Needle coke is a high quality variety in developing carbon material, its porous solids which appearance is silver and metallic, and the structure has obvious flow texture, the hole is big, little and slightly oval, particles have a larger length-width ratio, to walk with a fibrous or needle-like texture, it feels lubricated. Needle coke is the raw material for production of UHP electrode, special carbon materials, carbon fiber and its composites such as high-end carbon product. According to the different raw materials, needle coke can be divided into two kinds: oil series needle coke and coal series needle coke. Produced from petroleum residue is oil series needle coke; produced from coal tar pitch and its fraction is coal series needle coke.
Carbon calcining rotary kiln is one of the key equipments in needle coke production. The structure and operation process of needle coke rotary kiln directly affect the quality and production cost of needle coke products, and the calcination temperature and temperature distribution are important factors affecting the calcination quality.
The combustion process inside the rotary kiln is actually a very complicated turbulent flow and combustion chemical reaction process. The flow is a typical turbulent and gas-solid two-phase multicomponent flow. Heat transfer includes convection heat transfer, radiation heat transfer and heat conduction. Combustion involves solid particles and gas phase combustion. Particle combustion has surface liquid evaporation, particle volatilization, particle oxidation and so on.