改性沸石去除污染水体中磷的实验研究

用沸石做载体,将六水氯化铁负载其上,进行除磷的实验研究。通过正交试验优化了改性工艺,在沸石与FeCl3.6H2O的质量比为8∶2,煅烧温度300℃,煅烧时间4 h时,去除效果最好。探讨了沸石用量、吸附时间、溶液的pH值、溶液初始浓度对改性沸石除磷效果的影响。实验表明:此吸附剂对于模拟含磷废水具有较好的去除性能,当模拟含磷废水的浓度为5 mg/L、时间2 h,用量为10 g/L,pH为7左右,其去除率达到了80%以上。本实验研究对于富营养化水体的治理具有一定的参考价值。     

沸石-活性炭组合工艺处理微污染原水的研究

为改善水质 ,研究了沸石与活性炭 (GAC)组合的新工艺。沸石不仅具有去除水中浊度的作用 ,而且还可去除水中氨氮和部分有机物。沸石与活性炭的吸附性能有互补特点 ,沸石 活性炭组合工艺可有效去除污染物。试验结果表明 ,沸石对CODMn的去除率在 10 %左右 ,对浊度、氨氮、三氯甲烷的去除率分别在 6 0 % ,95 %和 4 0 %以上。沸石 活性炭组合工艺对水中苯酚、阴离子洗涤剂(LAS)和三氯甲烷的去除率分别在 6 0 % ,89% ,99%以上     

沸石吸附水体中氨氮的热力学和动力学过程研究

随着近年来各大自然水体富营养化程度的加重,废水中氨氮的处理显得尤为重要。我国浙江缙云有丰富的沸石矿藏,研究其对于沸石的吸附过程有着明显的应用价值。实验结果显示:在288～318 K范围内的温度对沸石吸附氨氮过程影响较小,在氨氮初始浓度为30 mg/L的条件下,小粒径沸石对氨氮的48 h吸附容量为1.13±0.06 mg/g,去除率为91%。大粒径沸石对氨氮的48 h吸附容量为1.10±0.06 mg/g,去除率为87%。沸石对氨氮的吸附过程遵循二级吸附动力学方程,Freundlich和Langmuir等温吸附方程均适用于描述沸石吸附氨氮的热力学过程。本研究表明天然沸石是一种合适的吸附剂,可用于废水或者天然水体中氨氮的去除。     

沸石用于含铬废水处理初步研究

利用沸石作为吸附剂,通过改变沸石用量、pH值、C_r~(6+)初始浓度、吸附时间等多个因素以确定沸石处理含C_r~(6+)废水的最佳工艺条件,对含C_r~(6+)重金属废水进行吸附处理。结果表明,投加量3.0 g/100 m L,振荡时间60 min,去除效果最佳。相同条件下,使用硫酸亚铁改性后的人造沸石比未改性的天然沸石去除率高出13.64%。利用沸石这种廉价的物质,在提高对含C_r~(6+)废水去除效率的同时也降低了运行成本,达到以废治废的目的。     

暴雨径流氮污染控制复合沸石湿地系统研究

滇池水体富营养化与藻类的大量繁殖 ,造成生物多样性降低 ,经济损失和生态破坏严重。本文根据滇池流域暴雨径流污染物组成特征和土地利用状况 ,在对沸石吸附性能和内部孔隙结构研究的基础上 ,首次构建以沸石为填料 ,停留时间短 ,占地面积小 ,能高效去除溶解性氮的强化复合沸石湿地系统。利用沸石对氨氮的吸附作用和物化、生物作用实现暴雨径流污染控制。室内静态吸附试验研究表明 ,沸石对NH+ 4 具有很强的选择吸附性 ,吸附容量最高者可达到 11 2mg/ g沸石 (6 0目 )。利用电镜扫描、X衍射谱图分析沸石样品 ,结果表明其内部孔穴发达 ,直径多在 5 μm以上 ,是很好的微生物载体。室内动态吸附试验表明 ,沸石本身粒径以及滤速、接触时间等运行参数对沸石对NH+ 4 吸附效果有显著影响 ;沸石对氨氮的吸收过程中存在动态的吸附 解吸平衡过程。通过构建并运行复合沸石湿地系统开展现场中试研究 ,试验运行结果表明该系统对高负荷暴雨径流污染有明显的去除效果。对暴雨水中NH+ 4 可快速稳定去除 ,平均去除率85 %以上 ,去除机理主要是沸石对NH+ 4 的选择吸附作用 ;对NO-3 -N去除效率随着原水中C/N由 1上升至 5 ,去除率由不足 5 %迅速升至 4 0 %以上 ,去除机理以反硝化作用为主 ,碳源是否充足直接制约系统去除NO-3 -N     

壳聚糖基印迹水凝微球对Cr (VI)的选择性吸附研究

目前水环境污染物成分复杂,常用的化学沉淀法已很难将重金属污染物分类去除并资源化利用,由此产生了大范围的危废污染环境,需要进行二次处理。利用离子印迹技术对壳聚糖基水凝微球进行改性,制备具有对Cr (VI)特异识别性能的吸附材料(CTS-IGB）,对其在单一Cr (VI)溶液和模拟电镀废水中的吸附行为特征进行研究。研究结果表明:在20 ℃、pH值为3时,CTS-IGB在单一Cr (VI)溶液和模拟电镀废水中Cr (VI)的吸附量在180 min内分别达到37.4 和44.3 mg/g,半饱和吸附时间仅分别为5.8和23.5 min;吸附行为符合准二级动力学。吸附等温线拟合表明吸附过程符合Freundlich模型;热力学参数表明吸附过程是放热反应,且吸附后无序度减小;相比于未改性壳聚糖水凝微球,CTS-IGB在共存离子（模拟电镀废液及其他双组份溶液）工况下对Cr (VI)的选择性提高32%~74%。该材料可作为潜在的吸附材料用于污染水环境中Cr (VI)的分离及回收。     

基于正交试验的沸石改性去除污水中磷的研究

利用硫酸铝和硫酸镁改性沸石来进行含磷废水的处理,通过正交试验得出最佳的沸石改性条件为:沸石、硫酸铝、硫酸镁=8∶2∶1(质量比),400℃下焙烧4 h,改性后的沸石相对于未改性的沸石对磷的去除效果提高了20%。探讨了改性沸石投加量、吸附时间、pH、初始浓度对除磷率的影响,并对改性沸石进行了正交试验研究,结果表明:改性沸石除磷的最佳条件:吸附时间70 m in、pH为6.5、投加量4 g、初始浓度为1.5 mg/L。     

洗浴废水处理工艺中混凝预处理的作用与效果研究

采用混凝沉淀—过滤—固定化生物活性炭—膜滤—UV 消毒工艺处理洗浴废水,整体试验结果比较理想,在物化处理过程中混凝环节至关重要。为此研究了混凝对浊度、LAS、COD_(Cr)、洗浴浴香的处理效果。研究结果表明：当投药量大于25mg/L 时,混凝沉淀可以把平均浊度为65NTU的原水降低到15NTU 以下,对 LAS、COD_(Cr)的去除率可达62%和50%以上,因此混凝是去除洗浴废水中悬浮物质、LAS 和有机污染物有效的物化处理单元;但是混凝不能有效地去除洗浴废水中的浴香。     

小凌河底泥污染物含量的分布特征及生态风险评价

以锦州市境内小凌河干流河段为例，经采样分析测定其表层底泥样品的总磷、总氮、有机质含量，并按照沉积物质量标准评定3种污染物的污染程度，评价分析Zn、Ni、Cr、Cu的相关性及潜在生态风险。结果表明：总磷、总氮、有机质含量为0.02%～0.06%、0.01%～0.05%、0.50%～1.60%之间，三者的同源性较好，正相关性显著，总体处于安全级，总磷、总氮和有机质含量较低；Zn、Ni、Cr、Cu的正相关性极显著，营养物与重金属之间的相关性不明显，底泥中重金属污染较轻；低潜在生态风险的采样点占比为93.75%，从低到高的潜在生态风险排序为Zn 相似文献   

超重力床+活性炭臭氧+沸石处理炸药废水工程调试

某单位采用超重力床+紫外线臭氧氧化法预处理炸药生产高浓度有机废水,再用活性炭臭氧氧化+沸石吸附法处理炸药生产综合废水。经过调试运行,超重力床单元在温度50℃时,COD的去除率为75%,氨氮去除率为35%,TNT去除率13%;紫外线臭氧氧化单元,COD去除率可达30%,TNT去除率可达40%,但对氨氮无去除效果;活性炭+臭氧氧化单元的COD去除率达到65%,TNT去除率达到30%,但氨氮去除率小于10%;活性炭+沸石吸附单元的COD去除率大于50%,氨氮去除率可达到80%。为了降低沸石的更换频率,在沸石填料中种植了菖蒲和美人蕉等水生植物,利用沸石对氨氮进行富集,再利用植物对氨氮进行吸收利用。废水处理装置经过调试、整改后,运行效果良好,处理出水水质达到《弹药装药行业水污染排放标准》(GB 14470.3-2011)。     

Biological treatment of heavy metals in acid mine drainage using sulfate reducing bioreactors.

The uncontrolled release of acid mine drainage (AMD) from abandoned mines and tailing piles threatens water resources in many sites worldwide. AMD introduces elevated concentrations of sulfate ions and dissolved heavy metals as well as high acidity levels to groundwater and receiving surface water. Anaerobic biological processes relying on the activity of sulfate reducing bacteria are being considered for the treatment of AMD and other heavy metal containing effluents. Biogenic sulfides form insoluble complexes with heavy metals resulting in their precipitation. The objective of this study was to investigate the remediation of AMD in sulfate reducing bioreactors inoculated with anaerobic granular sludge and fed with an influent containing ethanol. Biological treatment of an acidic (pH 4.0) synthetic AMD containing high concentrations of heavy metals (100 mg Cu(2+)l(-1); 10 mg Ni(2+)l(-1), 10 mg Zn(2+)l(-1)) increased the effluent pH level to 7.0-7.2 and resulted in metal removal efficiencies exceeding 99.2%. The highest metal precipitation rates attained for Cu, Ni and Zn averaged 92.5, 14.6 and 15.8 mg metal l(-1) of reactor d(-1). The results of this work demonstrate that an ethanol-fed sulfidogenic reactor was highly effective to remove heavy metal contamination and neutralized the acidity of the synthetic wastewater.     

Pollutant removal efficiency of alternative filtration media in stormwater treatment.

Sorption experiments were used to assess the ability of various materials (sand, compost, packing wood, ash, zeolite, recycled glass and Enviro-media) to remove heavy metal contaminants typically found in stormwater. Compost was found to have the best physicochemical properties for sorption of metal ions (Cu, Zn and Pb) compared with sand, packing wood, ash, zeolite and Enviro-media. The compost sorption of these metal ions conformed to the linear form of the Langmuir adsorption equation with the Langmuir constants (q,) for Zn(ll) being 11.2 mg/g at pH 5. However, compost was also found to leach a high concentration of dissolved organic carbon (DOC, 4.31 mg/g), compared with the other tested materials. Various combinations of sand, compost and other materials were observed to have excellent heavy metal removal (75-96% of Zn and 90-93% of Cu), with minimal DOC leaching (0.0013-2.43 mg/g). The sorption efficiency of the different Enviro-media mixes showed that a combination of traditional (sand) and alternative materials can be used as an effective medium for the treatment of dissolved metal contaminants commonly found in stormwater. The application of using recycled organic materials and other waste materials (such as recycled glass) also provides added value to the products life cycle.     

Influence of compost characteristics on heavy metal sorption from synthetic stormwater.

This paper has the aim to assess the ability of garden derived compost to remove dissolved heavy metal contaminants typically found in stormwater. Compost was found to have excellent chemical and physical properties for the sorption of dissolved metal ions (Cu2+, Pb2+ and Zn2+). Batch sorption data were used to determine the sorption efficiency of Cu (93%), Zn (88%) and Pb (97%) by compost. The relative sorption affinity of these metals by compost is found to be in the order of Pb2+ > Cu2+ Zn2+. The effect of different particle size fractions of compost upon the sorption of Cu was also investigated. Sorption conformed to the linear form of the Freundlich isotherm and can be considered favourable because the sorption intensity values obtained in this study are between 0.1 and 1. Compost with a smaller particle size fraction has larger surface areas and greater sorption than the larger particle size fraction. Compost derived from garden waste is efficient for removal of heavy metals from wastewater or treating water for industries.     

Co-precipitation of Ni, Cr, Mn, Pb and Zn in industrial wastewater and sediment samples with copper(II) cyclo-hexylmethyldithiocarbamate for their flame atomic absorption spectrometric determination

A co-precipitation technique for nickel(II), chromium(II), manganese(II), lead(II) and zinc(II) with the aid of copper(II) cyclo-hexylmethyldithiocarbamate was established. The influences of some analytical parameters such as pH, sample volume, amounts of cyclo-hexylmethyldithiocarbamate and copper(II) on the recovery of metal ions were investigated. The heavy metals in the precipitate were determined by flame atomic absorption spectrophotometry. The range of detection limits for the heavy metals was 0.003-0.005 mg/L. The atomic spectrometric technique with co-precipitation procedure was successfully applied for the determination of Ni, Cr, Mn, Pb and Zn in industrial wastewater and sediment samples from Ladipo stream in Lagos, Nigeria. The mean concentrations for these metals using co-precipitation procedure were not significantly different from corresponding concentrations obtained using spectrometric techniques without co-precipitation procedure.     

不同pH值条件下重金属捕集剂有效性的研究

采用高分子有机捕集剂与废水中的多种重金属离子发生螯合反应,生成稳定且不溶于水的金属螯合物来去除废水中的重金属离子。对4种捕集剂在不同pH值的条件下对含有汞、铜、镉、铅等重金属污水的去除效果进行了试验研究。结果表明,利用重金属捕集剂方法处理重金属废水的效率较高,有很好的应用前景。     

共存重金属离子对好氧活性污泥活性影响的实验研究

采用序批式实验研究了铜、锌、镍离子共存条件下,对活性污泥表观产率、生物吸附降解能力、污泥絮凝沉降性能和耗氧速率等方面的影响,并测定了两种重金属离子共存的情况下,不同浓度重金属离子之间的相互作用。实验结果表明:Cu2+和Zn2+、Cu2+和Ni2+、Zn2+和Ni2+3种离子共存总浓度分别为5、5、10 mg/L以内,对污泥表观产率的影响不是很大,系统可以稳定运行。3种离子共存总浓度分别为5、3、3 mg/L以内,对CODCr的去除率没有影响,MLSS都可以稳定的增加,大于这个基点,系统都无法正常的运行;Cu2+和Ni2+共存的情况下对微生物的呼吸有协同抑制的作用。     

The influence of heavy metals on the production of extracellular polymer substances in the processes of heavy metal ions elimination.

Wastewaters from a chemical industry polluted by heavy metal ions represent a hazard for all living organisms. It can mean danger for ecosystems and human health. New methods are sought alternative to traditional chemical and physical processes. Active elimination process of heavy metals ions provided by living cells, their components and extracellular products represents a potential way of separating toxic heavy metals from industrial wastewaters. While the abilities of bacteria to remove metal ions in solution are extensively used, fungi have been recognized as a promising kind of low-cost adsorbents for removal of heavy-metal ions from aqueous waste sources. Yeasts and fungi differ from each other in their constitution and in their abilities to produce variety of extracellular polymeric substances (EPS) with different mechanisms of metal interactions. The accumulation of Cd(2+), Cr(6+), Pb(2+), Ni(2+) and Zn(2+) by yeasts and their EPS was screened at twelve different yeast species in microcultivation system Bioscreen C and in the shaking Erlenmayer's flasks. This results were compared with the production of yeast EPS and the composition of yeast cell walls. The EPS production was measured during the yeast growth and cell wall composition was studied during the cultivations in the shaking flasks. At the end of the process extracellular polymers and their chemical composition were isolated and amount of bound heavy metals was characterized. The variable composition and the amount of the EPS were found at various yeast strains. It was influenced by various compositions of growth medium and also by various concentrations of heavy metals. It is evident, that the amount of bound heavy metals was different. The work reviews the possibilities of usage of various yeast EPS and components of cell walls in the elimination processes of heavy metal ions. Further the structure and properties of yeasts cell wall and EPS were discussed. The finding of mechanisms mentioned above is necessary to identify the functional groups entered in the metals elimination processes.     

Application of ionic liquids for the removal of heavy metals from wastewater and activated sludge

This paper presents the results of adsorption studies on the removal of heavy metals (Cr, Cu, Cd, Ni, Pb and Zn) from standard solutions, real wastewater samples and activated sewage sludge using a new technique of liquid-liquid extraction using quaternary ammonium and phosphonium ionic liquids (ILs). Batch sorption experiments were conducted using the ILs [PR4][TS], [PR4][MTBA], [A336][TS] and [A336][MTBA]. Removal of these heavy metals from standard solutions were not effective, however removal of heavy metals from the industrial effluents/wastewater treatment plants were satisfactory, indicating that the removal depends mainly on the composition of the wastewater and cannot be predicted with standard solutions. Removal of heavy metals from activated sludge proved to be more successful than conventional methods such as incineration, acid extraction, thermal treatment, etc. For the heavy metals Cu, Ni and Zn, ≥90% removal was achieved.     

Removal of lead(II) and copper(II) from aqueous solution using foitite from Linshou mine in Hebei, China

Foitite from Linshou mine in China's Hebei province was investigated as an adsorbent to remove Pb(II) and Cu(II) from aqueous solution. The results showed that foitite can readily remove heavy metal ions from aqueous solution. The data shows that the metal uptake for Pb(II) increases rapidly, accounting for 74.47% when contact time was 2 min. In contrast to Pb(ll), there was a worse capability for adsorption of Cu(II). In the first 4 min, the metal uptake accounted for 34.7%. According to the analytical results obtained from X-ray diffraction, laser Raman spectrum, X-ray energy dispersive spectrometer, and Zeta potential, the removal mechanism of Pb(II) and Cu(II) by using foitite can be explained as following: firstly, the existence of an electrostatic field around foitite particles can attract heavy metal ions and consequently combine heavy metal ions with OH; secondly, heavy metal ions in the solution are exchanged with the Fe3+ and Al3+ in the foitite.     

南昌市湖泊重金属源识别及污染特征风险评价

为了解南昌市湖泊重金属污染特征现状,论文以青山湖、象湖及前湖为研究对象,在分析湖泊水体及沉积物重金属Cr、Ni、Cu、Zn、Cd、Pb水平的基础上,采用因子分析、地质累积指数与综合潜在生态风险指数对湖泊重金属污染水平进行评价,并结合主成分分析等统计方法判别各研究水域重金属污染源。结果表明水域中Cr、Cd与Pb为主要重金属污染元素,前湖面临着最为严重的水体重金属污染。沉积物中Ni、Cu、Zn、Cd、Pb存在不同程度风险,各湖泊中沉积重金属风险程度从大到小均为Cd>Cu>Pb>Ni>Zn。前湖生态风险程度最大,其次是象湖。主成分分析表明湖泊重金属主要来源于交通运输与废水废气排放。因此为避免进一步污染,应合理规划交通,控制汽车尾气排放,提升污水治理水平。