SO_(2)气氛下316L合金纤维滤袋的气固腐蚀特性

Gas-solid corrosion characteristics of 316L alloy fiber fabric in SO_(2) atmosphere

高温除尘领域,316L合金纤维滤袋由于可重复利用性引起广泛关注,但316L合金纤维材料的气固腐蚀特性及机理尚不明确,成为实际应用中的风险因素。基于316L合金纤维滤袋的气固腐蚀特性,采用固定床模拟腐蚀试验,研究SO_(2)气氛下316L合金滤料的腐蚀行为,分析腐蚀后滤料的过滤性能及力学性能变化,探究SO_(2)浓度和烟气组分(O_(2)、H_(2)O)对其腐蚀特性的影响,并结合腐蚀前后滤料微观形貌以及元素分布,研究腐蚀机理。结果表明,316L合金纤维滤料的整体腐蚀程度低,腐蚀周期内腐蚀增重率最大为2.30 mg/g,主要体现为局部腐蚀,表面点蚀坑内观察到Mn、S元素的富集,局部质量分数达21.28%、13.08%;SO_(2)浓度变化对腐蚀反应的影响较弱,O_(2)对腐蚀过程的影响主要体现在腐蚀初期的氧化反应,对整体腐蚀进程的促进作用很小,H_(2)O对于腐蚀反应具有显著的抑制作用;腐蚀后滤料透气度和孔结构稳定性保持良好,开孔隙率降至小于5%,而材料屈强比显著提高,抗振性能显著下降。

In the field of high-temperature dust removal,316 L alloy fiber fabric has attracted widespread attention due to its reusability.However,the gas-solid corrosion characteristics and mechanism of 316 L alloy fiber materials are not clear,which has become a risk factor in practical applications.Based on the gas-solid corrosion characteristics of 316 L alloy fiber fabric,a fixed bed simulation corrosion experiment was used to study the corrosion behavior of 316 L alloy filter materials under SO_(2) atmosphere,and analyze the filter performance and mechanical properties of the filter after corrosion.The influence of SO_(2) concentration and flue gas components(O_(2),H_(2)O) on its corrosion characteristics was studied.And the microscopic morphology and element distribution of the filter material before and after corrosion were combined to study the corrosion mechanism.The results show that the overall corrosion degree of the 316 L alloy fiber filter material is low,and the maximum corrosion gain rate during the corrosion cycle is 2.30 mg/g,which is mainly reflected in local corrosion.The enrichment of Mn and S elements is observed in the surface pits and the local content is 21.28% and 13.08%.The change of SO_(2) concentration has a weak influence on the corrosion reaction,and the influence of O_(2) on the corrosion process is mainly reflected in the oxidation reaction at the initial stage of corrosion,which has little promotion of the overall corrosion process.H_(2)O has a significant inhibitory effect on the corrosion reaction.The air permeability and pore structure stability of the filter material remain good after corrosion,the porosity decreases by less than 5%,while the flexural ratio of the material is significantly improved and vibration resistance is significantly reduced.