基于GIS的点源污染扩散模拟可视化研究

环境是人类赖以生存和发展的基本条件,环境污染问题已经成为威胁人类生存的头号问题之一.大气环境污染直接危及到人类的生命和健康,对自然环境造成严重影响.本文以某工厂烟窗点源有害污染气体SO2和NO2排放为例,获取了污染物实地扩散浓度观测值,基于GIS技术和大气点源扩散高斯模型,研究SO2和NO2在特定大气条件下的扩散规律,实现了有害气体扩散的可视化表达,为自然环境影响评价探索新途径和新方法.     

聚硅铝系列絮凝剂的制备表征及其应用

制备了聚硅铝系列絮凝剂 ,利用透射电镜 (TEM)和准弹性激光散射 (PCS)进行了粒径分布和结构表征 ,发现聚硅铝系絮凝剂具有与硫酸铝和聚合氯化铝不同的结构形态 ,聚硅硫酸铝 (PASS)聚集体之间的距离与颗粒直径成线性关系。通过对原水的混凝处理对比 ,发现聚硅铝絮凝剂在降低浊度、去除有机物和某些元素方面具有显著优势。其中PASM和PASFⅢ对重金属和放射性元素的去除效果最好 ,尤其是经PASFⅢ处理后水中残留铝的去除率为 1 5 .3 % ,解决了使用铝盐增高铝含量的难题。经济分析也表明聚硅铝系絮凝剂价格低廉 ,具有良好的应用前景     

Preparation of a novel iron-based biochar composite for removal of hexavalent chromium in water

The chitosan-stabilized ferrous sulfide nanoparticles were loaded on biochar to prepare a composite material FeS-CS-BC for effective removal of hexavalent chromium in water. BC and FeS-CS-BC were characterized by Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) analyses. Batch experiments were employed to evaluate the Cr(VI) removal performance. The experimental results showed that the removal rate of Cr(VI) by FeS-CS-BC(FeS:CS:BC?=?2:2:1) reached 98.34%, which was significantly higher than that of BC (44.58%) and FeS (79.91%). In the pH range of 2–10, the removal of Cr(VI) by FeS-CS-BC was almost independent of pH. The limitation of coexisting anions (Cl^?、SO₄^2?、NO₃^?) on Cr(VI) removal was not too obvious. The removal of Cr(VI) by FeS-CS-BC was fitted with the pseudo-second-order dynamics, which was a hybrid chemical-adsorption reaction. The X-ray photoelectron spectroscopy (XPS) analysis result showed that Cr(VI) was reduced, and the reduced Cr(VI) was fixed on the surface of the material in the form of Cr(VI)–Fe(III).

Removal of hexavalent chromium from wastewater by FeS-CS-BC composite synthesized by impregnation.

     

燃煤过程中微量元素砷和硒形态转化的热力学平衡模拟

砷和硒是煤中的易挥发有毒微量元素。由于砷和硒在燃煤烟气中的浓度极低以及实验条件的限制 ,目前化学热力学平衡分析已成为预报烟气中砷和硒等有毒元素形态分布的主要理论分析方法。本文综述了热力学平衡分析方法应用于砷和硒在燃煤过程中形态转化和平衡分布等方面的研究进展。首先用于热力学平衡分析的是只含有砷或硒一种微量元素和煤中主量元素及氯元素的简单体系 ,并假设烟气中只有理想气体组成的气相和纯凝聚相的理想模型。然而是否考虑砷和硒与其他微量、主量或次量元素的相互作用 ,砷和硒所有可能存在的反应 ,以及在熔融相砷和硒与熔融物的结合会严重地影响模型的预报结果 ,因此 ,目前热力学平衡体系已发展成为含有包括砷和硒在内的多个微量元素和煤中所有主量、次量元素 ,以及包括熔融相在内的非理想多相复杂体系     

螺旋状中空纤维膜吸收器脱硫性能的研究

用自组装的膜吸收器试验研究了不同操作条件下的烟气脱硫特性。实验结果表明，脱硫过程传质阻力主要集中在气相和膜上，利用螺旋管技术可以强化气相的传质。     

天然气引射调峰系统的噪声形成及其治理研究

采用天然气引射调峰技术，能使上海某储配站10台天然气高压球罐的储气调峰能率提高68％，大大有助于解决天然气用气高峰时的供需平衡问题，并能节约初投资人民币1亿元。但使用超音速引射器后，当球罐压力下降到某一值时会产生高频噪声，影响管束区操作环境。本文分析了噪声产生的原因．提出了合理的噪声治理方案，并进行了方案的实施。实践证明：噪声治理效果良好，降低了管束区噪声污染，达到了国家“工业企业噪声卫生标准”。     

垃圾填埋场渗滤液生物处理技术改造实例分析

综述了垃圾填埋场渗滤液的物理化学、生物、土地处理等技术。对某地已投入使用的垃圾填埋场渗滤液的生物处理设施技术改造进行了较详细的分析探讨。     

Evolution and kinetics of volatile organic compounds generated during low-temperature polymer degradation

A method using direct flame ionization detector (FID) measurement was developed to study total volatile organic compound (VOC) emissions during thermal degradation of polymers. This method was used to estimate organic emissions from different polymers, such as low-density polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and commingled postconsumer streams, such as recycled carpet residue and auto shredder residue (ASR). The effects of process parameters, such as temperature, heating rate, and residence time, were also studied. Significant VOC emissions were observed at normal processing temperatures, particularly from recycled polymers. Each polymer showed a distinct evolution pattern during its thermal degradation. The kinetics of VOC emissions were also studied using a nonisothermal technique. The kinetic parameters were in agreement with data from the literature.     

Cr6+和Cr3+对水花生几种生理生化指标的影响比较

通过Cr6 和Cr3 对水花生 (Alternantheraphiloxeroides)的叶及根的某些生理生化指标影响的对比研究发现 ,Cr6 和Cr3 均能对水花生产生毒害 ;铬污染后 ,水花生的叶绿素含量、超氧化物歧化酶 (SOD)、过氧化物酶 (POD)、过氧化氢酶 (CAT)活性和可溶性蛋白含量 5项重要生理生化指标发生相应变化 ;Cr6 的毒性明显大于Cr3 ,根的受害程度比叶严重。     

采用生物发光检测法进行Ames试验的研究

将自行构建的含有青海弧菌荧光酶基因的质粒pACYCL184引入Ames试验的4个菌株TA97、TA98、TA100、TA102中,构建成能够生物发光的工程菌,分别命名为TAL97、TAL98、TAL100、TAL102.实验表明,该4株工程菌保持原出发菌株所具有的与Ames试验相关的性状,对各类致突变剂有良好的反应,且可用平皿计数法进行致突变试验.其发光值与致突变剂浓度存在良好的量效关系,故可用发光检测取代原Ames试验的平皿计数,使检测更简单、方便、快速.图3表3参11