Coking Technology Using Heavy Oil Residue and Hyper Coal

Abstract

Oil sand bitumen and hypercoal are examined as a caking additives to the mixture of strongly coking coal and non-slightly coking coal. Samples were coked, then their strength, crystallinity of the carbon structure, and an anisotropic microstructure were measured. Oil sand bitumen addition enhanced strength, but 15% addition caused a strength decline because of the formation of large pores and cracks. Hypercoal addition increased strength with increased its content. Correlation was observed between increased strength and the crystallinity of a carbon structure or the anisotropic microstructure. Results suggest that mutual melting occurred between a coal blend and a caking additive. Then the caking additive took a carbon structure with high crystallinity by coking, achieved a function as a binder material that connects coal-particle interfaces, and ultimately enhanced strength.

Effect of Carbonization Heating Rate on the Tensile Strength of Cokes Prepared from Chemically Upgraded Low Rank Coals

“…The soluble fraction contained THF, 1-MN solvent and 1-MN soluble coal fraction. 3,6,9,19,20,[25][26][27]32) As can be seen from the Fig. 1, in the case of THF wash approach, 1-MN soluble coal fraction and insoluble fraction are separated.…”

“…3,5,[6][7][8][9]27,29,31) They investigated the interactions between caking and slightly caking or non-caking coals using NMR analysis and H/C ratio and concluded that the binders (HPC) enhance the thermo-plasticity of the coal blend due to their high thermo-plasticity and overlapping thermoplastic temperature range with that of coals. 3,[19][20][21][23][24][25][26][27] Sakimoto et al introduced carbon matrix connectivity index to estimate the coke drum index which directly correlates with the coke strength. 3,29) They concluded that the addition of binders (HPC) increase the carbon matrix connectivity of the coke leading to increased coke strength.…”

“…The coke strength is strongly dependent on the pore structure and the carbon matrix which are affected by both the coking coal characteristics and the carbonization conditions. 12,13,[20][21][22][23][24][25][26] Development of the pore and the carbon structure during the carbonization process depends on the softening, melting and re-solidification characteristics of the coal. It also depends on the heating rate, heating pattern of carbonization and the maximum coking temperature.…”

Evaluation of the Structure and Strength of Coke with HPC Binder under Various Preparation Conditions

“…I D3 /I G ). 1) Table 2 summarizes the Raman parameters and its strength in the case of Tarrawonga coal, and photographs for the sample shape are shown in Fig. 3.…”

“…We have investigated the relationship between the macroscopic structure including caking property and strength, and the microscopic structure of coke by Raman spectroscopy. So far, we have found that hypercoal (HPC) showed the most good nature among various binders, 1) for which shows large number of polycyclic naphthenes or aromatic compounds, low ash content, high softening and melting property. HPC is produced by a solvent extraction of coal and sequential drying, and it includes much polycyclic naphthenes and aromatics, less ash, and has high softening and melting property.…”