This standard specifies the basic principles and requirements that should be followed in the design of flue-type waste heat boilers. This standard is effective for water pipe and tube type fixed waste heat boilers with water as the medium, rated steam pressure not greater than 3.82MPa, and rated steam temperature not greater than 450℃. For fixed waste heat boilers with rated steam pressure greater than 3.82MPa and less than 5.88MPa, and rated steam temperature not greater than 450℃, this standard can be used as a reference. This standard does not apply to direct-flow waste heat boilers, heat pipe waste heat boilers and hot water waste heat boilers. JB/T 7603-1994 Design Guidelines for Flue-Type Waste Heat Boilers JB/T7603-1994 Standard Download Decompression Password: www.bzxz.net

Mechanical Industry Standard of the People's Republic of China
JB/T7603-94
Design Guidelines for Flue-type Waste Heat Boiler
Published on December 9, 1994
Implemented on June 1, 1995
Subject Content and Scope of Application
Cited Standards·
General Provisions
Overall Layout of Waste Heat Boiler.
Materials·
Calculation Principles of Waste Heat Boiler
Structural Design Principles.
Furnace Wall·
Cleaning of Heating Surface
Main Accessories and Instruments·|| tt||Gradually record A Simple thermal calculation method for waste heat boilers.......(1)
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Standard of the Machinery Industry of the People's Republic of China
Design Guidelines for Flue-type Waste Heat Boilers
1 Subject Content and Scope of Application
JB/T7603-94
This standard specifies the basic principles and requirements that should be followed in the design of flue-type waste heat boilers (hereinafter referred to as "waste heat boilers"). This standard applies to water-tube and smoke-tube fixed waste heat boilers with water as the medium, a rated steam pressure not exceeding 3.82MPa, and a rated steam temperature not exceeding 450℃. For stationary waste heat boilers with a rated steam pressure greater than 3.82MPa and less than 5.88MPa and a rated steam temperature not greater than 450℃, this standard can be used as a reference. This standard does not apply to direct-flow waste heat boilers, heat pipe waste heat boilers and hot water waste heat boilers. 2 Reference standards
GB1048
GB1300
GB1348
GB1576
GB3077
GB3087
GB4241
GB4242
GB5117
GB5118
GB5310
GB5676
GB6654
GB8163
GB9222
GB9439
GB9440
GB10864
GB11943
GB12145
High quality carbon Technical conditions for cable structure steel
Carbon cable structure steel
High quality carbon structure steel hot rolled thick steel plate and wide steel strip Carbon purple steel and low alloy steel plate for boiler
Carbon cable steel hot rolled round steel for standard parts
Stainless steel welding rod
Nominal pressure of pipeline components
Welding wire
Ductile iron castings
Water quality standard for low pressure boilers
Technical conditions for alloy structure steel
Seamless steel pipes for low and medium pressure boilers
Stainless steel wire rods for welding
Stainless steel wire for welding
Carbon steel welding rods
Low alloy steel welding rods
Seamless steel pipes for high pressure boilers
Casting carbon steel for general engineering
Carbon steel and low alloy steel welding rods for pressure vessels Alloy steel thick plate seamless steel pipe for conveying fluid
Strength calculation of pressure components of water tube boiler
Gray cast iron
Forgeable cast iron
Parameter series of waste heat boiler
Boiler drawing
Water quality standard of thermal power generating unit and steam power equipment Load code of building structure
Design code of steel structure
Approved by the Ministry of Machinery Industry in 1994-12-09
Implementation on 1995-06-01
Unified standard of building structure design
GBJZ11
JB2192
JB3622
JB5339
JD17601394
Masonry of industrial furnace Specification for construction and acceptance of the project Square cast iron economizer tubes and elbows
Strength calculation of pressure components of shell boilers
Standard for seismic design of boiler frames
Product model compilation method for flue-type waste heat boilers ZBJ98017
JB/Z201
Design guidelines for internal devices of industrial boilers
Hydrodynamic calculation method for power station boilers
JB/T5341Technical documents and main contents of flue-type waste heat boilers 3 General provisions
The design of waste heat boiler protection shall comply with the "Interim Regulations on Safety Supervision of Boiler Leli Containers" and its implementation rules and the "3.1
Regulations on Safety Technical Supervision of Steam Boilers"
Product model compilation of waste heat boilers shall be carried out in accordance with the provisions of 2BJ98017. 3.23
The parameters of waste heat boilers can be selected in accordance with GB10864. 3.3
Waste heat boiler drawing shall be carried out in accordance with GB11943. Design drawings and technical documents shall comply with JB/T5341. Strength calculation of waste heat boiler receiving components shall be carried out in accordance with GB9222 and JB3622 respectively. Waste heat boiler design scope:
Waste heat boiler flue gas inlet and outlet connection devices: pipelines within the scope of waste heat boiler, including main steam valve, water supply operation table, safety valve, drain valve, blowdown valve, vent valve, etc.; auxiliary combustion device, cooling chamber, cold ash hopper; boiler drum, water-cooled wall, superheater, evaporation heating surface, economizer, etc., ash cleaning and ash removal device:
Waste heat boiler steel frame, platform, escalator, etc., furnace wall and guard plate.
3.8 When designing a waste heat boiler, it is necessary to understand the production process of the main industrial furnace and other waste heat source equipment, master the changing rules of the flue gas volume, flue gas density, flue gas composition, etc. entering the waste heat boiler, and study the physical and chemical evolution process of the smoke dust composition, concentration, and particle size in the flue gas, select a reasonable waste heat boiler structure, and at the same time, understand the overall layout of the industrial furnace and other waste heat source equipment (including the civil structure of the plant) in order to design an overall layout that meets the requirements. 3.9 When the waste heat boiler is an integral part of the main equipment during operation, the waste heat boiler design should ensure that the main equipment can operate safely and continuously under various design conditions. Its continuous operation time should be able to adapt to the major and medium maintenance period of the biological equipment. When the waste heat boiler is only used as a waste heat recovery method and can be separated from the main equipment without affecting the safe production of the main equipment, the waste heat boiler design should pay attention to economic rationality while ensuring the safe and reliable operation of its main body, and strive to minimize the metal weight and reduce the equipment cost. 3.10 According to the dust content in the inlet flue gas of the waste heat boiler and the characteristics of the flue gas, the waste heat boiler is divided into five categories: the waste heat boiler with dust content of no more than 20g/m3 is defined as the first category of waste heat boilers; a.
The waste heat boiler with dust content in the flue gas is greater than 20g/m\ and not more than 70g/m3 is defined as the second category of waste heat boilers; b.
The waste heat boiler with dust content in the flue gas is less than 70g/m* is defined as the third category of waste heat boilers; c.
The waste heat boiler with adhesive smoke dust in the flue gas is defined as the fourth category of waste heat boilers; e. The waste heat boiler with strong corrosive components or toxic smoke in the flue gas is defined as the fifth category of waste heat boilers. Note: "m\ refers to the gas volume at 0.1013MPa and 0℃, the same below. 3.11 Waste heat boilers generally adopt natural circulation. In various situations such as large evaporation volume, large fluctuation of heat load, high dust content in flue gas, rapid startup requirements of waste heat boilers, control of exhaust gas temperature and compact dimensions of waste heat boilers, etc., forced circulation or natural 2
circulation and forced circulation can be selected.
JB/T7603-94
3.12 Waste heat boilers are generally designed for indoor layout. When waste heat boilers are arranged in the open air or semi-exposed, anti-corrosion, anti-freezing, lightning protection, rain protection, wind protection and other measures should be taken.
3.13 Whether the waste heat boiler needs to be equipped with auxiliary combustion stacks should depend on the operating rate of the industrial furnace, the changes in flue gas volume and flue gas temperature, the requirements of steam temperature and steam balance, and It depends on the fluctuation and demand of the steam load of the thermal system. When there is no requirement for the steam volume and steam supply reliability, auxiliary combustion device may not be installed.
3.14 When the waste heat boiler is equipped with an auxiliary combustion device, its auxiliary fuel should be the same fuel as the industrial furnace. The combustion system should be able to meet the requirements of the waste heat boiler to operate continuously and stably within the minimum and maximum design load range. 3.15 The feed water temperature of the waste heat boiler is generally divided into three levels: 20C, 60C and 105, and can be determined separately when necessary. The feed water quality shall comply with the provisions of GB1576 and GB12145.
3.16 When determining the design pressure of the waste heat boiler, in addition to the wide application requirements, attention should be paid to the phenomenon of S2 in the flue gas being converted into SO2. The tube wall temperature of the evaporating heating surface should be higher than the dew point temperature of sulfuric acid vapor in the flue gas, and the difference is generally not less than 20°C. 3.17 When there are strict requirements on the superheat of superheated steam, the waste heat boiler should be equipped with a steam desuperheater. If necessary, an external superheater can also be installed. 3.18 Except for the process system that has special requirements on the exhaust temperature, the exhaust temperature of other waste heat boilers (9ps>) can be designed according to the following regulations; D (evaporation capacity) <10t/h, p≤250℃; D (evaporation capacity) ≥101/h, ≤220℃. For small waste heat boilers that use smoke for natural ventilation, the rear heating surface may not be provided, but the exhaust temperature (p) should not be greater than 320℃. 3.19 When the flue gas entering the waste heat boiler has the possibility of explosion, the waste heat boiler should be equipped with a The explosion-proof door should have a fixed number of doors and a sufficient area. There should be no less than two explosion-proof doors, and the total explosion-proof area should not be less than 0.2m. The discharge port of the explosion-proof door should not endanger personal safety, and the explosion-proof port should be led to the outside when necessary.
3.20 If the parts of the waste heat boiler that need to be frequently operated (such as water level gauge, soot blower, safety valve, peephole, etc.) cannot be operated on the ground or operating platform, an operating platform access platform and escalator should be provided. The height of the center of the operating part from the operating platform is generally 1~-1.5 m.
3.21 The escalator should be an inclined escalator. The angle between the escalator and the horizontal plane should be 45°~50°. If the layout is difficult, the angle can be appropriately increased, but it should not exceed 70°
3.22 Mechanized technology should be used for ash cleaning and slag removal of waste heat boilers. Automated technology should be used for water supply operations. 4 Overall layout of waste heat boilers
4.1 The type of waste heat boiler can be selected according to the following principles:. The first type of waste heat boiler can adopt the structural type of water pipe or smoke pipe type waste heat boiler; b, For the second type of waste heat boiler, the heating surface generally adopts finned tubes or smooth tubes. When using smooth tubes, the flue gas can be flushed horizontally or obliquely, but the horizontal and vertical pitch of the tube should be appropriately increased to avoid smoke bridging. If the smoke has good flow performance and the flue gas does not cause serious wear on the tube, the flue gas flow rate can be increased to enhance the self-ashing capacity. c. For the third and fourth types of waste heat furnaces, multi-flue furnaces or straight-through furnaces with smoke settling chambers or radiation cooling chambers should be used. The flue should be equipped with a cold ash hopper. The heating surface of this type of waste heat boiler should adopt Finned tubes or membrane walls. Anti-wear measures should be taken at the parts of the heating surface that are prone to wear.
d. In addition to selecting the type of waste heat boiler protection structure according to the smoke concentration, the fifth type of waste heat boiler should also use steel plate closed furnace wall 4.2 Smoke pipe waste heat boiler generally includes boiler shell, front smoke box, smoke pipe, rear smoke box and other components. 4.2.1 Smoke pipes generally use pipes with Dw51~89nm. 4.2.2 The number and thickness of the tensioning pipes should be determined based on strength calculations. 4.3 The first type of water tube waste heat boiler has evaporation heating When the tube bundle heating surface is used, the flue gas should be flushed horizontally. 4.4 When the superheater is arranged in the convection flue, the heating surface can be arranged vertically or horizontally, and the flue gas should be flushed horizontally. When finned tubes are used, the heating surface should be arranged vertically, and the flue gas can also be flushed longitudinally. 3
JB/T7603-94
4.5 When the steel tube economizer is arranged in the convection flue: it is generally arranged horizontally, and the flue gas is flushed horizontally. When the economizer is arranged vertically, the highest position of its outlet header should be equipped with an exhaust device.
4.6 The waste heat boiler should be equipped with sufficient door holes of various types. 4.7 The heating surface of the waste heat boiler should be equipped with a ash cleaning device. The first type of waste heat boiler should be equipped with a ash cleaning device. 4.8 Auxiliary combustion device of waste heat boiler
4.8.1 The auxiliary combustion device of the waste heat boiler can be designed to be combined with the waste heat boiler or independently set. 4.8.2 When the combined auxiliary combustion device is required to have good regulation performance within the load range of 0-100%, no water-cooled wall may be provided in the combustion chamber. 4.8.3 Independent auxiliary combustion devices generally adopt natural ventilation, which is mainly used for external superheaters. 4.9 The radiation cooling chamber of the waste heat boiler should be able to reasonably organize the dynamic field of the flue gas so that the flue gas temperature can be reduced to 100-150℃ below the smoke solidification point when the flue gas enters the rear flue.
4.10 The heating surface of the radiation cooling chamber should adopt a membrane wall or finned tube structure, and the superheater heating surface can also be arranged on the ceiling and side wall of the radiation cooling chamber.
4.11 The flue gas can enter the radiation cooling chamber or the smoke settling chamber from the top or front of the radiation cooling chamber or the smoke settling chamber. When the flue gas enters from the top, the smoke velocity can be 8-20m/s; when the flue gas enters from the front, the smoke velocity is generally 3-8m/s. 4.12 For the flue gas entering from the front of the radiation cooling chamber or the smoke settling chamber, the smoke velocity in the chamber is generally 2-6m/s. For the flue gas entering from the top of the radiation cooling chamber or the smoke settling chamber, the smoke velocity in the chamber is generally 1-3m/s. The radiation cooling chamber or the smoke settling chamber should have sufficient length in the depth direction of the flue gas flow so that the smoke dust can be gradually solidified and settled during the flow process.
For corrosive or toxic flue gas, a membrane wall structure should be used. 4.13
There are three types of waste heat boiler furnace walls: heavy furnace walls, light furnace walls, and pipe laying furnace walls. 4.14
a. For waste heat boilers of the first, second, and third categories, light furnace walls should be used; b. For waste heat boilers with an evaporation capacity of less than 4t/h, heavy furnace walls can be used. For waste heat boilers with high requirements for furnace wall tightness or inferior to the fifth category, membrane wall tube furnace walls should be used. c.
The following factors should be considered in the arrangement of beams, columns and braces of the waste heat boiler frame: 4.15
The structure of the auxiliary combustion chamber and cooling chamber;
The arrangement of each section of the heating surface and its support requirements: b.
The arrangement of all doors, holes and ash cleaning devices: c.
d. The support of the furnace wall and guard plate.
5 Materials
5.1 The metal materials and welding rods, welding wires, welding fluxes used in the pressure components of the waste heat boiler shall comply with the relevant national standards and industry standards. Material manufacturing must ensure the quality of the materials and provide a quality certificate. Metal materials and weld metals should have the specified strength, toughness and elongation under the conditions of use, as well as good fatigue resistance and corrosion resistance. 5.2 The metal materials used for the pressure components of the waste heat boiler should be selected according to the provisions of Table 5-1, Table 5-2, Table 53, Table 54, Table 5-5 and Table 56 respectively.
Table 5-1 Steel plate
Scope of application
Type of steel
Carbon steel
Low alloy steel
Technical standard
Working pressure
MPa(kgf/cm\)
≤5.88(60)1)
≤5.8(60)
Type of steel
Low alloy steel
14MnMoVg
18MnMoNbg
JB/T7603-94
Continued Table 5-1
Technical standard
When manufacturing boilers that are not subject to radiant heat, the working pressure is not limited. Note: 1)
Table 5-2
Types of steel
Low alloy
Note, 1)
10, 20
15CrMo
12Cr1MoV
12MoVWBSiXt
12Cr2MoWVTiB
12Cr3MoVSiTiB
Technical standards
GB3087
GB5310
GB5310
GB5310
GB5310
|GB5310
GB5310
Heating surface pipes
Steam pipes, headers
Heating surface pipes
Heating surface pipes
Heating surface pipes
Heating surface pipes
Heating surface pipes
Heating surface pipes
Heating surface pipes
The service life is required to be within 20 years,
which can be increased to 450℃,
when oxidation loss is taken into account in the strength calculation, 620C can be used. Table 5-3 Forged carbon steel low alloy Note: 1) Q235-A 20, 25 12CrMo 15CrMo 12Cr1MoV Technical standards GB3077 GB3077 GB3077 Forged carbon steel low alloy Forgings exposed to radiant heat, working pressure is unlimited, flanges, flange covers, hand hole covers, forgings not in contact with flames, large forgings, hand hole covers, header end covers, flanges, large plated parts, large forgings, fire-type forgings, working pressure MPa (kgf/em) <5.88(60)
≤5.88(60)
≤5.88(60)
Applicable scope
Working pressure
MPa(kgf/cm*)
≤5.88(60)
Applicable scope
Working pressure
MPa(kgf/cm*)
≤2.45(25)
≤5.88(60))
≤450
Types of steel
Carbon steel
ZG200--400
ZG230+450
JB/T7603-
Table 5-4 Steel castings
Technical standards
GB5676
GB5676
Note: ①Hollow pressure castings shall be subjected to water pressure test in accordance with GB1048. ③For steel castings with medium temperature exceeding 450℃, heat-resistant alloy steel shall be used. If the nominal pressure is greater than 6.27MPa, impact toughness shall also be required. 1)
Scope of application
Nominal pressure
MPa(kgf/em*)
≤6.27(64)
Nominal pressure is unlimited"
Table 5-5 Cast iron parts
Scope of application
Name of cast iron
Gray cast iron
Forgeable iron
Ductile iron
Note:?
Not less than
KTH300--06
KTH330--08
KTH350-10| |tt||KTH370-12
QT400-18
Technical standards
GB9439
GB9440
GB1348
Gray cast iron shall not be used for drain valves and drain elbows. Cast iron nominal diameter
≤300
≤200
≤150
Medium working pressure
MPa(kgf/cm)
≤0.78(8)
≤1.27(13)||tt ||≤1.57(16)
≤1.57(16)
≤2.45(25)
Medium temperature
For boilers with rated steam pressure less than or equal to 1.27MPa (13kgf/cm2) and superheaters with steam temperature less than or equal to 300℃, the valve shells of the drain valve and the sewage valve can be made of malleable cast iron or ductile iron in the table. Square braided iron economizer tubes and elbows of waste heat boilers with rated steam pressure less than or equal to 1.57MPa are allowed to use gray cast iron with a grade not less than HT150 and manufactured according to JB2192 Square cast iron economizer tubes and elbows for waste heat boilers with rated steam pressure less than or equal to 2.45MPa are allowed to be manufactured in accordance with JB2192 using grey cast iron with a grade not less than HT200. In the manufacturing plant, the cast iron parts used on the economizer shall be subjected to a water pressure test, and the pressure shall be equal to 2.5 times the working pressure of the waste heat boiler. Repair welding is not allowed for castings used in pressure-bearing parts. The eccentricity of the iron parts shall not exceed the requirements of the drawings. Table 5-6 Fasteners
Scope of application
Type of steel
Q235-A
Technical standards
GB 699
Studs and bolts
Studs and bolts
Studs and bolts
Working pressure
MPa(kgf/cm*)
≤1.57(16)
≤1.57(16)
Medium temperature
Type of steel
Alloy steel
5.3 Bracing parts
30CrMa
25CrMoVA
JB/T7603-9 4
Continued Table 5-6
Technical Standards
GB3077
Studs and Bolts
Studs and Bolts
Studs and Bolts
Scope of Application
Working Pressure
MPa(kgf/cm*)
Medium Temperature
The steel used for the bracing parts of waste heat boilers must be killed steel and shall comply with the provisions of GB715 or the provisions of No. 20 steel in GB699. Plate bracing parts shall be boiler steel.
5.4 Welding Wire and Electrode
The welding rod used for welding pressure components shall comply with the provisions of GB5117, GB5118 and GB983. The welding wire shall comply with the provisions of GB1300, GB4241 and GB4242.
5.5 Before the development of new steel grades for waste heat boiler pressure parts, technical assessments must be conducted by relevant units in the metallurgical, manufacturing, use, labor, and standard departments.
5.6 Steel plates and steel pipes used as substitutes for waste heat boiler pressure components shall use boiler-specific steel with similar chemical composition and mechanical properties, in addition to complying with the following provisions. When using steel materials that are not included in national standards, professional standards, or departmental standards, the substitute unit shall submit technical basis to the provincial labor department for approval.
5.6.1 For waste heat boilers with a rated steam pressure of less than or equal to 0.39 MPa, Q235-A in GB700 can be used instead of 20g in GB713 for pressure components that do not come into contact with flames.
5.6.2 For waste heat boilers with a rated steam pressure of less than or equal to 0.39 MPa, No. 15 steel and No. 20 steel in GB711 can be used instead of 20g in GB713.
5.6.3 For waste heat boilers with rated steam pressure less than or equal to 0.39MPa, the 10# steel and 20# steel in GB8163 can be used to replace the 10# steel and 20# steel in GB3087.
5.6.4 For waste heat boilers with rated steam pressure less than or equal to -1.27MPa, the 20R and 16MnR in GB6654 can be used to replace the 20g and 16Mng in GB713 respectively after the aging impact value is qualified. 6 Calculation principles of waste heat boilers
When designing waste heat boilers, thermal calculations, flue gas dynamic calculations, pressure component strength calculations and safety valve discharge calculations should be carried out. If necessary, hydrodynamic calculations and steel frame calculations should also be carried out. 6.1 Thermal Calculation
6.1.1 In addition to the provisions of this standard, it is recommended to adopt the "Standard Method for Thermal Calculation of Boiler Units" (published by China Machinery Industry Press in 1976). For the thermal calculation of low-pressure waste heat boilers with small flue gas volume, the calculation method listed in Appendix A can be used. 6.1.2 Calculation of flue gas volume and flame
6.1.2.1 Flue gas volume
The flue gas volume is calculated as follows:
V,=V,+△aV,+Ve+Vb,
Where: V,-total flue gas volume, m*/h; JB/T7603-94
V,, the flue gas volume entering the waste heat boiler, m\h; Aa——the air leakage coefficient of the waste heat boiler, when there is no actual measurement, it can be selected by referring to Table 6-1, for the slightly positive pressure waste heat boiler, △α=0; Vthe volume of the sootblowing medium, m/h
Vb-the flue gas volume generated by the auxiliary combustion device, m3/h, the waste heat boiler has no auxiliary combustion device V=0. Since the waste heat boiler is generally intermittent sootblowing, the flow rate of the sootblowing medium can be ignored. When a large number of sootblowers are used in a large waste heat boiler and they are in continuous operation, the flow rate of the sootblowing medium should be considered. Table 6-1 Air leakage coefficient of each part of the waste heat boiler
Part name
Radiation cooling chamber
Convection section
Membrane water-cooled wall with metal guard plate
Water-cooled wall with double-layer metal guard plate
Water-cooled whole belt single-layer metal guard plate
Water-cooled wall, brick furnace wall without guard plate
Slag condensation pipe, screen superheater, Yanfa heating surface (D》50t/h) Evaporation heating surface (D≤50t/h)
Superheater
D>50 t/h
Economizer
D≤50 t/h
Cast iron, with guard plate
Cast iron, without guard plate
Note: The air leakage coefficient value in the table is the value when the flue gas negative pressure entering the waste heat boiler is 100Pa. 6.1.2.2 Heat of flue gas
The air leakage coefficient △α
of flue gas is expressed by the heat carried by each standard cubic meter of flue gas entering the waste heat boiler. For the flue gas of the third type of waste heat boiler, the melting of the smoke entering the waste heat boiler should also be taken into account. The flame of the flue gas of the waste heat boiler is expressed by the following formula: =++Aα
Where: I,Total flue gas heat, kJ/m\;kJ/m2
I', one by one the flame of flue gas, for the case of auxiliary combustion, it is the flame of smoke after mixing, kJ/mI-smoke flame, kJ/m~;
Iin-- for cold air, kJ/m.
The flame of flue gas is equal to the sum of the heats of each component in the flue gas. See the following formula: I'Ic2+Is02+2+I02+Ico+IH20+
(6--2)
Where: Icoz, Iso2, I, lo2, IHao-are the heats of COz, SOz, Nz, Or, CO, H, O, .... and other gases in the flue gas, kJ/m. The melting point of each component gas in the flue gas is calculated according to the following formula: I.-V.· C,· t.
Wherein: I - the melting point of a certain gas in the flue gas, kJ/m\: V. -..The volume of a certain gas in the flue gas, m\/m\kJ/m
-The constant-pressure specific heat of a certain gas in the flue gas at temperature tg, kJ/m, ℃, see Table 6-2; C.
tg-The temperature of the flue gas at a certain point, ℃The melting point of smoke is calculated according to the following formula:
I- 0. 8μ· Ch · th
Where: Ih—specific heat of smoke, kJ/m;
0.8——coefficient;bzxZ.net
Smoke content, kg/m
Smoke temperature, ,
JB/T7603-94
Cn—~specific heat of smoke, kJ/kg·℃. In the absence of exact data, C can be generally taken as 0.5862. Table 6-2 Average specific heat of air and flue gas components (average constant pressure specific heat C under 1 atmosphere) (kJ/m℃) Temperature
Heat balance of waste heat boiler
The heat balance calculation of waste heat boiler is to balance the heat entering the waste heat boiler with the sum of effectively utilized heat and various losses, and calculate the steam production of the waste heat boiler and the utilization rate of the waste heat boiler accordingly. 6.1.3.1 Heat balance equation:
Q=Q+Q+Q+Q.+Q+Q
Where: Q is the heat entering the waste heat boiler, kJ/h; Q1 is the effectively utilized heat of the waste heat boiler, kJ/h; - exhaust heat loss, kJ/h,
Q is the heat loss of chemical incomplete combustion, kJ/h, Q. Mechanical incomplete combustion heat loss, kJ/hQs is the heat dissipation loss, kJ/h,
Q. - ash discharge heat loss, kJ/h.
The heat entering the waste heat boiler is calculated as follows: Q'=Q+Q+Qh+Qu
Where; Q——
The heat brought in by the flue gas, kJ/h; (may include the flame value of the smoke) Q—The radiation heat from the furnace mouth of the industrial furnace, kJ/hkj/h
Poei9o++poe9oeereree
(6—6)
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