西南酸雨地区土壤中铝溶出规律的探讨

本文介绍了实验室动态模拟结果,对西南地区酸性沉降引起的土壤铝淋溶过程予以探讨。通过计算机推算拟合,提出了预测土壤中铝淋溶容量计算法。运用正交实验法,研究了近似于天然的动态过程中影响铝淋溶的主要因素及各因素间的相关性。得到了当降雨pH<6.0时,酸性土或弱酸性土中铝溶量和时间呈指数关系,以及影响铝溶出因素主要是酸雨的pH值、土壤的缓冲能力和环境温度等结论。     

含铝酸性农药废水合成聚合硫酸铝混凝剂

采用农药三唑醇生产过程中产生的含铝酸性废水为原料,合成了聚合硫酸铝(PAS)液体混凝剂,并用于厂区污水站好氧池出水的混凝处理。考察了碱化剂用量、聚合温度、聚合时间等合成条件及PAS加入量、混凝pH等混凝条件对混凝效果的影响,并比较了PAS与商售聚合氯化铝(PAC)的混凝效果。实验结果表明:在n(碱化剂)∶n(硫酸铝)为2.1∶1、聚合温度为80℃、聚合时间为60 min的条件下,所得PAS液体混凝剂产品的w(Al2O3)为7.8%~9.0%,盐基度为45%~60%,pH为3.5~4.0,产量为0.75 t/t(以废水计);在PAS加入量为2.0 m L/L、混凝pH为10.0时,COD和SS的去除率则分别达到14.6%和83.0%;该PAS可替代厂区常规使用的商售PAC,日节约废水处理成本5 922元。     

Environmental and economic benefit of recycling model of packaging waste: a case study on aluminum

Abstract

In order to achieve sustainable utilization of natural resources, save energy and protect environment and ecosystem, it is important for a region or a nation to develop and implement a viable waste recycling model from both theoretical and practical point of view. Some packaging recycling models operated in developed countries are introduced in this article. Aluminium can recovery and recycling is emphasized. Cost effective, economic and environmental benefit of different models are compared and analyzed. The result shows that all recycling models have their characteristics due to the initial purpose of recovery and the situation of the implementing country. However, all the models contribute to the reduction of municipal solid waste disposal and resources conservation.     

铝在红沿河核电厂地区的初期大气腐蚀表征

目的研究铝在辽宁红沿河核电厂地区的初期大气腐蚀行为。方法按GB/T 6464—1997,将制备好的试样在红沿河核电厂进行大气暴露试验,利用XRD,FTIR,SEM分析技术,对试验6个月和10个月的试样进行腐蚀产物观察与分析。结果铝在红沿河大气暴露腐蚀6个月和10个月样品表面均布满了点蚀坑、腐蚀产物及沉积物,腐蚀产物主要为Al2O3,Al OOH以及一些含氯和含硫的铝盐。腐蚀产物都较疏松,上下表面均有龟裂纹,相邻较近的点蚀坑已相互连接。随腐蚀时间延长,点蚀坑变深变大,朝地面点蚀坑深度已达上百微米。结论铝在红沿河核电厂大气环境中腐蚀以点蚀为主要特征,其腐蚀比普通大气环境中的严重,朝地面的腐蚀比朝天面严重,大气中氯离子及SO2参与铝的腐蚀过程并起促进作用。     

Acidification at Plastic Lake,Ontario: Has 20 Years Made a Difference?

In response to reduced sulphur emissions, there has been a large decrease in sulphate (; −0.97 μeq l⁻¹ year⁻¹) and hydrogen (−1.18 μeq l⁻¹ year⁻¹) ion concentration in bulk precipitation between 1980 and 2000 at Plastic Lake in central Ontario. The benefit of this large reduction in deposition on stream water chemistry was assessed using the gauged outflow from a conifer-forested catchment (PC1; 23.3 ha), which is influenced by a small wetland located immediately upstream of the outflow. Sulphate concentrations declined, but not significantly due to large inter-annual variation in concentration. Between 1980 and 2000, there were significant increases in dissolved organic carbon, ammonium and potassium concentration likely reflecting increased mineralisation in the wetland. Calcium concentrations in PC1 decreased during the two decade period (−2.24 μeq l⁻¹ year⁻¹), as a consequence there was no improvement in stream pH and the Ca:Al ratio in PC1 continued to decline. A similar response was noted in an upland-draining sub-catchment of PC1-08 that has been monitored since 1987. Despite large reductions in deposition and almost complete retention of nitrogen in soil, there has been no improvement (in terms of pH) in stream water at PC1 due to a combination of soil acidification and climatic (droughts, increased mineralisation) perturbations.     

餐饮废水的化学处理方法研究

以聚硅酸铝为混凝剂,用化学法絮凝处理餐饮废水。考查了酸度、混凝剂加入量、搅拌速度、搅拌时间、沉降时间对CODCr去除率的影响。结果表明酸度在pH9～11范围内,每100mL污水中聚硅酸铝加入量为02mL,搅拌速度为45r/min,搅拌15s,沉降15min后,测上清液的化学耗氧量,CODCr去除率可达88%左右。该方法效果好、工艺简单、易于操作管理,有实际应用价值。     

An optimised sequential extraction scheme for the evaluation of vanadium mobility in soils

Reviewing the current state of knowledge about sequential extraction applied for soil vanadium(V) fractionation, we identified an urgent requirement of an sequential extraction(SE) specified for V. Namely, almost all previous SE extracted only 8.4%–48% of total V in soils(excluding residue). Thus, we proposed an eight-step SE for V fractionation in soils according to the knowledge gained from literature and our own dissolution experiments with model minerals. After extracting the mobilisable and adsorbed V with de-ionised water and 5 mmol/L phosphate, 1 mol/L pyrophosphate was applied to gather organic matter bound V which minimised the artefact dissolving Al and Fe(hydr)oxides occurred when using HNO_3–H_2O_2for extraction. Extraction with 0.4 mol/L NH_2OH·HCl was highly selective toward manganese oxides. Fractionation of different crystalline Al and Fe(hydr)oxides associated V with 1 mol/L HCl, 0.2 mol/L oxalate buffer and 4 mol/L HCl at 95°C especially improved the extractability of V incorporated with crystalline phase associated V. The suitability of our new SE scheme was confirmed by its higher selectivity against the target phases and higher extraction efficiencies(55%–77% of total V) with model minerals and 6 soils of different properties than previous SE.     

严酷环境下飞机典型结构异种材料电偶腐蚀特点与防护对策

介绍了电偶腐蚀的原理,以飞机结构上容易出现的三种电偶腐蚀(碳纤维增强环氧复合材料-铝合金、钛合金-铝合金、铝合金-不锈钢)为例,对目前关于这三种电偶腐蚀的研究进行了综述,分析了电偶腐蚀的环境影响因素,综述了耦合材料的失效特点和形式,探讨了利用阻隔、涂层和缓蚀剂等手段减缓和防止电偶的防护措施,指出利用微区测试技术、联合多种研究手段和复合环境因素在研究电偶腐蚀方面的重要性。在多因素条件下,设计模拟耦合件的试验,有利于模拟实际工况的特征。     

AS/PDM复合混凝剂对冬季太湖原水除藻效果研究

由聚二甲基二烯丙基氯化铵(PDM)与硫酸铝(AS)制成的系列稳定AS/PDM复合混凝剂,用于冬季太湖原水的除藻效果研究.通过混凝除藻实验,考察了复合混凝剂加药量、AS与PDM复配质量比(20∶1～5∶1)、PDM特征黏度(0.55～3.99 dL/g)对除藻效果的影响,分析了使用复合混凝剂替代预加氯工艺的可行性.结果表明,对原水使用AS、AS/PDM(0.55/20∶1～3.99/5∶1)复合混凝剂后的余浊达到2 NTU的水厂沉淀出水浊度标准时,其加药量(以Al₂Ｏ₃计)分别为4.24 mg/L、 3.96～1.87 mg/L,除藻率分别为83.00%、 87.52%～90.93%;加药量为4.24 mg/L时,其除藻率分别为83.00%、 88.29%～97.66%,余浊分别为2.00 NTU、 1.76～0.43 NTU.对加氯水的加药量为4.50 mg/L时,AS/PDM(1.53/10∶1)复合混凝剂对原水的处理效果优于AS对加氯水的处理效果;AS/PDM(3.99/5∶1)复合混凝剂对原水的处理效果优于AS、AS/PDM(0.55/20∶1)、AS/PDM(1.53/10∶1)复合混凝剂对加氯水的处理效果.因此,AS/PDM复合混凝剂可明显提高AS对冬季太湖原水的处理效果,与单独使用AS相比,余浊达标时节省加药量,加药量相等时提高处理效果.此外,使用复合混凝剂还可替代预氯氧化工艺中加氯对混凝除藻作用的部分功能,有利于提高水质安全性.     

水中铝元素和钒元素测定方法的研究

应用电感耦合等离子体发射光谱法（ICP—AES法）和紫外一可见分光光度法检测水中的铝元素和钒元素的含量,并对比这两种检测方法的效果。