金属负载型硅藻土水泥基除磷材料在海南富营养化水体中应用研究

The surface water of most cities in China is in the state of eutrophication. In Hainan Province, there are many wetlands in the state of eutrophication and eutrophication, and even some water bodies have lost the function of drinking water sources. Phosphate is the leading factor in the eutrophication of water body, but the powder adsorbent for phoshate removal could not be recycled, and it is easy to cause two pollution. In this study, Hainan Province, high temperature, high humidity and high salinity of the special climatic conditions and environmental characteristics of the rapid growth of algae, is studied in tropical regions of the metal loaded diatomite cement based material removal. This material has the characteristics of high adsorption capacity, simple preparation process, low cost and strong practicability, it is used for ecological restoration of water eutrophication, and has the value of recyclable. The project intends to adopt the macro and micro water chemistry experiment based on spectral methods, research in natural water and other metal ions in the phosphorus load adsorption type diatomite cement based on material removal, microscopic structures that phosphorus and other ions, so as to construct the model fitting and prediction of the adsorption behavior, to guide the practical application the purpose of. At the same time, aiming at the eutrophication degree and treatment requirements of different water bodies in Hainan, the structure and dosage of cement based phosphorus removal materials can be designed to provide a guarantee for restoring wetland eco-environment.

我国大部分城市的地表水已经处于富营养化状态。在海南省已有多个湿地呈现中营养化和富营养化状态，甚至有些水体失去了其饮用水水源的功能。磷是引起水体富营养化的主导因素，但由于磷的粉末吸附剂没有成型性能，无法回收，极易造成二次污染。本研究针对海南省高温、高湿、高盐份的特殊气候条件以及藻类生长迅速的环境特点，研究适用于热带地区的金属负载型硅藻土水泥基除磷材料。此种材料具有吸附容量高、制备工艺简单、价格低廉且实用性强，用于水体富营养化的生态修复，并具有可回收利用的价值。项目拟采用宏观水化学实验与微观谱学手段结合，研究天然水体中的磷与其他离子在金属负载型硅藻土水泥基除磷材料上的微观吸附机理，推断磷与其他离子的微观吸附构型，从而构建模型对其吸附行为进行拟合与预测，达到指导实际应用的目的。同时，针对海南不同水体富营养化程度与处理要求，具体设计水泥基除磷材料的结构形式与投加量，可为恢复湿地生态环境提供保障。

本项目成功合成了用于富营养化水体除磷的负载铁的硫铝酸盐水泥基吸附剂，具有制备简单和易于固液分离等特点，在批量和固定床试验条件下，本研究所制备的无机胶凝吸附材料（Inorganic cementitious adsorbent, ICA）均表现了良好的磷酸盐去除效果。ICA具有低价，制备简单，安全有效和易于分离回收的特点，且易于磷的回收利用，为富营养化水下工程材料提供了新的选择。ICA对磷的吸附容量为44.36-47.69 mg/g，优于许多报道的高价吸附剂。竞争离子的干扰较弱，在水体常见离子共存条件下。磷的吸附量可达最佳值的95％以上。模拟人工湿地试验表面，ICA处理的床体积数为2660~898，优于大多数水泥基除磷材料。且ICA的应用不会造成有毒重金属的二次污染。吸附磷后的ICA可用于替代磷肥使用，以ICA为磷源的空心菜的干重为0.40±0.05〜0.41±0.03g，与非P源样品（0.19g±0.07g）相比有显着增加。在本项目的资助下，项目负责人团队发表论文9篇（其中7篇SCI收录），获批发明与实用新型专利各一项，培养博士生2名，硕士生4名，本科生十余名。