Study On The Basic Characteristics And The Optimization Of Coal Blending Structure Of LY STELL Coking Plant Coking Coal

The coking coal is abundant in our country,but fat coal and coking coal is scarce. With the aim to use coking coal resources rationaly and reduce raw material costs, in the paper, taking coking coal that used for the actual production in LY STEEL coking coal plant's as object, we analyzed its basic properties, technological properties, petrography characteristics and the ability of holding inert component. And single coals and coke coking coal blending experimental test were conducted. Further to evaluate single coal coking properties and replacement of different coal. And conducted blending optimization, in this paper, with the aim to research the relationship between the chemical structure and the caking property of three different coking coal processed at different temperatures, solvent extraction and the infrared analysis were used, The results were shown as follows:?1? The technological properties of different rank coking coals were quite different. 1/3 coking coal caking index?average of 81.76? is higher than the coking coal?average of 78.40?, in heating process, they could produce a certain quantity of gum body and the plastic temperature range of 1/3 coking coal and coking coal respectively was 72?<?t<106? and 54?<?t<114?, the log MF value of 1/3 coking coal?mean of 3.75? is higher than coking coal?mean of 2.38?; in heating process, best bondability of fat coal can produce quite quantity gum body which have good fluidity, the log MF values of fat coal are greater than 4 and its plastic temperature range is 361?⁴89?, these fat coal have a wide plastic temperature range??t>108??. The bondability of lean coal was worst, almost no gum body.?2? The results of solvent extraction, infrared spectrum analysis showed that extraction rate in CS2/THF mixture solvent increased with processing temperature. Extracts contain mainly aliphatic hydrocarbons and carboxyl and other oxygen-containing functional groups, some of the heavy components and aromatic structures in coal exists in the residue; the solvent extraction flow rate of coal processed temperature within the temperature range between the plastic and Gieseler showed a good degree of positive correlation and the correlation coefficient is r=0.875.?3? The results of coking coal blending showed that the coke quality are different between different alternatives 1/3 coking coal. when Huainan 1/3 coking coal substitute Datun 1/3 coking coal, the coke quality significantly reduced(CRI and CSR were changed from 27.8% to 30.4% and from 59.4% to 52.5%; M₄₀ and M₁₀ were changed from 81% to 77.2% and 7.9% to 8.2%). The same proportion of different 1/3 coking coal on coke quality is in this order: 1/3 Pingxiang coking coal> 1/3 Datun coking coal > 1/3 Huainan coking coal. When fat coal was substituted by 1/3 coking coal, the quality of coke had a slight decline, in the same proportion of other coal, the coal coke quality reduced greatly when Wancheng fat was substituted by 10% proportion of 1/3 Huainan coking coal(CRI and CSR were reduced from 27.8% to 27.0% and from 59.4% to 56.6%; M₄₀ and M₁₀ were reduced from 81% to 78.2% and 7.9% to 8.3%), which still met the requirements of blast furnace coke. So the alternative is feasible.?4? The basic properties of coal can be used to predict the coke quality, a prediction model is: M₄₀=-0.182 V_daf +0.313G-1.079 A_d +75.308, r=0.9094?n=8? M₁₀=0.0709V_daf-0.102G-0.00397 A_d +14.556, r=0.7829?n=8? CRI=4.128V_daf–1.018G+1.857 A_d +15.021, r=0.9132?n=8? CSR=-5.091 V_daf +1.926G-0.558 A_d +34.343, r=0.8589?n=8??5? Compared with the original coal blending scheme, under the same coke quality, when the blending ratio is 24%1/3JM, 15%FM, 55%JM and 6%SM, blending raw material costs relativly to a minimum.