潜流人工湿地处理微污水效能研究

构建4种潜流人工湿地处理微污染水,结果表明:出水各污染物均达到《地表水环境质量标准》Ⅲ类标准要求;芦竹湿地对污染物平均去除率相对较高;芦竹湿地启动阶段和稳定阶段对污染物去除存在显著性差异,美人蕉湿地和空白湿地对污染物去除率差异性不显著;填料种类对人工湿地中磷的去除率影响较大,不同填料不会影响启动时间。启动阶段和稳定阶段COD、TN、TP进水负荷和出水浓度都呈正相关关系,但是对COD启动阶段复相关系数小于稳定阶段复相关系数,对TP却相反,对TN两个阶段复相关系数变化不大。

浅析人工湿地技术在城市微污水体处理中的应用

伴随着城市化进程的不断推进,人们的生活水平大幅度提高,对城市生态环境的要求也越来越高,城市污水就是首要的处理问题,通过实践证明,人工湿地技术能有效发挥自身优势,科学地处理城市污水,因此,本文主要分析人工湿地技术在城市微污水体处理中的具体应用,包括其优势以及管理措施。

一体式膜生物反应器处理微污染污水的工程应用

工程使用的一体式膜生物反应器是针对微污染污水进行深度处理,实现废水资源化的高效工艺。应用表明,经膜生物反应器处理,系统运行稳定,出水水质优于城市污水再生利用城市杂用水水质标准(GB/T18920-2002),可直接用于城市绿化、冲厕、扫除及洗车。具有良好的环境、经济和社会效益。

富营养污水简易集成治理方法研究

以粉煤灰制成空心多功能污水处理材料,用该污水处理材料填充成五级絮凝降解过滤箱,在曝气协同下组成集吸附絮凝过滤与化学降解于一体的富营养水处理系统。在富营养水流量、曝气量分别为60L/h、40L/ m^3·h的工艺条件下,富营养水的可溶性盐、色度、COD_(cr)、BOD_5、氨氮、总磷等主要污染物指标分别降低93%、90%、95%、90%、86%和92%。该富营养水处理系统具有处理效果好、工艺简单和结构紧凑的特点。

复合透水材料在处理微污染水中的应用

海绵城市建设中传统透水材料对于雨水、生活污水等微污水净化能力甚微。使用废弃物制备的复合透水材料具有吸附和催化能力,可推广于海绵城市地砖铺设,灵活应用于大部分微污染水净化环境,且透水材料无需占用额外城市空间,减少净水设施占据空间。采用废弃物制备复合透水材料,在解决农业废物处理的同时,增强了透水材料的净水能力,节能环保,能够有效净化微污染水。

成都市乡镇污水处理厂工艺方案探讨与选择

乡镇污水处理厂地理位置分散,经济条件较差,进水水质和水量波动较大,直接套用大型污水处理厂的处理工艺难以满足要求。介绍了几种适用于小城镇的污水处理工艺,并对其进行适用特点和经济性分析,在此基础上提出成都市乡镇污水处理厂的工艺方案选择建议。

江津四面山藻类植物调查

江津四面山的藻类植物共162种(含变种),隶属于68属、33科、7门。文章分析了头道河、响水滩,洪海和大窝铺的藻类区系,对其种类成分、生态分布等作了初步探讨。结果表明,四面山的藻类区系中,以硅藻为多,占藻类总数的41.98％,其次为绿藻,占38.89％,蓝藻占15.43％,其它藻类占3.70％。分析藻类组成成分表明,微污水带种类多于乙型中污水带种类。另外,四面山藻类还有一个山区冷水种类明显的特征。

离式螺纹泵解决超滤膜污染的探讨

当前解决超滤膜污染的主要方法是物理清洗方法和化学清洗方法。超滤膜污染是目前阻碍超滤膜技术推广与应用的主要原因。利用离式螺纹泵制造的微气泡将污水微气泡化,此时微气泡在超滤膜的周围不断地爆裂,由此可以减缓超滤膜污染。

Advances in Microbial Remediation on the Application of Heavy Metal Pollution in Agricultural Water Resources

Heavy metal pollution in agricultural water resources is very serious in re- cent years, resulting in large losses of the agricultural economy and endangering human life and health. Due to the advantages of low cost, high efficiency and less secondary pollution, microbial ramediation technology is widely used in the treatment of heavy metal pollution in agricultural water resources. At present, with the progress of modern biotechnology, microbial remediation of heavy metals in agricul- tural water resources has grown rapidly. The sources and status quo of heavy met- al pollution in agricultural water resources at home and aboard, and the principles of microbial remediation of heavy metals pollution in agricultural water resources were reviewed in this paper, as well as the several common microbial remediation technology of heavy metals in agricultural water resources. Additionally, the further research work of heavy metal contaminated agricultural water resources by microbial ramediation were prospected.

Drinking water and liver cancer *

AIM To study the relationship between mutagenicity of drinking water and incidence of liver cancer in high liver cancer incidence areas in Guangxi.

Preparation of New Poly Silicate Iron Coagulants and Their Coagulation Property on Micro-polluted Water

The sodium silicate, ferric chloride, ferrous sulfate, sodium chlorate and other common inorganic materials were used to synthesize two new poly silicate iron coagulants： Polysilicate Ferric Chloride （PFSiC） and Polymeric Ferric Silicate Sulfate （PFSiS）. Their coagulation effect on micro-polluted water was compared with the poly ferric choride （PFC） saled in the market. The results showed that turbidity, organic matter, total phosphorus, total nitrogen removal rate ofPFSiC, PFSiS coagulant were better than PFC on micro-polluted water treatment at the same dosage. The coagulation effect of PFSiC was the best. The surface morphology of three coagulants was observed by scanning electron microscopy （SEM）, and the coagulation mechanism was discussed preliminarily.

Heavy metal contamination, physico-chemical and microbial evaluation of water samples collected from chromite mine environment of Sukinda, India

Water samples from chromite mine quarry of Sukinda and its adjacent areas were analyzed for their heavy metal contamination along with physico-chemical and microbial contents. The chromite mine water samples possessed high concentrations of heavy metals in the order of Cr〉Fe〉Zn〉Ni〉Co〉Mn while ground water did not show any heavy metal contamination except Fe. Physico-chemical parameters of mine water samples showed deviation from those of normal water. Mine water harboured low microbial populations of bacteria, fungi and actinomycetes in comparison with mine adjacent water samples. The correlation of data between metals with physico-chemical parameters showed both positive and negative responses while that of metal and microbial population exhibited negative correlation. Bacterial strains isolated from chromite mine water exhibited high tolerance towards chromium and other heavy metals as well as antibiotics which could be used as an indicator of heavy metal pollution.

Performance of BAC process for treatment of micro-polluted water

Biological activated carbon (BAC) has been developed on the granular activated carbon by immobilization of selected and acclimated species of bacteria to treat the micro-polluted water. The BAC removal efficiencies for nitrobenzene, permanganate index, turbidity and ammonia were investigated. Effects of shock loading and SEM (Scanning Electron Microscope) observation on BAC were studied. Backwashing and its intensity of BAC were also discussed. The results showed that BAC took short time to start up and recover to the normal condition after shock loading. The shock loading studies showed that the removal efficiency of BAC was not completely inhibited even at high concentration of nitrobenzene. Backwashing performed once every 10-20 d, or an average of 15 d. Backwashing intensity was 12-14 L/(s·m2) with air and 3-4 L/(s·m2) with water.

Chemical and Organic Contamination of Phreatic Aquifer of Sidi Bouzid （Center West of Tunisia）

An understanding of the long-term changes in the nitrate and microbial contamination pattern of the groundwater of Sidi Bouzid （Centre West of Tunisia） is critical to conservation of drinking water in rural areas supporting mixed land-use activities such as cropping, livestock farming, and residence. The phreatic aquifer was revealed polluted by domestic disposals of the wastewaters in the urban zone. The average nitrate concentration in the groundwater of the east of the mioplioquaternary aquifer of Saddaguia （Sidi Bouzid） rose from 50 mg NO3- during 1996 to over 100 mg in 2003, which represents an increase of some 10 mg per year. Nitrate groundwater pollution during the period 1996-2003 was the result of the abusive use of fertilizers.In the cultivated zone, we must reduce the effects of the excessive use of the nitrogen fertilizers on the basis of monitoring soil once a year, managing water resources, rationalizing the use of the chemical substances. In urban zones, most of lost wells located in the perimeter reveal the gravity of the state of the aquifer. This last is organically polluted and requires an immediate action for the generalization of the purification network. We need to take into account the reality of under soil in all future planning＇s and arrangements. A scheme of sanitation seems necessary before all plans of arrangement. The extension of the sewer network must give the priority to the most vulnerable zones.

Study on the Genetic and Physiological Toxicity of Wastewater from a Pharmaceutical Factory Using Root Tip Micronucleus Technology of Vicia faba

ObjectiveThe aim was to assess genetic and physiological toxicity of wastewater from a pharmaceutical factory using root tip micronucleus technology of Vicia faba. MethodThe pollution of wastewater from a pharmaceutical factory was detected by using root tip micronucleus technology of Vicia faba, and the genetic and physiological toxicity of the wastewater to Vicia faba was assessed. ResultNon-processed wastewater had an extremely high level of biological toxicity; the cells were unable to live with the wastewater at a high concentration; the cells were able to grow with the wastewater at a low concentration, though the micronucleus ratio was extremely high. The processed wastewater had no significant impact on cell growth, but the micronucleus ratio was extremely high, showing that the processed water also had a high pollution index. ConclusionThe research could provide scientific references for the national treatment of wastewater from a pharmaceutical factory.

Dynamic Adsorption of Microwave Modified Attapulgite on Micro-polluted Phenol Wastewater

[Objective] The paper was to study the dynamic adsorption of microwave modified attapulgite on micro-polluted phenol wastewater. [Method] Cetyl trimethyl ammonium bromide （CATB） modified attapulgite was used to modify attapulgite, and conducted dynamic test on micro-polluted phenol wastewater. The dynamic charac- teristics of phenol removal were also studied. [Result] Attapulgite modified by CATB has strong adsorption ability on phenol in micro-polluted water, the phenol removal rate increased with the decrease of flow rate of wastewater. When pH value was 6- 8, phenol concentration in wastewater was 17.74 mg/L, flow rate was 2 m/s and ad- sorption time was 25 rain, the removal rate reached 93.07%. The modified atta- pulgite could be regenerated with alkali, and its adsorption ability after regeneration had no obvious decline. The dynamic adsorption process of phenol accorded with the first-order kinetic equation. [Conclusion] The study provided basis for further study on ＂organic matter removal in wastewater.

Molecular analysis of microbial community in a groundwater sample polluted by landfill leachate and seawater

Seashore landfill aquifers are environments of special physicochemical conditions (high organic load and high sa- linity), and microbes in leachate-polluted aquifers play a significant role for intrinsic bioremediation. In order to characterize microbial diversity and look for clues on the relationship between microbial community structure and hydrochemistry, a cul- ture-independent examination of a typical groundwater sample obtained from a seashore landfill was conducted by sequence analysis of 16S rDNA clone library. Two sets of universal 16S rDNA primers were used to amplify DNA extracted from the groundwater so that problems arising from primer efficiency and specificity could be reduced. Of 74 clones randomly selected from the libraries, 30 contained unique sequences whose analysis showed that the majority of them belonged to bacteria (95.9%), with Proteobacteria (63.5%) being the dominant division. One archaeal sequence and one eukaryotic sequence were found as well. Bacterial sequences belonging to the following phylogenic groups were identified: Bacteroidetes (20.3%), β, γ, δ and ε-subdivisions of Proteobacteria (47.3%, 9.5%, 5.4% and 1.3%, respectively), Firmicutes (1.4%), Actinobacteria (2.7%), Cyanobacteria (2.7%). The percentages of Proteobacteria and Bacteroides in seawater were greater than those in the groundwater from a non-seashore landfill, indicating a possible influence of seawater. Quite a few sequences had close relatives in marine or hypersaline environments. Many sequences showed affiliations with microbes involved in anaerobic fermentation. The remarkable abundance of sequences related to (per)chlorate-reducing bacteria (ClRB) in the groundwater was significant and worthy of further study.

Microbial Electrolysis Cells for Hydrogen Production

Microbial electrolysis cells(MECs)present an attractive route for energy-saving hydrogen(H2)production along with treatment of various wastewaters,which can convert organic matter into H2 with the assistance of microbial electrocatalysis.However,the development of such renewable technologies for H2 production still faces considerable challenges regarding how to enhance the H2 production rate and to lower the energy and the system cost.In this review,we will focus on the recent research progress of MEC for H2 production.First,we present a brief introduction of MEC technology and the operating mechanism for H2 production.Then,the electrode materials including some typical electrocatalysts for hydrogen production are summarized and discussed.We also highlight how various substrates used in MEC affect the associated performance of hydrogen generation.Finally we presents several key scientific challenges and our perspectives on how to enhance the electrochemical performance.

Variability of micropollutants and microorganisms in water distribution system

The variation of water quality in water distribution system was investigated with assimilable organic carbon (AOC)and trihalomethanes(THMs) used as assessment indexes. Bacterium was identified in water distribution. The result showed that there were pathogenic parasites in water distribution system. The variation of AOC is related to chlorine residual and bacterium activity, and AOC concentration decreased first and then increased with the extension of water distribution system. The formation of THMs was related to the consumption of chlorine inside the distribution system, and THMs concentration increased with the extension of water pipe line.

Elucidate the impact of particulates on aqueous pollutant sonication

The potential inhibition of particulates on sonication of aqueous pollutants was investigated. Sonodegradation of bromobenzene, bromophenolate ion, and 2,4,5-trichlorobiphenyl were studied in the presence of various types of particulates suspended in water. Particulates of three different diameters (10 nm, 15 μm, and 35 μm) and two types (silica and polyaromatic resin) were investigated over a wide range of concentrations (0.05 g/L to 10 g/L). The results demonstrated that particulates inhibited sonication only when the target compound sorbed on the solid during sonication and could not partition into cavitation bubbles. The inhibition of the sorbed molecules was almost complete, and relatively independent of the particle concentration within certain ranges. However, the complexity of sonochemistry and particulate-solute matrices precludes a simple universal prediction of the inhibition extent.