The Designand Simulation Of Oxygen-Enriched Inferior Coal Burner For Rotary Cement Kiln

At present our country is facing extremely severe energy and environmentsituation, however the cement production is one kind of industry with high energyconsumption and high pollution. There are some difficulties in ignition and keepingcombustion stability using low grade inferior fuel. Oxygen enriched technology canreduce f ignition temperature greatly, therefore reduce the coal quality effectively,shorten the burn-out time of pulverized coal, increase the combustion efficiency,make burning much more stably and completely, realize energy-saving objective. Theface that cement rotary kiln using low grade inferior coal as the main fuel increasesenergy conservation and emission reductions, and develops circular economy, andtherefore bring huge economic and environmental benefits.The following are several aspects of a detailed study on the above problems.First of all, study the cement production process in-depth and do themaltheoretical calculation exactly. With the foundation of the study on rotary kilnpulverized coal burning process, design the software named "coal combustiontemperature prediction and rotary kiln design prediction software", which providetheoretical guidance for the design and renovation of oxygen enriched burner incement rotary kiln.Second, study the static combustion characteristics of the different grade fuel indifferent oxygen concentration with thermogravimetric method. With oxygenconcentrations increasing, the TG curves of pulverized coal move to low temperaturearea. The biggest burn rate increases and appears earlier, and the ignition temperatureand burn-out temperature reduce significantly, and the coal samples ignite andburn-out much more easily. The oxygen concentration has significate effect onburn-out temperature. With the increasing oxygen concentration, ignition and burningtime reduce, however this trend slow down when oxygen concentration is more than40%. The particle size of pulverized coal has significant influence on combustioncharacteristics. The bigger the particle size is, the greater the influence is.Third, equip oxygen enriched bypass to the original burner in the cement rotarykiln. The transformed burner system consists of the original four channel burner, richoxygen channel, oxygen system and affiliated piping system. The oxygen channels ofoxygen enriched burner are made of industrial ceramic material which ensures thesafety of the burner. Use the valve in the opening inlet to adjust oxygen rate, so as tomeet the need of cement production process conditions.Fourth, from the numerical simulation of oxygen enriched burner combustion inrotary cement kiln which burns inferior coal, we know that the burner can formreasonable velocity field and temperature field in other words flame shape by means of adjusting certain parameters. The oxygen-enriched combustion technologyusing inferior coal in the rotary kiln can increase the adiabatic flame temperature inorder to meet the cement production temperature. It can also reduce the air and gasquantity significantly and predicte the relationship between combustion pollutantsgeneration and oxygen concentration theoretically, and provide reference andguidance for the design and production operation of practical oxygen enriched burnerfor rotary cement kiln which uses low grade inferior fuel.