北京市畜禽养殖业污染治理模式探讨

由于北京市农业耕地资源有限、规模化养殖场集中、畜禽养殖业管理薄弱等原因,致使大量畜禽粪便随意排放和流失,破坏生态环境。为解决北京市畜禽养殖业污染问题,在概述畜禽粪污处理技术的基础上,根据北京市畜禽养殖业污染治理现状,分析其存在的主要问题,探讨了基于区域集中式粪污处理模式,并提出了相关规划与政策建议,为北京市畜禽养殖污染治理提供经济、可行的发展方向。     

“十二五”畜禽养殖污染减排问题及防治对策

对中国"十二五"前3年畜禽养殖业污染减排实践中存在的问题和面临的困境进行了分析和梳理,针对问题依据各地养殖现状核算了各区域耕地粪污承载负荷。据此提出种养结合是区域适宜的粪污治理思路,为地方政府与环境主管部门推进畜禽养殖污染防治和粪污资源化利用提出了建议。     

基于结构分解技术的内蒙古自治区规模化畜禽养殖业减排机制研究

运用结构分解技术(SDA),构建了内蒙古自治区规模化畜禽养殖业减排机制分析模型,将规模化畜禽养殖业COD和氨氮减排分解为规模效应、结构效应和技术效应,并根据模型测算了2011—2013年各种效应的数值。测算结果表明:COD和氨氮减排总效应分别为50.95%和63.41%,畜禽养殖污染排放增长趋势仍未改变;规模效应分别为77.10%和79.96%,即养殖规模扩张增加COD和氨氮的排放;结构效应分别为-0.51%和7.53%,说明养殖结构调整对COD减排有利,但未促进氨氮减排;技术效应分别为-25.64%和-24.08%,是COD和氨氮减排的主要驱动力;从养殖种类看,生猪、奶牛养殖技术减排是影响整体技术效应的关键,肉鸡养殖的污染物去除率有所降低,需要推动减排工程并加强监管。     

甘肃省高台县国家试点规模化生物天然气项目技术方案与实施

利用农业有机废弃物生产沼气及生物天然气(BNG)是解决我国农业面源污染问题的重要技术手段之一,而规模化生物天然气项目已成为行业发展方向。以甘肃省高台县国家试点规模化生物天然气项目工程案例为研究对象,探讨了工艺技术与设备、工程设计特点以及实施效果,分析了干秸秆"回流沼液+无机肥料"预处理的生物与化学机理、秸秆/粪污高浓度联合厌氧发酵控制因素、沼气水洗提纯在应用中技术优势。说明了2个原料通道、综合工艺管廊及寒冷区域节能等工程的设计思想。实践表明,工艺运行良好、系统稳定性高。实施"治理费+气-肥并举"的盈利模式后,项目进入良性运行轨道,可为我国规模化生物天然气行业发展提供技术和工程参考。     

UASB-SBR组合工艺处理畜禽养殖废水的研究

近年来,随着中国畜禽养殖业的快速发展,落后的养殖模式和污染防治设施,使畜禽养殖污染日趋严重,畜禽养殖污染已居农业污染源之首,已成为中国环境污染的重要因素,对环境质量乃至人体健康都会产生不良影响。文中采用UASB—SBR组合工艺处理畜禽养殖废水,通过试验探讨SBR反应器启动方法及最佳运行模式,同时研究UASB反应器的启动方法。结果表明,SBR运行的最佳模式为进水0.5 h、反应8 h、沉淀1 h、出水0.5 h、闲置14 h。经过一段时间的启动,UASB和SBR反应器均成功启动,UASB—SBR组合工艺在处理畜禽养殖废水时可获得稳定的处理效果,COD、氨氮、总磷等出水水质均达到《畜禽养殖业污染物排放标准》(GB18596-2001)要求,为畜禽养殖废水处理的工程化应用提供了参考依据。     

畜禽废弃物厌氧消化过程的氨氮抑制及其应对措施研究进展

氨氮抑制是造成畜禽养殖废弃物厌氧消化处理效率低和运行稳定性差的主要因素之一。在总结国内外研究进展的基础上,简述了氨氮的来源及抑制阈值,剖析了氨氮抑制的机理及其影响因素,从氨氮的缓冲和微生物驯化2个方面总结了氨氮抑制的应对措施。建议重点加强畜禽养殖废弃物厌氧消化过程中氨氮释放规律、"氨氮-VFAs-碳酸盐"三元缓冲体系的调控模式、氨氮抑制的微生物学机制等方面的研究,以期为提高畜禽养殖废弃物厌氧消化工程的处理效率和运行稳定性提供参考。     

规模化养殖场畜禽粪便发酵还田负荷估算及风险评价——以四川省邛崃市为例

以邛崃市为研究对象,结合其规模化畜禽养殖量、畜禽粪便排放量以及农作物氮肥需求量等,对研究区域耕地畜禽粪便最大氮负荷量进行了估算,将其与畜禽粪便发酵副产物沼渣沼液还田产生的实际氮负荷量进行比较,由此对现有养殖规模下的环境风险进行了评价.结果表明,当前邛崃市除孔明乡、火井镇、回龙镇受到沼渣沼液还田污染以外,其他各养殖区域沼渣沼液还田尚未造成明显污染.因此,邛崃市规模化养殖还存在较大的发展空间,但必须从实际出发,合理规划,才能实现农业和环境的可持续发展.     

畜禽养殖污染防治典型工程的综合效益评价

通过对我国畜禽养殖污染防治工程建设现状的调查和分析,拟定了我国畜禽养殖污染防治工程的评价指标体系,采用层次分析与灰色关联度分析相结合的综合评价方法,对国内的8个典型工程的综合效益进行了评价。评价结果表明,规模化及综合性的养殖污染防治工程可获得较好的综合效益,而在养殖污染防治中采用单一的沼气化处理,由于其经济性较差,目前尚不能获得较好的综合效益。     

基于多限量标准的县域尺度畜禽养殖适度规模及潜在规模估算——以安徽省为例

开展了不同限量标准下安徽省各县(市、区)的畜禽养殖适度规模及潜在规模估算。结果表明,不同限量标准下的畜禽养殖适度规模估算结果在空间上都呈现出从安徽省的西北部向东南部逐渐递减的趋势,但不同限量标准下的畜禽养殖适度规模估算结果存在差异。其中,畜禽养殖排泄物氮负荷量限量标准下的畜禽养殖适度规模估算结果最大,全省为15 781.33万头(以猪当量计,下同);畜禽养殖排泄物猪粪当量警报值限量标准下的畜禽养殖适度规模最小,全省为4 733.88万头。6种限量标准下的畜禽养殖潜在规模空间分布与畜禽养殖适度规模基本一致。畜禽养殖排泄物猪粪当量警报值限量标准下的畜禽养殖适度规模超限最严重,全省超限796.81万头,共有48个县(市、区)超限,其中超限最多的是肥西县(102.92万头),超限最少的是马鞍山市市辖区(0.29万头)。     

新西兰氮排放配额与交易制度对中国的启示——以奶牛养殖业为例

近年来,排污权有偿使用与交易制度在中国部分省份开展了试点工作,许多大型的规模化畜禽养殖场也进行了排污许可证的申领。针对新西兰奶牛养殖业的污染治理措施进行了研究,梳理其开展污染防治工作的措施体系,以陶泊湖周边施行的氮排放配额与交易为主要对象,阐述了新西兰在养殖业排放配额与交易制度方面的工作实践,其配额基准核定方法、"资源许可证"申领制度、配额交易体系、相关支撑措施在一定程度上具备优势和先进性,对中国的畜禽养殖污染减排工作具有借鉴意义。     

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).     

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。     

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。     

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     

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.     

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.