Cold And Hot State Experimental Studies Of Rotary Kilns And Numerical Simulation Of Petroleum Coke Calcinations

The calcinations of Petroleum coke is one of the main for producing pre-baked anode and graphite products. Petroleum coke calcinations in the rotary kiln are completed by high temperature heating. Though calcinations to exclude volatile and water to improve the density of carbonaceous materials, electrical conductivity, mechanical strength and chemical stability. Using rotary kiln for petroleum coke calcinations has its virtues, for example a large production capacity, less investment and wider adaptability to raw materials, product quality can be control easily and process production is realize the advantages of automatic control. At present, most of the large-scale production plants are using rotary kiln as petroleum coke calcinations equipment. The quality of calcinations process is a direct factor on the quality of the product quality, so how to improve the petroleum coke calcinations quality in rotary kiln is being concerned day by day. Based on the experimental study of hot and cold state of the petroleum coke in rotary kiln and the numerical simulation of the calcinations in rotary kiln, this paper get the best operating parameters for rotary kiln, so that to enhance the quality of calcined petroleum coke and reduce the burn rate of petroleum coke, and it is very necessary and feasible.This paper describes the cold state experiments of petroleum coke in rotary kiln, experiments are conducted on pilot rotary kiln with a cylindrical discharge dam. Experimental results indicate that the hold-up shows a near-linear increase with the mass of feed per kiln rotation, and MRT increase slightly with the feed rates and MRT decreases sharply with the rotation speeds. The experimental results are used to text the equations provided by other researchers. Comparisons show that, the numerical model of Saeman agrees well with the measurements, for the errors are less than 8 percent. So the numerical model of Saeman can be used for calculating the average residence time. In this paper, computational fluid dynamics software FLUENT is also used for simulating. The simulations is use for predict the molar density of unburned gas at outlet, and it is used under different conditions such as different locations of tertiary air; different length which are into the kiln of secondary air tube and tertiary air tube. At last, get the suitable location of tertiary air and the best length which are into the kiln of secondary air tube and tertiary air tube for 50m×1.8m kiln. The article also detailed describes the hot state experiments of petroleum coke in rotary kiln. Experiment is mainly divided into two phases: pre-drying kiln phase and the calcinations phase after input petroleum coke. Thought measuring the temperatures of the seven different points at different times, obtained the temperature distribution curve along the rotary kiln and the axial length of the belt. The conclusions of experiment match well with the industrial rotary kiln.