蕉藕淀粉废水絮凝试验

试验采用化学混凝法对蕉藕淀粉加工产生的废水进行处理,研究了硫酸铝,氯化铁,聚合硫酸铁(PSF),聚合氯化铝(PAC),聚丙烯酰胺(PAM)等不同混凝剂种类和投加量对COD、SS和TP去除效果的影响。试验结果表明,聚合氯化铝处理效果最佳,在废水COD、SS和TP的浓度分别为8340mg/L、7060mg/L和320mg/L时聚合氯化铝以500mg/L的用量得到COD、SS和TP的去除率分别为97.1%、98.0%和70%,出水的COD为241mg/L,SS为142mg/L,TP为112mg/L。     

铊,铊中毒及铊在生态系中迁移径迹

铊属于分散元素,独立矿物稀少,极难形成独立铊矿床。铊世界年产量约15吨,几乎都是从有色金属选冶产品中作为副产品顺便回收。我国铊资源比较丰富,按相同等级资源相比,我国铊储量居世界首位。铊的地球化学性质受其电子构型和地质地球化学作用制约,铊原子处于基态时的电子构型为6S26P1。铊有两个地球化学价态,正一价和正三价,在自然界多数呈正一价。铊具有低温成矿,亲硫和高温分散,亲石的双重地球化学性质。铊是有用元素,也是有毒元素。铊被广泛用于超导、电子、合金、光学、化工、玻璃和医药等工业。铊的毒性对哺乳动物比汞、隔、铅、铜、锌还强。铊对生物有毒害,高含量的铊对人体可导致不同程度的铊病,甚至死亡。由于铊矿床的开发利用,使采挖出的含铊岩矿石和冶炼矿渣堆积地表,在长期风化淋滤作用下,使释放的铊进入地表水体、土壤、植物、动物和人体生态链,故引起铊环境污染和铊中毒。     

东营市城市生活垃圾污染防治规划

随着经济的发展和生产生活的需要,城市生活垃圾产量急剧增加,生活垃圾污染防治规划变得日趋重要。通过对东营市城市生活垃圾的现状分析,运用人口、人均日垃圾量双因素法和BP法对生活垃圾产量及成分进行预测,在此基础上进行合理地规划。试图为探讨适合中小城市发展的城市生活垃圾污染防治规划模型研究的进一步开展提供有益的参考。     

Bio-reduction of nitrate from groundwater using a hydrogen-based membrane biofilm reactor

A hydrogen-based membrane biofilm reactor(MBfR) using H2 as electron donor was investigated to remove nitrate from groundwater.When nitrate was first introduced to the MBfR,denitrification took place on the shell side of the membranes immediately,and the effluent concentration of nitrate continuously decreased with 100% removal rate on day 45 under the influent nitrate concentration of 5 mg NO3--N/L,which described the acclimating and enriching process of autohydrogenotrophic denitrification bacteria.A series of short-term experiments were applied to investigate the effects of hydrogen pressures and nitrate loadings on denitrification.The results showed that nitrate reduction rate improved as H2 pressure increasing,and over 97% of total nitrogen removal rate was achieved when the nitrate loading increased from 0.17 to 0.34 g NO3--N/(m2 ·day) without nitrite accumulation.The maximum denitrification rate was 384 g N/(m3 ·day).Partial sulfate reduction,which occurred in parallel to nitrate reduction,was inhibited by denitrififcation due to the competition for H2 .This research showed that MBfR is effective for removing nitrate from the contaminated groundwater.     

Electrochemical degradation of p-nitrophenol with different processes

The electrochemical degradation of p-nitrophenol (PNP) under di erent conditions was investigated. The electrochemical behavior of PNP and its reduction product p-aminophenol (PAP) on stainless steel cathode and Ti/Pt anode through cyclic voltammetry were observed. Electrochemical degradation process was performed in an undivided cell and 92% PNP was removed corresponding to a 22% total organic carbon removal. A divided cell was also used and it was found that PNP degradation was mainly attributed to cathodic reduction, while anodic oxidation was responsible for PNP removal due to the reaction with hydroxyl radicals and surface oxide generated on the anode. The sequential electrolytic processes, reduction-oxidation and oxidation-reduction, were compared in the divided cell. In the case of reduction-oxidation process, the total organic carbon removal reached 40%, but PNP removal was the same with the undivided cell. A black deposit was found in the e uent and identified by Fourier transform infrared spectroscopy as a polymer of PAP produced by the 1,4-addition reaction of quinoneimine. Intermediates left in the solution such as hydroquinone, p-benzoquinone and PAP were determined by high performance liquid chromatography. Whereas, the oxidation-reduction process proved unsatisfying.     

中国村镇突发性水污染事件特征及产生根源分析

鉴于中国村镇突发性水污染事件研究的重要性和必要性,本文通过对中国近五年来发生并被报道的64件村镇突发性水污染事件的统计分析,剖析了中国村镇突发性水污染事件发生的地点、诱因、主要污染物、污染类型、危害以及应急措施等状况,以揭示其发生的规律;在此基础上,本文又深入研究了中国村镇突发性水污染事件发生的根源,指出中国村镇污染源复杂多样、村镇工业布局不合理和管理不到位、农业生产用水需求增加以及村镇饮水工程抵御自然灾害能力弱是造成村镇突发性水污染的风险。     

Fe3+、Ce3+掺杂TiO2光催化降解气相二苯并呋喃

以气相二苯并呋喃为研究对象,考察了在TiO2、Ce3+/TiO2和Fe3+/TiO2 3种不同光催化剂作用下,反应物初始浓度、湿度、气体循环速率和光强等因素对间歇式光催化反应速率的影响,并建立了估算和测定二苯并呋喃光催化反应常数和Langmuir吸附常数的数学模型和方法.结果表明,Fe3+和Ce3+掺杂修饰TiO2光催化剂后,提高了对二苯并呋喃的光催化降解活性,其中Fe3+/TiO2光催化活性最高;随着二苯并呋喃初始浓度的增大,其光催化降解速率也随之增大;适量的水蒸气存在可以促进二苯并呋喃的降解,但当水蒸气过量后,反而阻碍二苯并呋喃光催化降解;随着气体循环速率加快和光强的增大,二苯并呋喃光催化降解初始速率也随之增大;TiO2、Ce3+/TiO2和Fe3+/TiO2光催化降解二苯并呋喃反应速率常数k分别为34.54×10-5、36.23×10-5和37.95×10-4mg.(min.m2)-1.     

Effect of biosurfactant[0] on the sorption of phenanthrene onto original and H2O2-treated soils

The objective of this study was to examine the effect of biosurfactant on sorption of phenanthrene (PHE) onto the original or H2O2-treated black loamy soil (typic isohumisols) and red sandy soil (typic ferralisols). The sorption isotherms were performed with the original and "soft" carbon-removed soils in the presence and absence of biosurfactant (200 mg/L). The sorption and degradation of biosurfactant were investigated. The result showed that organic matter played an important role in PHE sorption onto the black loamy and red sandy soils, and the PHE sorption isotherms on the "soft" carbon-removed soils exhibited more nonlinearity than those on the original soils. The values of partition coefficient (Kd) on the original black loamy soil with or without 200 mg/L biosurfactant were 181.6 and 494.5 mL/g, respectively. Correspondingly, in the red sandy soil, Kd was 246.4 and 212.8 mL/g in the presence or absence of biosurfactant, respectively. The changes of Kd suggested that biosurfactant inhibited PHE sorption onto the black loamy soil, but facilitated PHE sorption onto the red sandy soil. The nonlinearity of PHE sorption isotherm was decreased in the presence of biosurfactant. Site specific sorption might occur during PHE sorption onto both the original and the "soft" carbon-removed soils in the presence of biosurfactant. It was noted that biosurfactant could also be sorbed onto soils. The maximal sorption capacity of the red sandy soil for biosurfactant was (76.9 ± 0.007) μg/g, which was 1.31 times that of black loamy soil. Biosurfactant was degraded quickly in the two selected soils, and 92% of biosurfactant were mineralized throughout the incubation experiment for 7 d. It implied that biosurfactant should be added frequently when the remediation of polycyclic aromatic hydrocarbon (PAH)-contaminated soils was conducted through PAH desorption approach facilitated by biosurfactant.     

东海西湖凹陷区溢油行为数值模拟

研究东中国海中日共同开发区附近海域溢油污染的问题,在模拟水动力场的基础上模拟了海上溢油漂移扩散情况。在表层流场和风场的作用下漂移,而油膜的扩展则通过油粒子的随机走动来实现。本文以东海西湖凹陷原油为溢油油种,通过模拟分析不同季节和不同风况下的溢油事故,对溢油油膜的扫海范围进行了分析。     

工业园区固体废物生命周期管理边界模型的构建

工业园区内企业众多,副产品和固体废物排放量犬,生产过程也复杂,采用生命周期对固体废物进行管理显得也复杂很多。该文从构建工业园区固体废物生命周期管理边界模型出发,并以电子信息产业园区为例,试着将固体废物与不同的企业或生产过程紧密耦合,构建可行的较稳定的生命周期管理边界模型。