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Judging the corrosion degree of sewage pools can be comprehensively assessed by combining superficial characteristics and professional testing indicators. The industrial field is usually divided into four levels. The specific judgment method is as follows: 1. First, do a preliminary screening of appearance, and look at three types of core features to preliminarily judge the corrosion progress with the naked eye.: slight corrosion: There are no obvious cracks on the concrete surface, only slight pulverization, no corrosion on the steel bars, and no leakage in the pool body, which does not affect normal operation. Moderate corrosion: Spider-like cracks appeared in the concrete, white crystals precipitated at the joints, and some parts softened and fell off. The steel bars began to show slight corrosion, and there were occasional small-scale leaks. Severe corrosion: A large area of concrete cracked and peeled off, the exposed steel bars were severely corroded (the cross-section loss exceeded 10%), the pool wall was deformed, there was obvious leakage, and the water quality was abnormal. Extremely severe corrosion: The pool structure is at risk of collapse, the steel bars are corroded and the cross-section loss exceeds 30%, and there is widespread leakage, making it impossible to operate safely. 2. Professional testing for accurate grading. Focus on these indicators. If you need to clarify the anti-corrosion level or do certification, you can make quantitative judgments through the following tests.: 1. Structural and corrosion parameters detection test items judgment standard detection method Concrete pH value A pH value below 9 indicates the occurrence of acid corrosion, and a pH value below 6 indicates severe corrosion. On-site electrode direct detection, or sampling laboratory analysis Steel bar corrosion rate The corrosion rate is less than 5% for mild, 5%-20% for moderate, and greater than 20% for severe ultrasonic testing. Half-cell potential method, drilling sampling, concrete strength/protective layer thickness strength dropped by more than 20% of the design value, and the protective layer was completely carbonized, indicating severe corrosion. Rebound instrument and ultrasonic thickness gauge detected harmful gas concentration and hydrogen sulfide concentration exceeded 100 ppm, indicating active microbial corrosion. Portable gas detector on-site detection 2. Third-party professional certification and grading are for industrial sewage pools. Professional grade certification can be done in accordance with ISO12944 anti-corrosion standards and combined with sewage characteristics.: First, a third-party organization collects on-site corrosion medium (pH, chemical composition, microorganism) parameters ； The laboratory conducts accelerated corrosion simulation tests to test the corrosion rate of coatings or concrete. ； After comprehensive assessment, the anti-corrosion levels will be divided and a certification report will be issued. 3. Key warning signals require special attention. If any of the following situations occurs, it means that corrosion has entered an accelerated stage. Perforation and leakage of the pool may occur within an average of 147 days, and immediate treatment is required.: Obvious network cracks appeared on the surface of the concrete, white crystals precipitated from the joints of the pool wall, and pH fluctuations exceeded ±1.5.