生物滴滤池在处理重油裂解制气废水中的应用

用多孔填料填充废水处理系统缺氧/好氧（A/O）工艺中的缺氧滴滤池,微生物挂摸之后构成三维的生物膜,处理可生化性差的重油裂解制气废水,不但能显提高废水的可生物降解性,BOD5/COD从进水0.16-0.25提高到出水时的0.24-0.45,而且降低废水中的COD和氨氮分别为4.76%-44.21%和1.93%-44.20%,同时能增强缺氧池的抗冲击能力和减毒作用,有利于后续的活性污泥好氧处理。     

一株高产淀粉绿藻——标志链带藻在废水中的培养及对氮磷的去除

为了研究标志链带藻(Desmodesmus insignis strain JNU24)在不同Na NO3浓度和不同废水浓度培养下的生长与代谢产物积累状况,评估标志链带藻对废水的处理能力,本研究利用柱状光反应器对标志链带藻进行培养,分别对4种Na NO3浓度的BG-11培养基和4种废水浓度培养下藻细胞的生物量、蛋白质含量、碳水化合物含量和淀粉含量进行了测定。结果显示,在BG-11培养基中,氮浓度为9.0 mmol/L时,藻细胞生物质浓度最高,达6.23 g/L;在废水培养下,未稀释的原废水实验组,其藻细胞生物质浓度最高,达10.31 g/L;75%废水培养下,藻细胞的淀粉含量最高(达50.9%),单位体积藻细胞淀粉含量和产率分别为4.86 g/L和405 mg·L~(-1)·d~(-1),且显著高于不同浓度Na NO3的BG-11培养基组。本研究还测定了标志链带藻对废水中氮、磷的去除效率,结果显示不同浓度废水培养下,氮、磷的去除效率最高可达90.8%和98.7%。基于柱状反应器中的最佳培养效果,以9.0 mmol/L Na NO3的BG-11培养基和75%废水于3.0 cm光径平板光生物反应器中进行室内扩大培养,结果显示在75%废水培养下,藻细胞生物质浓度达9.75 g/L,淀粉单位体积含量和产率分别达到4.75 g/L和230 mg·L~(-1)·d~(-1),且为9.0 mmol/L Na NO3的BG-11培养基培养的3倍。通过沉降特性分析发现,藻细胞收获90 min后均完全沉降,具有较强的沉降性能。本研究标志链带藻能够耐受废水中较高的氮、磷浓度,且对废水中氮、磷有显著的去除作用;该藻能利用废水中的营养成分积累较高的生物量和淀粉含量并且藻细胞能快速沉降,具有极高的经济价值和应用价值,是一株淀粉生产能力较高和废水处理能力较强的极具开发潜力的藻株。     

几种混凝剂用于处理制浆造纸综合废水的性能试验

利用烧杯混凝试验,通过改变pH值、药剂投加量等方法开展了一系列混凝试验,比较了一种新型聚合混凝剂硫酸铝聚合氯化铝对以木浆为主的制浆造纸厂的综合废水的处理效果.结果表明,在最佳pH值和投药量条件下,新型聚合混凝剂的处理效果最好.当pH为8.29,药剂投加量为175mg·L^-1时,即使不投加CPAM,处理后的废水COD_Cr去除率为87.4%,浊度去除率为96.4%,色度去除率为89.5%;出水COD_Cr和色度分别为90mg·L^-1左右和约32倍,均达到了广东省《水污染物排放限值》(DB4426-2001)第二时段的一级标准.     

圆红冬孢酵母利用生物乙醇废水-木薯粉水解液发酵产油

【目的】获得能够高效降解生物乙醇废水化学需氧量(COD)的圆红冬孢酵母菌株,评估废水初始COD浓度对驯化菌株生长的影响,将木薯粉生产微生物油脂和高浓度有机废水降解过程整合,以生物乙醇废水为水源制备生物乙醇废水-木薯粉水解液培养基,明确产油效率高、生物乙醇废水COD降解率高的初始还原糖浓度。【方法】采用在高浓度的生物乙醇废水中进行多次驯化的方法,获得能够适应废水环境的圆红冬孢酵母菌株;采用双酶水解法对加入乙醇废水中的木薯粉进行水解;采用重量法监测生物量浓度变化,采用酸热法提取油脂,重铬酸钾法监测COD,DNS法测定废水还原糖浓度,凯氏定氮法测定总氮,钼酸铵比色法测定总磷。【结果】通过驯化筛选得到一株能耐受高浓度生物乙醇废水的优势菌株Rhodosporidium toruloides D5。以未稀释的废水为培养基,驯化菌株的最终生物量浓度和COD降解率分别为3.8 g/L和75.0%。采用生物乙醇废水-木薯粉水解液发酵时,控制初始还原糖浓度低于30 g/L时,生物量浓度和油脂浓度随初始还原糖浓度的升高而升高,均在120 h时达到最高COD降解率,初始还原糖浓度对达到的最大COD降解率无明显影响,废水N、P去除率分别达到99%和92%以上。【结论】在未经稀释的高浓度生物乙醇废水中可获得较高的生物量浓度;采用高浓度生物乙醇废水-木薯粉水解液培养基发酵产油,初始还原糖浓度为30 g/L,可在保证高油脂产量的同时,实现废水COD的高效降解,有效回收利用废水中残余的N、P源,从而降低微生物油脂生产和废水处理成本,研究结果可为开发廉价微生物油脂生产技术提供有用的参考。     

生物丁醇重大科技成果转化项目花落联海

经联海生物化学有限公司与江南大学联合攻关,利用中国科学院上海生命科学研究院专利菌种技术共同完成的“面粉深加工废水发酵生产丁醇的绿色工艺技术”实现了5大突破：面粉深加工废水为原料,解决了面粉深加工行业资源再利用和废水环保问题;采用专利菌种和优化的发酵工艺,达到国际先进水平;采用多效集成节能蒸馏及废水处理集成技术,与传统工艺相比,每吨溶剂蒸汽消耗量由12t降为8t,耗水量由100t降为10t;废水培养酵母蛋白饲料后作为工艺水回用,达标排放,产生沼气和活性污泥送入锅炉产汽,实现循环经济与清洁生产;生产规模国内最大。     

一株耐盐反硝化细菌的筛选、鉴定和特性及其产物四氢嘧啶的检测

【背景】石化工业废水具有高盐含氮的特点,高盐度会对微生物代谢造成抑制,导致普通反硝化微生物难以在高盐环境下有效脱氮。【目的】筛选在高盐条件下仍能保持反硝化能力的菌株并研究其特性。【方法】富集筛选出一株耐盐反硝化细菌,对其进行生理生化特性和16S rRNA基因序列鉴定,对其生长条件进行优化并测定该菌株反硝化能力,对菌株在高盐环境下的产物进行定性定量分析。【结果】经鉴定菌株YA16-1为表皮短杆菌(Brevibacterium epidermidis),可对硝态氮进行反硝化作用,在盐度为3%、初始氮浓度为55 mg/L的条件下,18 h的硝态氮转化率达到97%;初始硝态氮浓度为250 mg/L时,24 h内硝态氮转化率达到100%。该菌株的最适生长条件为：2% NaCl,碳源为玉米芯粉,氮源为酵母粉,pH值为6.0,培养温度为30 ℃。菌株在盐度为2%-15%的培养基内生长良好。在15%盐度下,菌株通过产四氢嘧啶维持渗透压,产量为0.89 mg/mL。【结论】菌株YA16-1具有良好的耐盐能力和反硝化能力,在高盐废水处理、保护生态环境和四氢嘧啶的制备具有潜在的应用价值。     

以毒性鉴别评价法评价化工废水处理效果的研究

江苏省某化工厂废水处理设施进、出水经大型Sou（Daphnia magna）急性毒性试验的结果表明,废水在处理前、后均显示毒性。采用毒性鉴别评价的试验程序,对处理设施的进、出水进行了关键毒物的鉴别和评价。发现进水中存在的关键毒物为金属铜离子并共存多种金属和极性有机毒物,而出水中存在的毒物为酸性条件下易被氧化的有毒有机物。该废水处理工艺对废水毒性去除率为77.6%。由此可见,该处理工艺对金属离子有较好的去除,而对有毒有机化合物的去除效果不甚理想,因此,该厂生产工艺和废水处理工艺还有待进一步改进。     

耐热脱氮菌株的分离鉴定及性能研究

[目的]为了解决高温的煤化工废水生物脱氮效率不高的技术难题。[方法]本研究从上海某能化集团有限公司的煤化工废水处理系统的活性污泥中筛选得到一株耐热氨氧化细菌A1和一株耐热反硝化细菌D1。[结果]通过形态学观察、生理生化特征及16S rRNA基因序列分析,菌株A1初步鉴定为Aquamicrobium ahrensii,菌株D1初步鉴定为Pseudomonas stutzeri。采用单因子优化实验研究发现,菌株A1和D1的最适生长温度分别高达42℃和40℃。在模拟实际废水处理的初始NH₄⁺-N浓度100 mg/L和42℃的条件下,构建了由菌株A1和D1 (W/W,20%/10%)组成的共培养物,探究该共培养物在不同pH和C/N对短程硝化反硝化脱氮及N₂O的释放效应。结果表明,该共培养物在42℃、pH 9.0–10.0和初始C/N为2:1时,处理模拟废水的氮素去除率达>99.0%,最大N₂O得率高达51.3%。[结论]本研究的结果可为高温煤化工废水的生物处理提供技术支撑及菌种储备,同时也为高温污水处理过程中N₂O的释放规律提供理论参考。     

2种小球藻在鱼糜加工废水处理过程中的生长和油脂积累规律

以小球藻Chlorella pyrenoidsa F-9和C.vulgaris HYS-2为材料,研究小球藻在鱼糜加工废水中的生长速率、脂类积累规律和对氮磷营养的消除效果。结果表明,2种小球藻在鱼糜加工废水中快速生长,最高生物量达到0.293 g/L和0.276 g/L,分别是f/2对照培养基的2.4和1.6倍。小球藻HYS-2在鱼糜加工废水中油脂百分含量最高达到36.22%,为对照培养基的1.27倍,小球藻F-9在鱼糜加工废水中的油脂含量达到17.89%,为f/2培养基中的0.89倍。培养15 d后,2种小球藻对鱼糜加工废水中氮磷去除率均达90%以上。以上研究表明,用未经任何化学处理的鱼糜加工废水养殖小球藻在生长速率上远远大于f/2培养基,说明其具有较好地发展潜力,可以实现微藻的低成本养殖。     

利用Chlorella vulgaris C9-JN2010去除蓝藻-猪粪沼液废水中氮磷的研究

利用普通小球藻Chlorella vugaris C9-JN2010处理蓝藻-猪粪沼液废水,以实现废水无害化利用。实验考察了氮磷比和沼液浓度对小球藻生长及处理废水效果的影响,结果表明:在氮磷比(20:1)和沼液浓度(5%)条件下培养小球藻,藻细胞生长和废水处理效果最佳,最高细胞干重及生产强度分别为900.1 mg·L~(-1)和85.1 mg·L~(-1)·d~(-1),废水中总氮、总磷、氨氮的去除率分别为84.6%、95.9%和90.5%,对应去除强度分别为5.43 mg·L~(-1)·d~(-1)、0.30 mg·L~(-1)·d~(-1)和4.75 mg·L~(-1)·d~(-1)。利用小球藻可较彻底的去除蓝藻-猪粪沼液废水中氮、磷等营养,达到污水处理效果。     

沼泽红假单胞菌(Rhodopseudomonas palustris)CQV97对无机三态氮共存水体中氮素的去除效率及其影响因素

研究水体环境因素(温度、光照和pH)、小分子有机碳和有机氮化合物对一株具有高效脱氮潜力的沼泽红假单胞菌(Rhodopseudomonas palustris)CQV97在无机三态氮共存体系中脱除无机三态氮的影响规律。结果显示,该菌株在20~40℃,500~5 000lux,pH 6.0~9.0环境条件下,能够脱除高浓度无机三态氮(其中亚硝氮不低于40mg·L-1),表明该菌株具有较强的适应复杂环境的能力;以乙酸钠/乙醇为唯一碳源时,该菌株能有效地去除无机三态氮,而以葡萄糖为唯一碳源时,能有效去除硝氮,但不能去除氨氮,亚硝氮明显积累,表明环境中小分子有机碳源影响菌体对无机三态氮的去除能力;体系中添加高浓度(120mg·L-1)蛋白胨或尿素时,由于有机氮降解的释氨作用,菌体对氨氮的去除能力受到明显抑制,氨氮积累明显,13d时氨氮去除率仅分别为16%(蛋白胨)和6%(尿素),但硝氮和亚硝氮的去除能力并没有受到明显影响。异位处理实际水体结果表明,菌株可使水体中氨氮含量明显降低、硝氮和亚硝氮被完全去除。综上,沼泽红假单胞菌CQV97菌株环境适应能力强,具有高效脱除水体无机三态氮的应用潜力,这为进一步开发高效脱氮微生物制剂及其合理使用奠定了基础。     

Anaerobic treatment of cassava starch extraction wastewater using a horizontal flow filter with bamboo as support

Small-scale sour starch agroindustry in Colombia suffer from absence of water treatment. Although starch processing plants produce diluted wastewater, it is a source of pollution and cause environmental problems to the nearby rural population. A laboratory scale anaerobic horizontal flow filter packed with bamboo pieces was evaluated for the treatment of cassava starch extraction wastewater. The wastewater used in the experimentation was the draining water of the starch sedimentation basin. The reactor was operated for 6 months. It was inoculated with a semi-granular sludge from an anaerobic UASB reactor of a slaughterhouse. Maximum organic loading rate (OLR) applied was 11.8g COD/L d without dilution of the wastewater. At steady state and maximum OLR applied, 87% of the COD was removed and a gas productivity of 3.7L/L d was achieved. The average biogas yield was 0.36L/g COD removed. Methane content in the biogas was in the range of 69-81%. The total suspended solids (TSS) removed were 67%. The relative high lactic acid content did not negatively influence the performance of the reactor. No perturbation due to cyanide (3-5mg/L) was observed during the reactor operation. The results obtained indicated that the anaerobic horizontal flow filter could be used efficiently for the treatment of wastewater from Colombian starch processing small-scale agroindustry.     

The pilot study for waste oil removal from oilfields by <Emphasis Type="Italic">Acinetobacter johnsonii</Emphasis> using a specialized batch bioreactor

The batch bioreactor with a maximum capacity of 0.28 m³ was designed and manufactured according to oilfield conditions Acinetobacter johnsonii ioslated from waste oil in an aerobic environment was employed to cleanse waste oil and wash-down water using the bioreactor in a pilot scale. The aerating process was optimized from 2 to 4 m³/h corresponding to the different cell growth phases, ensuring sufficient dissolved oxygen and avoiding cell damage from the shearing forces due to strong aeration. The bio-treatment of waste oil underwent two stages:one was the wettability reversal of inorganic admixtures from oil phase into waster phase through enlarged wetting angles, and the other was the bio-flocculation in waster phase by intermediate metabolites excreted by cells. Finally, inorganic admixtures were effectively removed from waste oil and wash-down water at the optimal conditions, with the content less than 0.5% in oil phase and turbidity and sulfide less than 100 NTU and 1 mg/L in the water phase, respectively. Such bio-treatment made the oil-water interface clear against oil and water emulsification and in favor of smooth reclamations for waste oil and wash-down water.     

Bioremoval of lead from water using Lemna minor

This study examined the ability of duckweed (Lemna minor) to remove soluble lead from water. The duckweed was obtained from the Devils Lake wastewater treatment plant in North Dakota. The viable aquatic plants were exposed to a single dose of lead (from Pb(NO₃)₂) at a concentration of 5.0 mg/l for a time period of 21 days. Lead concentrations were measured in the water daily and in the biomass at the conclusion of the experiment. All measurements were done in triplicate and performed in accordance with standard methods. These data were used to calculate the removal efficiency with respect to time, and to provide the necessary empirical constants to model the removal behavior. Viable biomass removed 85–90% of the lead, viable duckweed previously exposed to lead removed 70–80% of the lead, non-viable biomass (control group) removed 60–75% of the lead, and there was no removal in the ‘no-biomass' control group. Based on these results we conclude that the viable biomass is effective in removing lead present at sub-lethal levels.     

Removal of micro-organisms in a small-scale hydroponics wastewater treatment system

Aims: To measure the microbial removal capacity of a small-scale hydroponics wastewater treatment plant. Methods and Results: Paired samples were taken from untreated, partly-treated and treated wastewater and analysed for faecal microbial indicators, i.e. coliforms, Escherichia coli, enterococci, Clostridium perfringens spores and somatic coliphages, by culture based methods. Escherichia coli was never detected in effluent water after >5.8-log removal. Enterococci, coliforms, spores and coliphages were removed by 4.5, 4.1, 2.3 and 2.5 log respectively. Most of the removal (60-87%) took place in the latter part of the system because of settling, normal inactivation (retention time 12.7 d) and sand filtration. Time-dependent log-linear removal was shown for spores (k = -0.17 log d(-1), r(2) = 0.99). Conclusions: Hydroponics wastewater treatment removed micro-organisms satisfactorily. Significance and Impact of the Study: Investigations on the microbial removal capacity of hydroponics have only been performed for bacterial indicators. In this study it has been shown that virus and (oo)cyst process indicators were removed and that hydroponics can be an alternative to conventional wastewater treatment.     

Tertiary activated carbon treatment of paper and board industry wastewater

The feasibility of activated carbon post-treatment of (biologically treated) wastewater from the paper and board industry was investigated, the goal being to remove refractory organic pollutants and produce water that can be re-used in the production process. Because closing water-circuits in the paper and board industry results in higher water temperatures, the effect of the temperature on activated carbon treatment was also investigated. Batch and column adsorption tests showed that activated carbon provides an excellent removal of cationic demand and color related compounds, the two most important representatives of organic compounds that have to be removed. Unexpectedly, higher water temperatures enhanced the performance of activated carbon. However, the treatment costs, mainly determined by transport and regeneration of the carbon, were very high. At long contact times between the wastewater and the carbon the occurrence of biodegradation was observed. Biological regeneration of the carbon may therefore provide a means to reduce the treatment costs, but a practical application requires further research.     

Chitin: a potential new alternative nitrogen source for the tertiary,algal-based treatment of pulp and paper mill wastewater

Every day, pulp and paper mills in the USA discharge millions of liters of wastewater. Primary and secondary treatment of this wastewater often enriches it with phosphorus, resulting in uncontrolled eutrophication of receiving water bodies. A new method of tertiary wastewater treatment uses controlled growth of algae in a photobioreactor to sequester phosphorus into algal biomass, which is then harvested. This typically requires addition of a nitrogen fertilizer (nitrate, ammonium, or urea) to the water. We show on the laboratory scale that chitin can be used as an alternative source of nitrogen for the tertiary treatment of pulp mill wastewater using algae. We demonstrate that phosphorus can be efficiently removed from pulp wastewater using algae and chitin. Furthermore, phosphorus removal with chitin did not result in an increase in dissolved nitrogen in the wastewater because it is insoluble, unlike conventional nitrogen fertilizers. Despite its insolubility, it has recently been found that many diverse algae and cyanobacteria can use it as a source of nitrogen. Chitin has many advantages over conventional nitrogen fertilizers for use in wastewater treatment technologies. It is the second-most abundant natural polymer and is a waste product of the shellfish industry. Chitin is sustainable, inexpensive, and carbon neutral. Thus, chitin improves the sustainability and carbon footprints associated with water treatment, while the production of commercially attractive algal biomass helps to offset costs associated with the water treatment system itself.     

Bioaccumulation of mercury from wastewater by genetically engineered Escherichia coli

Genetically engineered E. coli, which express both a Hg2+ transport system and metallothionein, were tested for their ability to remove mercury from wastewater. The wastewater contained more than ten different ions, including 2.58 mg/l mercury, and its pH was 9.6. Mercury uptake was faster from the wastewater than from distilled water, probably because of the higher ionic strength, as the high pH had little effect on mercury accumulation. EDTA also stimulated mercury uptake rather than inhibiting it. A hollow-fiber bioreactor was used to retain induced cells for continuous mercury uptake. The cells removed more than 99% of the mercury in the wastewater and the final amount of mercury accumulated was 26.8 mg/g cell dry weight, while none of the other ions were removed from the water. These results indicated that the induced cells had a high affinity and specificity for mercury.     

An enzymatic method for removal of phenol from industrial effluent

Phenols in an aqueous solution were removed after treatment with peroxidase in the presence of hydrogen peroxide. Phenols occur in wastewater of a number of industries, such as high temperature coal conversion, petroleum refining, resin and plastic, wood and dye industries, etc. It can be toxic when present at elevated levels and is known to be carcinogeneous. Thus, removal of such compound from these industrial effluents is of great importance. An enzymatic method for removal of phenols from industrial wastewater, using turnip peroxidase, has been developed. Phenol-containing industrial wastewater was treated with immobilized turnip peroxidase in the presence of hydrogen peroxide. In the reaction, a number of phenols are oxidized to form the corresponding free radicals in the presence of hydrogen peroxide as an oxidant. Free radicals polymerize to form substances that are less soluble in water than the original substances. The precipitates were removed by conventional methods and residual phenol was estimated. The present report describes the immobilization of turnip peroxidase on silica via covalent coupling, and its utility in phenol removal. A comparative study was also carried out with other immobilization techniques, viz., calcium alginate entrapment, polyacrylamide gel entrapment, etc. Peroxidase, covalently bound to silica, showed 95% removal of phenol, whereas naphthol was removed up to 99%.     

Performance of Dead Azolla filiculoides Biomass in Biosorption of Au from Wastewater

Dried milled biomass of Azolla filiculoides removed up to 98.2% of gold from wastewater from a gold plating factory containing 5 mg gold/l in solution in batch biosorption. The gold uptake capacity of the biomass was 98 mg/g. Whole dried biomass used in a continuous flow column removed up to 100% of gold from diluted wastewater. A similar column was linked to a sulphide precipitation process to provide a two-step system which was able to remove 98% of gold from undiluted wastewater containing 41 mg Au/l. The lifetime of the column was five days.