GB 19081-2025 Safety specification for dust explosion prevention in feed processing system
1 Scope
This document specifies the division and scope of explosive dust hazardous areas in feed processing systems, as well as the general requirements, requirements for buildings (structures), requirements for process systems and equipment, electrical requirements, requirements for dust removal and pneumatic conveying systems, requirements for explosion control measures, and requirements for operational safety management of feed processing systems, and also describes the corresponding verification methods.
This document is applicable to the design, operation, and safety management of feed processing systems that involve combustible dust explosion hazards.
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 12158 General requirements for preventing electrostatic accidents
GB 15577 Safety regulations for dust explosion prevention and protection
GB/T 15604 Terminology for dust explosion prevention and protection
GB/T 15605 Specifications for pressure venting of dust explosion
GB/T 26888 Grain and oil machinery - Magnetic separator
GB/T 37241 Guide on inerting for the prevention of explosions
GB 50016 Code for fire protection design of buildings
GB 50057 Code for design protection of structures against lightning
GB 50058 Code for design of electrical installations in explosive atmospheres
GB 55037 General code for fire protection of buildings and constructions
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 15604 and the following apply.
3.1
feed processing
process of converting feed materials into finished or semi-finished feed products through specific processing technology and equipment
3.2
feed processing system
system comprising several feed processing equipment arranged into various processing sections according to process requirements, assembled within a building (or structure)
3.3
feed dust
solid tiny particles of feed that can settle in the air due to their own weight but can also remain suspended in the air for a period of time
Note: Including feed additives.
3.4
silo
vertical cylindrical enclosed structure for storing bulk granular materials
3.5
feed processing workshop
workshop for processing feed materials into feed products
3.6
hazardous area (dust)
area in which combustible dust, in the form of a dust cloud is present, or may be expected to be present, in quantities such as to require special precautions for the construction, installation and use of equipment
Note 1: Hazardous areas are divided into zones based upon the frequency and duration of the occurrence of explosive dust atmospheres (see GB/T 3836.35, 6.2).
Note 2: The potential hazard of creating an dust cloud from a dust layer also needs to be considered.
[Source: GB/T 3836.35-2021, 3.9]
3.7
Zone 20
a place in which an explosive dust atmosphere, in the form of a dust cloud in air, is present continuously, or for long periods or frequently
[Source: GB/T 3836.35-2021, 3.25.1]
3.8
Zone 21
a place in which an explosive dust atmosphere, in the form of a dust cloud in air, is likely to occur in normal operation occasionally
[Source: GB/T 3836.35-2021, 3.25.2]
3.9
Zone 22
area in which an explosive dust atmosphere, in the form of a dust cloud in air, is not likely to occur in normal operation but, if it does occur, will persist for a short period only
Note: The potential of creating an explosive dust cloud from a dust layer also needs to be considered.
[Source: GB/T 3836.35-2021, 3.25.3]
4 Division and scope of explosive hazardous areas for feed dust
4.1 The areas subject to dust explosion hazards in feed processing systems shall be divided into Zone 20, Zone 21, and Zone 22 based on the frequency and duration of the occurrence of explosive feed dust atmospheres.
4.2 The division and scope of explosive hazardous areas for feed dust shall be determined based on conditions such as processes, material characteristics, location of source of feed dust release, quantity and possibility of dust release, explosion conditions, ventilation and dust removal, and structure and layout of the areas. An example of area division is provided in Annex A.
4.3 When changes occur in processes, materials, equipment, structure and layout of areas, or work organization methods, the scope and level of explosive dust hazardous areas shall be re-evaluated, defined, and divided.
4.4 Throughout the duration of the entire operation, documentation on the division and description of zones shall be maintained, and the hazardous nature of the process and the zones shall be dynamically evaluated on a regular basis.
4.5 When changes occur in the classification and scope of explosive hazardous areas for feed dust, technical and management measures shall be promptly taken to ensure that equipment and facilities within the changed area meet the requirements for dust explosion prevention.
Contents Foreword III 1 Scope 2 Normative references 3 Terms and definitions 4 Division and scope of explosive hazardous areas for feed dust 5 Overall requirements 6 Requirements for buildings (structures) 6.1 General requirements 6.2 Ground 6.3 Walls 7 Requirements for process systems and equipment 7.1 General requirements 7.2 Bucket elevator 7.3 Chute 7.4 Screw conveyor and scraper conveyor 7.5 Bin discharger 7.6 Magnetic separation equipment 7.7 Grinder 7.8 Batching scale, mixer, and surge hopper 7.9 Heating device 8 Electrical requirements 8.1 General requirements 8.2 Electrical equipment 8.3 Electrical wiring 9 Requirements for dust removal and pneumatic conveying systems 10 Requirements for explosion control measures 10.1 General requirements 10.2 Venting 10.3 Inerting 10.4 Flameproof 11 Requirements for operational safety management 12 Verification methods Annex A (Informative) Examples of division of explosive dust hazardous areas in feed processing systems Bibliography
