Fenton氧化-序批式膜生物反应器耦合处理干法腈纶废水

采用Fenton氧化-序批式膜生物反应器(SBMBR)组合工艺处理干法腈纶废水。结果表明,在废水初始pH值为3.0,H2O2投加量为90.0 mmol/L,Fe2+投加量为20.0 mmol/L,反应时间为2.0 h的条件下,Fenton氧化预处理对腈纶生产废水的COD去除率达到47.0%以上,COD由1 091 mg/L降至560 mg/L,废水的BOD5/COD由0.32升至0.69,废水的可生化性得到显著提高。Fenton处理出水与丙烯腈废水等比例混合后,采用SBMBR进行生化处理,在水力停留时间为24 h,90 min缺氧/150 min好氧交替运行的条件下,COD、NH4+-N和TN的平均去除率分别为71.7%、97.2%和47.4%,碳源不足是限制TN去除效果的主要影响因素。在无外加碳源的条件下,组合工艺处理后出水COD和NH4+-N浓度分别为117 mg/L和1.7 mg/L,出水水质可以稳定达到国家一级排放标准(GB8978-1996)。     

利用废弃物衍生燃料的热化学处理法制富含氢气合成气

为了探讨利用热化学方式从城市垃圾中制取富含氢气合成气过程的要素影响,解析氢气发生特性及其与主要影响要素之间的关系。在分析了城市生活垃圾组分特性的基础上,将其加工成组分均一的废弃物衍生燃料(refuse de-rived fuel,RDF),并在700、800和900℃等3个温度条件下,分别开展了RDF的热解、气化及水蒸汽气化等实验。研究表明,RDF的加工不但可有效降低垃圾含水率,还可将垃圾热值提高近1倍。温度和添加水蒸汽是从RDF中制取富含氢气合成气过程中的关键影响要素。其中,温度对氢气生成起到至关重要的决定作用,温度的提高对促进H2浓度的提高有利,同时,在气化过程中添加水蒸汽,可有效促进CO和H2等有价气体组分生成。在900℃的高温水蒸汽气化处理过程中,可获得H2浓度最高为34.13%的合成气。另外,800℃热解过程所产生的合成气热值最高,达到14 509 kJ/Nm3。     

响应面法优化聚丙烯酸/腐殖酸/累托石吸附剂的制备条件

以累托石、丙烯酸及腐殖酸为原料制备出能同时吸附重金属和多环芳烃的吸附剂聚丙烯酸/腐殖酸/累托石,采用响应面试验设计法优化吸附剂的制备条件。利用Design Expert软件,建立了预测吸附剂对Cd2+、菲吸附量的二次回归模型,对回归模型进行了方差分析,并确定了吸附剂的最佳制备条件。结果表明,二次回归模型能较好地模拟Cd2+、菲的吸附量与影响因子丙烯酸中和度、引发剂量和交联剂量之间的关系。各因子对Cd2+吸附量的影响次序为:交联剂量>引发剂量>丙烯酸中和度;对菲吸附量的影响次序为引发剂量>交联剂量>丙烯酸中和度。吸附剂的最佳制备条件为:累托石、丙烯酸和腐殖酸三者的质量比为65∶30∶5,丙烯酸中和度、引发剂量和交联剂量分别为75.16%、2.57%和0.44%。在此优化条件下制备的吸附剂对Cd2+和菲的吸附量分别为170.19 mg/g和7.36 mg/g。     

连片生态浮床对微污染河水的净化效果

选取漕桥河的支流庙尖浜作为实验河段,以睡莲(Nymphaea alba)、菖蒲(Acorus calamus Linn)和水芹(Oenan-the javanica(Blume)DC)作为微污染水体净化的浮床植物,研究连片生态浮床的净化能力随季节的变化和浮床面积对连片生态浮床净化能力的影响。结果显示,秋-冬-春季节内植物的净化能力随季节变化呈"U"型,相应的河水水质的变化呈一个倒置的"U"型;在一定营养负荷和植物正常生长状况下,沿水流方向,氮、磷含量随浮床面积的增加而降低——春季时,随浮床面积增加,菖蒲区对TN的去除率由8.6%增加到26.7%,TP的去除率由17.1%增加到58.2%,水芹区对TN和TP的去除率最高可达22.0%和28.0%。研究表明连片生态浮床是河道水质改善的有效可行的方法之一,可为太湖入湖河流的营养物质控制提供科学依据。     

铁屑粉煤灰组合处理含磷废水

实验研究了铁屑粉煤灰组合处理含磷废水的除磷效果.通过单因素实验,考查了铁屑粉煤灰质量比、反应时间、pH值和投加量对除磷效果的影响.实验结果表明,该法除磷的最优条件为铁屑和粉煤灰的质量比为2∶1,反应时间为20 min,pH值为6,投加量为20 g/L.在最优实验条件下磷的去除率达到了97.5％.对比了该法和粉煤灰吸附法与传统铁屑法的除磷效果.与单一粉煤灰吸附法和传统铁屑法除磷的结果相比较,铁屑粉煤灰组合除磷的方法具有明显优势.     

氧化物催化剂对非热等离子体催化降解甲苯的影响

考察了在干燥气氛下不同氧化物催化剂对非热等离子体催化降解甲苯的影响。从甲苯降解率、碳平衡、CO2选择性和O3去除4个方面,对比了氧化物催化剂的介电性能、表面供氧能力和比表面积与多孔结构对反应产生影响的强弱。结果表明,催化剂的介电性能有利于甲苯降解率、碳平衡和O3产量的提高,但对CO2选择性和O3去除的影响极小;一定能量密度下,催化剂比表面积与多孔结构对CO2选择性和O3去除所产生的影响要强于介电性能;催化剂表面供氧能力可明显促进反应的进行,其对反应所产生的影响要强于比表面积与多孔结构。     

稠油污水回用锅炉处理工艺的应用

新疆油田公司稠油污水处理普遍采用成熟的离子调整旋流反应水处理技术,污水处理后达到回用锅炉水质标准SY/T 0097-2000《稠油油田采出水用于蒸汽发生器给水处理设计规范》,供给油田专用高压注汽锅炉用水。采用相同技术建成的采油一厂稠油处理站污水回用锅炉处理工艺投用后,处理后污水回用锅炉,减少了含油污水的外排,充分利用了稠油污水的热能,取得了良好的经济和社会效益。     

充分利用环保倒逼机制促进产业结构调整升级

淄博市污染聚集,环境质量易受外来因素影响,产业结构不合理,污染物排放量大,排放强度高。但其充分发挥环保的倒逼作用,通过建立健全环保政策法规体系,严格执行高于省及国家标准的地方环保标准,大力发展高新技术和现代服务业,加快改造传统产业,极大地促进了产业结构升级和经济发展方式的转变。     

Toxicological effect of MPA-CdSe QDs exposure on zebrafish embryo and larvae

Cadmium selenium (CdSe) quantum dots (QDs) are semiconductor nanocrystals that hold wide range of applications and substantial production volumes. Due to unique composition and nanoscale properties, their potential toxicity to aquatic organisms has increasingly gained a great amount of interest. However, the impact of CdSe QDs exposure on zebrafish embryo and larvae remains almost unknown. Therefore, the lab study was performed to determine the developmental and behavioral toxicities to zebrafish under continuous exposure to low level CdSe QDs (0.05-31.25 mg L⁻¹) coated with mercaptopropionic acid (MPA). The results showed MPA-CdSe exposure from embryo to larvae stage affected overall fitness. Our findings for the first time revealed that: (1) The 120 h LC₅₀ of MPA-CdSe for zebrafish was 1.98 mg L⁻¹; (2) embryos exposed to MPA-CdSe resulted in malformations incidence and lower hatch rate; (3) abnormal vascular of FLI-1 transgenic zebrafish larvae appeared after exposure to MPA-CdSe including vascular junction, bifurcation, crossing and particle appearance; (4) larvae behavior assessment showed during MPA-CdSe exposure a rapid transition from light-to-dark elicited a similar, brief burst and a higher basal swimming rate; (5) MPA-CdSe induced embryos cell apoptosis in the head and tail region. Results of the observations provide a basic understanding of MPA-CdSe toxicity to aquatic organisms and suggest the need for additional research to identify the toxicological mechanism.     

Ozonation as an advanced oxidant in treatment of bamboo industry wastewater

The present study employed ozonation process to treat the bamboo industry wastewater (BIWW). The impact of ozone dosage and initial organic concentration on color, COD and TOC removal rates were studied along with characterization of the major organics in raw and treated wastewater. The results suggested the ozone dosage of 3.15 g h⁻¹ (concentration 52.5 mg L⁻¹) was suitable for the treatment. After 25 min ozonation of 1 L raw wastewater, the color, COD and TOC removal efficiencies were 95%, 56% and 40%, respectively, with an influent COD concentration of 835 mg L⁻¹. The ratio of kg O₃ kg⁻¹ COD at 3.15 g h⁻¹ was 2.8 (<3), revealing that ozonation was a cost effective process for tertiary treatment of BIWW. Longer oxidization time was required to achieve similar results for raw wastewater with higher COD concentration. The chromatogram from gel permeation chromatography revealed that ozonation resulted in the breakdown of high molecular weight compounds into lower molecular weight components but could not completely mineralize the organic matter. The majority of these compounds were identified in both raw and ozonated samples via GC-MS analysis. In addition to ester derivatives as the main intermediates of ozonation, 1-chloroctadecane, methyl stearate, benzophenone and α-cyperone were identified as the by-products of ozonation.