屠宰废水厌氧滤器沼气发酵研究

肉类加工厂屠宰废水(COD值为1000—2500mg/l)采用厌氧滤器沼气发酵处理,在33℃下,在单一滤柱的滤器中废水滞留0.5天,产气率达到1101ml/l和296ml/gCOD,废水COD去除率为81％。在单柱滤器中滞留1.16天,或在双柱串联滤器中滞留1.05天,产气率分别为691ml/l/天、491ml/gCOD和639ml/l/天、355ml/gCOD,COD去除率分别达87％和91％。     

初始pH值对微波预处理颗粒污泥厌氧发酵制氢的影响

以高浓度有机废水为发酵底物,接种颗粒污泥进行厌氧发酵制氢,通过批量试验研究了初始pH值对经微波预处理后的颗粒污泥厌氧发酵产氢的影响.结果表明:初始pH为9.0时,产氢效果最好,此时的比产氢速率达到24.23 mmolH2·(gCOD·d)-1,COD去除率约为31％,出水挥发性脂肪酸浓度为3768 mg·L-1.     

两步厌氧发酵工艺处理浓缩胶乳加工废水的生产性研究

用两步厌氧发酵工艺处理浓缩胶乳加工废水的生产性研究结果表明，这种含有高浓度硫酸盐和氨态氮的酸性废水，在常温条件下，发酵池有机负荷率为１．５７ｋｇＣＯＤ／（ｍ￣３·ｄ），容积产气率达０．６０ｍ￣３／（ｍ￣３·ｄ），ＣＯＤ去除率为７０．３％。每处理１ｍ￣３废水（ＣＯＤ值２５０００ｍｇ／Ｌ）可生产含甲烷６０％以上的沼气８．２ｍ￣３，应用于胶清胶的干燥，可节省干燥所需鱼油的８５～９０％。废水厌氧发酵后经氧化塘进一步好氧处理，出水ＣＯＤ值１６６ｍｇ／Ｌ，ＮＨ＿３－Ｎ　６９ｍｇ／Ｌ，Ｓ￣（２－）３．９ｍｇ／Ｌ。大大减轻了废水对环境的污染，为浓缩胶乳加工废水提供了一种节能的处理方法。     

宁波大型餐厨垃圾厌氧发酵装置简介

针对餐厨垃圾处理过程中产生大量高浓度有机废水的现状,将该废水进行厌氧发酵,去除有机物同时回收生物质能(沼气)并加以应用.文章以宁波市某沼气工程为例介绍了餐厨垃圾废水通过厌氧发酵生产沼气的工艺技术.该工程废水pH 3.5～4.0,CODcr80～120 g·L-1,处理量为110 t·d-1,控制厌氧发酵温度为(35±3)℃,每去除1 kgCODcr,可产沼气0.6～0.7m3,产气率为3.0～4.0 m3·m-3d-1,CODcr去除率达到91%以上,年可产沼气260万m3,可发电450万kWh.     

多段折流板厌氧反应器处理高悬浮固体有机废水的研究

本文报道了耐高悬浮固体(SS)的多段折流板厌氧反应器处理全酒糟废液的试验。试验结果表明,在53—55℃.进水 SS21g/L,水力停留时间(HRT)8hr,系统能稳定运行,SS 沉降去除率达99%,反应器 COD 容积负荷可达110gCOD/L·d,COD 去除率达85%左右,甲烷产率为0.321LCH_4(STP)/去除 gCOD。     

蒸汽爆破预处理玉米秸秆厌氧发酵实验研究

2.0 Mpa压力下,保留时间60 s,90s和120 s对玉米秸秆汽爆预处理后进行厌氧发酵生产沼气实验,研究汽爆预处理秸秆厌氧发酵规律,探讨提高秸秆厌氧发酵产气量的新工艺.结果表明:蒸汽爆破预处理后的秸秆比未经预处理秸秆中温厌氧发酵的产气量296.8 mL·g-1提高16.8％～63.2％,保压时间为120 s时,秸秆厌氧发酵沼气产量达到最大值428.5 mL·g-1干物质.汽爆处理玉米秸秆厌氧发酵沼气中CH4含量在60％以上,发酵第20d累积产气量达到总产气量的80％,未发生结壳现象,主发酵周期比未汽爆秸秆大大缩短.     

标准胶加工废水加水葫芦厌氧处理的研究

本文对标准胶加工废水和氧化塘种植的水葫芦厌氧发酵制取沼气进行了研究。结果表明,水葫芦是一种良好的沼气发酵原料,批量发酵每克干物质可生产沼气０．３４４Ｌ。常温下,水葫芦预发酵后与废水按１：３比例混合连续发酵,混合液每克ＣＯＤ可生产沼气０．５５６Ｌ,容积产气率达１．７８Ｌ／（ｌ．ｄ）。为氧化塘种植的水葫芦提供了一个有效的处理方法。     

管道厌氧消化工艺处理柠檬酸废水试生产性研究

本文在简要介绍管道厌氧消化工艺反应装置的有关性能的基础上,主要报道容积45m~3的试生产性装置处理杭州柠檬酸厂废水的结果。管道厌氧消化器由若干管节横向串联组成,其水力运行呈推流式,能够持留高浓度的活性污泥,具有两步厌氟消化性能。中温下试生产性平均处理浓度20gCOD/1的柠檬酸废水,取得了明显的综合效益。按有效容积计的有机质负荷为15.50kgCOD/m~3·d,COD去除率84％,容积COD去除率13.4kg/m~3·d,产沼气率为7.5m~3/m~3·d。     

菌种添加量对生物预处理小麦秸秆厌氧发酵的影响

对小麦秸秆进行了氨-生物联合预处理,在实验室自制的小型厌氧发酵装置上,对预处理后的小麦秸秆进行了厌氧发酵制取沼气试验,探讨了氨-生物联合预处理中,菌种的添加量对小麦秸秆厌氧发酵产沼气的影响.结果表明,在氨预处理尿素溶液质量浓度为35 g/L,生物预处理pH值为4,黄孢原毛平革菌和里氏木霉的添加比例为1∶1(数量级为109)的条件下,小麦秸秆厌氧发酵过程中沼气总产气量最大,为7 968 mL,较空白组提高了23.11％.发酵过程终了pH值、VFA和甲烷的变化均在正常的范围内,甲烷最高体积分数为51.33％,较空白组提高了6.01％,整个发酵过程历时23 d.     

连续干式厌氧发酵中试系统设计与试验

设计了以卧式浆叶轴机械搅拌厌氧发酵罐为核心的干式发酵技术与成套装备.利用该技术建成干式厌氧发酵中试工程.工程包括预处理及进料系统、厌氧发酵系统、沼气净化与贮存、增温保温系统、出料系统等.工艺方案中克服了干式厌氧发酵进出料困难、传质传热不均的难题,实现了连续高温干式厌氧发酵产沼气.中试结果表明,系统运行稳定,产气效果较好,平均有效容积产气率达3.0 m3/(m3·d).     

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。