Wang Dong-bo, Li Xiao-ming, Ding Yan, Zeng Tian-jing, Zeng Guang-ming
College of Environmental Science and Engineering, Hunan University, Changsha, PR China.
Recent Pat Food Nutr Agric. 2009 Nov;1(3):236-42. doi: 10.2174/2212798410901030236.
Excessive nitrogen and phosphorus supply to freshwater negatively affects water quality and ecosystem balance through a process known as eutrophication. This can lead to increased wastewater treatment costs, a reduction in the biological diversity and recreational value of natural water bodies. Besides, algal blooms can result in loss of livestock and human health issues. Therefore, efficient and reliable nitrogen and phosphorus removal methods are required. In wastewater containing relatively high concentrations of nitrogen and phosphorus (e.g. wastewater from chemical fertilizer plant, the supernate of dewatered sludge, etc.), these elements are difficult to remove economically to reach the appropriate compliance limits by biological methods. On the other hand, both nitrogen and phosphorus are nutrients for the plants, and recently, nitrogen and phosphorus recovery by precipitation (e.g. struvite) has drawn much attention, because nitrogen and phosphorus precipitates can be utilized as a fertilizer and both phosphorus and ammonium can be simultaneously removed. Thus, this review summarized nitrogen and phosphorus recovery methods, during which nitrogen and phosphorus compounds can be used as a raw material for the fertilizer industry, including the options of struvite and hydroxyapatite formation and other feasible using options. In this article most important patents are also discussed.
向淡水过量供应氮和磷会通过一种称为富营养化的过程对水质和生态系统平衡产生负面影响。这可能导致废水处理成本增加、天然水体的生物多样性和娱乐价值降低。此外，藻华会导致牲畜损失和人类健康问题。因此，需要高效可靠的氮和磷去除方法。在含有相对高浓度氮和磷的废水中（例如化肥厂废水、脱水污泥上清液等），通过生物方法很难经济地去除这些元素以达到适当的合规限值。另一方面，氮和磷都是植物的养分，最近，通过沉淀（如鸟粪石）回收氮和磷受到了广泛关注，因为氮和磷沉淀物可作为肥料利用，并且磷和铵可以同时去除。因此，本综述总结了氮和磷的回收方法，在此过程中氮和磷化合物可作为肥料工业原料，包括鸟粪石和羟基磷灰石形成的选择以及其他可行的利用选择。本文还讨论了最重要的专利。
