Research on Ignition Characteristics of Nitrocellulose in Warehouse

Nitrocellulose was ignited by four most likely heat sources in the warehouse: incandescent bulb, overload conductor, melting droplet of conductor insulation skin and welding slag. The combustion characteristics of nitrocellulose were observed and recorded. The results showed that nitrocellulose was decomposed and burned instantaneously at 185.4°C.A small amount of nitrocellulose will not burn until it is attached to a 200W incandescent lamp. When the copper wire with the diameter of 2.5mm2 passes through an overload current of more than 2 times, the nitrocellulose will deflagrate. When nitrocellulose is ignited by open flame, it produces orange and yellow columnar flame, accompanied by a large number of floating sparks. When the nitrocellulose is ignited by the overload wire, it will deflate in the insulation skin, generating a large amount of flying sparks. Incandescent bulbs of 200W or above have the ability of igniting nitrocellulose. After nitrocellulose reaches 190°C, the reaction is basically complete and there is no flame burning. When the welding slag falls into nitrocellulose, it can ignite, and the combustion phenomenon is similar to that of open fire. Cigarette contact with nitrocellulose can ignite nitrocellulose. The main characteristic functional groups of nitrocellulost combustion products in infrared spectrum analysis include c-o expansion, symmetrical expansion of nitric acid and o–o of peroxide. The above experimental conclusions can provide technical support for the determination of nitrocellulose combustion in the process of fire investigation.