两种不同布水方式对生物砂滤池去除厌氧消化液氨氮的影响

在实验室条件下,采用试验生物砂滤柱模拟生物砂滤池系统,研究了雾化和滴渗布水方式对生物砂滤池去除猪场厌氧消化液氨氮的影响,结果表明:在进水水力负荷为0.057 m3.m-2d-1,氨氮平均浓度分别为293 mg.L-1,513 mg.L-1,553 mg.L-1时,雾化布水生物砂滤池对氨氮的平均去除率分别为98.8%,87.4%,75.1%,出水氨氮平均浓度分别为3.61 mg.L-1,64.7 mg.L-1,138 mg.L-1,平均去除负荷分别为16.4 g.m-2d-1,25.4g.m-2d-1,23.5 g.m-2d-1;滴渗布水生物砂滤池对氨氮的平均去除率分别为77.4%,71.4%,59.3%,出水氨氮平均浓度分别为66.3 mg.L-1,147 mg.L-1,225 mg.L-1,平均去除负荷分别为12.9 g.m-2d-1,20.7 g.m-2d-1,18.6 g.m-2d-1;雾化布水可以提高生物砂滤池氨氮的去除率、去除负荷,降低出水氨氮浓度;滴渗布水在进水氨氮平均浓度293 mg.L-1,雾化布水进水氨氮平均浓度293 mg.L-1,513 mg.L-1的条件下,出水氨氮平均浓度可达到《畜禽...     

UASB-接触氧化-絮凝沉淀工艺处理低浓度生活污水小试研究

采用UASB -接触氧化 -絮凝沉淀工艺处理低浓度生活污水的实验研究表明 ,在生物段总水力停留时间为 5 .8h ,其中UASB段 3.8h ,接触氧化段 2 .0h ,进水COD为 10 0～ 30 0mg·L-1时 ,平均CODCr和BOD5去除率分别可达 83.4 %和 92 .7%。系统耐冲击负荷能力强 ,剩余污泥产量极少 ,平均出水CODCr为 2 0 .1mg·L-1,平均BOD5为 3.2mg·L-1,浊度≤ 8NTU ,水质透明 ,无味 ,如果再加以深度处理 ,可以回用。     

低气温条件下两级曝气生物滤池的启动研究

研究了低气温条件下两级曝气生物滤池处理校园生活污水的启动条件。利用自制的两级曝气生物滤池,采用自然富集培养挂膜法对曝气生物滤池进行挂膜启动。设计试验时间为30 d,分析了挂膜期间SS、BOD_5、COD_(Cr)、NH_3-N和TP的去除效果,并监测了水温变化情况。试验结果表明,在新疆冬季低气温条件下,用自制的具有加热保温功能的曝气生物滤池,可以使池内水温稳定在22℃左右,设备正常运行。在试验运行开始的第20 d,对SS和BOD5的去除率均达到90%以上,对CODCr的去除率达到85%以上,对NH_3-N的去除率达到90%以上。由此可以说明,两级曝气生物滤池在运行到第20 d时挂膜启动成功。     

ABR工艺处理生活污水研究

本文对折流挡板厌氧反应器处理生活污水进行了研究。反应器沿流向分为三格,实验温度为25℃,水力停留时间12小时,pH在7~7.6。实验结果表明:COD的去除率可维持在70%左右,产气主要含有甲烷、二氧化碳和氢气,每格最大产甲烷活性依次为211 mLCH4.gVSS-1d-1,314 mLCH4.gVSS-1d-1,319 mLCH4.gVSS-1d-1;出水产物为乙酸和丙酸;每格优势菌种依次为杆菌、球菌、甲烷丝状菌和甲烷八叠球菌。填料挂膜量(湿重)沿着流向逐渐降低,平均为4.27 g.cm-3。     

接触氧化-人工湿地系统处理造纸废水的工程应用

对接触氧化 潜流式人工湿地系统处理废纸造纸废水的运行情况进行了分析.结果表明,在进水pH为6.95～8.00,COD Cr 、BOD 5 和SS的浓度分别为1 640 mg/L、568 mg/L、332 mg/L的条件下,COD Cr ,、BOD 5 和SS的去除率分别为95.7%、97.0%和92.8%,系统运行稳定,出水水质达到排放标准且可用于农灌.经济效益和环境效益良好.     

混凝工艺去除鸡粪厌氧消化液有机物及条件优化研究

文章介绍了混凝法去除鸡粪厌氧消化液出水有机物质的工艺及条件优化的研究。在实验室条件下,通过CODcr,SS的去除率评价混凝工艺效果。实验首先进行混凝剂以及助凝剂的筛选,然后进一步考察了特定混凝剂以及助凝剂的优化反应条件。试验结果表明:1.相对于其他混凝剂以及助凝剂,聚合氯化铝(PAC)以及阳离子聚丙烯酰胺(CPAM)是比较优化的组合;2.水力条件是影响混凝效果的关键因素,最佳搅拌速度为250~300 r.min-1左右;3.用Ca(OH)2调节pH值为8.6,PAC投加量为2.0~2.5 g.L-1,CPAM投加量为40~50 mg.L-1时效果较优,去除率分别为82.9%与94.78%。因此,混凝沉淀法能有效去除鸡粪厌氧消化液中的CODcr和SS,有效降低后续处理压力。     

厌氧颗粒污泥膨胀床(EGSB)反应器处理生活污水中试研究

采用规模为240 m3.d-1的厌氧颗粒污泥膨胀床(EGSB)反应器对生活污水进行研究。试验结果表明:采用此系统处理生活污水,出水水质良好。COD的去除率在73%~90%之间,出水的COD值小于70 mg.L-1,SS的去除率在70%~95%之间,停留时间为2 h的产气率在1.26 m3.m-3d-1,出水的氨氮、乙酸值比进水的高;硝酸根离子出水值比进水值低。     

折板式厌氧滤池反应器高温处理酒精糟液研究

利用ABFR反应器在高温(53～55 ℃)下处理酒精糟液高浓度有机废水,经过120天的试验,结果表明容积负荷高达39.6 g COD·L-1d-1时,COD去除率维持在85%以上,SS去除率维持在99%以上,产气率为0.32 L CH4·gCOD-1;生物膜可去除90%以上的COD和75%以上的SS;反应器前四个区域可去除94%的COD.     

洗浴废水处理及回用实例

介绍了采用混凝+活性炭吸附工艺处理某矿洗浴废水并回用的设计及调试运行实例。结果表明,在进水CODCr为73 mg/L,BOD5为36 mg/L,SS为82 mg/L,色度为45度,浊度为15度时,出水中CODCr为25 mg/L,BOD5为7 mg/L,SS为3 mg/L,色度为10度,浊度为4度,对CODCr、BOD5、SS、色度、浊度的去除率可分别达到65.8%、80.6%、96.3%、77.8%、73.3%,该工艺运行稳定,出水水质达到《生活杂用水水质标准》(CJ25.1-89)规定水质标准。该工程的稳定运行不仅减轻了该矿澡堂废水的污染且有效地解决了该矿生产用水紧张的问题。     

分散式无动力生活污水处理装置处理效果分析

分散式无动力生活污水处理系统是我国农村生活污水处理的一个重要的组成部分,笔者在四川省乐至县选取了两种不同的无动力生活污水处理设施,对其处理效果进行了检测,检测数据表明:1)无动力生活污水净化装置对COD和SS去除明显,平均去除率可达到60%以上,出水COD多在100 mg·L~(-1)以下,SS在40 mg·L~(-1)以下;2)单独的生活污水净化池对于氨氮和磷的去除率都在10%以下,有时出水氨氮和磷会略高于进水;3)生活污水净化池+人工湿地的处理系统对于氨氮和磷的去除率较单独的生活污水净化池略有提高,5~6月份的去除率高于1~2月份去除率。     

Overland water and salt flows in a set of rice paddies

Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m⁻¹) and an infiltration rate of 5.8 mm day⁻¹. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day⁻¹), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day⁻¹ was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration.     

瓦房店市水果生产标准化发展研究

瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。     

金谷子耐旱TG118引种试种及推广应用

对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。     

对《种子法》存在问题的探讨

《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。     

Review of the Egyptian experience in implementing land drainage projects

About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered.     

和谐社会理论建设的几点哲学思考

在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。     

A European irrigation map for spatially distributed agricultural modelling

We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications.     

粉质仪和拉伸仪在面粉生产中的应用

在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。     

农村信息化服务的现状及建设措施

分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。     

车辆ABS控制算法的研究及探讨

对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。