低低温电除尘及高效电源协同烟气处理技术的应用

为研究低低温电除尘及高效电源协同烟气处理技术的应用效果,以一循环流化床锅炉为研究对象,通过试验方法,对协同烟气处理技术投运前后烟气中的粉尘颗粒特性及排放质量浓度进行了测量及对比,并对该技术投运后的经济性进行了分析。结果表明:协同烟气处理技术投运后,机组排放的粉尘质量浓度由49.5 mg/m³降低至10.7 mg/m³,可显著提高除尘器的除尘效率;可降低机组供电标煤耗2.835 g/(kW·h),年节煤量1473.5 t;可进一步减少CO₂,SO₂,NO_x及粉尘等污染物的排放;可节约用电160 kW·h/h,每年节约电量6.16×10⁵ kW·h。     

火电厂尾部增设低温换热器的节能效果研究

通过对北方某电厂135 WM机组进行烟气余热回收装置的设计计算,将低温烟气余热回收装置布置于机组吸风机出口至脱硫增压风机入口烟道上,本装置可全年投运,具有良好的节能环保效益,经计算BMCR工况下可回收烟气余热6 MW,本装置在采暖期可为机组增加直接收益200.6万元每年,节水收益12.1万元每年;还间接提高脱硫除尘效率,降低脱硫电耗。     

烟尘排放综合治理技术在某循环流化床机组的应用研究

文章以某循环流化床机组为例,分析了机组存在的烟尘排放浓度偏高问题,提出了高效电源技术与低低温省煤器相结合的烟尘排放综合治理技术。改造完成后,对经济性进行了分析,得出以下结论:高效电源及低低温省煤器改造后,可有效提高电除尘器的除尘效率,烟尘排放浓度由49. 5 mg/Nm~3降低至25 mg/Nm~3。此外,高效电源改造后,除尘器电源的节电效果显著,每年可节约用电61. 6万kW·h;低低温省煤器改造后,除尘器入口烟气温度大幅降低,非供热季可降低除尘器入口烟气温度64℃,降低机组发电标煤耗2. 8 g/(k W·h);供热季可回收热量47 GJ/h。     

660 MW超超临界机组低温省煤器配置方案研究

利用低温省煤器吸收烟气余热,可降低煤耗,减少脱硫系统耗水量,提高全厂热效率.本文以某660MW超超临界燃煤电厂为例,对低温省煤器设置在除尘器前、吸风机后及除尘器前和除尘器后分别布置三种配置方案进行分析,并进行技术经济比较.研究表明,除尘器前和吸风机后分别设置两级低温省煤器供电收益最大,在燃煤量不变的情况下,可降低标准煤耗2.3g/kWh,单台机组年节水34.65万t.     

新型高效除尘器提效改造技术

针对华能国际电力股份有限公司上安电厂6号600MW超临界机组电除尘器除尘效率低、排放超标进行设备改造,采用综合的“低低温＋高频电源控制技术＋末电场复合双区技术扩容”除尘器提效改造新技术,连同脱硫系统的除尘作用,达到了烟囱排放小于20 mg/Nm3的目标,可在大型机组除尘器提效改造工程中推广.     

百万千瓦燃煤机组烟气超低排放设计及应用

为实现燃煤机组烟气超低排放,对某电厂1 000 MW燃煤机组实施烟气超低排放的技术改造:脱硝采用低氮燃烧器调整技术和SCR反应器内加装催化剂技术,除尘采用低低温电除尘器和湿式电除尘器,脱硫采用交互式喷淋技术。改造后机组烟气排放按下述流程:低氮燃烧器的锅炉出口烟气依次流经省煤器、SCR、空预器、管式换热器降温段、低低温电除尘器后进入吸收塔,然后经过湿式静电除尘器和管式换热器升温段进入烟囱。改造后烟囱入口的主要烟气污染物NO_x、烟尘、SO_2排放浓度分别达到25.83、1.61和22.08mg/Nm~3,污染物排放浓度数值上低于天然气燃气轮机组排放标准。     

循环流化床烟气脱硫装置对电除尘器影响研究

在一台75t／h燃煤锅炉上，设计建造了双循环流化床烟气悬浮脱硫系统，在脱硫系统运行前后，对配套电除尘器入口处烟气的温度、湿度、化学成份、粉尘的粒径、表观形貌和比电阻等相关特性进行了比较分析。结果显示，在脱硫系统运行后，可使除尘器入口处烟气的湿度增加，温度降低，尘粒的比电阻下降，从而提高了系统的脱硫效率与电除尘器的除尘效率。还研究了循环流化床烟气脱硫装置对电除尘器工作稳定性和除尘效率的影响，同时提出了应对措施。     

660MW机组锅炉增设低温省煤器的经济性分析

排烟热损失是锅炉各项热损失中最大的一项,影响排烟热损失的主要因素是排烟温度。电站锅炉在尾部烟道加装低温省煤器,利用排烟余热加热凝结水,可以降低脱硫系统的入口烟温。以国内某660 MW超超临界机组为研究对象,用等效焓降法对低温省煤器的节能效果进行了计算分析。结果表明:投运低温省煤器后,发电煤耗降低2.33 g/k Wh,节能效果显著;与国内同类型采用回转再生式原烟气/净烟气换热器的机组相比,引风机比压能下降约1 000 Nm/kg,工况点也得到了明显改善。     

与袋式除尘器配套的半干法烟气脱硫技术及应用

循环流化床半干法烟气脱硫除尘一体化工艺（DSDFP）是对半干法脱硫丁艺的改进。该工艺的特点是在脱硫塔的前后分别设置一台电场静电除尘器和一台低压脉冲袋式除尘器，电场静电除尘器对烟气进行预除尘，袋式除尘器对脱硫塔出口的高含尘烟气进行除尘。银川热电厂150t／h燃煤锅炉应用了DSDFP系统并进行了运行试验。运行试验结果表明，当进料钙硫比（Ca／S）为1．3、近绝热饱和温度（△T为15℃时，系统的脱硫效率可达85％，烟尘排放浓度小于50mg／m^3，满足目前的环保要求。针对DSDFP系统在经过一段时间运行后出现的布袋除尘器压差增大、锅炉负压不稳定、脱硫塔壁面结垢、塔内喷嘴堵塞等问题，经分析采用控制喷水量、优化水喷嘴布置、严格控制雾化角和喷射距离、在脱硫塔内采用双流体喷嘴、合理设计塔内烟气流场等措施进行解决。     

燃煤机组烟气余热及水协同回收系统结构参数优化研究

为了提高燃煤发电机组效率、降低机组水耗,本文针对烟气余热及水协同回收系统展开研究.该系统通过烟气换热器降低烟气温度至95℃,回收低温烟气余热的同时降低脱硫塔耗水量,并通过烟气冷凝器回收烟气中的水分,实现节能与节水的协同.本文研究了系统的运行特性,发现其有良好的节能节水潜力,同时研究了系统换热器面积及冷凝水质量流量对系统运行参数及性能的影响,发现低温省煤器、烟气冷却器、烟气再热器面积和低温省煤器冷凝水质量流量降低可以提高进入电除尘器烟气温度,为系统变工况运行调控、防止低温腐蚀提供指导.     

Performance assessment of some ice TES systems

In this paper, a performance assessment of four main types of ice storage techniques for space cooling purposes, namely ice slurry systems, ice-on-coil systems (both internal and external melt), and encapsulated ice systems is conducted. A detailed analysis, coupled with a case study based on the literature data, follows. The ice making techniques are compared on the basis of energy and exergy performance criteria including charging, discharging and storage efficiencies, which make up the ice storage and retrieval process. Losses due to heat leakage and irreversibilities from entropy generation are included. A vapor-compression refrigeration cycle with R134a as the working fluid provides the cooling load, while the analysis is performed in both a full storage and partial storage process, with comparisons between these two. In the case of full storage, the energy efficiencies associated with the charging and discharging processes are well over 98% in all cases, while the exergy efficiencies ranged from 46% to 76% for the charging cycle and 18% to 24% for the discharging cycle. For the partial storage systems, all energy and exergy efficiencies were slightly less than that for full storage, due to the increasing effect wall heat leakage has on the decreased storage volume and load. The results show that energy analyses alone do not provide much useful insight into system behavior, since the vast majority of losses in all processes are a result of entropy generation which results from system irreversibilities.     

Effect of co-cultivation of Chlamydomonas reinhardtii with Azotobacter chroococcum on hydrogen production

Chlamydomonas reinhardtii cc124 and Azotobacter chroococcum bacteria were co-cultured with a series of volume ratios and under a variety of light densities to determine the optimal culture conditions and to investigate the mechanism by which co-cultivation improves H₂ yield. The results demonstrated that the optimal culture conditions for the highest H₂ production of the combined system were a 1:40 vol ratio of bacterial cultures to algal cultures under 200 μE m^?2 s^?1. Under these conditions, the maximal H₂ yield was 255 μmol mg^?1 Chl, which was approximately 15.9-fold of the control. The reasons for the improvement in H₂ yield included decreased O₂ content, enhanced algal growth, and increased H₂ase activity and starch content of the combined system.     

Exergetic evaluation of 5 biowastes-to-biofuels routes via gasification

This paper presents the exergy analysis results for the production of several biofuels, i.e., SNG (synthetic natural gas), methanol, Fischer–Tropsch fuels, hydrogen, as well as heat and electricity, from several biowastes generated in the Dutch province of Friesland, selected as one of the typical European regions. Biowastes have been classified in 5 virtual streams according to their ultimate and proximate analysis. All production chains have been modeled in Aspen Plus in order to analyze their technical performance. The common steps for all the production chains are: pre-treatment, gasification, gas cleaning, water–gas-shift reactions, catalytic reactors, final gas separation and upgrading. Optionally a gas turbine and steam turbines are used to produce heat and electricity from unconverted gas and heat removal, respectively. The results show that, in terms of mass conversion, methanol production seems to be the most efficient process for all the biowastes. SNG synthesis is preferred when exergetic efficiency is the objective parameter, but hydrogen process is more efficient when the performance is analyzed by means of the 1st Law of Thermodynamics. The main exergy losses account for the gasification section, except in the electricity and heat production chain, where the combined cycle is less efficient.     

液压系统常见的故障诊断及处理

任何工程机械式液压设备使用时出现故障是不可避免的。但是怎样确定故障的原因及找到好的解决方法，这是使用者最关心的问题。讲述了液压系统常见的故障及其排除方法。     

Economie d'énergie en trigénération

Trigeneration is defined as the production of three useful forms of energy—heat, cold and power—from a primary source of energy such as natural gas or oil. For instance, trigeneration systems typically produce electrical power via a reciprocating engine or gas turbine and recover a large percentage of the heat energy retained in the lubricating oil, exhaust gas and coolant water systems to maximize the utilization of the primary fuel. The heat produced can be totally or partially used to fuel absorption refrigerators. Therefore, trigeneration systems enjoy an inherently high efficiency and have the potential to significantly reduce the energy-related operation costs of facilities. In this paper, we describe a model of characterization of trigeneration systems trough the condition of primary energy saving and the quality index, compared to the separate production of heat, cold and power. The study highlights the importance of the choice of the separate production reference system on the level of primary energy saving and emissions reduction.     

Mineralogical characterization of the intraseam layers of Lofoi lignite deposits in Florina basin (western Makedonia,northwest Greece)

The mineralogical composition of intraseam layers from Lofoi lignite deposits (northwest Greece) is the subject of the present study. The samples were examined by means of X-ray diffraction (XRD), thermo-gravimetric (TG/DTG) and differential thermal analysis (DTA), and Fourier transform infrared (FT-IR) spectrometry. The clay minerals prevail in most samples, with illite-muscovite being the dominant phase, and kaolinite and chlorite being the other major clay components. No smectite was found. Quartz and feldspars, dominate in two cases. The studied materials are characterized as clays to clayey sands, showing significant similarities with the intraseam layers of the adjacent Achlada lignite deposits.     

Innovative methodologies in renewable energy: A review

This paper is concerned with innovative approaches to renewable energy sources computation methodologies, which provide more refined results than the classical alternatives. Such refinements provide additional improvements especially for replacement of fossil energy usages that emit greenhouse gas (GHG) into the atmosphere leading to climate change impact. Current knowledge gap among each renewable energy source calculation is rather missing fundamentals of plausible, rational, and logical explanations for the interpretation of results. In the literature, there are rather complicated and mechanically applicable methodologies, which require input and output measurement data match with missing physical explanations. The view taken in this review paper is to concentrate on quite plausible, logical, rational, and effectively applicable innovative energy calculation methodologies with simplistic fundamentals. For this purpose, a set of renewable energy methodological approaches is revisited with their innovative structures concerning solar, wind, hydro, current, and geothermal energy resources. With the increase in the renewable energy utilizations to combat the undesirable impacts of global warming and climate change, there is a need for better models that will include physical environmental conditions and data properties in the probabilistic, statistical, stochastic, logical, and rational senses leading to refined and more reliable estimations with application examples in the text. Finally, new research directions are also recommended for more refined innovative energy system calculations.     

Constrained Optimization of Heat Transfer from an Extended Surface

Two different zero‐order optimization techniques are used to maximize the rates of heat transfer from a fin assembly of a specified cost and in the shape of several annular fins that are mounted on a central stem. The problem is formulated to account for two‐dimensional steady‐state heat transfer that is limited by several inequality constraints. The dimensionless governing equations are used to identify the relevant decision variables. The number of fins making up the assembly is treated as an input parameter. A digital computer is used to determine the required temperature distributions and to implement the optimization search algorithms. Three different fin materials are assessed—aluminum, copper and carbon steel. Design optimizations of the extended surface assembly were made over a range of operating conditions, encompassing several different convection heat transfer coefficients that are representative of free and forced convection in air, and several different overall temperature differences between the substrate surface and air. A few recommendations based on trends in the predicted results are given. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res, 43(6): 504–521, 2014; Published online 3 October 2013 in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.21093     

CY6D78Ti型柴油机的开发研制

本文介绍了CY6D78Ti型柴油机的开发研制过程及现状,CY6D78Ti型柴油机能满足国内中、重型卡车和豪华客车市场对柴油机动力性、经济性、可靠性的需求。由于该机型的高档配置,保证了其排放达到欧Ⅱ标准,同时为进一步提高性能、降低排放,采用电控及高压共轨等技术手段搭建了平台。     

我国车用柴油机的技术现状及发展趋势

本文根据国内外信息和资料，分析了我国目前车用柴油机制造技术方面与国际水平所存在的差距，预测今后若千年内车用柴油机要向节能降耗、应用增压技术、提高可靠性、降低排放、采用电控技术方面发展，以尽快接近和赶上国际先进水平．