CaO_{2} 缓释氧材料去除地下水氨氮的效能研究

为解决因农田及地表水氨氮污染造成的地下水氨氮质量浓度超标问题,文章通过构建室内柱试验,探究缓释氧材料的性能及其在去除地下水氨氮污染中的适用性。结果表明:将$\mathrm{CaO}_{2}$、水泥、沙、膨润土、$\mathrm{KH_{2}PO_{4}}$按质量比为3.0:3.8:1.8:3.0:1.2制成小球直径为4.0 cm的缓释氧材料,其释氧性能最优,出水溶解氧质量浓度能够持续保持高于8.5 mg/L,pH值稳定在8.50左右;在修复氨氮污染的试验中,集中装填缓释氧材料的修复效果明显优于分散装填,集中装填试验柱在第8天出水氨氮质量浓度满足地下水Ⅲ类水水质标准,去除率达94.1%,且试验周期内未出现亚硝酸盐累积超标问题,表明了该系统修复地下水氨氮污染的可行性与有效性。

In order to solve the problem of excessive ammonia nitrogen concentration in groundwater caused by ammonia nitrogen pollution in farmland and surface water, the performance of slow-release oxygen compounds and their applicability in removing ammonia nitrogen pollution in groundwater were explored by constructing indoor column tests. The results show that the oxygen release performance of the slow-release oxygen compound with a small ball diameter of 4.0 cm prepared with the mass ratio of $ CaO_{2} $, cement, sand, bentonite and $ KH_{2}PO_{4} $ of 3.0 : 3.8 : 1.8 : 3.0 : 1.2 is the best, and the dissolved oxygen concentration and pH value of the effluent are stable at about 8.5 mg/L and 8.50, respectively. The repair effect of concentrated loading slow-release oxygen compound is significantly better than that of dispersed loading. On the 8th day, the concentration of ammonia nitrogen in the effluent of the concentrated loading test column met the water quality standard for Class III groundwater, with a removal rate of 94.1%. And there was no nitrite accumulation exceeding the standard during the test period, indicating the feasibility and effectiveness of the system in repairing groundwater ammonia nitrogen pollution.