秸秆成型燃料炉具设计与试验

以作物秸秆为原料制成的生物质颗粒燃料具有便于储存运输,燃烧热效率高等优点,可以用来替代煤炭作为农村家庭生活炊事与冬季取暖的主要能源。但生物质颗粒燃烧会排放较多的氮氧化物,目前生物质脱氮一般应用于大型工业炉内,农村家用的生物质锅炉基本没有氮氧化物处理装置。根据生物质燃料的燃烧特性,本文首先阐述了所设计秸秆成型燃料专用炉具的结构和关键燃烧技术,对玉米秸秆成型燃料进行燃烧试验研究。采用KM9106型烟气分析仪测量燃烧时烟气中NO、NO2和烟气氧含量。结果表明通过改变二次风的风量比例、进气位置、充气角度,在炉具内形成不同的风压射流,以强化热质传递,确保燃尽效果,有效控制氮氧化物的生成与排放。试验结果表明,当一、二次风量比例为3∶1、扰流形成的风压射流配送二次风时,秸秆成型燃料烧温度最高,燃烧充分,满足高效清洁燃烧要求。     

新型多用生物质炊事取暖炉

生物质炊事取暖炉是高效、环保、节能的半气化炉,采用生物质作为燃料,燃料在炉膛内气化产生可燃气体,可燃气体在二次供氧状态下再次燃烧,实现生物质的充分燃烧,达到提高炉具热效率的效果;同时,减少烟尘排放。本炉具的核心技术为实用新型专利《彝家锅桩炉具》(专利号为ZL201120488433.8),通过半气化方式燃烧,能提高热效率和燃尽率,烟尘通过     

生物质混燃在农村能源供应中应用分析

通过对比生物质、燃煤及两者1∶1的混合燃料在燃煤炉具中采暖及炊事两种工况下的能量效率、排放特征及经济性能,具体量化生物质混燃的技术优势,为清洁低廉的生物质能在农村地区的推广提供理论依据。结果显示,在燃煤炉具中混合燃料燃烧时的能源效率明显高于生物质燃料,且其采暖工况效率高于炊事工况效率近20%。相比于燃煤,混燃时主要气态污染物SO2、NO、NO2综合减排效果良好,PM2.5排放量远低于国标限值（100mg/MJ）。其主要有机污染排放PAHs也能得到有效控制,尤其是高环PAHs在采暖和炊事工况下的减排率可分别达到34%和87%。而相比于生物质,混燃时CO排放较少,在采暖工况下减排率为46%,炊事工况则为61%。此外由于人为操作较少,采暖工况下的污染排放量较为稳定。混合燃料价格较低,单位能量价格为0.039元/MJ,而单位质量价格仅为燃煤的1/2,燃烧器可使用低成本燃煤炉具,避免使用价格昂贵的生物质专用炉具,可确保低收入家庭居民日常用能支出维持在经济承受能力范围之内。     

生物质颗粒燃烧器的设计与性能测试

针对生物质颗粒燃烧器燃烧不充分及燃烧效率低等问题,设计了一款小型生物质颗粒燃烧器。该燃烧器换热量为0.5 t/h,进料量为20kg/h,并采用三次配风系统,设置7个配风口。本研究对小麦、玉米、水稻3种作物的秸秆制成的生物质颗粒燃料进行了锅炉换热试验。试验结果表明:小型生物质颗粒燃烧器采用的三级配风系统配风均匀分布,满足燃料的充分燃烧;3种颗粒燃料燃烧效率均在95%以上,最终的结渣率均不超过5%,燃烧产物达到环保标准。该设计为生物质颗粒燃烧器的应用与推广提供了理论依据。     

生物质颗粒直燃炉灶设计与试验

针对当前生物质燃烧炉灶热效率低、火力强度达不到要求、供风不充足燃烧不完全、功能单一等问题,依据集中供餐炊事对清洁生物质颗粒燃料炉灶的需求,研制了一种以层燃为燃烧方式,集炒菜、蒸饭、烧水、供热等功能于一体的生物质颗粒直燃炉灶。运行性能试验结果表明:该炉灶的炊事热效率为42.9%,综合热效率达70.7%,炊事强度为14.1 k W,烟气排放指标低于国家标准,生物质颗粒燃烧较为充分,可为以生物质颗粒为燃料的集中供餐炊事炉灶的设计与应用提供科学参考。     

生物质成型燃料锅炉燃烧控制系统设计与试验研究

为实现生物质成型燃料锅炉高效清洁燃烧的目标,通过对生物质成型燃料燃烧过程进行多变量耦合特性分析,提出基于前馈串级复合控制方法的生物质成型燃料锅炉燃烧控制方案,并对搭载该燃烧控制系统的生物质成型燃料锅炉进行热平衡试验和大气污染物排放浓度检测试验。试验结果表明:当过剩空气系数α为1.7时,燃烧效率最高,达到83.2%~83.7%,且各项污染物排放浓度均低于国家排放标准要求,具有较高的推广利用价值。     

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。     

一种生物质燃料多功能一体炉具的设计

针对目前生物质燃料炉具多数存在热效率不高、烟气氮氧化物含量高、使用不方便、功能单一等问题,提出一种生物质燃料多功能一体炉具设计方案,有自动点火、自动供料、炊事灶体、两次配风装置、水箱体、安全装置、通炕接口等设计,主要用于村镇居民炊事、冬季采暖、烧炕等.     

基于最小二乘曲线拟合法的生物质压块质量与热效率关系研究

研究某锅炉燃烧热效率与燃烧生物质压块质量的关系,通过采用最小二乘法拟合温升与生物质压块质量的函数曲线,并且利用数据分析验证得出最优拟合曲线。同时,利用热效率计算方法计算各燃烧生物质压块质量对应的热效率,最终得出热效率随生物质燃料质量变化规律,为锅炉使用标准提供参考依据。     

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。      

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。