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With the internationalization of the steel market, China's iron and steel enterprises facing heavy pressure, technological innovation become the only way for enterprises to improve their competitiveness. The blast furnace technology is today's iron and steel enterprises with coal coke, reduce production costs, to achieve sustainable development of the technology of choice. Anthracite, meager lean high metamorphic coal due to the high carbon content, fat high-calorie, low-price, pulverizing security advantages become the first choice of pulverized coal injection material, and dominant in the total of pulverized coal injection. But the gasification reactivity, high ignition temperature, burning ember performance defects and poor limit its large-scale application in the blast furnace environment. For such a high degree of metamorphism, active coal to the coal modified in order to increase the amount of pulverized coal injection, reducing the the coke ratio has become one of the hot spots of the research and development of the steel industry. This paper to simulate blast furnace ironmaking conditions, catalytic combustion experimental study of the sodium salt of the alkali metal. Reached the following conclusions: (1) With the added amount of change, different the different catalytic combustion effect. NaCl, Na 2 CO 3 , of NaNO 3 preferred addition amount of respectively 0.5%, 1.0%, 0.5%, NaClO 3 catalysis increase as the addition amount increased; (2) at the same time within the combustion, volatiles analyze the greater the speed, the better the effect of catalytic combustion. Catalytic Combustion of volatiles in decreasing order in NaClO gt; the of Na 2 CO 3 gt; a of NaCl gt; NaNO 3 ; (3) Catalytic Combustion within a certain time of the thermal decomposition product of the presence status affecting the persistence of the effect of the catalytic combustion. The Catalytic Combustion catalytic effect persistence order of NaClO 3 gt; the NaCl gt; NaNO 3 gt; the of Na 2 CO . Based on the combined results of the preliminary study of Research and the experimental results, development the Catalytic Combustion DCS1 low volatile coals DCS2, DCS3, using thermal gravimetric analysis (TG / DTG) combustion kinetics studies explore the catalytic combustion mechanism. The results show that: the DCS1, DCS2, DCS3, so ignition temperature of the raw coal T 1 drop of 33 ° C, 41 ° C, 64 ° C, reduced burning time in the 15s, 80s, 135s, half peak width ΔT 1/2 reduced 5 ° C, 30 ° C, 45 ° C, the burning ember temperature T h reduced 24 ° C, 27 ° C, 24 ° C; apparent activation energy E reduces 15.90%, 3.45%, 21.26%, combustion characteristics index increased 19.40%, 7.46% and 11.94%, respectively. Catalytic Combustion of PCI coal in pulverized coal combustion process thermochemical changes directly affect the catalytic combustion effects. Using DCS1 Xiangtan Steel Blast Furnace for Catalytic Combustion industrial test. The test results show that the: DCS1 the ratio of 0.453% (mass ratio), lower coke rate (including coke) 6.84kg / t of iron, tons of iron costs decreased by 12.3 yuan, the generation of coal coke, increase the amount of pulverized coal injection, saving cost and intended purpose.
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