离子色谱法测定水中氯离子的不确定度评定

分析了用离子色谱法测试洁净水中氯离子的过程中不确定度和系统误差的来源,对各不确定度分量进行了评定及合成,并计算得出合成不确定度和扩展不确定度。结果表明,体积不确定度分量对整个试验的不确定度影响较小,质量不确定度分量相对影响较大。     

Comparisons of the film peeling from the composite oxides of quartz sand filters using ozone, hydrogen peroxide and chlorine dioxide

To solve the problem of shortened backwashing intervals in groundwater plants, several disinfectants including ozone (O₃), hydrogen peroxide (H₂O₂) and chlorine dioxide (ClO₂) were examined to peel off the film from the quartz sand surface in four pilot-scale columns. An optimized oxidant dosage and oxidation time were determined by batch tests. Subsequently, the optimized conditions were tested in the four pilot-scale columns. The results demonstrated that the backwashing intervals increased from 35.17 to 54.33 (H₂O₂) and to 53.67 hr (ClO₂) after the oxidation treatments, and the increase of backwashing interval after treatment by O₃ was much less than for the other two treatments. Interestingly, the treatment efficiency of filters was not affected by O₃ or H₂O₂ oxidation; but after oxidation by ClO₂, the treatment efficiency was deteriorated, especially the ammonia removal (from 96.96% to 24.95%). The filter sands before and after the oxidation were characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. Compared with the oxidation by O₃ and H₂O₂, the structures on the surface of filter sands were seriously damaged after oxidation by ClO₂. The chemical states of manganese on the surfaces of those treated sands were only changed by ClO₂. The damage of the structures and the change of the chemical states of manganese might have a negative effect on the ammonia removal. In summary, H₂O₂ is a suitable agent for film peeling.     

An experimental and thermodynamic equilibrium investigation of the Pb, Zn, Cr, Cu, Mn and Ni partitioning during sewage sludge incineration

The effects of different chlorides and operational conditions on the distribution and speciation of six heavy metals (Pb, Zn, Cr, Cu, Mn and Ni) during sludge incineration were investigated using a simulated laboratory tubular-furnace reactor. A thermodynamic equilibrium investigation using the FactSage software was performed to compare the experimental results. The results indicate that the volatility of the target metals was enhanced as the chlorine concentration increased. Inorganic-Cl influenced the volatilization of heavy metals in the order of Pb > Zn > Cr > Cu > Mn > Ni. However, the effects of organic-Cl on the volatility of Mn, Pb and Cu were greater than the effects on Zn, Cr and Ni. With increasing combustion temperature, the presence of organic-Cl (PVC) and inorganic-Cl (NaCl) improved the transfer of Pb and Zn from bottom ash to fly ash or fuse gas. However, the presence of chloride had no obvious influence on Mn, Cu and Ni. Increased retention time could increase the volatilization rate of heavy metals; however, this effect was insignificant. During the incineration process, Pb readily formed PbSiO₄ and remained in the bottom ash. Different Pb compounds, primarily the volatile PbCl₂, were found in the gas phase after the addition of NaCl; the dominant Pb compounds in the gas phase after the addition of PVC were PbCl₂, Pb(ClO₄)₂ and PbCl₂O₄.     

Gasification and smelting system using oxygen blowing for plastic waste including polyvinyl chloride

A new type of waste gasification and smelting system using oxygen blowing based on high-temperature metallurgy, was developed by Sumitomo Metals, Japan. This system can steadily gasify and melt not only municipal waste, but also plastic waste and polyvinyl chloride (PVC) waste by using a top-blow oxygen lance together with sideways-blow oxygen lances. As a result of gasification in the high-temperature reducing atmosphere and rapid gas cooling, dioxin-free, high-calorie purified gas was produced. Ash components in the wastes were smelted in a high-temperature reducing atmosphere, and high-quality slag free of heavy metals was produced. Most of the chlorine in the wastes was converted into hydrogen chloride in the off gas. The hydrogen chloride can be recovered as hydrochloric acid or chlorine, which are recyclable to PVC manufacturing.     

液氯瞬时泄放扩散过程实时仿真

分析液氯钢瓶或容器爆炸后的氯气扩散各阶段的数学模型，设计了计算机实时仿真软件，最后给出大气扩散模型计算的云团在风力驱使下漂浮途中造成污染区域的等浓度曲线。文章的结论和实施方案对其它液化气体、尤其是重气的扩散过程模拟及实时仿真有参考价值。     

Formation of organic chloride in the treatment of textile dyeing sludge by Fenton system

In the oxidation treatment of textile dyeing sludge, the quantitative and transformation laws of organic chlorine are not clear enough. Thus, this study mainly evaluated the treatment of textile dyeing sludge by Fenton and Fenton-like system from the aspects of the influence of Cl⁻, the removal of polycyclic aromatic hydrocarbons (PAHs) and organic carbon, and the removal and formation mechanism of organic chlorine. The results showed that the organic halogen in sludge was mainly hydrophobic organic chlorine, and the content of adsorbable organic chlorine (AOCl) was 0.30 mg/g (dry sludge). In the Fenton system with pH=3, 500 mg/L Cl⁻, 30 mmol/L Fe²⁺ and 30 mmol/L H₂O₂, the removal of phenanthrene was promoted by chlorine radicals (•Cl), and the AOCl in sludge solid phase increased to 0.55 mg/g (dry sludge) at 30 min. According to spectral analysis, it was found that •Cl could chlorinate aromatic and aliphatic compounds (excluding PAHs) in solid phase at the same time, and eventually led to the accumulation of aromatic chlorides in solid phase. Strengthening the oxidation ability of Fenton system increased the formation of organic chlorines in liquid and solid phases. In weak acidity, the oxidation and desorption of superoxide anion promoted the removal and migration of PAHs and organic carbon in solid phase, and reduced the formation of total organic chlorine. The Fenton-like system dominated by non-hydroxyl radical could realize the mineralization of PAHs, organic carbon and organic chlorines instead of migration. This paper builds a basis for the selection of sludge conditioning methods.     

用二氧化氯降解废水中的苯胺类化合物（1）COD去除规律的研究

用二氧化氯氧化降解８种苯胺类化合物，测定了ＣＯＤ去除率与时间及ＣＯＤ去除率与ＣｌＯ２用量之间的关系；结果表明最终的ＣＯＤ去除率多数都在７０％以上，羟基类苯胺化合物可达９０％以上．反应符合ｌｎＣＯＤ＝Ｋ１ＷＣｌＯ２＋Ａ１及ｌｎＣＯＤｔ＝Ｋ２ｔ＋Ａ关系式．ＣＯＤ去除率还与ｐＨ值的大小有一定的相关性．     

新型消毒剂二氧化氯的开发与应用

从保护饮用水的安全与卫生出发，介绍了替代液氯和其它氯制品的新型消毒剂——二氧化氯所具有的优点，特别是可有效抑制三卤代烷（ＴＨＭＳ）的产生；讨论了二氧化氯的最佳投放方式及ＣｌＯ－２和ＣｌＯ－３等有害副产物生成的机理和控制方法     

二氧化氯的稳定性研究

分别讨论了在一定条件下，通常意义的二氧化氯水溶液与稳定的二氧化氯水溶液的降解速率，同时，研究了ｐＨ值对二氧化氯水溶液稳定性的影响．     

FIELD-LABORATORY DETERMINED AVOIDANCES OF THE SPOTFIN SHINER AND THE BLUNTNOSE MINNOW TO CHLORINATED DISCHARGES1

ABSTRACT: The responses of the spotfin shiner (Notropis spilopterus) and bluntnose minnow (Pimephales notatus) to intermittent chlorine discharges from a fossil fuel power plant in the New River were investigated by seine collections in the chlorinated discharge channel, and chlorine avoidances were obtained in a field laboratory at the power plant in Glen Lyn, Virginia. No fish were captured by seine during chlorination periods when the total chlorine (TCR) and free chlorine (FCR) residuals were, respectively, 0.46 and 0.27 mg/1 or higher at river water temperatures of 12 C or less. For collections made between eight-hour chlorination periods, the number of fish was reduced by approximately 50% at 0.20 and 0.06 mg/1 TCR and FCR, respectively. Significant (0.05 level) laboratory avoidances occurred at 0.10 to 0.20 mg/1 TCR (0.03 to 0.14 mg/1 FCR) for both species when exposed to increasing TCR concentrations of 0.10, 0.20, 0.30 and 0.40 mg/1. Responses varied with acclimation temperature (6, 12, 18 and 24 C) with no consisteent trends between species. When exposed to a constant TCR concentration during any one test (0.14, 0.18 and 0.26 mg/1 for the spotfin shiner, and 0.11 and 0.17 mg/1 for the bluntnose minnow), significant avoidances were observed at 0.26 and 0.17 mg/1 for each species, respectively. In all laboratory trials, occurrence or residence times decreased with increasing chlorine concentration, with residence times as high as 64.7% at 0.10 mg/1 TCR and as low as 8.3% at 0.40 mg/1 being observed.