GB/T 16508.6-2022 Shell boilers—Part 6:Combustion systems
1 Scope
This document specifies the technical requirements for combustion systems of shell boilers.
This document is applicable to combustion systems of shell boilers defined in the range of GB/T 16508.1, including:
a) The fuel inlet pipeline, air supply and induction system, and combustion equipment of liquid-and gas-fuel fired boilers as well as all the relevant control and monitoring equipment;
b) The feeding system (such as coal, biomass briquette, etc.), air supply and induction system, combustion equipment and dust (slag) removal device of solid fuel grate fired boiler as well as all the relevant control and monitoring equipment.
This document is inapplicable to combustion systems using pulverized coal and coal water slurry as fuels.
2 Normative references
The following documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 2900.48 Electrotechnical terminology of boilers
GB 11174 Liquefied petroleum gas
GB/T 13612 Manufactured gas
GB/T 16508.1 Shell boilers — Part 1: General requirements
GB/T 16508.5 Shell boilers — Part 5: Safety appurtenances and instruments
GB 17820 Natural gas
GB/T 18342 Commercial coal quality — Coal for travelling grate boiler
GB/T 24146 Rubber hoses and hose assemblies for use in oil burners — Specification
GB 25989 Fuel oils for burners
GB/T 36699 Specification for liquid fuels and gaseous fuels burners of boilers
GB/T 38753 Liquefied natural gas
GB 50041 Code for design of boiler plant
JB/T 3271 Specification for travelling grate stokers
NB/T 47034 Specification for industrial boilers
NB/T 47050 Technical specification for reciprocating grate
NB/T 47062 Biomass molded fuel fired boilers
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 2900.48 and GB/T 16508.1 and the following apply.
3.1
liquid fuel
natural organic fuel that is in liquid form under normal temperature and the liquid fuel obtained by processing the above natural organic fuel, such as light fuel oil, heavy fuel oil, and bio-oil
3.2
gaseous fuel
natural organic fuel or artificial fuel in the gaseous form under normal temperature and pressure, including natural gas, liquefied petroleum gas, coke oven gas, mixed city gas, blast furnace gas, converter gas, combustible industrial tail gas, hydrogen and biogas
3.3
solid fuel
solid fossil fuel and biomass fuel and the fuel obtained by processing, including coal of various qualities (bituminous coal, anthracite, lignite, etc.), biomass solid fuels, combustible solid wastes
3.4
flame detector
equipment used to detect the presence of flame and send signals to the control device
Note: It generally consists of sensing device and switching device.
3.5
ignition device
device used to ignite fuel in an ignition burner or main burner
4 Combustion systems of liquid and gaseous fuels
4.1 Type selection of fuel and burner
4.1.1 The natural gas shall meet the requirements specified in GB 17820. Liquefied natural gas, liquefied petroleum gas, manufactured gas, etc. shall meet the requirements of GB/T 38753, GB/T 11174, GB/T 13612 respectively.
4.1.2 Without impacting the safe operation of the burner, the liquid fuel shall reach the viscosity as required for its normal combustion at the burner inlet. The fuel oil shall meet the requirements of GB 25989.
4.1.3 Each boiler shall be equipped with an accumulator for fuel quantity, which may be configured during the design of boiler plant.
4.1.4 In the design or type selection of the burner, the boiler structure and parameters, fuel characteristics, flue gas resistance, excess air coefficient, pollutant emissions and other factors shall be considered, and they shall be adapted to the boiler load changes and the operating environment.
4.1.5 The burner equipped for the boiler shall meet the requirements of GB/T 36699. The following requirements shall be met during the type selection:
a) The actual output power of the burner shall be greater than or equal to the boiler thermal power divided by the boiler thermal efficiency;
b) The flame diameter and length of the burner shall match the combustion chamber size of the boiler.
4.1.6 When leaving the factory as an independent product, the random data of the burner shall include at least the following contents:
a) the drawings of product appearance and installation dimension;
b) electrical wiring diagram;
c) product operating instructions;
d) product certificate;
e) product type test certificate or inspection and spot check certificate (hard copy);
f) product packing list.
4.1.7 The burner operating instructions shall at least cover the following contents:
a) product design and working principle;
b) description of product performance (including burner operating curve or output thermal power range);
c) installation requirements;
d) a detailed description of the operating method;
e) instructions for maintenance;
f) warning and precautions.
4.2 Fuel inlet pipeline
4.2.1 The liquid fuel pipeline shall meet the following requirements:
a) Rigid tube should be adopted for the connection between the burner and the fixed fuel supply line; if rubber hoses and hose assemblies are adopted, they shall meet the requirements of GB/T 24146;
b) Strength test shall be carried out after the liquid fuel pipeline has been installed, and the test pressure shall be 1.3 times of the design pressure, but shall not be less than 0.5 MPa (gauge pressure);
c) The liquid fuel pipeline shall be equipped with a pressure release valve;
d) The automatic temperature control device as well as high and low fuel oil temperature interlock protection device shall be provided for the heavy fuel oil heater to ensure that the heavy fuel oil reaches the viscosity as required for the atomization of burner nozzle. If steam heating is adopted for heavy-fuel oil heating, the pipe section shall have safety protection measures;
e) The liquid fuel main pipe shall be provided with a manual rapid cut-off valve, which shall be installed in the site safe and convenient for operation;
f) The fuel pipeline shall be designed and arranged to meet the requirements of corrosion resistance as well as explosion and thermal expansion resistance in operating environment.
4.2.2 The gaseous fuel pipeline shall meet the following requirements:
a) The gas pipeline components shall be designed according to the gas supply pressure of the burner;
b) The gas burner and the gas pipeline should be connected with rigid tube; if the flexible hose made of non-metallic materials is adopted, it shall meet the requirements for pressure resistance of gas pipeline;
1 Scope
2 Normative references
3 Terms and definitions
4 Combustion systems for liquid and gaseous fuels
5 Laminar combustion systems for solid fuels