The influence of steam load on the heat flow of the torch in the boiler furnace. Boiler auxiliary equipment Thermal calculation of the TGM 96 boiler

Full name:“Automated training course “Operation of the TGM-96B boiler unit when burning fuel oil and natural gas.”

Symbol:

Year of issue: 2007.

The automated training course on the operation of the TGM-96B boiler unit was developed for the training of operational personnel servicing boiler installations of this type and is a means of training, pre-exam preparation and examination testing for CHP personnel.

The AUK was compiled on the basis of regulatory and technical documentation used in the operation of TGM-96B boilers. It contains text and graphic material for interactive learning and testing of students.

This AUK describes the design and technological characteristics of the main and auxiliary equipment of TGM-96B boilers, namely: combustion chamber, drum, superheater, convective shaft, power unit, draft devices, regulation of steam and water temperatures, etc.

Start-up, normal, emergency and shutdown operating modes of a boiler installation are considered, as well as the main reliability criteria for heating and cooling steam lines, screens and other elements of the boiler.

The automatic control system of the boiler, the system of protection, interlocks and alarms are considered.

The procedure for admission to inspection, testing, and repair of equipment, safety rules and fire and explosion safety have been determined.

AUC composition:

Automated training course (ATC) is a software tool designed for initial training and subsequent testing of knowledge of personnel of power plants and electrical networks. First of all, for training operational and maintenance personnel.

The basis of AUC consists of existing production and job descriptions, regulatory materials, data from equipment manufacturers.

AUC includes:

• general theoretical information section;
• a section that discusses the design and operating rules of a specific type of equipment;
• student self-test section;
• examiner's block.

In addition to texts, the AUK contains the necessary graphic material (diagrams, drawings, photographs).

Information content of the AUC.

The text material is compiled on the basis of operating instructions for the TGM-96 boiler unit, factory instructions, other regulatory and technical materials and includes the following sections:

1. Short description design of the TGM-96 boiler unit.
1.1. Main parameters.
1.2. Boiler layout.
1.3. Combustion chamber.
1.3.1. Common data.
1.3.2. Placement of heating surfaces in the firebox.
1.4. Burner device.
1.4.1. Common data.
1.4.2. Technical characteristics of the burner.
1.4.3. Oil nozzles.
1.5. Drum and separation device.
1.5.1. Common data.
1.5.2. Intratympanic device.
1.6. Superheater.
1.6.1. General information.
1.6.2. Radiation superheater.
1.6.3. Ceiling superheater.
1.6.4. Screen steam superheater.
1.6.5. Convective superheater.
1.6.6. Steam flow diagram.
1.7. Device for regulating the temperature of superheated steam.
1.7.1. Condensing unit.
1.7.2. Injection devices.
1.7.3. Condensate and feedwater supply diagram.
1.8. Water economizer.
1.8.1. Common data.
1.8.2. Suspended part of the economizer.
1.8.3. Wall mounted economizer panels.
1.8.4. Convective economizer.
1.9. Air heater.
1.10. Boiler frame.
1.11. Boiler lining.
1.12. Cleaning heating surfaces.
1.13. Draft installation.
2. Extract from the thermal calculation.
2.1. Main characteristics of the boiler.
2.2. Excess air coefficients.
2.3. Heat balance and furnace characteristics.
2.4. Temperature of combustion products.
2.5. Steam temperatures.
2.6. Water temperatures.
2.7. Air temperatures.
2.8. Condensate consumption for injection.
2.9. Boiler resistance.
3. Preparing the boiler for starting from a cold state.
3.1. Inspection and testing of equipment.
3.2. Preparation of kindling diagrams.
3.2.1. Assembling circuits for warming up the reduced power unit and injections.
3.2.2. Assembling circuits for steam pipelines and a superheater.
3.2.3. Assembly of the gas-air duct.
3.2.4. Preparation of boiler gas pipelines.
3.2.5. Assembly of fuel oil pipelines within the boiler.
3.3. Filling the boiler with water.
3.3.1. General provisions.
3.3.2. Operations before filling.
3.3.3. Operations after filling.
4. Ignition of the boiler.
4.1. A common part.
4.2. Kindling on gas from a cold state.
4.2.1. Furnace ventilation.
4.2.2. Filling a gas pipeline with gas.
4.2.3. Checking the gas pipeline and fittings within the boiler for tightness.
4.2.4. Ignition of the first burner.
4.2.5. Ignition of the second and subsequent burners.
4.2.6. Blowing water indicator columns.
4.2.7. Boiler firing schedule.
4.2.8. Blowing the bottom points of the screens.
4.2.9. Temperature regime of the radiation superheater during kindling.
4.2.10. Temperature regime of the water economizer during kindling.
4.2.11. Connecting the boiler to the main line.
4.2.12. Raising the load to the nominal value.
4.3. Lighting the boiler from a hot state.
4.4. Ignition of the boiler using a boiler water recirculation scheme.
5. Maintenance of the boiler and equipment during operation.
5.1. General provisions.
5.1.1. Main tasks of operating personnel.
5.1.2. Regulation of boiler steam output.
5.2. Maintenance of a working boiler.
5.2.1. Observations during boiler operation.
5.2.2. Boiler power supply.
5.2.3. Controlling the temperature of superheated steam.
5.2.4. Control over the combustion mode.
5.2.5. Blowing the boiler.
5.2.6. Boiler operation using fuel oil.
6. Switching from one type of fuel to another.
6.1. Switching from natural gas to fuel oil.
6.1.1. Conversion of the burner from burning gas to fuel oil from the main control room.
6.1.2. Converting the burner from burning fuel oil to natural gas on site.
6.2. Switching from fuel oil to natural gas.
6.2.1. Conversion of the heater from burning fuel oil to natural gas from the main control room.
6.2.2. Converting the burner from burning fuel oil to natural gas on site.
6.3. Co-combustion of natural gas and fuel oil.
7. Stop the boiler unit.
7.1. General provisions.
7.2. Stop the boiler in reserve.
7.2.1. Actions of personnel during shutdown.
7.2.2. Testing of safety valves.
7.2.3. Actions of personnel after shutdown.
7.3. Boiler shutdown with cooling.
7.4. Emergency shutdown of the boiler.
7.4.1. Cases of emergency shutdown of the boiler due to protection or personnel.
7.4.2. Cases of emergency shutdown of the boiler by order of the chief engineer.
7.4.3. Remote shutdown of the boiler.
8. Emergency situations and the procedure for their liquidation.
8.1. General provisions.
8.1.1. A common part.
8.1.2. Responsibilities of duty personnel in case of an accident.
8.1.3. Actions of personnel during an accident.
8.2. Load shedding.
8.3. Station load shedding with loss of auxiliary needs.
8.4. Decrease in water level.
8.4.1. Signs of deterioration and actions of personnel.
8.4.2. Actions of personnel after liquidation of an accident.
8.5. Rising water level.
8.5.1. Signs and actions of personnel.
8.5.2. Actions of personnel in case of protection failure.
8.6. Failure of all water indicating devices.
8.7. Screen pipe rupture.
8.8. Superheater pipe rupture.
8.9. Water economizer pipe rupture.
8.10. Detection of cracks in pipelines and steam fittings of the boiler.
8.11. An increase in pressure in the drum of more than 170 atm and failure of the safety valves.
8.12. Stopping the gas supply.
8.13. Reducing fuel oil pressure behind the control valve.
8.14. Turning off both smoke exhausters.
8.15. Disabling both blower fans.
8.16. Disabling all RVPs.
8.17. Combustion of deposits in air heaters.
8.18. Explosion in the furnace or flue ducts of the boiler.
8.19. Torch breakage, unstable combustion mode, pulsation in the furnace.
8.20. Injection of water into the superheater.
8.21. Rupture of the main fuel oil pipeline.
8.22. A rupture or fire occurs in the fuel oil pipelines within the boiler.
8.23. Rupture or fire on main gas pipelines.
8.24. A rupture or fire occurs in gas pipelines within the boiler.
8.25. Decrease in outside air temperature below the calculated one.
9. Boiler automation.
9.1. General provisions.
9.2. Level regulator.
9.3. Combustion regulator.
9.4. Superheated steam temperature regulator.
9.5. Continuous blowdown regulator.
9.6. Water phosphating regulator.
10. Thermal protection boiler
10.1. General provisions.
10.2. Protection during boiler overfilling.
10.3. Protection when level is missed.
10.4. Protection when smoke exhausters or blowers are turned off.
10.5. Protection when all RVPs are turned off.
10.6. Emergency stop of the boiler with a button.
10.7. Fuel pressure drop protection.
10.8. Gas pressure increase protection.
10.9. Operation of the fuel type switch.
10.10. Protection against torch extinguishing in the firebox.
10.11. Protection for increasing the temperature of superheated steam behind the boiler.
11. Process protection and alarm settings.
11.1. Process alarm settings.
11.2. Process protection settings.
12. Pulse safety devices of the boiler.
12.1. General provisions.
12.2. Operation of IPU.
13. Safety precautions and fire prevention measures.
13.1. A common part.
13.2. Safety regulations.
13.3. Safety measures when taking the boiler out for repairs.
13.4. Safety and fire safety requirements.
13.4.1. Common data.
13.4.2. Safety requirements.
13.4.3. Safety requirements for boiler operation using fuel oil substitutes.
13.4.4. Fire safety requirements.

14. The graphic material in this AUC is presented in 17 drawings and diagrams:
14.1. Layout of the TGM-96B boiler.
14.2. Under the combustion chamber.
14.3. Screen pipe fastening unit.
14.4. Burner layout diagram.
14.5. Burner device.
14.6. Intratympanic device.
14.7. Condensing unit.
14.8. Diagram of a reduced boiler power supply and injection unit.
14.9. Desuperheater.
14.10. Assembling a circuit for warming up a reduced power supply.
14.11. Boiler firing diagram (steam path).
14.12. Boiler gas-air duct diagram.
14.13. Diagram of gas pipelines within the boiler.
14.14. Diagram of fuel oil pipelines within the boiler.
14.15. Furnace ventilation.
14.16. Filling a gas pipeline with gas.
14.17. Checking the gas pipeline for density.

Check of knowledge

After studying the text and graphic material, the student can launch a self-test program. The program is a test that checks the degree of assimilation of the instruction material. In case of an incorrect answer, the operator receives an error message and a quote from the instruction text containing the correct answer. The total number of questions for this course is 396.

Exam

After completing the training course and self-testing of knowledge, the student takes an examination test. It includes 10 questions automatically selected at random from among the questions provided for self-test. During the examination, the examinee is asked to answer these questions without prompting or the opportunity to refer to a textbook. No error messages are displayed until testing is completed. After finishing the exam, the student receives a protocol that sets out the proposed questions, the answer options chosen by the examinee, and comments on erroneous answers. The exam is graded automatically. The testing protocol is saved on the computer's hard drive. It is possible to print it on a printer.

The typical energy characteristics of the TGM-96B boiler 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.

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 for 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 made 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 . Coefficient useful action gross boiler and heat losses with flue gases are 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 exhaust 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 varying to 1.1 at 50% load based on thermal testing.

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 taken from 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 provide normal work boiler up to loads of 450 t/h.

2.2.9 . In total electrical power The mechanisms of the boiler installation include 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 steam and condensate consumption for 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 of boiler operation 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.

Explanation TGM - 84 - Taganrog gas-oil boiler, manufactured in 1984.

The TGM-84 boiler unit is designed according to a U-shaped layout and consists of a combustion chamber, which is an ascending gas duct, and a lower convective shaft, divided into two gas ducts.

There is practically no transitional horizontal gas duct between the firebox and the convective shaft. A screen steam superheater is located in the upper part of the firebox and the rotating chamber. In a convective shaft, divided into two gas ducts, a horizontal steam superheater and a water economizer are placed in series (along the flue gases). Behind the water economizer there is a rotating chamber with ash collection bins.

Two regenerative air heaters connected in parallel are installed behind the convective 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 half-fireboxes. The side and rear walls of the combustion chamber are shielded by evaporation 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 the distribution of pipes to equalize the pressure in the half-furnaces. The screen system is suspended from the metal structures of the ceiling using rods and has the ability to freely fall down during thermal expansion.

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

The combustion chamber is equipped with 18 oil burners, which are located on the front wall in three tiers.

The boiler has a drum with an internal diameter of 1800 mm. The length of the cylindrical part is 16200 mm. In the boiler drum, steam separation and washing with feed water is organized.

The superheater of the TGM-84 boiler is radiation-convective in nature and consists of the following three main parts: radiation, screen (or semi-radiation) and convective.

The radiation part consists of a wall and ceiling superheater.

Semi-radiation steam superheater made of 60 standardized screens.

The horizontal type convective superheater consists of two parts located in two gas ducts of the lower shaft 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 42x5.5 mm (item 12Х1МФ).

The inlet chamber of the ceiling superheater consists of two collectors welded together, forming a common chamber, one for each half-firebox. The outlet chamber of the ceiling superheater is one and consists of six 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 133x13 mm.

The convective superheater is made according to a z-shaped design, i.e. steam enters from the front wall. Each package consists of 4 single-pass coils.

Devices for regulating steam superheat temperature include: condensing unit and injection desuperheaters. Injection desuperheaters are installed in front of the screen superheaters in the screen section and in the convective superheater section. When the boiler is operating on gas, all desuperheaters operate; when operating on fuel oil, only the convective superheater installed in the cut-out.

The steel coil water economizer consists of two parts located in the left and right flue ducts of the convection shaft.

Each part of the economizer consists of 4 packages in height. Each package contains two blocks, each block contains 56 or 54 four-way coils made of pipes with a diameter of 25x3.5 mm (steel 20). 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 located outside the convective shaft.

The boiler is equipped with two regenerative rotating air heaters RVP-54. The air heater is placed outside and consists of a rotating rotor enclosed inside a stationary housing. The rotor rotates by an electric motor with a gearbox at a speed of 3 rpm. Reducing cold air suction into the air heater and air flows from the air to the gas side is achieved by installing radial and peripheral seals.

The boiler frame consists of metal columns connected by horizontal beams, trusses and braces and is used to absorb loads from the weight of the drum, heating surfaces, lining, service areas, gas ducts and other elements of the boiler. The frame is made welded from rolled profiles and sheet steel.

To clean the heating surfaces of the convective steam superheater and water economizer, a shot blasting unit is used, which uses the kinetic energy of freely falling pellets of 3-5 mm in size. Gas pulse cleaning can also be used.

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 specifications, layout and description of the design of the TGM-84 boiler and the principle of its operation. Drawings of the layout of the boiler unit with auxiliary equipment, a general view of the boiler and its components are given. 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 facilitated the operating conditions of the two-light screen pipes, which absorb the greatest amount of 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. Used on boilers gas-burners 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 with 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 the metal structures of the ceiling using rods 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 the pressure in the semi-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 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 create natural circulation of water in the boiler, cleaning and separation of steam produced in the screen pipes. The separation of the steam-water mixture of the 1st stage of evaporation is organized in the drum (the separation of the 2nd stage of evaporation is carried out on boilers in 4 remote cyclones), all the steam is washed 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 manifold of the 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 discharged through the distribution manifold into the drum under 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 design is double-flow with multiple mixing and transfer of steam across the width of the boiler, which makes it possible to equalize the thermal distribution 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 the rear wall of the 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. Stage III desuperheaters are installed between the upper and lower parts of the gearbox. 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 staggered with a pitch of 30 mm and 80 mm. The middle and upper blocks are installed on beams located in the flue. To protect against the 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. 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 a gas flow and cooling it in 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 (standard air suction is 0.2–0.25). BOILER FRAMEWORK The boiler frame consists of steel columns connected by horizontal beams, trusses and braces, and is used 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. The structure of the panels: 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 a 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 The 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 the “Technical requirements for explosion safety of boiler installations operating on fuel oil and natural gas”, as well as the current “Safety Rules for maintenance of 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. P. – 171. ________________________________________________________________________________________________________ State educational institution of higher professional education “Samara State Technical University” 432100. Samara, st. Molodogvardeyskaya, 244. Main building 12