CONCAVE BIOLOGICAL SURFACES FOR STRONG WET ADHESION

Plant leaves, insects and geckos are masters of adhesion or anti-adhesion by smartly designed refined surface structures with micro- and nano- ＇technologies＇. Understanding the basic principles in the design of the unique surface structures is of great importance in the manufacture or synthesis of micro- and nano- devices in MEMS or NEMS. This study is right inspired by this effort, focusing on the mechanics of wet adhesion between fibers having concave tips and a flat substrate via capillary forces. We show that the concave surface can effectively enhance the wet adhesion by reducing the effective contact angle of the fiber, firmly pinning the liquid bridge at its circumferential edge. A critical contact angle is identified below which the adhesion strength can achieve its maximum, being insensitive to the contact angle between the fiber and liquid. The analytical expression for the critical angle is derived. Then a tentative design for the profile of concave surfaces is proposed, considering the effects of chamfering size, deformation and buckling, etc. The effect of liquid volume on the wet adhesion of multiple-fiber system is also discussed.

Removal of disinfection by-products formation potential by biologically intensified process

The removal of disinfection by-products formation potential(DBPFP) in artificially intensified biological activated carbon(IBAC) process which is developed on the basis of traditional ozone granular activated carbon was evaluated. By IBAC removals of 31% and 68% for THMFP and HAAFP were obtained respectively. Under identical conditions, the removals of the same substances were 4% and 32% respectively only by the granular activated carbon(GAC) process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. A clear linear correlation(R 2=0.9562 and R 2=0.9007) between DOC HAAFP removal rate and Empty Bed Contact Time(EBCT) of IBAC process was observed, while that between THMFP removal rate and EBCT of GAC was R 2=0.9782. In addition certain linear correlations between THMFP, HAAFP and UV 254 (R 2=0.855 and R 2=0.7702) were found for the treated water. For IBAC process there are also more advantages such as long backwashing cycle time, low backwashing intensity and prolonging activated carbon lifetime and so on.

Biological removal of methanol from process condensate for the purpose of reclamation

The biological removal of methanol from condensate of ammonia manufacturing processes for the purpose of reclamation using contact type reactor was studied. Methanol of 60 mg/L was removed completely under an HRT of 1 12 h. Optimal inorganic nutrient dose was determined on evaluating methanol removal performance and dehydrogenase activities(DHA) under different nutrition doses. The optimal inorganic nutrient dose only gave an increase of conductivity of ca. 10 μs/cm 2 in the effluent on treating synthetic condensate containing methanol of 30 mg/L. The results demonstrated that biological removal of methanol was effective for the purpose of recovering the methanol bearing condensate.

Superior drainage treated by combinational technique of biologic contact oxidation and constructed wetland

The superior drainage was pre-treated by biologic contact oxidation on BOD5 load of 0.72 kg/(m3·d),and then post-treated by constructed wetland. The results about the effect on the constructed wetland post-treatment show that the total nitrogen (TN) is the restrictive index of the combinational technique treatment effect. To meet the reclaimed water quality standard and reuse for waterscape,the peak hydraulic load of constructed wetland is 0.50 m/d in summer (30-36 ℃) and 0.33 m/d in winter (8-12℃),and the load ratio of the peak hydraulic under the two temperature conditions is 3-2. The results are combined of reclaimed water quantity requirements in different seasons of green building. Reasonable scale of the reclaimed water treatment systems can be determined. The treatment efficacy can be well predicted,and both the design and operations can be effectively guided,by which the reclaimed water treatment systems regard superior drainage as the source and are purified by combinational technique of contact oxidation and artificial wetland.

Removal of disinfection by-product formation potentials by biologically assisted GAC treatment

The object of this paper is to evaluate the removal of disinfection by-products formation potential by artificially intensified biological activated carbon（BAC） process which is developed on the basis of traditional ozone granular activated carbon （GAC）. The results show that 23.1% of trihalomethane formation potential （THMFP） and 68% of haloacetic acid formation potential （HAAFP） can be removed by BAC, respectively. Under the same conditions, the removal rates of the same substances were 12.2% and 13-25% respectively only by GAC process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. BAC process has some advantages such as long backwashing cycle time, low backwashing intensity and prolonged activated carbon lifetime, etc.

The Application of Biological Removal Technology Used on the Treatment of Groundwater with Low-Iron and High-Manganese

The characteristic of groundwater belongs to low iron but high manganese in Shenyang Hunnan New Developed Area.The first stage engineering of The WTP of Shenyang Hunnan industry Area were designed according the technology of aerated-contact oxidation,and the water quality couldn’t reach to the standard after the WTP putted into production,1996.

Correlations of Materials Surface Properties with Biological Responses

More than 50 years have passed since it was first recognized that the surface properties, and predominantly the surface energies of materials controlled their interactions with all biological phases via their spontaneous acquisition of proteinaceous “conditioning films” of differing degrees of denaturation but usually of the same substances within any given system. This led to the understanding that useful engineering control of such interactions could thus be manifested through adjustments to those surface properties, giving significant control and utility to the biomaterials developer without requiring detailed discovery of the biological specifications of the components involved. Thus, effective selection of adhesive versus abhesive (non-stick, non-retention) outcomes for such useful appliances as dental implants versus substitute blood vessels, or water-resistant bonded structures versus clean, nontoxic ship bottoms is now facilitated with little biological background required. A historical overview is presented, followed by a brief survey of the forces involved and most useful analyses applied. Utility for blood-contacting materials is described in contrast to utility for bone- and tissue-contacting materials, demonstrating practical uses in controlling cell-surface interactions and preventing biofouling. New research directions being explored are noted, urging applications of this prior knowledge to replace the use of toxicants.

生物接触氧化-潜流型人工湿地组合工艺处理农村生活污水的应用案例研究

以浙江省永康市某农村的生活污水处理及灌溉回用工程为例,对“生物接触氧化-潜流人工湿地”组合工艺处理农村生活污水的设计参数、运行效果和工程效益等进行了分析。该工程设计规模为30 m^(3)/d,研究期间实际处理规模12~20 m^(3)/d,出水中TP、NH_(3)-N、COD、BOD5、SS、粪大肠菌群等11项主要指标灌溉期(4月至10月)满足《农田灌溉水质标准》,作为该村苗木基地灌溉用水,非灌溉期(11月至次年3月)出水满足《浙江省农村生活污水处理设施水污染物排放标准》,作为该村荷花种植塘的用水。工程运行期间对TP、NH_(3)-N、COD、BOD_(5)、粪大肠菌群、阴离子表面活性剂、色度、SS和浊度的平均去除率分别为44.3%、65.3%、63.8%、61.7%、76.2%、65.7%、74.2%、54.3%和50.5%。

BER-BCO耦合工艺净化模拟微污染河水及除磷机理研究

针对传统生物膜法对微污染河水脱氮除磷效率不佳的问题,设计了电极生物膜耦合生物接触氧化(BER-BCO)装置,采用单因素敏感性分析方法评估了不同碳源、电流密度、水力停留时间、填料填充比对工艺脱氮除磷效果的影响,并通过红外光谱表征阳极附近沉淀物表面特征官能团,探究系统除磷机理。结果表明,在使用乙酸钠为碳源、电流密度为0.09 mA/cm^(2)、水力停留时间控制为24 h、填料比为40%的条件下,BER-BCO系统的脱氮除磷效能得到了显著优化;NH+4-N、TN、TP的去除率分别达到了83.10%、56.46%、97.93%;最终出水除TN外均优于《地表水环境质量标准》(GB 3838-2002)中Ⅳ类水质标准;红外光谱分析显示阳极附近形成的含磷沉淀物中含有Fe-O键、P-O键、Fe-OH键,表明铁阳极具有高效除磷的特性。

微氧生化-生物接触氧化法对癸二酸废水的处理特性研究

癸二酸废水属于典型难降解工业废水,废水处理难度大,且富含的高硫酸盐极易被还原为硫化氢释放,导致环境污染。采用微氧生化-生物接触氧化工艺处理癸二酸废水,考察其对难降解工业废水的处理特性。结果表明,当进水负荷逐渐趋于稳定,在进水COD 4500~5500 mg/L、挥发酚150~200 mg/L的情况下,经微氧生化-生物接触氧化工艺处理后,出水COD<400 mg/L,挥发酚<0.5 mg/L。系统中出水硫化物质量浓度均低于0.2 mg/L,表明系统内不易产生H2S。在微氧段构建及启动阶段,伴随着DO升高,出水浊度不断降低;当整体工艺连续稳定运行时,系统除浊率保持在70%~90%之间,表明整体工艺对降低出水浊度有很好的效果。系统中MLSS 6000~8000 mg/L,SVI 100~150 mL/g,表明系统中污泥沉降性较好。系统运行稳定性评价表明系统具有较强的抗负荷冲击能力和耐盐度变化能力,可广泛应用于难降解工业废水的治理中。

曝气生物滤池影响因素及脱氮除磷研究进展

曝气生物滤池(BAF)是一种集吸附、过滤和生物氧化为一体的新型污水生物处理技术。本文介绍了影响BAF运行效果的因素(如填料、水力负荷、气水比、反冲洗、C/N和温度等),综述了BAF在去除水中各类污染物质的最新研究进展,并就该工艺在有机及悬浮物去除、硝化除氨、脱氮除磷、耦合其他工艺等方面所具备的优势与不足进行了阐述,为BAF的发展与应用研究提供一定的科学参考。

生物法处理金矿含氰废水同步收金技术研究与应用

开展生物法处理金矿含氰废水同步收金技术研究,通过改良缺氧^(-)好氧生物处理工艺,成功驯化增殖了以硫杆菌、特吕珀菌、假单胞菌为主的CN^(-)、SCN^(-)高效降解菌群。在工业应用上,生物法对SCN^(-)、COD、CN^(-)、NH_(3)-N的平均去除率分别为99.99%、97.54%、93.92%和98.92%,处理后的出水各项污染物指标远低于《污水综合排放标准》(GB 8978—1996)一级标准。微生物在降解废水污染物的同时,通过自身的氧化、吸附、絮凝沉降等作用,对起始浓度低的混合含金废水进行金回收,金的回收率可达到91%,富集金品位300~400 g t,不仅深度处理了废水中各项污染物,同时回收了有价金属,是一种环境友好且无公害的含氰废水处理技术。

元宇宙技术下网络隔空性侵入刑之反思

元宇宙对世界的改变侧重于社会性的侧面,无论是融合现实还是脑机互联,元宇宙都无法改变人的生物属性,而建基于生物属性之上的身体行动,则属于元宇宙辐射力鞭长莫及的领域。性依托生命而存在,性侵也只能以生物身体为载体。性侵需要物理在场与身体在场,但由于元宇宙空间无法容纳肉身,而且隔空猥亵的论证无法替换至性侵,因而网络隔空性侵自始不可能。对元宇宙技术下网络隔空性侵的肯定论,依靠的是概念的混淆、共犯的忽略与法益侵害的嫁接,并没有真正实现网络隔空性侵与传统性侵的等价式论证。网络隔空性侵的命题抽离了生物身体,企图用高度接近现实的元宇宙和脑机互联设备诠释其危害性并进行等价处理,但由于底层逻辑已然改变,其注定无法成功。我国对网络隔空性侵有充足的刑法规范供给,并不存在规制漏洞,没有修法必要。进行场景还原后发现,网络隔空性侵实质上并未隔空,而是在场,造成此种偏差认知的原因是不当的事实归纳与规范适用。围绕元宇宙展开学术思考与前沿探索应着眼于具有社会价值的真问题,避免落入纯技术窠臼与偏颇的假问题泥淖。学术遐想不能脱逸社会现实,学术想象力也需要恪守边界意识,而作为生命存在的人与亘古不变的人性则是这面边界之墙的基石。

生物接触氧化法处理生活污水的试验

生物接触氧化法在生活污水处理中具有显著优势,以往应用的处理装置针对性不强,局限性较高。以填料塔反应器作为试验装置,展开利用生物接触氧化法处理生活废水的方法研究。采取试验设计方式,结合生物接触法处理生活污水的工艺特征及处理规律,分析各方面因素对生活污水处理的影响,通过试验得出可靠数据,为生活污水处理操作数据的合理调控提供参照,提升生活污水处理成效。

生物接触氧化耦合生物活性炭工艺处理高盐污水实验总结

针对炼化企业废水盐含量高、稳定达标处理难、能耗高等问题,提出了生物接触氧化-生物活性炭工艺。通过梯度提高进水盐含量的方法成功驯化出耐盐菌,启动了生物接触氧化单元,池中生物挂膜良好,脱氮除碳效果显著,出水COD(化学需氧量)可稳定控制在90 mg/L以下,总氮在15 mg/L以下。菌群分析结果表明,在高盐含量(高盐)废水环境中,接触氧化单元生物膜中菌群数量和多样性较接种污泥发生明显改变,主要功能菌为Thiovirga、Thauera、Flavobacterium、Gemmobacter、Hydrogenophaga等。在生物活性炭单元,通过耐盐高效菌剂与活性炭的有机结合,提高了该单元对进水COD波动的抗冲击能力,活性炭表面形成生物膜,系统运行稳定,可控制出水COD基本在60 mg/L以下,氨氮质量浓度在2 mg/L以下,总氮在15 mg/L以下。全流程以生物降解为核心,工艺流程短、运行成本低,为高盐污水的稳定达标处理提供了技术支撑。

芬顿-ABR厌氧-生物接触氧化法组合工艺处理化学合成制药废水的工程应用

化学合成制药废水具有有机物浓度高且成分复杂的特点,通过研究废水特征,探索一种高效稳定的处理工艺。以某工程为例,采用芬顿氧化-ABR厌氧-生物接触氧化法-混凝沉淀-活性炭过滤组合工艺,对工艺进行了详细介绍。化验结果显示,废水COD、BOD_(5)、SS、NH_(3)-N的质量浓度分别为5200~5400 mg·L^(-1)、1100~1250 mg·L^(-1)、180~200 mg·L^(-1)、50~60 mg·L^(-1)、色度为80~100度。经105 d系统调试,不断优化运行控制参数,出水COD、BOD_(5)、SS、NH_(3)-N的质量浓度分别达到180 mg·L^(-1)、30 mg·L^(-1)、10 mg·L^(-1)、20 mg·L^(-1)以下,色度达到10度以下,主要污染物指标可达到《化学合成类制药工业水污染物间接排放标准》(DB41/756—2012)中的B级标准。针对此类化学合成制药废水,采用芬顿-ABR厌氧-生物接触氧化法组合工艺,技术可行,具有良好的环境效益。

水解酸化+生物接触氧化在印染废水处理中的应用

为了更高效的处理印染废水中的污染物,采用水解酸化+生物接触氧化法对混合染料废水进行处理,研究各工艺阶段对废水处理的影响,且因印染废水中化学需氧量(COD)较高,重点考察COD的去除效果。结果表明,水解酸化阶段对COD的去除率为29.17%;进一步通过2级生物接触氧化后,COD去除率提高至90.92%;当流量为5 L/h,pH为7时,可实现COD的较高去除率即92.58%,且在一定程度上节约处理成本。该方法可实现对混合染料废水中COD、五日生化需氧量(BOD5)、色度以及氨氮的有效去除。

生物接触氧化+混凝沉淀组合工艺处理合流制水体的研究

安庆市某村镇排水管网系统不完善,雨污混接,旱季污水入河现象明显,造成穿过该村镇的河道成为黑臭水体,降低了周边居民的生活质量和河道生态系统的稳定性。将村镇污水截污纳管后进行旁路处理,因该河道周边用地紧张,本工程在充分利用河道空间且不影响行洪的前提下,在下游河道上建钢结构平台布置旁路处理设备。采用占地面积小、处理效率高的“生物接触氧化+混凝沉淀”组合工艺处理合流制水体,出水稳定达到准地表Ⅳ类水标准,处理后的中水部分返回上游作为河道生态补水,提升河道自净能力。

改性沸石+生物接触氧化处理氨氮实验研究

改性沸石吸附与生物接触氧化组合工艺在处理微污染水中氨氮方面,虽然已经取得了一定的研究成果,但对于组合工艺在不同类型微污染水体中的应用效果缺乏系统的研究。文中通过实验室规模的吸附和生物接触氧化实验,分析了不同操作条件下的氨氮去除效果,发现改性沸石可以有效提升氨氮的去除率,其中有机改性沸石表现最优,氨氮去除率高达98.5%,同时,生物接触氧化工艺中,曝气量和HRT的增加均能提高氨氮去除率,生物膜的成熟度也对去除效果有正面影响。

肉制品废水处理工程设计实例及分析

某肉制品加工企业主要生产产品包括腊肉制品、自热食品、休闲肉制品等,在其产品的生产加工过程中伴随着肉类清洗及加工废水的产生。项目要求出水水质达到《广东省水污染物排放限值》(DB44/26-2016)第二时段三级标准。对肉类加工废水水质的分析表明,这类废水的BOD5/CODCr的比值高达0.5左右,同时这类废水含有氮、磷等多种营养可供微生物生长和繁殖,适合于采用生化作为主,深度为辅组合工艺。因此,预处理采用浅层气浮,生化处理采用UASB+缺氧+接触氧化工艺,深度处理采用混凝沉淀过滤工艺。该组合工艺在运营过程中表现出良好的处理效果,出水稳定达标。