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03125 Method and furnace for melting steel scrap
17
Process heating, power and incineration (energy applications in industry)
Energy consumption and utilization of waste heat 97103115 in zinc refining in China Zhang, L. Yvnse Jinshu. Yelian, 1996, (3). h-10. (In Chinese) The subject of this paper is the energy consumption and utilization of waste heat in zinc pyrometallurgy in China. The comprehensive energy/fuel consumption of the horizontal retort, vertical retort, 1SP. and hydrometallurgical processes were 4.65, 2.56, 2.124. and 2.289 tons standard coal per ton zinc, respectively. Forty per cent waste heat utilization was attained in some smelters. Energy inefficiency of Indian steel industry-scope 97103116 for energy conservation Choudhury, R. and Bhaktavatsalam, A. K. Enera Convers. Mgmr, 1997, 38, (2) 167-171. The steel industry is highly energy intensive. The specific energy consumption of Indian steel plants is typically quoted in the range of 3550 GJ/tcs compared to 17-25 GJ/tcs quoted for steel plants in advanced countries. The reasons for the low level of energy efficiency in Indian steel plants are analysed in this study. Amongst the various technological reasons, the poor quality of coking coal is identified to be the single most important factor for the energy inefficiency of Indian steel plants. The impact of the use of good quality coal on the overall specific energy consumption is evaluated. Experience with operation of a facility for preheat97103117 ing of air and gas in air heaters of blast furnace No. 4 in the Trinee Ironworks Kluza, 0. and Golasovky, L. Hum. Listy, 1996, 51, (12), 12-15. (In Czech) An evaluation of blast preheating by blast-furnace waste gas without addition of coke-oven gas or natural gas was made. The average blast temperature was <112O”C and the equipment satisfied the requirements. Use of the blast-furnace gas with a low calorific value required use of high flow rates in the burners. The arrangement was simple and required low maintenance. Furnace chamber apparatus for smelting of pig iron 97103118 using coal instead of coke Den H. and Huibert W. Eur. Pat. Appl. EP 754,766 (Cl. C21Bl3100), 22 Jan 1997, NL Appl. 101838, 19 Jul 1995, 7 pp. The replacement of the blast furnace with a cyclone and-converter type furnace using coal instead of coke in pig iron smelting is proposed. This furnace includes a metallization stage for Fe-ore feed, and coal combustion with oxygen to generate the hot gas for direct ore reduction The metallized ore is smelted in a pressurized vessel with combustion heating to manufacture the pig iron. Furnace for melting steel scrap and method for 97103119 melting Okumura, K. and Kasama, A. Jpn. Kokai Tokkyo Koho JIP 08,327,253 (96327.2531 (Cl. F27D3/14), 13 Dee 1996, Appl. 951137,020, 2 Jun 1995. 4 pp. (In Japanese) Some of gas inlet nozzles in an electric or converter-type furnace for melting steel scrap, are connected to the tapping opening. During scrap melting, a gas is blown through the opening so that temperature of the empty space inside the furnace reaches <1550”. General concept for the partial recovery of indus97103120 trial waste as a fuel for industrial boilers Khalatov, A. A. Prom. Teplotekh.. 1996, 18, (3), 80-85. (In Russian) Heat transfer and pressure drop in a heat exchan97103121 ger with a helical pipe containing inside springs Yildiz, C. et al. Energy Convers. &ml, 1997, 38, (6), 619-624. A heat exchanger constructed by placing spring-shaped wires with varying pitch within a helical pipe was considered. The pressure drop and the overall heat transfer rates were measured for the case of air flow at various Reynolds numbers inside and constant water flow outside. The results show that the Nusselt number increases with decreasing pitch/wire diameter ratio. Hot redox processing of zinc-containing ores and 97103122 wastes in electric-arc furnace for zinc recovery by vaporization Barcza, N. A. PCT Int. Appl. WO 97 00,333 (Cl. C22B19130), 3 Jan 1997, ZA Appl. 9514,963, 15 Jun 1995, 37 pp. A density-arc furnace was fed with Zn-containing ores, slag, and/or wastes premixed with a reductant and the volatilized Zn is recovered by condensation as Zn or crude Zn oxide. The operating conditions of the furnace are outlined and the process described. Influence of strength and reactivity of formed coke 97103123 on reaction, heat transfer and permeability in lower part of blast furnace Komaki, I. et al. Tetsu 10 Hanane. 1997, 83, (1) 12-17. (In Japanese) Two kinds of model experiment were conducted in order to establish the influence of formed coke properties on the phenomena in the lower part of the blast furnace. First, the influence of physical properties of formed coke on the deadman structure was investigated using a semi-circular model capable of simulating the heat transfer in the furnace. Second, the influence
256
Fuel and Energy Abstracts
July
1997
of strength and reactivity of formed coke on the reaction and permeability was investigated using a 90” sector model capable of simulating the reaction and heat transfer in the lower part of the furnace. The fine coke generation in the raceway can be suppressed and the permeability is kept stable by use of formed coke having higher strength at room temperature than normal coke, Due to the decrease of CO? gasification temperature and the increase of CO gas amount, the use of high reactive formed coke improves the reducing efficiency of the furnace. Liquid phase reduction process Flomelt 97103124 Vegman, E .F. Stal’ 1996, (I l), 63-68. (In Russian) This artilcle criticizes the liquid-phase pig iron manufacture in Romelt furnaces and contains erroneous data on the specific coal consumption and level of atmospheric toxic emissions. Method and furnace for melting steel scrap 97103125 Okumura, K. et al. Jpn. Kokai Tokkyo Koho JP 08311,525 [96.31 I.5251 (Cl. C21C5/52), 26 Nov 1996, Appl. 951114,875, 12 May 1995, 4 pp. (In Japanese) The paper describes an electric or top-blowing refining furnace for melting steel scrap. The melt is stirred with a gas hlown through >I opening provided in the furnace bottom and the scrap is melted by blowing oxygen and coal through a burner separator provided in the bottom. When a portion of the scrap is melted, the stirring gas is blown through the hurner. Method for manufacture of hot iron having very low 97103128 phosphorus content Nomura, M. ef al. Jpn. Kokai Tokkyo Koho JP 08,325.hlh [96.325,616] (Cl. C21B11102). 10 Dee 1996. Appl. 951135.144. 1 Jun lY95. 5 pp. (In Japanese) A shaft furnace having lower tuyeres and upper tuyercs is u\ed for the manufacture of low-phosphorous hot iron. A powdered feed containing 120% Fe oxide is intermittently injected through the upper tuyeres into the furnace by a hot blast containing oxygen. Natural gas. coke oven gas, or heavy oil is injected into the furnace through the lower tuyeres. and the temperature of the top gas is maintained at >700 C. 97103127 Method for molten-bath smelting Kawakami, M. et al. Jpn., Kokai Tokkyo Koho JP 09 3151 I [Y7 31,Sl I] (Cl. C21Bll/OO), 4 Feb 1997. Appl. 95/183.812. 20 Jul 199.5, 7 pp. (In Japanese) A converter type furnace is employed for molten bath smelting. This furnace has bottom tuyeres for injection of gas for stirring, tapping hole and slag discharge hole at the bottom, and metal cooling panels on the inner wall ~0.5 m above the molten iron level and in contact with slag. Iron ore, coal. and flux are directly charged into the molten bath for smelting under stirring by the gas injected from the hottom tuyeres. 97103128 Molten bath smelting with packed coke Kimura, K. et al. Jpn. Kokai Tokkyo Koho JP 08.31 1,515 [96,31 1.5151 (Cl. C21B11/02), 26 Nov 1996, Appl. 951115,500, 15 May 1995. 4 pp. (In Japanese) The procedure of molten bath smelting with packed coke is described. Metal oxide is blown with a hot blast into the furnace through lower and upper tuyeres and water vapour is blown into the packed coke at the level above the upper tuyeres for effective utilization of the sensible heat of top @IS.
97103129 New coke-manufacturing processes for blast furnaces Stuchlik, V. Nutn. &sty 1996, 51, (IO), 3-7. (In Czech) Newly-developed technologies for metallurgical coke manufacture are discussed. 97103130 Optimisation of a technical-economic model for use in cogeneration in industrial processes Arcuri, P. et al. Termotecnica, December l9Y6, (10). XI-8Y. The author claims the Net Present Value is maximized using this model, by means of an accurate comparison between the different types of plants. In addition to verifying the potential of the method, it IS applied to a milk production cycle and its derivatives. 97103131 Recent developments in COREX technology Eberle, A. et al. Proc. Annu. ht. Pirtshrqh Coal Conf., 1996, 13. (2), I IXX1193. The following are discussed: coals and iron ores suitable for the COREX Process, generation of direct reduced iron COREX gas, the use of hot metal in an electric arc furnace for steel manufacture, production cost comparison on the basis of l,OOO,OOOtoniyr. 97103132 Reed-grass contra oil, coal, and atomic energy Kubak, W. Prax. Natunviss., Chem., 1996, 45, (6) 35-39. (In German) The utilization of the reed grass Miscanthus giganteus. its specialty in photosynthesis, and its possible industrial use are outlined. A lecture demonstration was added.
Process heating, power and incineration (energy applications in industry)
Energy consumption and utilization of waste heat 97103115 in zinc refining in China Zhang, L. Yvnse Jinshu. Yelian, 1996, (3). h-10. (In Chinese) The subject of this paper is the energy consumption and utilization of waste heat in zinc pyrometallurgy in China. The comprehensive energy/fuel consumption of the horizontal retort, vertical retort, 1SP. and hydrometallurgical processes were 4.65, 2.56, 2.124. and 2.289 tons standard coal per ton zinc, respectively. Forty per cent waste heat utilization was attained in some smelters. Energy inefficiency of Indian steel industry-scope 97103116 for energy conservation Choudhury, R. and Bhaktavatsalam, A. K. Enera Convers. Mgmr, 1997, 38, (2) 167-171. The steel industry is highly energy intensive. The specific energy consumption of Indian steel plants is typically quoted in the range of 3550 GJ/tcs compared to 17-25 GJ/tcs quoted for steel plants in advanced countries. The reasons for the low level of energy efficiency in Indian steel plants are analysed in this study. Amongst the various technological reasons, the poor quality of coking coal is identified to be the single most important factor for the energy inefficiency of Indian steel plants. The impact of the use of good quality coal on the overall specific energy consumption is evaluated. Experience with operation of a facility for preheat97103117 ing of air and gas in air heaters of blast furnace No. 4 in the Trinee Ironworks Kluza, 0. and Golasovky, L. Hum. Listy, 1996, 51, (12), 12-15. (In Czech) An evaluation of blast preheating by blast-furnace waste gas without addition of coke-oven gas or natural gas was made. The average blast temperature was <112O”C and the equipment satisfied the requirements. Use of the blast-furnace gas with a low calorific value required use of high flow rates in the burners. The arrangement was simple and required low maintenance. Furnace chamber apparatus for smelting of pig iron 97103118 using coal instead of coke Den H. and Huibert W. Eur. Pat. Appl. EP 754,766 (Cl. C21Bl3100), 22 Jan 1997, NL Appl. 101838, 19 Jul 1995, 7 pp. The replacement of the blast furnace with a cyclone and-converter type furnace using coal instead of coke in pig iron smelting is proposed. This furnace includes a metallization stage for Fe-ore feed, and coal combustion with oxygen to generate the hot gas for direct ore reduction The metallized ore is smelted in a pressurized vessel with combustion heating to manufacture the pig iron. Furnace for melting steel scrap and method for 97103119 melting Okumura, K. and Kasama, A. Jpn. Kokai Tokkyo Koho JIP 08,327,253 (96327.2531 (Cl. F27D3/14), 13 Dee 1996, Appl. 951137,020, 2 Jun 1995. 4 pp. (In Japanese) Some of gas inlet nozzles in an electric or converter-type furnace for melting steel scrap, are connected to the tapping opening. During scrap melting, a gas is blown through the opening so that temperature of the empty space inside the furnace reaches <1550”. General concept for the partial recovery of indus97103120 trial waste as a fuel for industrial boilers Khalatov, A. A. Prom. Teplotekh.. 1996, 18, (3), 80-85. (In Russian) Heat transfer and pressure drop in a heat exchan97103121 ger with a helical pipe containing inside springs Yildiz, C. et al. Energy Convers. &ml, 1997, 38, (6), 619-624. A heat exchanger constructed by placing spring-shaped wires with varying pitch within a helical pipe was considered. The pressure drop and the overall heat transfer rates were measured for the case of air flow at various Reynolds numbers inside and constant water flow outside. The results show that the Nusselt number increases with decreasing pitch/wire diameter ratio. Hot redox processing of zinc-containing ores and 97103122 wastes in electric-arc furnace for zinc recovery by vaporization Barcza, N. A. PCT Int. Appl. WO 97 00,333 (Cl. C22B19130), 3 Jan 1997, ZA Appl. 9514,963, 15 Jun 1995, 37 pp. A density-arc furnace was fed with Zn-containing ores, slag, and/or wastes premixed with a reductant and the volatilized Zn is recovered by condensation as Zn or crude Zn oxide. The operating conditions of the furnace are outlined and the process described. Influence of strength and reactivity of formed coke 97103123 on reaction, heat transfer and permeability in lower part of blast furnace Komaki, I. et al. Tetsu 10 Hanane. 1997, 83, (1) 12-17. (In Japanese) Two kinds of model experiment were conducted in order to establish the influence of formed coke properties on the phenomena in the lower part of the blast furnace. First, the influence of physical properties of formed coke on the deadman structure was investigated using a semi-circular model capable of simulating the heat transfer in the furnace. Second, the influence
256
Fuel and Energy Abstracts
July
1997
of strength and reactivity of formed coke on the reaction and permeability was investigated using a 90” sector model capable of simulating the reaction and heat transfer in the lower part of the furnace. The fine coke generation in the raceway can be suppressed and the permeability is kept stable by use of formed coke having higher strength at room temperature than normal coke, Due to the decrease of CO? gasification temperature and the increase of CO gas amount, the use of high reactive formed coke improves the reducing efficiency of the furnace. Liquid phase reduction process Flomelt 97103124 Vegman, E .F. Stal’ 1996, (I l), 63-68. (In Russian) This artilcle criticizes the liquid-phase pig iron manufacture in Romelt furnaces and contains erroneous data on the specific coal consumption and level of atmospheric toxic emissions. Method and furnace for melting steel scrap 97103125 Okumura, K. et al. Jpn. Kokai Tokkyo Koho JP 08311,525 [96.31 I.5251 (Cl. C21C5/52), 26 Nov 1996, Appl. 951114,875, 12 May 1995, 4 pp. (In Japanese) The paper describes an electric or top-blowing refining furnace for melting steel scrap. The melt is stirred with a gas hlown through >I opening provided in the furnace bottom and the scrap is melted by blowing oxygen and coal through a burner separator provided in the bottom. When a portion of the scrap is melted, the stirring gas is blown through the hurner. Method for manufacture of hot iron having very low 97103128 phosphorus content Nomura, M. ef al. Jpn. Kokai Tokkyo Koho JP 08,325.hlh [96.325,616] (Cl. C21B11102). 10 Dee 1996. Appl. 951135.144. 1 Jun lY95. 5 pp. (In Japanese) A shaft furnace having lower tuyeres and upper tuyercs is u\ed for the manufacture of low-phosphorous hot iron. A powdered feed containing 120% Fe oxide is intermittently injected through the upper tuyeres into the furnace by a hot blast containing oxygen. Natural gas. coke oven gas, or heavy oil is injected into the furnace through the lower tuyeres. and the temperature of the top gas is maintained at >700 C. 97103127 Method for molten-bath smelting Kawakami, M. et al. Jpn., Kokai Tokkyo Koho JP 09 3151 I [Y7 31,Sl I] (Cl. C21Bll/OO), 4 Feb 1997. Appl. 95/183.812. 20 Jul 199.5, 7 pp. (In Japanese) A converter type furnace is employed for molten bath smelting. This furnace has bottom tuyeres for injection of gas for stirring, tapping hole and slag discharge hole at the bottom, and metal cooling panels on the inner wall ~0.5 m above the molten iron level and in contact with slag. Iron ore, coal. and flux are directly charged into the molten bath for smelting under stirring by the gas injected from the hottom tuyeres. 97103128 Molten bath smelting with packed coke Kimura, K. et al. Jpn. Kokai Tokkyo Koho JP 08.31 1,515 [96,31 1.5151 (Cl. C21B11/02), 26 Nov 1996, Appl. 951115,500, 15 May 1995. 4 pp. (In Japanese) The procedure of molten bath smelting with packed coke is described. Metal oxide is blown with a hot blast into the furnace through lower and upper tuyeres and water vapour is blown into the packed coke at the level above the upper tuyeres for effective utilization of the sensible heat of top @IS.
97103129 New coke-manufacturing processes for blast furnaces Stuchlik, V. Nutn. &sty 1996, 51, (IO), 3-7. (In Czech) Newly-developed technologies for metallurgical coke manufacture are discussed. 97103130 Optimisation of a technical-economic model for use in cogeneration in industrial processes Arcuri, P. et al. Termotecnica, December l9Y6, (10). XI-8Y. The author claims the Net Present Value is maximized using this model, by means of an accurate comparison between the different types of plants. In addition to verifying the potential of the method, it IS applied to a milk production cycle and its derivatives. 97103131 Recent developments in COREX technology Eberle, A. et al. Proc. Annu. ht. Pirtshrqh Coal Conf., 1996, 13. (2), I IXX1193. The following are discussed: coals and iron ores suitable for the COREX Process, generation of direct reduced iron COREX gas, the use of hot metal in an electric arc furnace for steel manufacture, production cost comparison on the basis of l,OOO,OOOtoniyr. 97103132 Reed-grass contra oil, coal, and atomic energy Kubak, W. Prax. Natunviss., Chem., 1996, 45, (6) 35-39. (In German) The utilization of the reed grass Miscanthus giganteus. its specialty in photosynthesis, and its possible industrial use are outlined. A lecture demonstration was added.