To save freshwater, people want to replace freshwater with seawater for cooling in industry. However, in seawater cooling system, the corrosion of the outlet of heat-exchanger and its following steel components is ver...To save freshwater, people want to replace freshwater with seawater for cooling in industry. However, in seawater cooling system, the corrosion of the outlet of heat-exchanger and its following steel components is very serious. Application of Al sacrificial anode is one effective method to prevent steel equipment in seawater from corrosion, but at 50℃, Al anodes in common use are not applicable. So it is important to study the relevant rules governing Al anode performance at high temperature. Since the working potential is an important factor affecting the performance of Al anode, we try to find the rules governing how additional elements affect the working potential at various temperature. Twenty-eight kinds of Al sacrificial anode were made for the experiment by the method of the Chinese National Standard GB4948—85. The interrelation of additional elements in the Al anode and the working potential of anode were studied by the method of grey box analysis. The results showed that the influencing order of elements on the working potential was the same on the whole; and that In, Zn, Mg and Ga were good additional elements for aluminum sacrificial anode in order to get negative working potential.展开更多
硫作为海洋生物地球化学循环中的重要元素,在本学术领域内备受重视。研究表明,硫的化合物是许多海域海水、沉积物、间隙水中重金属、氧化还原环境等的控制性因素(宋金明,1990,1991,1992a,1992b,1993;Andreae,1990; Fossing et al.,1992;...硫作为海洋生物地球化学循环中的重要元素,在本学术领域内备受重视。研究表明,硫的化合物是许多海域海水、沉积物、间隙水中重金属、氧化还原环境等的控制性因素(宋金明,1990,1991,1992a,1992b,1993;Andreae,1990; Fossing et al.,1992;Kiene,1992;Lerman,1979)。黄河口附近海域是我国著名的渔场,特别是近年来近海发现了油气田,使此区域成为近海河口区研究的典型场所,因而该海域的建港和油气田开发前期的评价等急需与之相关项目的调查研究。近年来,我所的研究人员对渤海的辽东湾、南黄海、冲绳海槽以及东海等海区硫的体系做了较为系统的调查研究(宋金明,展开更多
The effect of sulfate reducing bacteria (SRB) on electrochemical corrosion behavior of 16Mn steel, and galvanic corrosion behavior of the steels in the juncture area between bacterial and bacteria free sea mud was stu...The effect of sulfate reducing bacteria (SRB) on electrochemical corrosion behavior of 16Mn steel, and galvanic corrosion behavior of the steels in the juncture area between bacterial and bacteria free sea mud was studied in laboratory under simulated conditions. Sea mud dense with SRB was taken from the Qingdao beach. Part of the sea mud was sterilized and the rest was kept in the original condition. The sterilized and original sea mud was put respectively into two plastic testing troughs electrically connected by an agar potassium chloride salt bridge. Galvanic and non galvanic 16Mn steel samples were put into the trough at the same intervals. The SRB number measured by the MPN tri tube method was about 2.4×10 5 per 100 g mud and was kept basically the same during the experimental period. The ρ, pH, eH, T, S (salinity) were measured simultaneously. The galvanic current was measured with zero resistance galvanometer and the corrosion rate was measured with the weight loss method.The results showed that (1) the corrosion rate of 16Mn steel in bacterial sea mud was 4.0 times that in bacteria free sea mud; (2) galvanic corrosion occurs between steel samples buried in different (bacterial and bacteria free) sea mud. The steel sample in the bacterial sea mud was the anode of a galvanic couple and had higher corrosion rate than that of the non galvanic sample. The existence of the galvanic couple increased the corrosion rate of the sample in bacterial sea mud by 4.1%.展开更多
Corrosion behavior of steel in the juncture area of sea clay and sand was studied. The results show that galvanic corrosion occurred between steel samples buried in sea clay and sand, and that the polarity of the galv...Corrosion behavior of steel in the juncture area of sea clay and sand was studied. The results show that galvanic corrosion occurred between steel samples buried in sea clay and sand, and that the polarity of the galvanic cell reversed after some testing later. The cause of reversing of polarity is discussed.展开更多
The effect of trace elements Bi and Ti on the electrochemical property of aluminium sacrificial anode in seawater was studied . Different amounts of Bi and Ti were alloyed with Al-Zn-In to make 9 types of aluminium sa...The effect of trace elements Bi and Ti on the electrochemical property of aluminium sacrificial anode in seawater was studied . Different amounts of Bi and Ti were alloyed with Al-Zn-In to make 9 types of aluminium sacrificial anodes . Anode closed circuit potential, discharge capacities and current efficiencies were measured in the laboratory . The results show that the effect of Bi is greater than that of Ti.展开更多
文摘To save freshwater, people want to replace freshwater with seawater for cooling in industry. However, in seawater cooling system, the corrosion of the outlet of heat-exchanger and its following steel components is very serious. Application of Al sacrificial anode is one effective method to prevent steel equipment in seawater from corrosion, but at 50℃, Al anodes in common use are not applicable. So it is important to study the relevant rules governing Al anode performance at high temperature. Since the working potential is an important factor affecting the performance of Al anode, we try to find the rules governing how additional elements affect the working potential at various temperature. Twenty-eight kinds of Al sacrificial anode were made for the experiment by the method of the Chinese National Standard GB4948—85. The interrelation of additional elements in the Al anode and the working potential of anode were studied by the method of grey box analysis. The results showed that the influencing order of elements on the working potential was the same on the whole; and that In, Zn, Mg and Ga were good additional elements for aluminum sacrificial anode in order to get negative working potential.
文摘硫作为海洋生物地球化学循环中的重要元素,在本学术领域内备受重视。研究表明,硫的化合物是许多海域海水、沉积物、间隙水中重金属、氧化还原环境等的控制性因素(宋金明,1990,1991,1992a,1992b,1993;Andreae,1990; Fossing et al.,1992;Kiene,1992;Lerman,1979)。黄河口附近海域是我国著名的渔场,特别是近年来近海发现了油气田,使此区域成为近海河口区研究的典型场所,因而该海域的建港和油气田开发前期的评价等急需与之相关项目的调查研究。近年来,我所的研究人员对渤海的辽东湾、南黄海、冲绳海槽以及东海等海区硫的体系做了较为系统的调查研究(宋金明,
基金supported by the"Ninth-Five Plan"Great Project of the Chinese Academy of Sciences(KZ951-A1-405-04).
文摘The effect of sulfate reducing bacteria (SRB) on electrochemical corrosion behavior of 16Mn steel, and galvanic corrosion behavior of the steels in the juncture area between bacterial and bacteria free sea mud was studied in laboratory under simulated conditions. Sea mud dense with SRB was taken from the Qingdao beach. Part of the sea mud was sterilized and the rest was kept in the original condition. The sterilized and original sea mud was put respectively into two plastic testing troughs electrically connected by an agar potassium chloride salt bridge. Galvanic and non galvanic 16Mn steel samples were put into the trough at the same intervals. The SRB number measured by the MPN tri tube method was about 2.4×10 5 per 100 g mud and was kept basically the same during the experimental period. The ρ, pH, eH, T, S (salinity) were measured simultaneously. The galvanic current was measured with zero resistance galvanometer and the corrosion rate was measured with the weight loss method.The results showed that (1) the corrosion rate of 16Mn steel in bacterial sea mud was 4.0 times that in bacteria free sea mud; (2) galvanic corrosion occurs between steel samples buried in different (bacterial and bacteria free) sea mud. The steel sample in the bacterial sea mud was the anode of a galvanic couple and had higher corrosion rate than that of the non galvanic sample. The existence of the galvanic couple increased the corrosion rate of the sample in bacterial sea mud by 4.1%.
基金This work was supported by Corrosion Science LaboratoryInstitute of Corrosion and Protection of Mctals, Academia Sinica
文摘Corrosion behavior of steel in the juncture area of sea clay and sand was studied. The results show that galvanic corrosion occurred between steel samples buried in sea clay and sand, and that the polarity of the galvanic cell reversed after some testing later. The cause of reversing of polarity is discussed.
文摘The effect of trace elements Bi and Ti on the electrochemical property of aluminium sacrificial anode in seawater was studied . Different amounts of Bi and Ti were alloyed with Al-Zn-In to make 9 types of aluminium sacrificial anodes . Anode closed circuit potential, discharge capacities and current efficiencies were measured in the laboratory . The results show that the effect of Bi is greater than that of Ti.
