生物膜填料塔净化模拟烟气和电厂烟气中SO2和NOx的对比实验

对生物膜填料塔对模拟烟气和电厂烟气的净化效果进行了实验研究。实验对比分析了在相同的实验条件下生物膜填料塔对不同烟气中SO2和NOx的净化效率。实验结果表明,在循环液温度在24～35℃、空床停留时间（EBRT）为60s、喷淋量为8～10L／h、脱硫塔的pH为0．8～1．5、脱氮塔的pH为7．5～8．0的条件下,生物膜填料塔对模拟烟气和电厂烟气中SO2的净化效率都很高,但模拟烟气条件下的总脱氮率的平均值为80％,而在电厂烟气条件下只有35％。经分析认为,脱氮率产生差异的主要原因是电厂烟气中杂质的影响,以及烟气中氧气含量的不同,同时因为生长条件不同从而驯化出的微生物群体组成也不同。     

烟气同时脱硫脱氮生物膜填料塔的适用外加碳源

实验分别考察了外加乙酸钠、葡萄糖、酒石酸钾钠、甲醇等4种低分子有机碳源对生物膜填料塔烟气同时脱硫脱氮效率的影响。结果表明,外加乙酸钠的脱氮效果最佳,对NOx的平均去除率为62.05%;外加葡萄糖、酒石酸钾钠、甲醇时的NOx平均去除率分别为51.03%、46.98%、58.71%。乙酸钠、酒石酸钾钠、甲醇均能使SO2的去除率达到100%,葡萄糖显著降低了SO2的去除率。乙酸钠是在生物膜填料塔烟气同时脱硫脱氮技术中适宜的外加碳源。     

脱氮塔中一株异养硝化真菌的分离鉴定及其脱氮特性

在微生物净化燃煤烟气技术研究中,NO、NO_x的脱除效率不高,达不到工艺要求。国内外对于微生物法净化燃煤烟气NO、NO_x的细菌作用研究较多,而对真菌的作用却研究很少。为了提高微生物法对燃煤烟气NO、NO_x的脱除效率,对脱氮塔生物膜中的异养硝化作用真菌进行了分离、纯化及鉴定,通过摇瓶实验研究了真菌对亚硝酸盐(NO_2~-)的作用特征,在脱氮塔中对NO_x的脱除效率进行了实验验证。实验结果:从脱氮塔生物膜中分离纯化的真菌为木霉属的棘孢木霉Trichodema asperellum(简称:1LNL菌株);该1LNL菌株能直接将NO_2~-氧化为NO-3,在实验周期为10 d的条件下,细菌对照组硝化率为31.5%、空白对照组硝化率为8.4%,1LNL菌株的硝化率能达到25.0%,实验证明真菌1LNL菌株具有一定的硝化作用;将1LNL纯菌株扩大培养液400 mL投加到脱氮塔中,NO的脱除率平均提高了4.39%,NO_x的脱除率平均提高了4.00%,真菌1LNL能显著提高脱氮柱NO、NO_x的脱氮效率。在微生物净化烟气中NO、NO_x的研究实践中,真菌的作用应加以重视并应展开更加深入、系统的研究。     

碳源及反硝化芽孢杆菌强化低C/N比景观水体的生物脱氮

实验探讨了添加碳源及投加反硝化细菌对低碳氮比景观水体生物脱氮的影响。结果表明,有机碳源及B.subtilis FS05均能显著促进实验水体的生物脱氮作用,实验水体在28℃静置72 h后,乙醇添加组的TN、氨氮、硝酸盐及亚硝酸盐的去除率分别达到了62.7%、67.0%、69.8%和29.4%,而同样条件下,B.subtilis FS05投加组的去除率分别达到了66.9%、73.4%、66.0%和82.2%。从水质变化趋势可以看出,投加B.subtilis FS05能在更短时间内完成生物脱氮过程,其中,硝酸盐和亚硝酸盐去除速率最快,分别仅需要18 h和12 h。     

锅炉烟气联合脱硫脱氮技术

硫氧化物和氮氧化物是燃煤锅炉排放的主要污染物 ,传统分步脱硫脱氮设备昂贵且效率不高 ,而联合脱硫脱氮技术具有很大的优越性 ,如可以减小系统的复杂性、具有更好的运行性能、较低的成本及较小的占地面积 ,因此实现在一个系统内同时脱硫脱氮的工艺成为国内外烟气净化技术的研究重点。对近年来国内外各种联合脱硫脱氮技术的脱除原理、研究现状、应用情况和主要优缺点进行了论述 ,并对各工艺的经济技术指标给予了多方面的比较。通过对两类烟气联合脱硫脱氮技术 (炉内联合脱除和烟气中联合脱除 )的分析、综合和比较 ,找出了我国今后脱硫脱氮技术的研究重点 ,从而为脱硫脱氮技术的进一步开发和改进提供参考     

外源性海藻糖强化好氧脱氮菌处理高盐废水的菌群特性

为提升高盐胁迫下好氧脱氮功能菌群的富集丰度及脱氮性能,解决高盐废水生物脱氮效率低的问题,助推好氧脱氮功能菌在高盐废水处理的工程应用,将海藻糖添加到已富集好氧脱氮功能菌的膜曝气生物膜反应器(membrane aerobic biofilm reactor,MABR)中,构建高盐废水的海藻糖生物强化处理系统,从反应器脱氮性能、菌群多样性以及脱氮功能基因丰度等方面探究高盐废水中海藻糖对好氧脱氮菌的强化机制。结果表明：实验组(C₄₀、C₁₂₀、C₃₆₀和C_{1 080})中NH₄⁺-N、TN和COD去除率相较对照组(C₀)分别提高了10.70%、32.72%、27.36%、19.45%,8.32%、28.36%、22.53%、17.63%和12.09%、31.14%、25.27%、25.06%;外加海藻糖提高了菌群在高盐废水中的脱氮效率,浓度为120μmol·L^-1时,NH₄⁺-N...     

锅炉烟气联合脱硫脱氮技术

硫氧化物和氮氧化物是燃煤锅炉排放的主要污染物，传统分步脱硫脱氮设备昂贵且效率不高，而联合脱硫脱氮技术具有很大的优越性，如可以减小系统的复杂性、具有更好的运行性能、较低的成本及较小的占地面积，因此实现在一个系统内同时脱硫脱氮的工艺成为国内外烟气净化技术的研究重点。对近年来国内外各种联合脱硫脱氮技术的脱除原理、研究现状、应用情况和主要优缺点进行了论述，并对各工艺的经济技术指标给予了多方面的比较。通过对两类烟气联合脱硫脱氮技术(炉内联合脱除和烟气中联合脱除)的分析、综合和比较，找出了我国今后脱硫脱氮技术的研究重点，从而为脱硫脱氮技术的进一步开发和改进提供参考。     

复合菌剂强化处理高盐废水脱氮效果

将耐盐脱氮复合菌剂投加到序批式生物反应器中,构建生物强化高盐废水处理系统(SBR1),以未投加复合菌剂系统(SBR2)作为对照,分析典型周期中氮素和溶解氧的变化趋势以及盐度冲击对脱氮效果的影响.实验表明,在曝气时间为6h时,生物强化系统脱氮率可稳定在96％以上,出水总氮浓度为3.8 mg/L左右.反应中始终无硝氮、亚硝氮积累,生物强化系统具有同步硝化好氧反硝化能力.当受到5％和7％较高盐度冲击时,生物强化系统表现出优于对照系统的抗盐度冲击能力,能够快速恢复原有活性,且出水总氮低于15 mg/L;当受到0％盐度的淡水冲击时,对照系统中耐盐污泥失活且无法恢复,而生物强化系统只需投加少量(3％)耐盐脱氮复合菌剂,即可快速恢复活性,出水总氮低于15 mg/L.本研究能够为生物强化高盐废水脱氮系统的构建和运行提供技术支持.     

混合液回流比对MSBR工艺强化生物脱氮的影响

针对二级城镇污水处理厂提标改造时出水氮、磷指标很难同时达到一级A标准（GB18918-2002）的情况,提出了改良式序批式反应器（MSBR）的强化生物脱氮运行模式,并通过生产性实验研究了MSBR工艺混合液回流比（6单元回流至5单元）对出水COD、TP、NH4＋-N及TN的影响。实验结果表明,MSBR工艺混合液回流比对COD、NH4＋-N去除基本上没有影响,但对TN和TP去除有影响。当回流比从0提高1和1．5时,TP去除效率分别降低了5．85％和4．06％;而TN去除效率分别提高了10．46％和7．87％,同时出水TN可稳定达到一级A标的要求。从控制运行能耗和脱氮效果的角度综合考虑,该污水厂强化生物脱氮的混合液回流比控制在1是比较合适的。     

电气石强化序批式生物膜反应器脱氮效能研究

比较了含电气石的新型陶粒生物膜载体和普通陶粒生物膜载体组成的电气石强化序批式生物膜反应器(SBBR)工艺和普通SBBR工艺的脱氮效能。结果表明,新型陶粒生物膜载体具有更好的吸附性能和生物亲和性。单周期分析表明,电气石强化SBBR工艺中氨氮浓度明显低于普通SBBR工艺,同步反硝化作用也强于普通SBBR工艺,表明电气石强化SBBR工艺的的脱氮效果优于普通SBBR工艺。90d的稳定运行进一步证明了电气石强化SBBR工艺的脱氮性能优于普通SBBR工艺,而且COD和总磷的去除效果也优于普通SBBR工艺。     

Optimization of Height of Release of Air Pollutants

A number of key projects in the Environmental Protection Agency (EPA) particulate R&;D program having applicability to industry are presented. For electrostatic precipitators (ESP) there is presented the result of work on large diameter discharge electrodes which provide a decrease in penetration of up to a factor of 4 when compared to conventional small diameter electrodes. Also discussed is the multistage ESP which provides a collection efficiency that would require a collecting plate area 4 or 5 times larger with conventional ESP technology. The E-SOX technology makes use of the multistage concept to free up space in the ESP for SO₂ removals of up to 90%. Electrostatically augmented fabric filtration provides a reduction in pressure drop of about 5 0% as compared to conventional fabric filtration. Wind tunnel modeling of windbreaks for material storage piles indicates a potential for providing engineering design data that would allow significant emission reduction caused by wind erosion     

Investigation of the characteristics of the reflectivity of clouds

This paper investigates some of the reflectivity characteristics that clouds (when modelled as solid bodies) must exhibit to be compatible with observations that the reflecting surface of a cloud (i) appears almost equally bright across its face, (ii) is brightest when the cloud is opposite to the Sun but decreases in brightness as the cloud moves to other positions and (iii) increases in brightness with increasing optical thickness of the cloud in the observer's line of sight. These observations, respectively, are shown to imply that the peak value of the bidirectional total reflectivity from a cloud surface (i) increases in inverse proportion to the cosine of the angle between the Sun and the normal to the cloud surface, as the incident angle increases, (ii) appears to be directed back in the direction of the incident radiation, and (iii) increases as optical thickness of the cloud in the observer's line of sight increases. The results could have application in many fields (e.g. modelling diffuse radiance distributions for cloudy skies).     

实验室质量管理体系内部审核的实施

在实施ISO／IEC17025：1999标准《检测和校准实验室能力的通用要求》过程中，通过实验室质量管理体系内部审核的实践与系统分析，识别出内部审核实施阶段的关键环节，提出召开首次会议、收集审核证据、确定审核发现和召开末次会议的技术方法，对提高内部审核的质量和有效性、获得可靠的审核结论具有重要意义。     

An application of the theory of kinematics of mixing to the study of tropospheric dispersion

The most common technique used for numerical simulations of tracer mixing is that of the numerical solution of the advection–diffusion equation with the unresolved fluxes parameterized using the similarity theory. Despite correct predictions of the overall directions of transport, models based on a numerical solution of the advection–diffusion equation lack sufficient accuracy to correctly reproduce the coupling of mixing with small scale processes which are sensitive to the microstructure of the tracer distribution. The objective of this paper is to revisit the basic formalism employed in numerical models used to investigate atmospheric tracers. The main mathematical method proposed here is the theory of kinematics of mixing which could be applied effectively for simulations of atmospheric transport processes. At the beginning of the paper, we introduce simple mathematical transformations in order to demonstrate how complex topological structures are created by mixing processes. These idealistic flow systems are essential to explain transport properties of much more complex three-dimensional geophysical flows. An example of the application of the kinematics of mixing to the analysis of tracer transport on a planetary scale is presented in the following sections. The complex filamentary structures simulated in the numerical experiment are evaluated using some commonly applied statistical measures in order to compare the results with the data published in the literature. The results of the experiment are also analysed with the help of simple conceptual models of fluid filaments. The microstructure of the tracer distribution introduced in the paper is essential to increase our understanding of atmospheric transport and to develop more realistic parameterizations of small-scale mixing. The presented results could also be used to improve calculations of the coupling between microphysical processes and tracer mixing.     

Estimation of uncertainty of sampling for analysis of pesticide residues

Abstract

A computer model was used to take random samples from primary sample populations obtained from field trials to simulate the uncertainty of sampling for residue analysis of plant commodities and soil. The results indicate about 40%, 30% and 20% relative uncertainty when random samples of size 5, 10 and 25 are taken respectively, from a single lot. Therefore the sample size should be the same for establishing and enforcing legal limits.     

扬中生态环境建设的思考与实践

结合扬中生态环境的基本情况和存在的不足，进行了具体分析，对扬中未来生态建设的发展方向提出了建议及实施措施。     

次氯酸钠发生器的研制

介绍了电解法生产次氯酸钠的原理 ,并在原有生产工艺的基础上进行了重新设计和对设备的重新选择、改造 ,得出了各个工艺参数的最佳值 ,生产出高品质的次氯酸钠     

Comparison of methods for evaluation of activity of photocatalytic films

Objective

This work aims to investigate the correlation between the photocatalytic activity determined by methylene blue bleaching (DIN 52980), stearic acid degradation, and degradation of acetone in gas phase.

Method

The photocatalytic TiO₂ coatings included in this investigation ranged from thin commercially available coatings (Activ^TM and BioClean^TM) and ready to use suspensions (Nano-X PK1245) to lab-produced PVD and sol?Cgel coatings. XRD analysis of the photocatalytic coatings showed that all the coatings consisted of nanocrystalline anatase, although the thickness and porosity varied considerably.

Results

The study showed that the reproducibility of the activity measurements was good. However, more importantly, the investigation showed that there is a good correlation between the activities determined by the different methods even though the characteristics of the photocatalytic coatings and the organic probe molecules varied considerably.

Conclusion

The overall findings of this work suggest that there is a good correlation between the investigated methods. These results are promising for the future work concerning standardization of methods for determination of the activity of photocatalytic films.     

Impact of overexploitation of shellfish: northeastern coast of India

India has a very extensive coastline of about 7515 km, rich in diverse living resources. These resources continue to deteriorate with rampant harvesting or are altered for other uses such as aquaculture and fisheries. The present paper deals with degrading coastal habitats in northeastern India, and projects the intensity of the stress arising from the collection of tiger prawn seeds (Penaeus monodon) for aquacultural farms and molluskan shells for poultry feed and edible lime. Indiscriminate exploitation of these resources leads to a heavy reduction of the species concerned and other associated marine communities. The magnitude of such destruction has been quantified. The impacts of biodiversity loss and their after-effects on the ecobalance of this coastal system have become a matter of great concern to ecologists to maintain security and sustainability. The authors propose a public awareness program on themes relating to the importance of biodiversity for human livelihoods.