国电山东电力有限公司启动污染物近零排放示范改造

<正>日前,国电山东电力有限公司启动烟气污染物近零排放示范改造工作,最大限度减少对环境的污染,更好地履行国有企业环境质量和公众健康的社会责任。该公司烟气污染物近零排放示范改造是在已满足山东省新的地方排放标准的条件下,采用高效协同脱除技术,对脱硝、脱硫、除尘系统进一步提效改造,使机组烟气的主要污染物排放浓度达到天然气机组的排放标准。改造后烟囱出口氮氧化物排放浓度不大于     

循环流化床锅炉的烟气处理分析

本文介绍了循环流化床锅炉SO_2和NO_x的形成机理,提出降低SO_2和NO_x排放浓度的脱硫脱硝的方法,并根据化工企业循环流化床锅炉废气处理的不断实验,得出控制SO_2和NO_x排放的措施,可以有效改进循环流化床的生产运行,为化工企业环保达标提供有效手段。     

基于Thiobacillus thioparus菌株的生物脱硫工艺参数优化研究

文章研究采用生物脱硫工艺利用生物滴滤池,以异养脱硫菌Thiobacillus thioparus为菌株,分别研究了以陶粒、火山岩、活性炭为滴滤池滤料条件下溶解氧,硫化物负荷,气液体积比,pH值等生物脱硫工艺参数对H_2S去除效果的影响。实验结果表明:溶解氧影响Thiobacillus thioparus菌株对硫化物的去除率,通过单因素实验发现,当硫化物负荷为80 g·m~(-3)h~(-1),DO为1.5 mg·L~(-1)时,硫化物去除率达80%以上,单质硫回收率最大;硫化物负荷对H_2S去除有影响并且与DO呈线性关系;循环液pH值为8.5时,沼气中S~(2-)去除率达94.3%,此时单质硫转化率大于SO_4~(2-)的转化率;当沼气中H_2S浓度为4200±14 mg·m~(-3)、气液比为15∶1时,硫化物去除率达93.9%。在不同反应条件下,利用3种滤料填充滴滤池,其中活性炭的去除效果均优于其他两种滤料,陶粒和火山岩效果差别不大。     

防回火农林生物质碎料燃烧机设计与燃烧特性试验

针对农林生物质碎料在燃烧时存在连续进料及稳定燃烧困难、污染排放水平较高等问题,设计一种以玉米秸秆、碎木屑为主要燃料的农林生物质碎料燃烧机,采用水平进料方式,并进行防回火回烟、炉壁冷风压保护等设计,在不同一、二次风配比下进行了燃烧特性试验。当燃烧机进入稳定燃烧阶段,以碎木屑为燃料,一、二次风配比为0.8∶0.2时,炉膛内温度在(1 200±100)℃间变化,出火口烟气温度在(1 000±100)℃间变化;在一、二次风配比为0.8∶0.2和0.7∶0.3两种工况下,烟气中O_2、CO_2、CO质量分数分别在(13±2)%、(7±2)%、(0.2±0.1)%间波动,燃烧效率分别为98.8%、98.5%。以玉米秸秆为燃料时,在相同一、二次风配比下,与燃烧碎木屑相比,炉膛内温度和出火口烟气温度均低100℃左右;在一、二次风配比为0.8∶0.2和0.7∶0.3两种工况下,与燃烧碎木屑相比,燃烧烟气中O_2平均含量约低1%,CO含量略高,CO_2含量相差不大,燃烧效率分别为98.7%、98.9%。与一、二次风配比为0.8∶0.2相比,当一、二次风配比为0.7∶0.3时,以碎木屑或玉米秸秆为燃料时的炉内温度、出火口温度均低100℃左右。经JCP-HD型林格曼黑度计观测,以玉米秸秆或碎木屑为燃料,在一、二次风配比为0.8∶0.2和0.7∶0.3时排放的烟气林格曼黑度小于等于1级。当一、二次风配比为0.8∶0.2时,以碎木屑为燃料,烟气中PM2.5、PM5、PM10变化范围分别为56～72 mg/m~3、38～51 mg/m~3、43～63 mg/m~3,以玉米秸秆为燃料,分别为36～43 mg/m~3、21～35 mg/m~3、38～42 mg/m~3,满足锅炉大气污染物排放标准要求。     

管式GGH烟气换热器概述及现场安装流程分析

管式GGH是近年来燃煤机组超低排放改造的主要设备,主要作用是用于加热经过脱硫、湿法除尘后的低温、水分饱和的烟气(净烟气)至规定温度的装置,热源来自脱硫处理前的烟气,从而提高系统效率,改善烟囱出口"冒白烟"以及"石膏雨"等现象。本文论述了管式GGH的主要工作原理、技术路线、系统结构,分析了管式GGH在现场安装的工艺流程。     

水泵厂冲天炉颗粒层除尘试验研究

介绍了水泵厂冲天炉LXK型颗粒层除尘系统的试验研究成果。在冲天炉的熔炼过程中，除尘器能经受高温烟气的热冲击，除尘性能稳定．效率达98.6％，排放浓度平均为168mg／m3。     

生物质燃烧烟气排放特性与污染物控制

生物质锅炉及颗粒燃烧器的烟气污染物排放已引起人们的重视。生物质燃烧产生的污染物主要有颗粒物、一氧化碳和氮氧化物等污染气体。综述了国内外关于生物质燃烧的烟气排放特性及影响因素,如不同生物质燃料种类及性能、进风系统和进料系统配置及参数等,着重介绍了进风系统中风量配比、过量空气系数、氧气浓度以及进气流速等因素对烟气污染物排放的影响,提出了生物质燃烧烟气排放特性和污染物控制研究中应注意的问题。      

曝气生物滤池系统处理含氨氮废水的试验研究

为了进一步研究曝气生物滤池工艺在污水处理中的应用,采用曝气生物滤池处理工艺,对氨氮质量浓度较高、其他污染物量较低的废水进行了工艺运行条件及处理特征的模拟试验,主要研究了气水比、水力负荷、氨氮负荷等因素对氨态氮等污染物处理效果的影响。结果表明,进水氨态氮质量浓度约为25 mg/L时,气水比为3∶1和4∶1时,曝气生物滤池系统出水氨态氮质量浓度均低于7 mg/L;系统出水COD平均质量浓度随气水比增大而升高;在气水比为2∶1,进水氨态氮质量浓度相近条件下,水力负荷调整为5 m~3/(m~2·h)时,系统出水氨态氮质量浓度低于12 mg/L,去除率达到54%。     

垃圾与煤、秸秆混燃锅炉污染物排放优化

依据山西省某垃圾混燃电厂现场运行数据,建立了垃圾与煤、秸秆混燃锅炉污染物排放过程模型,验证表明模型能够较好地模拟混燃锅炉污染物排放过程。拟合了混燃过程烟气污染物排放多目标优化函数,优化计算得到Pareto最优解集。依据混燃温度在850～900℃时二噁英可被有效分解的工程条件,进一步从Pareto最优解集中选取了污染物排放值能够满足工程要求的锅炉混燃运行工况有效解子集,该子集表明当温度大于850℃时,随煤掺混量适当增加及温度升高,锅炉侧出口二噁英排放值已显著降低,最小值达0.012 8 ngTEQ/m3,远优于烟气最终允许排放国家标准值1.0 ngTEQ/m3及现场烟气经净化处理后测试值0.026 ngTEQ/m3,且其他污染物排放值也远低于现场锅炉侧出口实际测试值。     

吸收式热泵对生物质直燃烟气余能利用的影响研究

针对生物质热电联产系统烟气直接排放造成的能源浪费等问题,本文提出一种利用吸收式热泵梯级回收烟气余热的系统,分析了生物质直燃锅炉的■平衡,利用Aspen Plus软件模拟了烟气余热回收系统,并基于模拟数据进行■分析和节能环保效益分析。结果表明:生物质直燃锅炉的■效率为40.36%;烟气余热回收系统的■效率达32.89%,■损失主要分布在排烟损失;相比于未回收排烟余热的生物质直燃热电联产系统,加入烟气余热驱动的吸收式热泵辅助供暖后,系统的烟气余热回收利用率、节能率和综合能源利用率分别提升了11.06%、4.79%和6.70%;每个采暖季供热量可折合标煤2088.56 t,相应地可减排CO_2、SO_2、NO_X和碳粉尘分别为5 206.78 t、17.75 t、15.66 t和1 402.22 t。因此,利用吸收式热泵回收生物质直燃烟气余热具有可观的节能环保效益。     

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。