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Corrosive microorganisms mainly refer to bacteria in nature participating in recycling of sulfur and iron factors, including aerobic bacteria and anaerobic bacteria. The former belong to thiobacillus, such as sulfur oxide bacillus, ferrous oxide bacillus, and thiobacillus thioparus of microbiological corrosion mechanism under microscope. Scattered in acid mine water, soil and marine sludge containing sulfur, they, through oxidized elemental sulfur and reductive sulfide, generate sulfuric acid finally, which corrodes metal and concrete structures. Iron bacteria can oxidize ferrous iron into oxide iron, which sediments on sheath of bacteria or surrounding slime layer, thus forming fulvous knots on metal surface. It is difficult for oxygen to enter knots, so oxygen concentration cell corrosion takes place. Ordinary dangerous bacteria include Gallionellaceae, Leptothrix, Crenothrix and Siderocapsa. In addition, metal corrosion can also be caused by bacteria generating mucus (such as bacteria in pseudomonassp), fungus and some algae and protozoon. Anaerobic bacteria mainly refer to sulfate reducing bacteria, which are widely distributed in pH6~9 soil, fresh water, seawater, and sludge. Vibrio desulphuricans mostly happen in metal corrosion. It reduces sulfate in nature into sulfide. Microbiological corrosion often brings about serious damages to industrial facilities such as underground pipelines, marine cables, and industrial flood system, and further leads to economic loss.

Generally speaking, microbiological corrosion is avoided through the adoption of measures such as organic protection layer (coal tar pitch, epoxy paint, and plastic film), or inorganic protection layer (zinc plating, chromium and cement) and cathode protection (including sacrificial anode or external power method) resisting bacterial damage in soil and water media. In sealed systems (such as metal oil and gas tanks, plane oil tank, and industrial circulation cooling device), corrosion is controlled through eliminating or restraining the multiplication of corrosive microorganisms by oxidized or non-oxidized bacteriacide.