火电机组脱硫CEMS系统升级改造的策略与应用

湿法脱硫是我国煤电行业的主导技术,由于湿法脱硫烟气排放过饱和,含有大量的水分,对SO2的测定带来巨大的干扰。利用现有的SO2测量方法,特别是针对超低排放的湿法脱硫技术,需要考虑烟气中水分的影响。石灰石-石膏湿法脱硫后烟气冷凝水的pH值为2,低于脱硫浆液,说明脱硫后烟气携带的水中溶解了部分SO2。为了避免水的干扰,红外线在线连续排放监测系统(CEMS)配备了一个除水装置。采用传统的冷凝水脱除方法时,冷凝水溶解SO2,导致烟气中SO2浓度相对较低。采用适当的除水方法,可有效避免因SO2溶于凝析水而引起的测量误差。     

煤化工废水零排放处理方法研究

文中提出一种煤化工废水零排放处理方法,文中方法在常规预处理和生化处理的基础上,采用活性焦吸附和多级膜分离技术进行深度处理.所得淡水水质达到工业循环水使用要求,做循环水使用;所得浓水PH值8～10,富含钙、镁等金属离子和少量氨氮,加入一定比例的CaCO3或CaO,制成脱硫浆料,送入燃煤锅炉烟气脱硫净化系统,作为半干法或湿法脱硫的脱硫剂使用,也可直接做循环流化床半干法烟气脱硫增湿水使用.从而可实现煤化工废水的完全循环利用和零排放处理,利用膜分离所得浓水脱硫,可降低烟气脱硫系统的钙硫比和操作成本,具有节水、环保的优点.     

一种采用热泵装置消除烟囱白色烟羽的技术路线

火电厂的烟气经过湿法脱硫系统处理后排放。排放烟气中携带大量饱和水蒸气,排放到大气后,在烟囱出口处形成了浓重的白色烟羽。上海、浙江、天津等多省市均要求火电行业对白色烟羽进行治理。分析白色烟羽形成的原因,从节能、环保的角度考虑,提出一种采用热泵装置对脱硫后烟气先进行冷凝除水,然后对烟气进行加热处理的技术路线,在尽量降低能耗的情况下,通过提高排烟温度来消除烟囱的白色烟羽,同时能够回收烟气中的大量水分,降低脱硫系统水耗。     

Mg(OH)2在烟气脱硫中的应用

我国烟气脱硫以石灰石一石膏法脱硫工艺为主。叙述了Mg（OH）2的性能特性和在烟气脱硫中的应用。指出，镁剂烟气脱硫作为一种绿色环保的SO2减排技术，可成为我国脱硫技术的主导工艺，具有较大的发展前途。     

烟气脱硫脱硝除尘超低排放技术在自备电站锅炉综合改造中的应用

简要说明锅炉烟气净化装置改造的必要性,并对当前可用的超低排放技术方案进行对比分析。详细介绍烟气循环流化床半干法同时脱硫脱硝和除尘超低排放技术。项目改造后,实现了排放烟气中SO2、NOx及烟尘的浓度远低于国家要求的超低排放值。所采用的DSC-M干式超净+同时脱硫脱硝除尘装置具有较优的技术和经济优势。     

炼厂加热炉烟气与工艺废气达标排放分析探讨

烟气氮氧化物和二氧化硫的排放控制已成为炼油企业关注的重点。对加热炉烟气、催化裂化装置、硫磺回收装置和废酸再生装置的工艺废气的排放控制进行探讨,从操作优化与技术改造两方面提出应对措施。对氮氧化物排放不合格的燃气加热炉,采用低氮燃烧器进行改造,以满足特别限值排放地区NOx排放限值100mg/m3的标准;导致惠州炼化燃料气硫含量偏高的主要因素是催化/焦化干气硫含量偏高、气柜回收瓦斯未脱硫。通过提高干气脱硫能力、对火炬系统气柜回收瓦斯脱硫后再补入燃料气系统,可满足加热炉烟气二氧化硫排放标准。催化裂化装置通过加入脱硝助剂,催化烟气中NOx由640mg/m3降至85mg/m3左右,满足特别排放限值地区NOx排放标准。增上催化烟气湿法脱硫除尘措施,可满足催化烟气SO2排放标准。硫磺回收装置通过液硫脱气改造,并采用高效复配脱硫剂,可满足尾气SO2排放标准。废酸再生装置通过操作优化与增加尾气洗涤系统,其烟气可满足国家最新排放标准。     

造纸废水用于燃煤锅炉烟气的脱硫除尘技术

介绍了当前国内利用大量排放的造纸废水进行燃煤锅炉烟气脱硫除尘的技术,论述了废水pH值,进气SO2浓度,气水比对燃煤烟气脱硫的影响,并对其进行了技术经济分析。     

低氮燃烧及炉内脱硫技术在75 t/h循环流化床锅炉上的应用

以循环流化床锅炉为研究对象,重点研究了烟气再循环、SNCR和炉内脱硫对锅炉NO_x和SO_2排放的影响。在一台75 t/h循环流化床锅炉上的改造实验表明,烟气再循环可明显降低NO_x初始排放,再循环烟气比例为32%时,NO_x初始排放由420 mg/m~3降低至280 mg/m~3。烟气再循环还可提高炉膛温度分布的均匀性,结合SNCR技术可将NO_x最终排放降低至80 mg/m~3。在合适的温度条件下应用炉内脱硫可大幅降低锅炉SO_2初始排放,脱硫率超过60%。     

石化企业烟气脱硫技术及选择

介绍了石化企业常用的脱硫技术,并分析了各技术的优缺点。分析了石化企业烟气SO2排放及脱硫现状,指出石化企业在选择烟气脱硫技术时需考虑的因素有：企业所处地理环境和SO2排放要求,锅炉规模、建设年限及燃料结构,脱硫剂市场情况及品质要求,脱硫副产物利用情况,脱硫装置运行成本等。提出了有关石化企业减少SO2排放和烟气脱硫技术选择的建议。     

焦炉烟气脱硫脱硝余热回收一体化研究应用

就目前而言,我国在发展的过程中离不开煤炭工业,因此,为了能够有效避免环境污染等问题的发生,我国在管理和控制炼焦化学工业污染物排放的时候,出台了更加严格的标准,相关的化工型技术科研人员也在不断的研究和开发新型的脱硝催化剂等。采用新型的镁法烟气脱硫工艺等对炼焦化学工业污染物排放进行控制,可以更好地满足和符合我国相关法律法规,有效降低对环境的污染和对人们身体的危害。通过采用焦炉烟气脱硫脱硝余热回收一体化技术,有效解决了焦炉烟道气脱硫脱硝及余热回收利用的问题,使经济效益得到有效提高,因此,针对焦炉烟气脱硫脱硝余热回收一体化技术进行分析研究,对相关技术展开说明,从而更好的提高化工企业的科研、环保能力。     

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．