摘要
石油天然气工业的耐蚀合金(CRAs)设计要考虑腐蚀产物的稳定性。通过电位—pH图,以及FeCO3、氧化物和硫化物溶解度的计算,评价了在CO2 /H2S环境中钢铁表面生成的腐蚀产物的稳定性。在CO2 的环境中,碳钢的局部腐蚀与腐蚀产物FeCO3 的形成有关。含有铁素体-珠光体显微结构的J55钢可以耐CO2 腐蚀,是因为层状渗碳体可以稳固表面形成的腐蚀产物。铬钢是CO2 环境中的耐蚀材料,因为表面能生成黏附性非晶铬氧化物的腐蚀产物。当H2S的含量超过CO2 的分压为100×10 6时的对应含量时,从腐蚀产物FeCO3 和FeS的稳定性来看,其腐蚀就变成H2S的腐蚀类型。在H2S环境中,耐蚀合金腐蚀产物的稳定性与铬的氧化物和硫化物(如FeS,Ni3S2 和MoS2 )的生成有关。
The corrosion resistant alloys(CRAs)for oil and gas industry is carried out to consider the stability of corrosion products. The stability of corrosion products is evaluated by potential-pH diagram,calculated-solubility of FeCO 3,oxides and sulfides and analysis of corrosion products which are formed on steel surface in CO 2 and/or H 2S environments.Severe localized corrosion of carbon steels in CO 2 environments relates to the formation behavior of FeCO 3 corrosion products.J55 steel with feritic-pearlitic microstructure mitigates the CO 2 corrosion,because the lamellar cementite helps to anchor the corrosion products.Cr steels are corrosion resistant materials in CO 2 environments for forming adhesive Cr amorphous oxide.With H 2S concentration over about 100ppm to CO 2 concentration,the corrosion becomes H 2S corrosion from the standpoint of the stability of FeCO 3 and FeS corrosion products.The stability of corrosion products of CRAs in H 2S environments relates to the formation behavior of Cr oxide and sulfides such as FeS,Ni 3S 2 and MoS 2.
出处
《石油与天然气化工》
CAS
CSCD
北大核心
2005年第1期43-52,共10页
Chemical engineering of oil & gas
