外源添加物对抗结壳沼气反应器产气特性影响

针对沼气反应器发酵原料利用率低、发酵周期长、产气率低等问题,实验研究尿素、复合磷酸盐及复合维生素等外源添加物对以马铃薯皮为发酵原料的新型抗结壳沼气反应器产气性能的影响。结果表明:一定浓度的外源添加物能缩短抗结壳沼气反应器的发酵启动时间,促进甲烷合成,显著提高反应器的日产气量。在最佳尿素添加量为1.0g/L时,总产气量提高52.9%,池容产气率为0.869m3/(m3.d),发酵后期甲烷浓度稳定在约65%;复合磷酸盐最佳添加量为1.200g/L时,此时总产气量提高28.9%,池容产气率为0.659m3/(m3.d),发酵后期甲烷浓度稳定在约68%;复合维生素最佳添加量为0.015g/L时,其总产气量提高48.4%,池容产气率为0.843m3/(m3.d),发酵后期甲烷浓度稳定在约70%。     

组合碱预处理对玉米秸秆厌氧消化的影响

为提高玉米秸秆厌氧消化的产气量及产气效率,采用不同质量分数的组合碱(质量比为2∶1的NaOH和Ca(OH)2)对其进行预处理,经过3 d的预处理后,考察组合碱对玉米秸秆成分及厌氧消化产沼气的影响。结果表明,组合碱预处理能有效缩短消化启动时间,并不同程度提高秸秆的产沼气能力。其中质量分数为3%的组合碱处理组产气状况最好,消化60 d后的总产气量可达24035 m L,日均产气率为400.58 m L/d,总固体产气率、挥发性固体产气率分别为358.73 m L/g和369.77 m L/g,在相应的厌氧消化时间内有效提高了玉米秸秆的厌氧消化效率。     

华南地区稻草的厌氧干发酵制取沼气研究

研究了经过C/N调节和白腐菌预处理后的稻草在不同温度条件下的干发酵瓶试实验,并根据瓶试实验结果以及华南地区的气候条件,进行了常温1m3罐试实验.瓶试实验结果表明在35℃条件下秸秆干发酵较为稳定,具有较高的产气率、产甲烷率及沼气质量.1m3罐试实验在常温条件下运行89d,累积产气量22.6m3,且前45d的累积产气量约占总产气量的80.4%.发酵原料产气率为570L/kgVS,产甲烷率为240L/kgVS,甲烷百分含量最高可达62%.从pH值、产气量和甲烷百分含量来看,整个发酵过程均为正常发酵.通过循环发酵液的罐试实验表明,发酵液的循环能有效避免酸中毒并提高产气率和产甲烷率,对稻草干发酵而言,循环发酵液是一种较好的搅拌方式.该工艺可为华南地区稻草秸秆的资源化利用提供依据.     

醋糟厌氧发酵特性的研究

以醋糟为厌氧发酵原料,分别进行了连续进料试验和全进全出料试验。连续进料试验结果表明,在每天进料量保持不变的情况下,日产气量稳定,平均产气率为0.918 m3/(m3.d),最高产气率可达1.111 m3/(m3.d)。经过计算可知,8.52 kg醋糟可产1 m3沼气。全进全出料发酵试验结果表明,醋糟厌氧发酵的体积上浮和膨胀非常明显。当进料浓度为4%时,料液最大膨胀体积为322.68 cm3,为发酵料液体积的28.8%。醋糟厌氧发酵具有降解速率快,滞留期短等特点。     

基于中温两相厌氧发酵技术的不同配比牛猪粪对寒地户用沼气的影响

设计一种位于日光温室内并采用中温两相厌氧发酵装置,在前期单一牛粪为发酵原料的基础上,在其中加入一定量的猪粪,探讨所设计的新型农村户用沼气发酵装置产气量与维持发酵罐体内料液温度所消耗沼气量之间的关系。结果表明:当牛粪与猪粪混合液总固体含量为1∶1时,该沼气发酵装置最高池容产气率为1.5L/(L.d),比单一牛粪为原料的池容产气率(1.35L/(L.d))高,是传统沼气池产气率(0.35L/(L.d))的4倍多。日均结余沼气量为7.85m3,足以满足三口之家照明、炊事所需能源,实现高寒地区户用沼气全年正能输出,而且装置结构设计合理,设备完善,可取代传统沼气池。     

有机负荷对厨垃圾厌氧消化系统稳定性的影响

厌氧消化是餐厨垃圾产业化处理的主流方式,酸化是影响餐厨垃圾厌氧消化过程稳定的关键,单位有机负荷是引起酸化的最主要因素.系统研究了不同单位体积有机负荷的产气情况.试验结果表明,在2.5～2.8kg TVS/(m3·d)单位体积有机负荷水平,全混合厌氧消化系统可以获得稳定的高产气率,达到2.55～2.68m3/(m3·d).当单位体积有机负荷进一步提高,系统内挥发性脂肪酸总量、pH值、碱度和沼气中甲烷含量急剧下降,体系迅速转向酸化.     

产甲烷菌固定化新方法及其甲烷化特性

为了克服以PVA为包埋介质对甲烷八叠球菌进行固定化存在的缺点 ,采用吸附和包埋结合法对甲烷八叠球菌进行固定化 ,并用固定化甲烷八叠球菌处理人工废水和豆制品废水 ,对其特性进行研究。用人工废水运行的结果表明 ,最高容积负荷为 14 7kgCOD/m3·d ,最高COD去除率为 94 3 % ,最低水滞留期为 16 4h ,甲烷含量为 65 %～73 %。用豆制品废水运行的结果表明 ,最高COD负荷 17 6kgCOD/m3·d ,平均容积负荷 8 2kgCOD/m3·d,最短水滞留期 13 7h。最高产气率 7L/d·L平均产气率固定化为非固定化的 15 .2倍 ,最高COD去除率达到了 87.0 % ,运行期间固定化介质不上浮、不膨胀 ,具有很好的传质和脱气性能 ,较好的解决了包埋法固定化中存在的问题。     

基于PLC和组态软件构建沼气发酵控制系统

根据沼气干发酵工艺流程和控制要求,提出了基于PLC和组态软件的沼气发酵自动控制系统。该系统能够实现鄂尔多斯示范工程沼气发酵生产过程的实时监控和自动控制。系统能够利用组态软件KingView6.55在沼气发酵系统中完成数据的上传下达、组态的开发、功能的分析、监控画面的建立、计算机与PLC的通讯,实现沼气发酵过程的高产气率和设备的稳定运行。针对鄂尔多斯示范工程中有效容积为300 m3的立式厌氧发酵罐及整套工艺设备进行了调试与运行,结果表明:在该系统自动控制下,21 d后发酵过程达到了稳定状态,沼气日产气量达到360 m3,且沼气中甲烷含量达到56%以上。     

低温纤维素降解菌系对沼气发酵过程中产酸、产气的影响

将本实验室一组稳定的低温兼性厌氧纤维素降解菌系X1接种到水稻秸秆和牛粪混合沼气发酵底物中,研究其在20℃低温沼气发酵过程中对产酸、产气的影响。结果表明,底物降解时主要产生乙酸、丙酸和丁酸,使pH值下降,处理组处理12 d时乙酸、总挥发性脂肪酸及甲烷含量分别为1.22,2.23 g/L和37.50%,对照组分别为0.47,0.81 g/L和28.50%。处理12 d后随着乙酸含量的逐渐下降,甲烷含量明显提高,15 d为50.20%,24 d达到67.60%,而对照仅为35%和43.30%;总产气量处理较对照提高76.81%。由此可见,菌系X1降解纤维素类物质时为甲烷合成提供了较多的前体物质,有效地提高了甲烷含量和产气量,使产气启动期提前。     

稻草与猪粪连续混合厌氧消化制备生物燃气研究

以挥发性固体(VS)比1∶1的稻草与猪粪为混合原料,采用40 L有机玻璃反应器进行连续厌氧消化,考察不同有机负荷率(OLR)(3~12 kg VS/(m3·d))及温度(55℃、35℃)对厌氧消化性能及稳定性的影响。结果表明:高温消化在整个OLR范围内,池容产气逐渐增大,最大达到4.98 m3/(m3·d),平均原料产气率为439 L/(kg VS);中温消化在OLR为12 kg VS/(m3·d)时出现严重的挥发性脂肪酸(VFAs)抑制,在稳定运行的OLR范围(3~8 kg VS/(m3·d))内,池容产气率逐渐增大,最大达到3.45 m3/(m3·d),平均原料产气率为413 L/(kg VS);用p H值判断厌氧消化系统的稳定性可能不够灵敏或具有滞后性,VFAs、碱度以及p H连续变化的监测对于诊断消化系统可能存在的不稳定因素较为有效;在高有机负荷条件下易出现污泥膨胀,中温消化系统更易形成。     

过热器再热器爆漏事故的原因分析及对策

过热器、再热器爆漏事故严重影响了锅炉机组的安全性和经济性,而造成过热器、再热器爆漏事故的主要因素有超温爆管、磨损、高温腐蚀、热疲劳、质量失控等。通过对这些因素的主要原因和爆口特征的分析,提出了一些过热器、再热器爆漏事故的防治措施。     

具有智能化特征的安全稳定分析与控制决策技术

安全稳定预警与控制辅助决策是智能电网调度技术支持系统不可缺少的应用类功能。在分析安全稳定分析与控制决策计算工作特点的基础上,提出安全稳定分析与控制决策支持智能化的主要特征：自动化和自适应性。介绍了自动化的安全稳定分析计算技术,包括输入数据准备、任务执行和输出结果的自动化处理;阐述了自适应电网运行工况、外部环境和硬件运行状态的安全稳定分析技术,包括调整应用功能的输入数据和妥善处理安全稳定性交互影响,以及根据分析计算任务要求动态优化调度计算资源。这些技术已用于安全稳定综合防御系统,提高了分析结果的适应性和分析计算的效率,在电网运行规划、计划安全校核、超短期安全态势预测、调度操作安全校核和在线分析与控制等电网调度运行管理中发挥作用。     

Hydrophilic and hydrophobic materials and their applications

Wettability of a material’s surface plays a significant role in how fluids interact with such surfaces. Wetting behavior is universal but can vary depending on the chemical nature of the solid and liquid phases. Plants and animals adapt to their environment by having evolved special properties. These properties are such as hydrophilic and hydrophobic. Hydrophilic surface has a strong affinity to water and spreading of water on such surface is preferred. The degree of hydrophilicity of the substance can be measured by measuring the contact angle between the liquid and solid phases. Hydrophobic materials are known as non-polar materials with a low affinity to water, which makes them water repelling. A contact angle of less than 90° indicates hydrophilic interaction where as an angle greater than 90° indicates a hydrophobic interaction. More recently, superwetting such as superhydrophilicity has been receiving an increased focus in the literature due to its potential significance. Superhydrophilic surface has a contact angle of less than 5°.

The fabrication of hydrophilic materials can be carried out in two main ways: depositing molecules on surfaces or modification of surface chemistry. Both methods have been successful historically in achieving their intended purposes. Hydrophobic and superhydrophobic materials can be produced with many fabrication methods such as layer-by-layer assembly, laser process, the solution-immersion method, sol-gen techniques, chemical etching, and Hummer’s method.

The applications of such an important property are significant. For example, hydrophilic surfaces can be used in anti-fogging applications, biomedical, filtration, heat pipes, and many others. Hydrophobic and superhydrophobic materials have been successfully applied in many sectors, such as: (I) the removal of petroleum from aqueous solutions, (II) applied to plastic, ceramics, and mesh to contribute to the oil removal from aqueous solutions, (III) hydrophobic layers have a strong self-cleaning effect on plastics, heat pipes, metals, textiles, glass, paints, and electronics, (IV) hydrophobic layers improve the anti-freezing behavior of heat pipes which prevents unwanted build-up and (V) they function as a water and dust protecting coat on electronics.

The presence of this property is historic but there is still a huge potential for development for its applications in many sectors such as water treatment, heat transfer applications, biomedical devices, and many more.     

Defect and impurity diagnostics and process monitoring

The review focuses on four areas of defect and impurity diagnostics: (i) the determination of parasitic resistances, (ii) quantum efficiency analysis including light-beam-induced current measurement systems which use spectrally resolved currents to determine local recombination in solar cells, (iii) methods to determine the recombination properties in solar cell precursors and (iv) techniques suitable for the recognition of the type of impurity or defect, which is responsible for increased recombination. In general, emphasis is on those methods, which are capable of delivering spatially resolved information. The use of the specific metastability features of a defect for its identification is exemplified. In addition, carrier lifetime spectroscopy methods utilising the temperature or the injection dependence of defect recombination are outlined.     

铁道机车车辆轮轨的摩擦磨损与节能降耗

阐述了铁道机车车辆轮轨摩擦磨损的现状;研究了内燃机车车轮、闸瓦和钢轨的消耗数量及相应的维修费用;指出了采用适当的新技术之后,在节能降耗方面会产生显著的经济效益。     

Hydrogen and electricity from water and light

Four self-driven photoelectrochemical hydrogen producers: n-TiO₂/p-CdTe, n-TiO₂/p-GaP, n-SrTiO₃/p-CdTe and n-SrTiO₃/p-GaP were constructed and examined in 1 M NaOH. the current-potential curves of the individual electrodes and the current-cell voltage relationships were measured. Cell current-density measurements versus time demonstrated that the output of each cell is stable for at least 12 h. the n-SrTiO₃/p-GaP cell under xenon light irradiation was the most efficient at 0·7 per cent. the n-TiO₂/p-GaP cell was estimated as the most efficient under solar light at 0·1 per cent. the stability of p-CdTe and its energy gap of 1·5 eV make it a prospect for use as a photocathode in future photoelectrochemical hydrogen producers.     

能源的开发利用与节能

在节能与环保问题成为当今全球性重要研究课题的情况下,笔者对中国能源的现状、新能源开发问题和在用车辆的环保节能问题进行了研究探讨。认为我国应加大开发可再生能源、核能源的力度,开发城市生活垃圾的新能源,找出在用柴油车实现环保节能的一些新措施。     

国内外能耗监测控制管理理论与实践

能耗监测是能源管理中的重要环节,国外不少国家在这方面都进行了积极的努力,制定了一些相关政策,并取得了一部分研究成果.我国于上世纪90年代初就出台了关于能耗监测的有关规定,2007年颁布的《单位GDP能耗监测体系实施方案》规定了能耗监测的主体、主要内容和指标.工业、交通运输和建筑是我国三大“耗能大户”,因此能耗监测研究和管理实践也主要集中在这三个领域.信息技术的发展为工业企业的能耗监测提供了基础平台,运用计算机信息技术对能耗实行现代化管理,成为企业实现信息化管理、降低成本的一种重要手段.道路交通约占我国交通运输业能耗的75％,因而对道路交通能耗的监测是交通运输业能耗监测的主要任务,而对机车能耗的监测是铁路运输能耗监测的主要内容之一.建筑能耗监测主要针对大型公共建筑,通过信息化手段进行信息采集及能耗监测.目前有关能耗监测的研究还处于起步阶段,尚未全面展开,能耗监测技术还不成熟,监测设备也不齐全.今后除了要继续探索能耗监测技术以外,还应重点加强对主要行业能耗监测控制管理体系的研究.     

The roles of science and technology in energy and environment research and development

Countries are becoming increasingly aware of the importance of science and technology in relation to national development and the necessity of formulating a concise science and technology policy. The need to strengthen and orient the scientific and technological infrastructure in line with national development goals, through more effective use of an available qualified work force and the higher education system, is becoming widely recognized. Consequently, appropriate methods of assessing the impact of science and technology on national development are needed so that efforts are concentrated on areas potentially having substantial impacts. Numerous planning studies have been undertaken to this end, particularly by international organizations such as UNESCO, UNIDO, OECD and IEA. This study examines the inter‐relationships of the disciplines of science and technology with energy and environment research and development (R&D) activities, particularly for developing countries. The connections between these topics are discussed along with some basic methods that can be used to exploit the relations. Some illustrative examples are presented. It is anticipated that the present study will serve as a preliminary step for more comprehensive work by providing an example of the utilization of formal methods in formulating science and technology policy for energy and environment R&D. Copyright © 2001 John Wiley & Sons, Ltd.     

火电厂TSI安装调试及常见故障诊断和处理

火电机组TSI探头的安装与调试是一个较为复杂和精细的工作.是火电厂热控安装不可或缺的最重要的组成部分.文章对各种测量探头的原理进行了分析,理论结合实际,将原理图和现场安装图进行对照,通俗易懂.对这些TSI探头在实际安装时应注意的细节问题做了详尽的阐述,同时对试车过程中出现的问题进行了分析并提出了处理措施.对火电机组汽轮机本体热工仪表安装工作有一定的指导意义.