Removal Efficiency And Influence Factor Of Iron Series PRB For The Treatment Of Groundwater Pollution

For the past few years, The antibiotics was being abused more serious than before. Due to the unreasonable discharge of antibiotics effluent and offscum, a mass of antibiotics passed into the groundwater through different methods. Nowadays, in above all over the world, antibiotics were detected more or less in the groundwater. Because of its relatively stable nature and ecotoxicity. Antibiotics has became an environment pollutants with the public’ concern. However, there is still few researches about the disposition of antibiotics pollution in groundwater. How to solve the groundwater which polluted by antibiotics has catch the reseacher’s attention.In all over the groundwater remediation technologies. The permeable reactive barrier(PRB) has a mass of advantages, such as the low-cost、no need for external power、high efficiency、small interference to nature environment、good cost performance.et. All these made the PRB became one of the most popular in-situ groundwater remediation technologies.In this research, we made a series of bench experiments first, then we built a medium-scale PRB with zero-valent iron(ZVI) and monitored its decomposition efficiency and influence factor of the groundwater which polluted by tetracycline first. The effection of external electric field and aeration was investigated. The reactive medium filled in this device was collected after the experiment and analyzed. With all these methods, we made an preliminary exploration of the reaction mechanism. After that, we built a bench-scale PRBr with iron oxide and monitored its decomposition efficiency too. The effection of external conditions was investigated.The ZVI-PRB had a good performance in the decomposition of tetracycline. when the solution’s concentration is 50mg/L,60% of the tetracycline in the solution was removed by this device which had operated 320 hours. At the beginning of the reaction, the reductive degradation of ZVI is the main reaction existed in PRB. In the later-period of, flocculation became the main reaction. The study indicated that the external electric field can optimized the quality of effluent at the beginning of the reaction, but cannot affect the reaction mechanism. Aeration could aggrandize the device’s removal efficiency in the later petiod.The iron-oxide PRB had an good performance in tetracycline’ decomposition too. 62.31% and 46.56% of the tetracycline in the solution which concentration is 50mg/L was removed by the two kinds of iron-oxide PRB after operating 72 hours. The ferroferric oxide performed better than iron trioxide. Acid environment can improve the efficiency of iron-oxide PRB at the beginning of the reaction. Iron strength can optimized the decomposition efficiency in a center degree.