It is well known that microbial corrosion has been a major problem in the gas phase of wastewater treatment plants. With the corrosion-resistant guide applied to the repair of deteriorated concrete, the determination of removal depth and choice of removal method are essential to be performed. Based on this approach, three sites were investigated and conclusionsare gotten as follows: 1) The chemical index (penetration depth of sulfuric acid) can exactly show the deterioration depth of concrete;

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... ) The removal methods depend on the chemical index. It is more efficient to take advantage of high-pressure water washing and choose the high pressure of more than or equal to 30 MPa; 3) As the actual removal depth is different from the deterioration depth, it is required to take into account influence such as ability, efficient and cost. The removal depth should be decided by mid-position between the chemical deterioration depth and the physical deterioration depth. On the further work, the effect of remainder sulfur compound on bond strength of repair side should be studied.