tear 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 need for energy resources:

1. Introduction of new heat and electricity generating equipment.

2. Modernization and reconstruction of existing operational equipment.

The first direction requires large investments.

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

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

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

The double-light screen provides more intensive cooling of the flue gases than in the TGM-9bB gas-oil boiler of similar performance, which does not have a double-light screen. The dimensions of the furnaces of the TGM-9bB and TGM-84B boilers are almost the same. Design versions, with the exception of the presence of a two-light screen in the TGM-84B boiler, are also identical. The nominal steam output of the TGM-84B boiler is 420 t/hour, and for the TGM-9bB boiler the nominal steam output is 480 t/hour. 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 the TGM-9bB boiler.

Basic comparative specifications boilers TGM-84B and TGM-9bB are given in table 1.

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

Name of indicators TGM-84B TGM-96B

Steam capacity, t/h 420 480

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

Dual-light screen Yes No

Nominal thermal power 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/hour 33500 36800

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

4 °C), kg/cm2

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

Required air flow for blasting at nominal steam 3/ load, thousand m / hour 345.2 394.5

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

load, thousand m/hour

Certified nominal total capacity of 2 blower fans VDN-26-U, thousand m3/hour 506 506

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

From the 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 removing combustion products by two D-21.5x2U smoke exhausters with a margin of 29%.

Technical and Constructive decisions to increase the thermal power of the TGM-84B boiler

At the Department of Boiler Installations of Kazan State Power Engineering University, work was carried out to increase the thermal power of the TGM-84B boiler st. No. 10 NchCHPP. Thermal-hydraulic calculation was carried out

burners with 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 outlet holes were drilled out (evenly around the circumference through one hole) 2- 1st row from diameter 027 mm to diameter 029 mm. The incident flows, flame temperature and other operating parameters of boiler No. 10 were measured (Table 2). The unit thermal power of the burners increased by 6.09% and amounted to 332.28 MW instead of 301.2 MW before drilling. Steam output increased by 6.04% and amounted to 447 t/hour instead of 420 t/hour before drilling.

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

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

Thermal power of one burner, MW 50.2 55.58

Thermal power of the furnace, MW 301.2 332.28

Increase in thermal power of the furnace,% - 6.09

Boiler steam output, t/hour 420 441

Increase in steam output,% - 6.04

Calculations and tests of modernized boilers have shown that there is no separation of the gas jet from the gas supply openings 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 disruption of the gas flow at low loads.

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

holes from 0.205 m to 0.218 m made it possible to increase the nominal steam output from 420 t/h to 447 t/h when burning gas.

Literature

1. Taimarov, M.A. High power and supercritical thermal power plant boilers Part 1: textbook / M.A. Taimarov, V.M. Taimarov. Kazan: Kazan. state energy univ., 2009. - 152 p.

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

3. Taimarov, M.A. Laboratory workshop on the course “Boiler installations and steam generators” / M.A. Taimarov. - Kazan: Kazan. state energy univ., 2004. - 107 p.

INFLUENCE OF STEAM LOAD OF RADIATION PROPERTIES OF THE TORCH IN THE BOILER FIRE CHAMBER

Mikhail Taimarov

dr. sci. tech., professor of the Kazan state energetic university,

Rais Sungatullin

high teacher of the Kazan state energetic university,

Russia, Republic of Tatarstan, Kazan

ANNOTATION

This paper examines the heat flow from the torch during combustion natural gas in the TGM-84A boiler (station No. 4) of Nizhnekamsk CHPP-1 (NkCHP-1) for various operating conditions in order to determine the conditions under which the lining of the rear screen is least susceptible to thermal destruction.

ABSTRACT

In this operation the heat flux from a torch in case of combustion of natural gas in the boiler TGM-84A (station No. 4) of Nizhnekamsk TETc-1 (NkTETs-1) for different regime conditions for the purpose of determination of conditions under which the brickwork envelope of the back screen is least subject to thermal corrupting is considered.

Keywords: steam boilers, heat flows, air circulation parameters.

Keywords: boilers, heat fluxes, air twisting parameters.

Introduction.

Boiler TGM-84A, a widely used gas-oil boiler, has relatively small dimensions. Its combustion chamber is divided by a two-light screen. The lower part of each side screen passes into a slightly inclined bottom screen, the lower collectors of which are attached to the collectors of the two-light screen and move together with thermal deformations during firing and shutdown of the boiler. The inclined hearth tubes are protected from torch radiation by a layer of refractory brick and chromite mass. The presence of a two-light screen provides intensive cooling of flue gases.

In the upper part of the firebox, the rear screen pipes are bent into the combustion chamber, forming a threshold with an overhang of 1400 mm. This ensures that the screens are washed and protected from direct radiation from the torch. Ten pipes of each panel are straight, have no protrusion into the firebox and are load-bearing. Above the threshold there are screens, which are part of the superheater and are designed to cool the combustion products and superheat the steam. The presence of a two-light screen, as conceived by the designers, should provide more intensive cooling of the flue gases than in the TGM-96B gas-oil boiler, which is similar in performance. However, the area of the heating screen surface has a significant margin, which is practically higher than that required for the nominal operation of the boiler.

The basic model TGM-84 was repeatedly reconstructed, as a result of which, as indicated above, the TGM-84A model (with 4 burners) and then TGM-84B appeared. (6 burners). The boilers of the first modification TGM-84 were equipped with 18 oil-gas burners placed in three rows on the front wall of the combustion chamber. Currently, either four or six higher-capacity burners are installed.

The combustion chamber of the TGM-84A boiler is equipped with four gas-oil burners HF-TsKB-VTI-TKZ with a unit power of 79 MW, installed in two tiers in a row with their tops on the front wall. The burners of the lower tier (2 pcs.) are installed at 7200 mm, the upper tier (2 pcs.) - at 10200 mm. The burners are designed for separate combustion of gas and fuel oil. Gas burner productivity 5200 nm 3 /hour. Ignition of the boiler using steam-mechanical nozzles. To regulate the temperature of superheated steam, 3 stages of injection of own condensate are installed.

The HF-TsKB-VTI-TKZ vortex burner is a double-flow hot air burner and consists of a body, 2 sections of an axial (central) swirler and 1st section of a tangential (peripheral) air swirler, a central installation pipe for an oil nozzle and an igniter, gas distribution pipes . The main calculated (design) technical characteristics of the KhF-TsKB-VTI-TKZ burner are given in table. 1.

Table 1.

Main calculated (design) technical characteristicsburners HF-TsKB-VTI-TKZ:

Gas pressure, kPa
Gas consumption per burner, nm 3 / h
Burner thermal power, MW
Gas path resistance at rated load, mm water. Art.
Air path resistance at rated load, mm water. Art.
Overall dimensions, mm	3452x3770x3080
Total outlet cross-section of the hot air channel, m 2
Total outlet cross-section of gas pipes, m 2

Characteristics of the directions of air rotation in the KhF-TsKB-VTI-TKZ burners are shown in Fig. 1. The diagram of the twisting mechanism is shown in Fig. 2. The layout of gas exhaust pipes in the burners is shown in Fig. 3.

Figure 1. Scheme of burner numbering, air rotations in the burners and the location of the HF-TsKB-VTI-TKZ burners on the front wall of the furnace of TGM-84A boilers No. 4.5 NkTES-1

Figure 2. Diagram of the mechanism for air rotation in the burners HF-TsKB-VTI-TKZ boilers TGM-84A NkTES-1

The hot air box in the burner is divided into two streams. An axial swirling apparatus is installed in the internal channel, and an adjustable tangential swirler is installed in the peripheral tangential channel.

Figure 3. Layout of gas exhaust pipes in the burners HF-TSLB-VTI-TKZ of boilers TGM-84A NkTES-1

During the experiments, Urengoy gas with a calorific value of 8015 kcal/m 3 was burned. The experimental research technique is based on the use of a non-contact method for measuring the incident heat flows from the torch. In experiments, the magnitude of the heat flux falling from the torch onto the screens q the fall was measured with a radiometer calibrated in laboratory conditions.

Measurements of non-luminous combustion products in boiler furnaces were carried out in a non-contact manner using a radiation pyrometer of the RAPIR type, which showed the radiation temperature. The error in measuring the actual temperature of non-luminous products at their exit from the furnace at 1100°C using the radiation method for calibrating RK-15 with quartz lens material is estimated at ± 1.36%.

In general, the expression for the local value of the heat flux incident from the torch onto the screens is q the drop can be presented as a dependence on the actual temperature of the torch T f in the combustion chamber and the degree of emissivity of the torch α f, according to the Stefan-Boltzmann law:

q pad = 5.67 ´ 10 -8 α f T f 4, W/m 2,

Where: T f – temperature of combustion products in the torch, K. The brightness degree of emissivity of the torch α λf =0.8 was taken according to the recommendations.

Impact graph steam load The radiation properties of the torch are shown in Fig. 4. Measurements were taken at a height of 5.5 m through hatches No. 1 and No. 2 of the left side screen. The graph shows that with an increase in the steam load of the boiler, a very strong increase in the values of the falling heat fluxes from the torch in the area of the rear screen is observed. When measuring through a hatch located closer to the front wall, an increase in the values falling from the torch onto the heat flow screens with increasing load is also observed. However, in comparison with the heat flows at the rear screen, in absolute value the heat flows in the front screen area for heavy loads are on average 2 ... 2.5 times lower.

Figure 4. Distribution of incident heat flux q pad according to the depth of the furnace depending on the steam production D to according to measurements through hatches 1, 2 1st tier at 5.5 m along the left wall of the furnace for boiler TGM-84A No. 4 NkTES-1 with maximum air rotation in the position of the blades in burners 3 (the distance between hatches 1 and 2 is 6.0 m at the total depth of the furnace 7.4 m):

In Fig. Figure 5 shows graphs of the distribution of the incident heat flux q pad along the depth of the furnace depending on the steam production D k according to measurements through hatches No. 6 and No. 7 of the 2nd tier at an elevation of 9.9 m along the left wall of the furnace for the TGM-84A boiler No. 4 NKTETs at maximum air twist in the position of the blades in burners Z in comparison with the resulting heat flows as measured through hatches No. 1 and No. 2 of the first tier.

Figure 5. Distribution of incident heat flux q pad according to the depth of the furnace depending on the steam production D k according to measurements through hatches No. 6 and No. 7 of the 2nd tier at elevation. 9.9 m along the left wall of the furnace for the TGM-84A boiler No. 4 NKTETs with maximum air twist in the position of the blades in burners 3 in comparison with the resulting heat flows as measured through hatches No. 1 and No. 2 of the first tier (distance between hatches 6 and 7 equals 5.5 m with a total firebox depth of 7.4 m):

Designations for the position of air swirlers in burners adopted in this work:

Z – maximum twist, O – no twist, air flows without twist.

Index c – central twist, index p – peripheral main twist.

The absence of an index means the same position of the blades for the central and peripheral twists (or both twists in position O or both twists in position Z).

From Fig. Figure 5 shows that the highest values of heat flows from the torch to the heating screen surfaces occur according to measurements through hatch No. 6 of the second tier closest to the rear wall of the furnace at around 9.9 m. At around 9.9 m, according to measurements through hatch No. 6, the growth heat flows from the torch occur at a rate of 2 kW/m2 for every 10 t/h increase in steam load, while for burner No. 1 of the first tier at around 5.5 m, the increase in heat flows from the torch to the rear screen occurs at a rate of 8 kW/m2 for every 10 t/hour increase in steam load.

The growth of heat flows falling from the torch to the rear screen, as measured through hatch No. 1 at the 5.5 m mark of the first tier, with an increase in the load of the TGM-84A boiler No. 4 NKTETs for conditions of maximum air rotation in the burners occurs 4 times faster compared to growth of heat flows near the rear screen at around 9.9 m.

Maximum density thermal radiation from the torch to the rear screen, as measured through hatch No. 6 at around 9.9 m, even with the maximum steam output of the TGM-84A boiler No. 4 NKTETs-1 420 t/hour for conditions of maximum air rotation in the burners (twist blade position 3) on average by 23% higher compared to the value of radiation density from the torch at the rear screen at the level of 5.5 m as measured through hatch No. 1.

The resulting heat flows, obtained from measurements at an elevation of 9.9 m through hatch No. 7 of the second tier (closest to the front screen), with an increase in the steam load of the TGM-84A boiler No. 4 NKHPP from 230 t/h to 420 t/h for maximum conditions The air twist in the burners (position of the twist blades 3) for every 10 t/hour increases by 2 kW/m2, i.e., as in the above-mentioned case, as measured through hatch No. 6 closest to the rear screen at around 9.9 m.

An increase in the values of the falling heat flows, as measured through hatch No. 7 of the second tier at the level of 9.9 m, occurs with an increase in the steam load of the TGM-84A boiler No. 4 NKTETs from 230 t/h to 420 t/h for every 10 t/h at a rate of 4 .7 kW/m2, i.e. 2.35 times slower in comparison with the growth of heat fluxes falling from the torch as measured through hatch No. 2 at around 5.5 m.

Measurements of heat flows falling from the torch through hatch No. 7 at 9.9 m at a boiler steam load of 420 t/h practically coincide with the values obtained from measurements through hatch No. 2 at 5.5 m for conditions of maximum air rotation in the burners (position of the twist blades Z) of the TGM-84A boiler No. 4 NKTETs.

Conclusions.

1. The effect on the magnitude of heat flows from the torch of changes in the axial (central) air twist in the burners, compared to the change in the tangential air twist in the burners, is small and is more noticeable at around 5.5 m along section 2.

2. The highest measured flows occurred in the absence of tangential (peripheral) air rotation in the burners and amounted to 362.7 kW/m2 as measured through hatch No. 6 at 9.9 m at a load of 400 t/hour. Values of heat flows from the torch in the range of 360 ... 400 kW/m 2 are dangerous when the furnace operates in the mode of direct throwing of the torch onto the furnace wall from the fire side due to the gradual destruction of the internal lining.

Bibliography:

Harrison T.R. Radiation pyrometry. – M.: Mir, 1964, 248 p.
Gordov A.N. Fundamentals of pyrometry - M.: Metallurgy, 1964, 471 p.
Taimarov M.A. Laboratory workshop on the course “Boiler installations and steam generators”. Textbook Kazan, KSPEU 2002, 144 p.
Taimarov M.A. Study of the efficiency of energy facilities. – Kazan: Kazan. state energy univ., 2011. 110 p.
Taimarov M.A. Practical exercises at the thermal power plant. – Kazan: Kazan. state energy univ., 2003., 90 p.
Thermal radiation detectors. Proceedings of the 1st All-Union Symposium. Kyiv, Naukova Dumka, 1967. 310 p.
Shubin E.P., Livin B.I. Design of heat treatment plants for thermal power plants and boiler houses - M.: Energia, 1980, 494 p.
Trasition Metal Pyrite Dichaicogenides: High-Pressure Synthesis and Correlation of Properties / T.A. Bither, R.I. Bouchard, W.H. Cloud et al. // Inorg. Chem. – 1968. – V. 7. – P. 2208–2220.

MINISTRY OF ENERGY AND ELECTRIFICATION OF THE USSR

MAIN TECHNICAL DEPARTMENT FOR OPERATION
ENERGY SYSTEMS

TYPICAL ENERGY CHARACTERISTICS
BOILER TGM-96B FOR FUEL OIL COMBUSTION

Moscow 1981

This Standard Energy Characteristic was developed by Soyuztekhenergo (eng. G.I. GUTSALO)

The typical energy characteristics of the TGM-96B boiler are compiled on the basis of thermal tests carried out by Soyuztekhenergo at Riga CHPP-2 and Sredaztekhenergo at CHPP-GAZ, and reflect the technically achievable efficiency of the boiler.

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

Application

. BRIEF CHARACTERISTICS OF BOILER EQUIPMENT

1.1 . TGM-96B boiler of the Taganrog Boiler Plant - gas-oil boiler 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 TKZ, the minimum permissible boiler load according to circulation conditions is 40% of the nominal one.

1.2 . The combustion chamber has a prismatic shape and in plan is a rectangle with dimensions 6080x14700 mm. The volume of the combustion chamber is 1635 m3. The thermal voltage of the combustion volume is 214 kW/m 3, or 184 · 10 3 kcal/(m 3 · h). The combustion chamber contains evaporation screens and a radiation wall-mounted steam superheater (WSR) on the front wall. In the upper part of the furnace, a screen steam superheater (SSH) is located in the rotating chamber. In the lower convective shaft, two packages of a convective steam superheater (CS) and a water economizer (WES) are located sequentially along the flow of gases.

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 regulated by the injection of its own condensate.

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

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

1.5 . The boiler installation is equipped with:

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

Two smoke exhausters DN-24×2-0.62 GM with a capacity of 415 10 3 m 3 /h with a margin of 10%, a pressure with a margin of 20% of 21.6 MPa (216.0 kgf/m2), power of 800/400 kW and a rotation speed of 743/595 rpm for each machine.

1.6. To clean convective heating surfaces from ash deposits, the project provides for a shot installation; for cleaning the RVP, water washing and blowing with steam from a drum with a decrease in pressure in the throttling installation. The duration of blowing one RVP is 50 minutes.

. TYPICAL ENERGY CHARACTERISTICS OF THE TGM-96B BOILER

2.1 . Typical energy characteristics of the TGM-96B boiler ( rice. , , ) was compiled on the basis of the results of thermal tests of boilers at Riga CHPP-2 and GAZ CHPP in accordance with instructional materials and 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 conditions below, taken as initial ones.

2.1.1 . In the fuel balance of power plants burning liquid fuels, the majority is high-sulfur fuel oil M 100. Therefore, the characteristics are 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 were performed for the working mass of fuel oil

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

2.1.3 . Average annual cold air temperature (t x .v.) at the entrance to the blower fan is taken to be 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 . Air temperature at the inlet to the air heater (t ch) is taken to be 70° C and constant when the boiler load changes, according to § 17.25 of the PTE.

2.1.5 . For cross-coupled power plants, the feedwater temperature (t p.v.) in front of the boiler is assumed to be calculated (230 °C) and constant when the boiler load changes.

2.1.6 . The specific net heat consumption for the turbine unit 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 0.6 loadD nom.

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

2.2.1 . The gross efficiency of the boiler and heat loss with flue gases were calculated in accordance with the methodology outlined in the book by Ya.L. Pekker “Thermal engineering calculations based on the given fuel characteristics” (Moscow: Energia, 1977).

Where

Here

α х = α "ve + Δ α tr

α х- coefficient of excess air in exhaust gases;

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

Ugh- temperature of the flue gases behind the smoke exhauster.

The calculation includes the flue gas temperature values measured in boiler thermal tests and reduced to the conditions for constructing the standard characteristics (input parameterst x in, t "kf, t p.v.).

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

Reducing the calculated (1.13) coefficient of excess air behind the water economizer to that accepted in the standard specification (1.04) is achieved by correctly maintaining the combustion mode in accordance with the boiler regime map, complying with the requirements of the PTE in relation to air intake into the furnace and into the gas path and selecting a set of nozzles .

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

2.2.4 . Heat loss from chemical incomplete combustion of fuel (q 3 ) are taken equal to zero, since during tests of the boiler with excess air, accepted in the Standard Energy Characteristics, they were absent.

2.2.5 . Heat loss from mechanical incomplete combustion of fuel (q 4 ) are taken equal to zero according to the “Regulations on the coordination of standard characteristics of equipment and calculated specific fuel consumption” (Moscow: STSNTI ORGRES, 1975).

2.2.6 . Heat loss in environment (q 5 ) were not determined during testing. They are calculated in accordance with the “Methods for testing boiler installations” (M.: Energia, 1970) according to the formula

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

2.2.8 . The specific energy consumption for draft and blast is calculated based on the energy consumption for driving blower fans and smoke exhausters, measured during thermal tests and reduced to conditions (Δ α tr= 25%) adopted when drawing up the normative characteristics.

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

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

2.2.9 . The total electrical power of the boiler installation mechanisms 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 the smoke exhausters, fans and electric feed pump was determined during thermal tests of the boiler.

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

2.2.11 . The specific heat consumption for the boiler plant’s own needs includes heat losses in air heaters, the efficiency of which is assumed to be 98%; for steam blowing of the RVP and heat losses due to steam blowing of the boiler.

The heat consumption for steam blowing of the RVP was calculated using 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 the auxiliary needs of power units of 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 duration of 50 min when turned on during the day).

Heat consumption with boiler blowing was calculated using the formula

Q cont = G prod · i k.v· 10 -3 MW (Gcal/h)

Where G prod = PD no. 10 2 kg/h

P = 0.5%

i k.v- enthalpy of boiler water;

2.2.12 . The procedure for testing and the choice of measuring instruments used during testing were determined by the “Methodology for testing boiler installations” (M.: Energia, 1970).

. AMENDMENTS TO REGULATORY INDICATORS

3.1 . To bring the main standard indicators operation of the boiler to the changed conditions of its operation within the permissible limits of deviation of parameter values, amendments are given in the form of graphs and digital values. Amendments toq 2 in the form of graphs are shown in Fig. , . Corrections to the flue gas temperature are shown in Fig. . In addition to those listed, corrections are given for changes in the heating temperature of the fuel oil supplied to the boiler and for changes in the temperature of the feed water.

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

Compiled by: M.V. KALMYKOV UDC 621.1 Design and operation of the TGM-84 boiler: Method. decree/ Samar. state tech. University; Comp. M.V. Kalmykov. Samara, 2006. 12 p. The main technical characteristics, layout and description of the design of the TGM-84 boiler and the principle of its operation are considered. The drawings of the boiler unit layout with auxiliary equipment, general view boiler and its components. A diagram of the boiler's steam-water path and a description of its operation are presented. The guidelines are intended for students of specialty 140101 “Thermal power plants”. Il. 4. Bibliography: 3 titles. Published by decision of the editorial and publishing council of SamSTU 0 MAIN CHARACTERISTICS OF THE BOILER UNIT TGM-84 boiler units are designed to produce steam high pressure when burning gaseous fuel or fuel oil and are designed for the following parameters: Nominal steam output …………………………….. Operating pressure in the drum ……………………………………………………… Operating steam pressure behind the main steam valve……………. Temperature of superheated steam………………………………………. Feed water temperature …………………………………… Hot air temperature a) when burning fuel oil ………………………………………………………. b) when burning gas……………………………………………. 420 t/h 155 ata 140 ata 550 °C 230 °C 268 °C 238 °C Boiler unit TGM-84 vertical water tube, single drum, shaped layout, with natural circulation. It consists of a combustion chamber, which is an ascending flue duct and a descending convective shaft (Fig. 1). The combustion chamber is divided by a two-light screen. The lower part of each side screen passes into a slightly inclined bottom screen, the lower collectors of which are attached to the collectors of the two-light screen and move together with thermal deformations during the firing and shutdown of the boiler. The presence of a two-light screen provides more intensive cooling of flue gases. Accordingly, the thermal stress of the combustion volume of this boiler was chosen to be significantly higher than in pulverized coal units, but lower than in other standard sizes of gas-oil boilers. This simplified the operating conditions of the two-light screen pipes that receive greatest number heat. A semi-radiation screen superheater is located in the upper part of the furnace and in the rotating chamber. A horizontal convective steam superheater and a water economizer are located in the convective shaft. Behind the water economizer there is a chamber with receiving hoppers for shot cleaning. Two parallel-connected regenerative air heaters of the rotating type RVP-54 are installed after the convective shaft. The boiler is equipped with two VDN-26-11 type blower fans and two D-21 type smoke exhausters. The boiler was repeatedly reconstructed, as a result of which the TGM-84A model appeared, and then the TGM-84B. In particular, unified screens were introduced and a more uniform distribution of steam between the pipes was achieved. The transverse pitch of the pipes in the horizontal packages of the convective part of the steam superheater was increased, thereby reducing the likelihood of its contamination with fuel oil soot. 2 0 R and s. 1. Longitudinal and cross sections of the gas-oil boiler TGM-84: 1 – combustion chamber; 2 – burners; 3 – drum; 4 – screens; 5 – convective superheater; 6 – condensation unit; 7 – economizer; 11 – shot catcher; 12 – remote separation cyclone The boilers of the first modification TGM-84 were equipped with 18 gas-oil burners placed in three rows on the front wall of the combustion chamber. Currently, either four or six burners of higher productivity are installed, which simplifies the maintenance and repair of boilers. BURNER DEVICES The combustion chamber is equipped with 6 gas-oil burners installed in two tiers (in the form of 2 triangles in a row, with their vertices up, on the front wall). The burners of the lower tier are installed at 7200 mm, the upper tier at 10200 mm. The burners are designed for separate combustion of gas and fuel oil, vortex, single-flow with central gas distribution. The outermost burners of the lower tier are turned towards the axis of the half-firebox by 12 degrees. To improve the mixing of fuel with air, the burners have guide vanes, through which the air swirls. Along the axis of the burners, the boilers are equipped with fuel oil nozzles with mechanical spray; the barrel length of the fuel oil nozzle is 2700 mm. The design of the firebox and the layout of the burners must ensure a stable combustion process, its control, and also eliminate the possibility of the formation of poorly ventilated zones. Gas burners must operate stably, without separation or slippage of the torch, within the range of regulation of the boiler’s thermal load. Gas burners used on boilers must be certified and have manufacturer's passports. COMBUSTION CHAMBER The prismatic chamber is divided by a two-light screen into two half-combustion chambers. The volume of the combustion chamber is 1557 m3, the thermal voltage of the combustion volume is 177,000 kcal/m3ּhour. The side and rear walls of the chamber are shielded by evaporation pipes with a diameter of 60x6 mm with a pitch of 64 mm. The side screens in the lower part have slopes to the middle of the firebox with a slope of 15 degrees to the horizontal and form a floor. To avoid stratification of the steam-water mixture in pipes slightly inclined to the horizontal, sections of the side screens forming the underside are covered with fireclay bricks and chromite mass. The screen system is suspended from metal structures using rods ceiling and has the ability to freely fall down during thermal expansion. The pipes of the evaporation screens are welded together with a D-10 mm rod with a height interval of 4-5 mm. To improve the aerodynamics of the upper part of the combustion chamber and protect the rear screen chambers from radiation, the rear screen pipes in the upper part form a protrusion into the firebox with an overhang of 1.4 m. The protrusion is formed by 70% of the rear screen pipes. 3 In order to reduce the effect of uneven heating on circulation, all screens are sectioned. The two-light and two side screens each have three circulation circuits, the rear screen has six. TGM-84 boilers operate according to a two-stage evaporation scheme. The first stage of evaporation (clean compartment) includes a drum, rear and two-light screen panels, and 1st and 2nd side screen panels from the front. The second stage of evaporation (salt compartment) includes 4 remote cyclones (two on each side) and a third panel of side screens from the front. Water from the drum is supplied to the six lower chambers of the rear screen through 18 drainage pipes, three to each collector. Each of the 6 panels includes 35 screen pipes. The upper ends of the pipes are connected to chambers, from which the steam-water mixture flows through 18 pipes into the drum. The two-light screen has windows formed by pipe routing to equalize pressure in the half-furnaces. Water from the drum flows to the three lower chambers of the two-light screen through 12 drainage pipes (4 pipes for each collector). The outer panels have 32 screen pipes, the middle one - 29 pipes. The upper ends of the pipes are connected to three upper chambers, from which the steam-water mixture is directed through 18 pipes into the drum. Water flows to the four front lower side screen collectors from the drum through 8 drainage pipes. Each of these panels contains 31 screen pipes. The upper ends of the screen pipes are connected to 4 chambers, from which the steam-water mixture enters the drum through 12 pipes. The lower chambers of the salt compartments are fed from 4 remote cyclones through 4 drainage pipes (one pipe from each cyclone). The salt compartment panels each contain 31 screen pipes. The upper ends of the screen pipes are connected to chambers, from which the steam-water mixture flows through 8 pipes into 4 remote cyclones. DRUM AND SEPARATION DEVICE The drum has an internal diameter of 1.8 m, a length of 18 m. All drums are made of sheet steel 16 GNM (manganese-nickel-molybdenum steel), wall thickness 115 mm. The drum weight is about 96600 kg. The boiler drum is designed to be able to create natural circulation water in the boiler, cleaning and separation of steam produced in screen pipes. The separation of the steam-water mixture of the 1st stage of evaporation is organized in the drum (separation of the 2nd stage of evaporation is carried out on boilers in 4 remote cyclones), washing of all the steam is carried out with feed water, followed by the capture of moisture from the steam. The entire drum is a clean compartment. The steam-water mixture from the upper collectors (except for the salt compartment collectors) enters the drum from both sides and enters a special distribution box, from which it is sent to the cyclones, where the initial separation of steam from water occurs. There are 92 cyclones installed in the boiler drums - 46 left and 46 right. 4 At the steam outlet from the cyclones, horizontal plate separators are installed. The steam, having passed through them, enters the bubble-washing device. Here, under the washing device of the clean compartment, steam is supplied from external cyclones, inside of which the separation of the steam-water mixture is also organized. The steam, having passed through the bubble-washing device, enters the perforated sheet, where steam separation and flow equalization occur simultaneously. Having passed the perforated sheet, the steam is carried through 32 steam removal pipes to the inlet chambers of the wall-mounted superheater and through 8 pipes to the condensate unit. Rice. 2. Two-stage evaporation scheme with remote cyclones: 1 – drum; 2 – remote cyclone; 3 – lower collector circulation circuit ; 4 – steam generating pipes; 5 – lowering pipes; 6 – feed water supply; 7 – removal of purge water; 8 – water transfer pipe from the drum to the cyclone; 9 – steam transfer pipe from the cyclone to the drum; 10 – steam removal pipe from the unit About 50% of the feed water is supplied to the bubble-washing device, and the rest of it is drained through the distribution manifold into the drum below the water level. The average water level in the drum is 200 mm below its geometric axis. Permissible level fluctuations in the drum are 75 mm. To equalize the salt content in the salt compartments of the boilers, two drainage pipes were transferred, so the right cyclone feeds the lower left collector of the salt compartment, and the left one feeds the right one. 5 STEAM SUPERHEATER DESIGN The heating surfaces of the superheater are located in the combustion chamber, horizontal gas duct and drop shaft. The superheater circuit is made of a double-flow design with multiple mixing and transfer of steam across the width of the boiler, which allows the thermal distribution to be equalized across individual coils. Based on the nature of heat perception, the superheater can be divided into two parts: radiation and convection. The radiation part includes a wall-mounted superheater (NSP), the first row of screens (SHPS) and part of the ceiling superheater (CSP), shielding the ceiling of the combustion chamber. To the convective one - the second row of screens, part of the ceiling superheater and the convective superheater (CSC). Radiation wall-mounted superheater NPP pipes shield the front wall of the combustion chamber. The NPP consists of six panels, two of them have 48 and the rest have 49 pipes, the pitch between the pipes is 46 mm. Each panel has 22 down pipes, the rest are up pipes. Input and output collectors are located in an unheated area above the combustion chamber, intermediate collectors are located in an unheated area below the combustion chamber. The upper chambers are suspended from the metal structures of the ceiling using rods. The pipes are fastened in 4 tiers in height and allow vertical movement of the panels. Ceiling superheater The ceiling superheater is located above the firebox and horizontal flue, consists of 394 pipes placed at 35 mm intervals and connected by inlet and outlet manifolds. Sheet steam superheater The screen steam superheater consists of two rows of vertical screens (30 screens in each row) located in the upper part of the combustion chamber and the rotary flue. The pitch between the screens is 455 mm. The screen consists of 23 coils of equal length and two collectors (input and output), installed horizontally in an unheated area. Convective superheater A horizontal type convective superheater consists of left and right parts located in the gas duct of the lower shaft above the water economizer. Each side in turn is divided into two direct-flow stages. 6 STEAM PATH OF THE BOILER Saturated steam from the boiler drum through 12 steam transfer pipes enters the upper collectors of the NPP, from which it moves down through the middle pipes of 6 panels and enters the 6 lower collectors, after which it rises up through the outer pipes of 6 panels to the upper ones collectors, from which it is sent through 12 unheated pipes to the input collectors of the ceiling superheater. Next, the steam moves across the entire width of the boiler through the ceiling pipes and enters the superheater outlet manifolds located at back wall convective flue. From these collectors, the steam is divided into two streams and sent to the chambers of stage I desuperheaters, and then to the chambers of the outer screens (7 left and 7 right), after passing which both steam streams enter the intermediate stage II desuperheaters, left and right. In stage I and II desuperheaters, steam is transferred from the left side to the right side and vice versa, in order to reduce the thermal spread caused by gas misalignment. Having left the intermediate desuperheaters of the second injection, the steam enters the middle screen manifolds (8 left and 8 right), after passing through which it is directed to the input chambers of the gearbox. Between the top and lower parts The gearbox is equipped with stage III desuperheaters. Next, the superheated steam is sent through a steam pipeline to the turbines. Rice. 3. Boiler superheater diagram: 1 – boiler drum; 2 – radiation two-way radiation pipe panel (the upper collectors are conventionally shown on the left, and the lower ones on the right); 3 – ceiling panel; 4 – injection desuperheater; 5 – place of injection of water into steam; 6 – extreme screens; 7 – medium screens; 8 – convective packages; 9 – steam exit from the boiler 7 CONDENSATE UNIT AND INJECTION STEAM COOLERS To obtain its own condensate, the boiler is equipped with 2 condensate units (one on each side) located on the ceiling of the boiler above the convective part. They consist of 2 distribution collectors, 4 capacitors and a condensate collector. Each capacitor consists of a chamber D426×36 mm. The cooling surfaces of the condensers are formed by pipes welded to a tube sheet, which is divided into two parts and forms a water drainage and water supply chambers. Saturated steam from the boiler drum is directed through 8 pipes to four distribution manifolds. From each collector, steam is discharged to two condensers by pipes, 6 pipes to each condenser. Condensation of saturated steam coming from the boiler drum is carried out by cooling it with feed water. Feedwater after the suspension system is supplied to the water supply chamber, passes through the condenser tubes and exits into the drainage chamber and then to the water economizer. The saturated steam coming from the drum fills the steam space between the pipes, comes into contact with them and condenses. The resulting condensate through 3 pipes from each condenser enters two collectors, from there through regulators it is supplied to desuperheaters I, II, III of the left and right injections. Injection of condensate occurs due to the pressure made up of the difference in the Venturi pipe and the pressure drop in the steam path of the superheater from the drum to the injection point. Condensate is injected into the cavity of the Venturi pipe through 24 holes with a diameter of 6 mm, located around the circumference at the narrow point of the pipe. The Venturi pipe, at full load on the boiler, reduces the steam pressure by increasing its speed at the injection site by 4 kgf/cm2. The maximum performance of one condenser at 100% load and design parameters of steam and feedwater is 17.1 t/h. WATER ECONOMIZER The steel coil water economizer consists of 2 parts, located respectively in the left and right parts of the lower shaft. Each part of the economizer consists of 4 blocks: lower, 2 middle and upper. Openings were made along the height between the blocks. The water economizer consists of 110 coil packs located parallel to the front of the boiler. The coils in the blocks are located in checkerboard pattern in increments of 30 mm and 80 mm. The middle and upper blocks are installed on beams located in the flue. To protect against gas environment these beams are covered with insulation protected metal sheets 3 mm thick from the impact of a shot blasting machine. The lower blocks are suspended from the beams using racks. The racks allow for the possibility of removing the coil package during repairs. 8 The inlet and outlet chambers of the water economizer are located outside the flue ducts and are attached to the boiler frame with brackets. Cooling of the water economizer beams (the temperature of the beams during lighting and during operation should not exceed 250 °C) is carried out by supplying them with cold air from the pressure of the blower fans, with the air being discharged into the suction boxes of the blower fans. AIR HEATER Two RVP-54 regenerative air heaters are installed in the boiler room. The regenerative air heater RVP-54 is a counterflow heat exchanger consisting of a rotating rotor enclosed inside a stationary housing (Fig. 4). The rotor consists of a shell with a diameter of 5590 mm and a height of 2250 mm, made of sheet steel 10 mm thick and a hub with a diameter of 600 mm, as well as radial ribs connecting the hub to the shell, dividing the rotor into 24 sectors. Each sector is divided by vertical sheets into P and S. 4. Structural diagram of a regenerative air heater: 1 – box; 2 – drum; 3 – body; 4 – packing; 5 – shaft; 6 – bearing; 7 – seal; 8 – electric motor three parts. Sections of heating sheets are placed in them. The height of the sections is installed in two rows. The top row is the hot part of the rotor, made of spacer and corrugated sheets, 0.7 mm thick. The bottom row of sections is the cold part of the rotor and is made of spacer straight sheets, 1.2 mm thick. The cold end packing is more susceptible to corrosion and can be easily replaced. Inside the rotor hub there is a hollow shaft, which has a flange at the bottom on which the rotor rests; the hub is attached to the flange with studs. The RVP has two covers - upper and lower, with sealing plates installed on them. 9 The heat exchange process is carried out by heating the rotor packing in the gas flow and cooling it in the air flow. The sequential movement of the heated packing from the gas flow to the air flow is carried out by rotating the rotor at a frequency of 2 revolutions per minute. At each moment of time, out of 24 sectors of the rotor, 13 sectors are included in the gas path, 9 sectors are included in the air path, two sectors are turned off and are blocked by sealing plates. The air heater uses the counterflow principle: air is introduced from the outlet side and removed from the gas inlet side. The air heater is designed to heat air from 30 to 280 °C while cooling gases from 331 °C to 151 °C when operating on fuel oil. The advantage of regenerative air heaters is their compactness and low weight; the main disadvantage is a significant flow of air from the air side to the gas side (normative air suction is 0.2–0.25). BOILER FRAMEWORK The boiler frame consists of steel columns, connected by horizontal beams, trusses and braces, and serves to bear the loads from the weight of the drum, all heating surfaces, condensate installation, lining, insulation and service areas. The boiler frame is made of welded profiles and sheet steel. The frame columns are attached to the underground reinforced concrete foundation of the boiler, and the base (shoe) of the columns is poured with concrete. LINING The lining of the combustion chamber consists of refractory concrete, sovelite slabs and sealing magnesium coating. The thickness of the lining is 260 mm. It is installed in the form of panels that are attached to the boiler frame. The ceiling lining consists of panels 280 mm thick, freely lying on the superheater pipes. Panel structure: a layer of refractory concrete 50 mm thick, a layer of thermal insulating concrete 85 mm thick, three layers of sovelite slabs with a total thickness of 125 mm and a layer of sealing magnesium coating 20 mm thick applied to metal mesh. The lining of the turning chamber and the convective shaft are attached to panels, which in turn are attached to the boiler frame. The total thickness of the turning chamber lining is 380 mm: refractory concrete - 80 mm, thermal insulating concrete - 135 mm and four layers of 40 mm sovelite slabs. The lining of the convective steam superheater consists of one layer of thermal insulating concrete 155 mm thick, a layer of refractory concrete - 80 mm and four layers of sovelite slabs - 165 mm. Between the plates there is a layer of sovelite mastic 2÷2.5 mm thick. The lining of the water economizer is 260 mm thick and consists of fire-resistant and thermally insulating concrete and three layers of sovelite slabs. SAFETY MEASURES Operation of boiler units must be carried out in accordance with the current “Rules for the design and safe operation of steam and hot water boilers” approved by Rostechnadzor and “ Technical requirements on explosion safety of boiler installations operating on fuel oil and natural gas,” as well as the current “Safety Rules for servicing thermal power equipment of power plants.” Bibliography 1. Operating instructions for the TGM-84 energy boiler at the VAZ CHPP. 2. Meiklyar M.V. Modern boiler units TKZ. M.: Energy, 1978. 3. Kovalev A.P., Leleev N.S., Vilensky T.V. Steam generators: Textbook for universities. M.: Energoatomizdat, 1985. 11 Design and operation of the TGM-84 boiler Compiled by KALMYKOV Maxim Vitalievich Editor N.V. Vershina Technical editor G.N. Shankova Signed for publication on June 20, 2006. Format 60x84 1/12. Offset paper. Offset printing. Conditional p.l. 1.39. Conditional cr.-ott. 1.39. Academic ed. l. 1.25 Circulation 100. pp. – 171. _________________________________________________________________________________________________________ State educational institution higher professional education "Samara State Technical University" 432100. Samara, st. Molodogvardeyskaya, 244. Main building 12