污水管道中微生物对混凝土的侵蚀

Microbial-induced Concrete Erosion in Sewage Pipes

微生物侵蚀是影响混凝土污水管道长期性能的重要原因。以污水管道中微生物侵蚀为对象,综述了混凝土表面的初始缓冲与微生物的定植、硫化氢的产生与聚集机理、氧化过程与混凝土的破坏耐久性损伤过程;同时对混凝土中生物硫酸的侵蚀与化学硫酸(硫酸盐)的侵蚀进行了对比;分析了影响微生物侵蚀混凝土的因素及预防措施;对微生物侵蚀混凝土的速率预测模型的优劣进行分析。最后对微生物侵蚀混凝土研究进行了展望。

All over the world,microbial-induced concrete corrosion by producing acids(including organic and inorganic acids)is an important reason affecting the long-term performance of concrete sewage pipes.Understanding of the fundamental corrosion process and the causal agents will help us with the research on the durability of sewage pipes.Taking microbial erosion in sewage pipes as the object,this review describes how microorganisms induce the deterioration of concrete,including the initial buffering and colonization of microorganisms on the concrete surface,the production and aggregation mechanism of hydrogen sulfide,the oxidation process and the damage durability of concrete.The factors influencing microbial erosion of concrete were analyzed;including the hydrogen sulfide gas concentration,the rate of biological oxidation of hydrogen sulfide,permeability of concrete,temperature,humidity and the type of microorganism;among them,the concentration of hydrogen sulfide gas is the most important factor affecting the entire process of microbial erosion of concrete.And then,the erosion of biological sulfuric acid in concrete and the erosion of the chemical sulfuric acid that scholars often use to replace biological sulfuric are compared from two aspects:corrosion process as well as influencing factors.Safeguards against concrete biodeterioration are introduced from three aspects:reducing the rate of hydrogen sulfide production,reducing the rate of hydroxide sulfide,concrete modification and surface coating.Finally,the study of microbial erosion concrete is prospected.