壳聚糖的物理/化学改性及其对含酚废水的处理

将壳聚糖物理改性为球形颗粒,然后在微波辐射下,球形壳聚糖与柠檬醛接枝反应,再与NaBH4还原反应,制备一种新型环保材料--物化改性壳聚糖.采用红外光谱仪(IR)、X衍射仪(XRD)、电子显微镜(SEM)和比表面测定及孔径分析仪(BET)结构表征改性壳聚糖.通过含酚制药废水的动态小柱吸附实验,研究了时间、柱高和出水流速等...     

人工湿地基质的筛选及其对猪场废水厌氧消化液中氨氮吸附性能研究

采用静态吸附实验,对比了岷江砂、沱江砂、青衣江砂、沸石、活性炭对猪场废水厌氧消化液中氨氮的吸附去除效率,基于氨氮去除能力、购买成本与运费的比较,筛选出性价比较高的基质--岷江砂作为四川地区人工湿地的基质处理猪场废水厌氧消化液.吸附实验表明,砂对氨氮的去除率随振荡时间和投加量的增加而增加.通过吸附等温曲线Langmuir...     

复合型CoO/TiO2光催化剂降解亚甲基蓝动力学研究

以钛酸四丁酯为前驱体,采用溶胶凝胶法,制备了CoO掺杂的TiO2光催化剂。利用X射线衍射（XRD）、扫描电镜（SEM）、透射电镜（TEM）、紫外可见漫反射（UV-vis DRS）对催化剂进行了分析、表征。以中压汞灯为光源,研究了亚甲基蓝（MB）在CoO/TiO₂微粒水悬浮液中的降解动力学。结果表明：所制备的催化剂活性组分主要是锐钛矿型的二氧化钛和CoO固溶体,粒径为25～30 nm,分布均匀。亚甲基蓝的光催化降解动力学满足一级动力学,在一定的浓度范围内,反应速率常数随初始浓度增大而减少,适当的掺钴量可以有效地提高TiO₂光催化活性,其最佳掺杂量重量百分比为0.25%。     

某退役后辐照装置的辐射水平监测与评价

依据国家相关标准对某退役后辐照装置周围的辐射水平进行监测与评价,通过数据评价得出该单位辐照装置退役场所未受到放射性污染,其退役后对环境的辐射影响可以忽略。     

Municipal solid waste source-separated collection in China: A comparative analysis

A pilot program focusing on municipal solid waste (MSW) source-separated collection was launched in eight major cities throughout China in 2000. Detailed investigations were carried out and a comprehensive system was constructed to evaluate the effects of the eight-year implementation in those cities. This paper provides an overview of different methods of collection, transportation, and treatment of MSW in the eight cities; as well as making a comparative analysis of MSW source-separated collection in China. Information about the quantity and composition of MSW shows that the characteristics of MSW are similar, which are low calorific value, high moisture content and high proportion of organisms. Differences which exist among the eight cities in municipal solid waste management (MSWM) are presented in this paper. Only Beijing and Shanghai demonstrated a relatively effective result in the implementation of MSW source-separated collection. While the six remaining cities result in poor performance. Considering the current status of MSWM, source-separated collection should be a key priority. Thus, a wider range of cities should participate in this program instead of merely the eight pilot cities. It is evident that an integrated MSWM system is urgently needed. Kitchen waste and recyclables are encouraged to be separated at the source. Stakeholders involved play an important role in MSWM, thus their responsibilities should be clearly identified. Improvement in legislation, coordination mechanisms and public education are problematic issues that need to be addressed.     

Polychlorinated naphthalenes (PCNs) in riverine and marine sediments of the Laizhou Bay area, North China

PCN congeners were analyzed in marine and riverine sediments of the Laizhou Bay area, North China. Concentrations of PCNs ranged from 0.12 to 5.1 ng g⁻¹ dry weight (dw) with a mean value of 1.1 ng g⁻¹ dw. The levels of PCNs varied largely, with industrial group approximately ten folds higher than those of the rural in riverine sediment. A strong impact by direct discharge from local factories was suggested. Similar compositional profiles were found within groups. High resemblance of compositional profiles between industrial samples and Halowax 1014 was observed. It was indicated that PCNs in riverine sediments were mainly from release of industrial usage, with additional contributions from industrial thermal process at certain sites. In marine sediments, it was suggested that PCNs along the coast of Laizhou Bay were mainly controlled by riverine input. While in the central bay, PCN distributions were possibly impacted by combined multiple factors.     

Combined inverse modeling approach and load duration curve method for variable nitrogen total maximum daily load development in an agricultural watershed

Purpose  

Nonpoint sources (NPS) pollution has been an important cause for water quality impairment worldwide. To take the temporal variations of both NPS pollution and in-stream attenuation into consideration, an inverse modeling approach and the load duration curve (LDC) method were combined for variable nutrient total maximum daily load (TMDL) development.     

干湿交替中碳酸化对废物水泥窑共处置产品中重金属浸出的影响

通过比较连续浸出、碳酸化保存间歇浸出和密封保存间歇浸出3种浸出条件下,废物水泥窑共处置产品--混凝土中Cr、Ni、As、Cd和Pb的浸出量,研究了干湿交替的环境中碳酸化对混凝土中重金属浸出的影响.结果表明,不同的漫出条件对混凝土中重金属的浸出产生了一定的影响.间歇浸出过程降低了重金属在混凝土固相与孔隙水(液相)中的浓度...     

西北黄土地区现场石油污染土壤生物修复研究

通过在陕北安塞油田某废弃油井建立中试试验基地,以实验室中筛选分离得到的高效降解石油的优势菌为添加的高效菌,研究土壤石油初始浓度、营养物质和高效菌对石油降解的影响.结果表明:(1)在各土壤石油初始浓度下,石油降解率总体均随降解时间的延长而升高.在土壤石油初始质量浓度为15.34 g/kg下,72 d时石油降解率为47.8...     

固定床中粒状脱硫剂除尘效率的研究

建立了非稳态过滤下的固定床颗粒层除尘效率模型.该模型尽可能地包含了影响固定床颗粒层除尘的参数,反映了沉积粉尘对除尘效率的影响;研究了以粒状脱硫剂为滤料的固定床在不同颗粒层厚度、空床气速、粒径下的除尘效率.结果表明,在颗粒层厚度为400～800 cm、空床气速≤0.4 m/s的条件下,颗粒层的除尘效率可达90％以上.