粉煤灰合成分子筛及处理含氟废水的研究

实验利用工业废渣——循环流化床粉煤灰合成出较高结晶度的X型和P型分子筛,合成过程无须高温焙烧预处理.通过XRD分析表征,发现该法合成分子筛结晶度较高,X型和P型分子筛相对结晶度分别达68%～75%和55%.实验应用合成分子筛进行载铁改性,并对NaF模拟的工业含氟废水进行了除氟实验.结果表明,载铁X型分子筛处理工业含氟废水效果良好,除氟率可达74%～98%,除氟容量达25.0～30.0 mg/g.在处理含氟废水过程中,载铁合成分子筛与其他除氟剂相比较,具有除氟率高、除氟容量大、反应迅速的特点.     

水体富营养化综合水质模型及其应用研究

针对水体富营养化问题，探讨了一种多参数水体富营养化的水质生态模型（ＷＡＳＰ４）。在阐述其原理和计算方法的基础上结合汉江武汉段１９９２年性水华事件的实例进行水质模型，其特点是，不仅能够较好地模拟浮游植物的变化过程。而且能够提供发生水华问题的原因和生态机理的解释。     

土地利用规划环境影响评价——以双流县为例

土地利用规划对社会经济的发展和生态环境都会产生深刻的影响，尽早开展其环境影响评价对于保证决策的正确性是十分必要的。文章介绍了土地利用规划环境影响评价的基本程序和内容，提出了一系列的评价原则，分析了与其他环境影响评价的关系。并以双流县为例进行了分析。     

Nitrate removal from aqueous solutions by magnetic cationic hydrogel: Effect of electrostatic adsorption and mechanism

Excessive nitrate(NO_3~-) is among the most problematic surface water and groundwater pollutants.In this study,a type of magnetic cationic hydrogel(MCH) is employed for NO_3~-adsorption and well characterized herein.Its adsorption capacity is considerably pHdependent and achieves the optimal adsorption(maximum NO_3~--adsorption capacity is95.88±1.24 mg/g) when the pH level is 5.2-8.8.The fitting result using the homogeneous surface diffusion model indicates that the surface/film diffusion controls the adsorption rate,and NO_3~-approaches the center of MCH particles within 30 min.The diffusion coefficient(D_s) and external mass transfer coefficient(k_F) in the liquid phase are1.15 × 10~(-6) cm~2/min and 4.5 × 10~(-6) cm/min,respectively.The MCH is employed to treat surface water that contains 10 mg/L of NO_3~-,and it is found that the optimal magnetic separation time is 1.6 min.The high-efficiency mass transfer and magnetic separation of MCH during the adsorption-regeneration process favors its application in surface water treatment.Furthermore,the study of the mechanism involved reveals that both-N~+(CH_3)_3 groups and NO_3~-are convoluted in adsorption via electrostatic interactions.It is further found that ion exchange between NO_3~-and chlorine occurs.     

基于多源观测资料的海峡西岸城市春季颗粒物污染研究

以海西区沿海城市为研究对象,重点分析了厦门地区2017年春季大气颗粒物污染过程中边界层要素演变及颗粒物水平和垂直分布特征,并利用地面观测数据、气溶胶激光雷达、卫星遥感分析等多源观测资料,探讨了3月1—2日颗粒物污染过程.研究表明,海西区颗粒物污染过程中,暖区条件下静稳小风和高温高湿条件有利于局地细颗粒物的吸湿增长,细颗粒物占比较高,而在受冷锋南下影响下东北大风和高湿条件下,粗颗粒占比较高;海西区沿海各城市的细颗粒污染趋势基本一致,而粗颗粒污染峰值在沿海城市由北向南依次出现,表现出显著的向南传输的特征;海西区细颗粒污染主要集中在近地面层,受人为源排放累积影响,粗颗粒则是由外源输入,并沉降至近地面附近;冷空气南下过程中,在由锋前暖区的静稳条件向冷锋过境转变时,气溶胶污染由局地累积向区域传输转变,颗粒物尺度也从细颗粒物转变为粗颗粒物.海西区空气总体较为清洁,在污染相对较小条件下,颗粒物污染是通过多来源、多尺度的污染物造成的,是受细颗粒局地源产生和输送及外源粗颗粒物的输入和沉降共同影响的.     

2,4,4'-三溴联苯醚的光降解研究

以固相微萃取(SPME)结合气相色谱(GC)、气相色谱-质谱联用(GC/MS)技术作为分析检测手段,研究光源、有机溶剂、无机盐与腐殖酸对BDE-28光降解的影响,实验结果表明,光源是影响其降解的主要因素,其次,丙酮、铜离子和腐殖酸对其降解的影响较显著.光源对BDE-28光降解速率的影响为300 W汞灯500 W金卤灯100 W汞灯500 W氙灯;有机溶剂对BDE-28降解速率的影响为甲醇/水(1∶1)甲醇己烷甲苯乙腈丙酮;无机离子的影响各有差别:K+、Na+、SO2-4、NO-3、Cl-对BDE-28降解影响不明显,而Fe3+、NH+4促进BDE-28的降解,Fe2+、Cu2+、Br-抑制BDE-28的降解;腐殖酸抑制BDE-28的降解.     

Influence of changes in hydrodynamic conditions on cadmium transport in tidal river network of the Pearl River Delta, China

With rapid economic development, the Pearl River Delta (PRD) of China has experienced a series of serious heavy metal pollution events. Considering complex hydrodynamic and pollutants transport process, one-dimensional hydrodynamic model and heavy metal transport model were developed for tidal river network of the PRD. Then, several pollution emergency scenarios were designed by combining with the upper inflow, water quality and the lower tide level boundary conditions. Using this set of models, the temporal and spatial change process of cadmium (Cd) concentration was simulated. The influence of change in hydrodynamic conditions on Cd transport in tidal river network was assessed, and its transport laws were summarized. The result showed the following: Flow changes in the tidal river network were influenced remarkably by tidal backwater action, which further influenced the transport process of heavy metals; Cd concentrations in most sections while encountering high tide were far greater than those while encountering middle or low tides; and increased inflows from upper reaches could intensify water pollution in the West River (while encountering high tide) or the North River (while encountering middle or low tides).     

Nitrogen mass flow in China's animal production system and environmental implications

China's economic boom in recent decades has stimulated consumer demand for animal products and consequently, a vast expansion in animal production. From 1978 to 2006, the number of animals increased by 322% for pigs, 209% for poultry, and 2770% for dairy cattle. The objective of the present study was to quantify nitrogen mass flow in China's animal production system at the national scale and to elucidate potential environmental implications. A comprehensive analysis was performed combining statistical records with data from the scientific literature and supplemental survey information. Results indicate that approximately 18 Mt of N flowed through the Chinese animal production system in 2006. Nitrogen input to the system was from various feed materials, including 6.8 Mt (38% of total) from roughage, 4.4 Mt (24%) from byproducts, 2.3 Mt (13%) from cereal grains, and 1.6 Mt (9%) each from crop residues and oilseed cakes, with the remaining N (16%) obtained from other feedstuffs. Nitrogen outputs from the system included edible animal products (2.4 t, 13% of total), nonedible animal parts (e.g., bones, skins) (3.8 Mt, 21%), and excreta (12 Mt, 66%). At the national level, the excreta would average 28 Mg (as excreted) and 90 kg N ha(-1) of cropland. However, at the provincial level, it varied from 1 Mg ha(-1) (5 kg N ha(-1)) in Qinghai to 97 Mg ha(-1) (243 kg N ha(-1)) in Sichuan. In regions with excreta in the intermediate rate (e.g., Hebei Province, 115 kg N ha(-1)) or high rare (e.g., Sichuan Province, 243 kg N ha(-1)), animal manure contributes significantly to nutrients polluting groundwater and/or surface waters. It is crucial for China to develop and implement proper management practices to maximum the beneficial use of the 12 Mt excreta N while minimizing its environmental footprint.     

含氰化物废水生物处理研究进展

综述了含氰化物废水的主要处理技术和存在的问题,探讨了微生物降解氰化物的生物化学途径以及生物降解机理.介绍了影响氰化物生物降解性能的因素和含氰化物废水的生物处理特点,综述了含氰化物废水生物处理的最新研究进展,并展望了微生物降解氰化物技术的发展趋势与应用前景.     

塔河油田集输管线20#钢在CO2/H2S环境中的腐蚀行为

为充分了解20#钢在塔河油田集输管线工况环境中的腐蚀行为,采用高温高压釜研究CO2/H2S分压比、温度和pH值对20#钢在CO2/H2S环境中的腐蚀规律的影响,并利用扫描电镜(SEM)分析腐蚀产物形貌特征。结果表明:CO2分压不变时,随着H2S分压的增加,20#钢的腐蚀速率先增大后减小,H2S分压为0.01 MPa时的腐蚀速率达到最大0.435 mm/a;随着温度的升高,20#钢的腐蚀速率逐渐增大,在100℃时腐蚀速率高达2.280 mm/a;CO2控制下20#钢的腐蚀速率随着pH值的增大而减小;H2S控制下20#钢的腐蚀速率随着pH值的增大而增大。