短程硝化液提升市政污泥中温厌氧消化产沼能力的工程试验分析

文章通过控制桂平市污泥处理厂中沼液多级好氧生化系统的曝气量,获得含游离亚硝酸(FNA)的短程硝化液并回流至有效容积为100 m3的中温厌氧反应器,与市政剩余污泥进行联合厌氧消化产沼气.试验结果表明:短程硝化液的加入可显著提高市政污泥中温厌氧消化产酸产气效率.当反应器中HNO2-N浓度为178 mg·L-1时,SCOD的...     

绿化废弃物与污水污泥混合比对污水污泥厌氧消化性能的影响

文章以污水处理厂污水污泥和干湿绿化废弃物(Gd,Gw)为研究对象,采用中温(35℃)共厌氧消化的方法,研究了干湿绿化废弃物与污水污泥(S)VS混合比分别为1∶2,1∶3时,与单纯污水污泥厌氧消化相比,在产甲烷量和溶解性有机物转化率上的差异,明确添加绿化废弃物对污水污泥厌氧消化性能的影响。研究结果表明,在相同VS条件下,绿化废弃物与污水污泥混合体系的甲烷产量与有机物转化率均明显高于单纯污水污泥体系;不同混合比对绿化废弃物和污水污泥共厌氧消化的甲烷产量有明显影响,且相同VS混合比的湿绿化废弃物较干绿化废弃物产甲烷量高;湿绿化废弃物与污水污泥VS混合比为1∶2时,混合体系单位VS累积产甲烷量最高,达291.58m L·g-1VS,较污泥单独厌氧消化提高了14.29%,较相同VS混合比干绿化废弃物提高了6.27%;最优产气工况Gw∶S为1∶2时,SCOD和溶解性碳水化合物、溶解性蛋白质和VS的转化率较污泥单独厌氧消化分别提高了2.28%,10.22%,16.89%和14.70%。由于添加绿化废弃物后,混合体系相比单独污水污泥系统,提高了有机物转化效率,是其产甲烷量较高的根本原因。     

金属离子对剩余污泥和生活垃圾联合厌氧消化的影响

以城市有机生活垃圾和污水处理厂剩余污泥作为发酵原料,在相同条件下,研究不同浓度的Fe2+,Co2+,Ni2+组合对厌氧消化过程和消化效率的影响。结果表明,添加金属离子能提高垃圾的消化效率,当Fe2+,Co2+,Ni2+的浓度分别为3 mg·L-1,1.5 mg·L-1,1.5 mg·L-1时厌氧消化效果最好,COD降解率为71.14%,TS去除率为48.83%,VS去除率为69.34%,与对照相比分别提高了13.79%,17.09%,15.54%。     

膜浓缩污泥厌氧消化性能的研究

城市污水通过膜浓缩是一种截留有机物及减少能耗的有效方式。BMP实验研究了在膜池停留时间(SRT)为6 d、4 d、2 d的膜浓缩污泥含水率分别为96%、94%、92%时的厌氧消化性能。结果表明：膜浓缩污泥的总产甲烷量随含水率的降低而升高。单位VS产甲烷量随含水率的降低先升高后降低，含水率为94%时最高，为167.6 mL·g^-1VS～205.3 mL·g^-1VS,比初沉污泥(155.7 mL·g^-1VS)提高了7.6%～31.8%;比剩余污泥(159.1 mL·g^-1VS)提高了5.3%～29.0%;COD降解率(36.6%～48.7%)比初沉污泥(33.2%)、剩余污泥(29.6%)分别提高了10.2%～46.7%、23.6%～64.5%。同一SRT工况下的污泥，蛋白质去除率随着含水率的降低呈现增加的趋势，而多糖类碳水化合物去除率相反，呈现下降的趋势。膜浓缩工艺促进了蛋白质、多糖类碳水化合物等有机物的溶出降解，从而提高厌氧消化产甲烷潜能，为城市污水处理厂实现“能源中和”提供可能。     

奶牛养殖污水厌氧消化液好氧后处理的试验研究

文章采用批式厌氧消化试验加试验模拟序批式活性污泥法(SBR)工艺处理奶牛场养殖污水。研究了该组合模式对奶牛场养殖污水的处理效果,同时讨论了对化学需氧量(COD),NH4+-N,总氮(TN)和总磷(TP)去除原因。厌氧消化停留时间分别为3,6,9,12,15,18 d;试验模拟SBR工艺周期为12 h。试验表明在厌氧消化9 d时,COD和BOD5的去除率分别为82.1%和96.9%,接近最大去除潜力,剩余的主要为难降解COD。在试验模拟SBR活性污泥条件下,好氧段对于厌氧消化时间在0～9 d内的厌氧消化液的NH4+-N去除效果比较好,最高可以达到97%。厌氧-好氧组合除氮除磷的效果是较理想的,去除率均达到近90%。在厌氧消化3～9 d内,好氧段12 h,能够将奶牛场养殖污水原水的TN含量从731 mg.L-1降解到99 mg.L-1,TP含量从66 mg.L-1降解到7 mg.L-1。如果厌氧消化时间过长,超过9 d,厌氧消化液碳氮比值很低,对厌氧消化液好氧后处理带来不利影响。研究结果为进一步优化养殖污水沼气工程处理提供了一定的参考价值。     

城市污水处理厂污泥沼气资源化利用

本文叙述了污泥厌氧消化沼气利用的运行管理与注意事项,介绍了污泥厌氧消化采用超声波和臭氧的预处理技术,以及利用厌氧消化所产沼气进行发电的技术应用.提出了厌氧消化利用沼气是实现城市污水处理厂污泥减量化、稳定化、无害化和资源化的有效手段,具有广阔的发展前景.     

污水处理厂污泥堆肥化处理研究

以深圳市滨河污水处理厂污泥为研究对象,采用干污泥和回流污泥为调理剂,以树叶粉和木屑调节碳氮比,用强制通风静态发酵装置对污泥进行堆肥化处理,探讨污泥堆肥的工艺条件.研究结果表明,采用湿污泥与干污泥或回流污泥体积比1:1混合可以满足污泥堆肥水分调节的目的,用树叶粉和木屑调节碳氮比有利于污泥堆肥的进行,但会增加污泥堆肥的成本.不同处理污泥堆肥堆体的温度在55℃以上维持时间都超过了12d,达到了污泥无害化与稳定化的标准.通过中试规模的装置对以干污泥或回流污泥作为调理剂的污泥堆肥研究表明,湿污泥与干污泥体积比1:1有利于污泥的无害化与稳定化.     

《中国沼气》2005年（第23卷）总目录

.与实验研究.活性污泥法污水厂剩余污泥微氧消化的试验研究……………………胡颖华,孙丰霞,高廷耀,等1-3缺氧生物滤池处理城市污水微生物特性研究……………………………方芳,龙腾锐,郭劲松,等1-7ABR反应器中颗粒污泥的微生态特性………沈耀良1-13沼气脱硫技术研究新进展………     

城市生活垃圾特性及其厌氧消化产甲烷潜能研究

文章以城市生活垃圾为原料,对比分析城市生活垃圾快速好氧发酵预处理前后理化特性的变化,并通过批式厌氧消化实验对预处理前后的厌氧消化产甲烷潜能进行了对比研究。结果表明,经过快速好氧发酵预处理,城市生活垃圾pH值升至7.86,C/N下降至30~35,碱度出现明显增加,易降解有机物部分降解,难降解有机物的百分含量增加。厌氧消化阶段,未处理和预处理城市生活垃圾中有机物单位VS累积产甲烷量分别为265.0~301.6 mL·g-1VS和308.3~358.4 mL·g-1VS,预处理垃圾单位VS累积产甲烷量比未处理高16.34%~18.83%;未处理和预处理城市生活垃圾中有机物VS去除率分别为75.87%~81.19%和81.28%~88.00%,预处理垃圾VS去除率比未处理高5.41%~6.81%。     

一种适合农村的污水处理技术-厌氧折流板反应器

在经济技术水平欠发达的农村,寻找可行的废水处理解决方案是一项挑战。城市好氧污水处理厂的建设,运营和维护成本高,并不适合农村。厌氧折流板反应器(ABR)具有结构简单、易于制造、固体生物截留能力强、污泥产量低、抗冲击负荷能力高、对有机物处理效果好、运行成本低等特点,非常适合农村分散污水处理。介绍了ABR反应器的发展与改进,综述了温度、pH、进水有机物浓度、水力停留时间、反应器启动、冲击负荷等因素对ABR处理效果的影响,分析了ABR反应器适宜的污水浓度范围以及在农村应用的可行性,介绍了基于ABR的组合工艺。     

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。