富氧燃烧辊道窑火焰空间的数值模拟研究-材料学专业论文.docxVIP

万方数据 万方数据 最后，模拟分析了富氧燃烧的节能减排效果，研究结果发现燃料量减少 10%、 20%、30%，辊道窑内烧成带的平均温度均有所下降。为了满足烧成所需温度， 2#辊道窑当采用 27%的富氧浓度时，最多可节能 20%。在此基础上，对 NOx 模 拟分析可知，NOx 浓度仍比空气助燃时高，但这仍能满足陶瓷生产对污染物 NOx 的排放要求。 关键词：辊道窑，富氧燃烧，数值模拟，流场，温度场 II Abstract Ceramic output of our country ranks first in the world. However, compared with western developed countries, there exist higher energy consumption, lower energy efficiency and more pollution problems that hinder the sustainable development of our ceramic industry. For this situation, it is urgent to achieve energy saving and emission reduction in the process of ceramic production. Oxy-fuel is considered as a relatively easy to implement energy-saving technology, which could speed up the burning, promote complete combustion of fuel, increase flame temperature, reduce gas emission and save energy. Currently, oxy-fuel technology has been successfully used in many fields such as glass, metallurgy. But it is not yet mature for the use of ceramic production, needed for further exploration and research. In the paper, two roller kilns of ceramics for daily use were researched. Three-dimensional geometric model of the combustion space was established and hexahedral mesh was generated. Then numerical simulation was preceded using CFD software Fluent. The Realizable k-ε turbulence model, eddy dissipation model, DO radiation model, gray gas weighted average model (WSGGM) and NOx pollutant model were selected to calculate. The characteristics of oxygen enriched combustion was researched and analyzed according to Fluent simulation results, which could provide the basis for the structural optimization of furnace and the promotion of oxy-fuel technology. The results showed as follow: Oxygen-enriched combustion could improve the combustion temperature of natural gas in roller kiln, but the flame was shorter and shrinking to the burner, causing the coverage of flame smaller. Therefore diameter of the burner should be adjusted according to the oxygen concentration to improve th