Development of a Novel Shaft Dryer for Coal-Based Green Needle Coke Drying Process

Abstract

Featured Application: The energy efficient and environmentally friendly shaft dryer can be applied for drying green cokes during the needle coke production process. Abstract:The industry of coal-based green needle coke develops rapidly in recent years. The green coke produced by the delayed coking process usually has a moisture content of 10%-25%, which damages the calcining kiln and needle coke quality. A standing dehydration tank is currently used to reduce the moisture content of green coke. However, this process has several weaknesses such as unstable operation, large land area occupation, and low productivity. To solve this issue, a novel drying system with a shaft dryer proposed in this work is suitable for green coke drying. Moreover, the performances of the green coke are investigated to design the proposed shaft dryer. The experimental result shows that the average vertex angle of the pile of green cokes is 109.2 • . The pressure drop of the dryer increases linearly with the green coke bed height, and the green coke with a larger size has a smaller pressure drop. The specific pressure drops are 5714, 5554, 5354, and 5114 Pa/m, with median green coke sizes of 26.85, 29.00, 30.45, and 31.80 mm, respectively. Tooth spacing is another important parameter which influences the mass of green coke leakage. The optimal tooth spacing and rotary speed of the rollers are determined by the required production yield.

Transformation of microstructure of coal‐based and petroleum‐based needle coke: Effects of calcination temperature

“…As is well known that, the quality of needle coke have a major influence on the performance of its derived graphite materials. Factually, the quality of needle coke mainly focuses on the properties of raw material (such as aromaticity, viscous flow characteristics, functional groups), liquid‐phase carbonization process, and calcinations process 21–24 . As reported in the references, 25 carbon microcrystalline transformation characteristics of needle coke at low temperature can provide important information to predict the graphitization ability at high temperature.…”

A Novel Rotary Dryer Filled with Alumina Ceramic Beads for the Treatment of Industrial Wastewaters: Numerical Simulation and Experimental Study

“…Besides, the motion trajectory of the ACBs in the airborne phase (Figure 1b) will also affect the installation of the inlet pipe, and thus influence the drying performance of the rotary dryer. Although plentiful studies have been done on the mixing process of the supplied materials, such as wood chips [26], cokes [27], and other agricultural products [28] in rotary dryers, there is little research about the motion of fillers in the rotary drum. As we know, the physical properties, such as density, hardness, and size of fillers are totally different from the supplied materials.…”

Thermogravimetric Determination of the Kinetics of Petroleum Needle Coke Formation by Decantoil Thermolysis

“…Decantoil from hydrotreated vacuum gas oil, obtained in fluid catalytic cracking (FCC) units, is by far the most demanded feedstock for petroleum-based needle coke production, although the rate of growth in the use of coal pitch is increasing. 7 The use of decantoil dates back to the discovery by Brooks and Taylor during the carbonization of petroleum feedstocks of an intermediate liquid crystalline phase (mesophase), 8 the formation of which is the first of two main stages due to which the formation of anisotropic needle coke is possible. 9 Decantoil is a heavy distillate feedstock with low sulfur and metal content, which consists of polycyclic aromatic hydrocarbons with 2−5 aromatic rings and has a low content of heptane-insoluble (HI) compounds.…”