Pretreatment For Resisting Concrete Corrosion By Microorganism

Concrete constructions play very important roles in modern architecture Engineerings .The corrosion resistance of concrete is one of important indexs that can reflect durability of the concretes, which is related to their operating lives. Among the factors of concrete corrosion, microbiologic corrosion is more universal, excluding inorganic and organic acid or alkali in the wastewater ,salt as well.For example,the sulfide in the water which are discharged by paper mill have strong corrosion to concrete pipes. In this article,the main task is treating the sulfide in the wastewater before it flows into the concrete pipes and the reasons of this microbiologic corrosion are also interp-reted.Under the condition of oxygen,some strain of microorganism is inoculated in a up-flow packed tower reactor in which the sulfide is converted into sulfur or sulfate. In order to disclose the interdependences of many factors that affects the microbiologic process , a large of tests have been carried out. The results illuminate that the sulfide removal rate and the sulfur production rate can arrive at 100% and 73% respectively when the sulfide volume loading rate , dissolved oxygen and the sulfide influent concentration are optimal. Accordingly, three model equations have been founded by regression analysis, which made the right results preview and the optimal election of process parameters into practice.Using above conclusions, the sulfide can be removed effectively ,which would prevent the corrosion of concrete and make them more durable.