تحليل و مدلسازي ترموديناميكي كوره بلند به منظور افزايش راندمان

چكيده انگليسي :

Thermodynamic Modeling and Analysis of Blast Furnace to Improve Efficiency Hossein Fathi h fathi@me iut ac ir May 1st 2011 Department of Mechanical Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor A Saboonchi Prof ahmadsab@cc iut ac ir AbstractBlast furnace operation the most important process in iron making is improving in the world continuously Inblast furnace iron ores enter and are reduced by coke ignition The big problem in blast furnace operation isavailability of coke due to the high cost of this product In Iran this way of production iron is very common andthe coke of process is imported with high prices Despite of this fact that other fuels exist for blast furnaceoperation coke is the most popular fuel for that Therefore finding the ways to reduce coke consumption ratewith specific production of iron is needed In present study blast furnace operation is modeled by conservationequations of mass energy and availability which is useful for iron and steel industry According to thismodeling blast furnace is considered as a control volume with specific inputs and outputs Inputs and outputs ofthis control volume are selected by according to real operation of blast furnace In this project blast furnaceconditions are considered stable and steady state Based on used equations in modeling a simple computerprogram is created A comparison between actual operation of real blast furnace and model predictions iscreated Real data is derived from daily and monthly reports from blast furnace number 3 in iron and steelindustry in Isfahan The coke consumption rate and blast rate based on model results are calculated 3 16 and8 3 lower than real values respectively The first thermodynamic law of blast furnace is calculated 86 1 based on model predictions From energy conservation useful results is achieved in relation with energy inputand consumption but there is not any information about maximum useful reversible work of blast furnace Therefore availability conservation should be established According to results of availability conservation thesecond thermodynamic law of blast furnace is calculated 48 92 Moreover irreversibility of blast furnace isestimated 51 08 The high value of this irreversibility is due to ignition process in blast furnace A comparisonbetween availabilities of model results and the real data is established which shows good agreements with realconditions The results derived from model illustrate that by use of coke with lower ash rate of cokeconsumption and blast volume are decreased Also decrease of the reduced Silicon and reduce of Carbon andManganese in molten iron effect reduction influence on coke and blast rate Another parameter which isimportant in coke and blast rate is temperature and pressure of blast By increase of the temperature and pressureof blast the rate of coke consumption is reduced The rate of blast behaves the same Moreover if the volume ofnatural gas decreases coke consumption rate is reduced but it does not have significant effect on blast rate Slagvolume has the inverse effect on coke and blast rate decrease of slag volume will reduce the coke consumptionrate and blast rate Also by compressing blast the rate of blast will be reduced These operations concludeimprovement of thermal efficiency Key WordsBlast Furnace Modeling Thermal Efficiency Availability Fuel Consumption

فتحي، حسين

تحليل و مدلسازي ترموديناميكي كوره بلند به منظور افزايش راندمان

راندمان حرارتي , قابليت كاردهي , مصرف سوخت