火力发电厂煤和制粉系统防爆设计规程
1 范围
本标准规定了燃煤火力发电厂煤的输送、贮存、煤粉制备及其相关烟、风道等粉尘爆燃的防爆设计基本要求。
本标准适用于燃煤火力发电厂煤及制粉系统及其围包体(如原煤仓、煤粉仓、粗细粉分离器以及筒仓等)内煤粉云的爆燃。煤与燃油混烧或煤与可燃气体混烧的火力发电厂有关煤的部分应遵照本标准。
本标准不适用于由于外部火焰或暴露于其他火源中而产生过大内压的围包体，如有关锅炉燃烧室和锅炉燃烧系统的防爆要求，也不适用于爆轰和无的爆嫌(如室外爆炸或蒸汽云爆炸)。
2 规范性引用文件
下列文件中的条款通过本标准的引用而成为本标准的条款。凡是注日期的引用文件，其随后所有的修改单(不包括勘误的内容)或修订版均不适用于本标准，然而，鼓励根据本标准达成协议的各方研究是否可使用这些文件的最新版本。凡是不注日期的引用文件，其最新版本适用于本标准。
GB/T 126 粉尘云最大爆炸压力和最大压力上升速率测定方法
GB 50058 爆炸和火灾危险环境电力装置设计规范
DL/T 435-2004 电站煤粉锅炉燃烧室防爆规程
DUT 466-2004 电站磨煤机及制粉系统选型导则
DL 5000 火力发电厂设计技术规程
DUT 5035-2004 火力发电厂采暖通风与空气调节设计技术规程
DUT 5121-2000 火力发电厂烟风煤粉管道设计技术规程
DUT 5145-2002 火力发电厂制粉系统设计计算技术规定
3 术语和定义
3.1 基本概念
3.1.1 煤自燃倾向性 coal spontaneous ignition tendency
表征煤自燃难易的特性。煤的自燃倾向性与煤的吸氧量、含水量、全硫含量以及粒度等特性有关。煤的自燃倾向性根据煤的吸氧量和全硫含量不同可分为如表3.1.1所示的三个等级。
3.1.2 惰性气体 inert gas
致使系统中可燃物质不能维持燃烧的不燃烧、不反应气体。
3.1.3 围包体 enclosure
围包煤或煤粉的物体，分为房间、建筑物、容器、设备或管道等。
3.1.4 原煤仓 raw coal bunker
贮存原煤的围包体。
3.1.5 筒仓 cylindrical silo
作为混煤设施、运煤系统缓冲设施和贮煤设施的圆筒形围包体。
3.1.6 煤粉仓 pulverized coal bin
贮存煤粉的围包体。
1 Scope
This standard specifies the basic requirements of explosion prevention design for coal conveying, storage and pulverized coal preparation of coal-fired power
plant, as well as such design for relevant flue, air duct and dust ignition.
This standard is applicable to coal and pulverized coal preparation system of coal-fired power plant, as well as explosion and ignition of pulverized coal cloud in enclosure (such as raw coal bunker, pulverized coal bin, coarse and fine pulverized coal separator as well as cylindrical silo etc.). For coal-fired power plant using multi-fuel ignition of coal and fuel oil or that of coal and fuel gas, it shall comply with this standard for contents related to coal.
This standard is not applicable to enclosure that produces extremely large internal pressure due to external flame or being exposed to other ignition source. If there are explosion prevention requirements of boiler furnace and boiler ignition system, it is not applicable to detonation and unconditional explosion and ignition.
2 Normative References
The following documents contain provisions which, through reference in this standard, constitute provisions of this standard. For dated reference, subsequent amendments to (excluding corrections), or revisions of, any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the documents. For undated references, the latest edition of the normative document referred to applies.
GB/T 126 Determination for Maximum Explosion Pressure and Maximum Rate of Pressure Rise of Dust Cloud
GB 50058 Electrical installations design code for explosive atmospheres and fire hazard
DL/T 435-2004 Code for the Prevention of Pulverized Coal Firing Furnace Explosions in Power Plant Boilers
DL/T 466-2004 Guide for Type Selection for Pulverizers and Pulverizing Systems of Power Station
DL 5000 Technical Code for Designing Fossil Fuel Power Plants
DL/T 5035-2004 Technical Code for Heating Ventilation and Air Conditioning
Design of Fossil Fuel Power Plant
DL/T 5121-2000 Technical Code for Design of Thermal Power Plant Air & Flue Gas Ducts/ Raw Coal & Pulverized Coal Piping
DL/T 5145-2002 Technical Code for Design and Calculation of Pulverized Coal Preparation System of Fossil-fired Power Plant
3 Terms and Definitions
3.1Basic conception
3.1.1 Coal spontaneous ignition tendency
It refers to characteristic of difficult degree of coal spontaneous ignition. Coal spontaneous ignition tendency is related to coal's oxygen uptake capacity, moisture capacity, total sulfur content as well as granularity and other
characteristics. According to difference of coal's oxygen uptake capacity and total sulfur content, spontaneous ignition tendency may be divided into three grades as showed in table 3.1.1
3.1.2 Inert gas
It refers to incombustible gas without reaction, and it makes combustible material in system be unable to maintain burning.
3.1.3 Enclosure
It refers to objects enclose coal or pulverized coal, such as room, building, container, facility or pipeline.
3.1.4 Raw coal bunker
It refers to enclosure used to store raw coal.
3.1.5 Cylindrical silo
It refers to cylindrical enclosure used as coal-blending facility, cushioning facility of coal-transporting system and coal-storing facility.
3.1.6 Pulverized coal bin
It refers to enclosure used to store pulverized coal.
