【摘要】 在亚铵法制纸浆蒸煮过程中升温到120℃附近时,碳钢蒸球内壁将由活化转为钝化。钝化膜表层为亚硫酸亚铁铵结晶层,里层为铁的氧化物层。活化碳钢的表面大部份是疏松多孔的Fes层。对影响碳钢钝化的因素也进行了研究。根据碳钢在亚铵法蒸煮时的腐蚀特性,在纸厂现场试验了控制蒸煮液pH、设置防滑钉和快速升温等三种简易的防腐蚀措施,使用这些方法可使蒸球腐蚀率降到0.2mm/y以下。更多还原

【Abstract】 Conversion of the mild steel surface from active to passive state took place during heating of ammonium sulfite cooking. The results of surface analyses indicated that under passive conditions, a passive film was formed on the steel surface in ammonium sulfite liquors. The film consists of double layers, the outer layer being（NH₄）₂Fe（SO₃）₂·H₂O crystals; and the inner layer, iron oxide. Under active conditions,a loose mixture which was mostly FeS was formed on the steel surface. Several environmental effects on passivation were also investigated. Three simple corrosion prevention techniques were tried in the pulp mill, by which the corrosion rate of rotary spherical digester can be controlled under 0.2mm/y.更多还原