Abstract:

Under simulated real pipe network hydraulic conditions,the influences of low-concentration phosphate on the corrosion of carbon steel have been studied in the aspects of corrosion rate,iron releasing rate,and composition and morphology of corrosion products. It is found that the mass concentration of phosphate is 0.8 mg/L,the extreme value can be reached and the corrosion inhibition effect is the best. The corrosion rate of carbon steel could be reduced by 15.66%. Phosphate can inhibit the formation of γ-FeOOH and form phosphosiderite,making corrosion products more compact,so as to inhibit corrosion. The initial acceleration of iron release by phosphate may be an important reason for phosphate to promote the iron element to turn into stable iron oxide,so that the steady state of corrosion can be achieved earlier and finally the corrosion is inhibited.

Key words: phosphate, reclaimed water, corrosion

摘要：

在模拟真实管网水力条件下,从腐蚀速率、铁释放速率、腐蚀产物形貌及成分等方面研究了低浓度磷酸盐对碳钢腐蚀的影响。研究发现,磷酸盐为0.8mg/L时达到极值,腐蚀抑制效果最好,碳钢的腐蚀速率可降低15.66%。磷酸盐可抑制γ-FeOOH的形成,同时形成磷铁矿,使腐蚀产物更加致密,从而抑制腐蚀。磷酸盐对铁释放存在初期加速作用,可能是磷酸盐促进铁元素向稳定铁氧化物转变,使腐蚀提前达到稳定状态的重要原因,最终抑制腐蚀。

关键词: 磷酸盐, 再生水, 腐蚀

CLC Number: 

• TQ085+.4