双向蒸汽流量的测量

双向蒸汽质量流量测量是一项特殊的流量测量课题。双向孔板不切斜角,节流件两个端面均应符合国家标准中关于上游端面的规定,节流件的两个直角边均应符合国家标准中关于上游边缘的规定。通常采用2台差压变送器分别测量正反向差压,用1台压力变送器测量正向流正端取压口压力,并根据关系式计算反向流正端口取压口压力,几路信号送流量二次表判断流动方向和计算蒸汽质量流量。双向孔板流量计可按JJG640规程用几何法进行检定。另外,对于要求不高的测量点,也可用菱形截面阿牛巴均速管流量计测量。时差法超声流量计也具有双向流测量能力,可用导波板降低外夹式换能器安装处的温度,用于温度不高于400℃的蒸汽双向流测量。     

用涡街流量计测量蒸汽的质量流量

介绍了用涡街流量计测量蒸汽的质量流量的原理，以及蒸汽相变对测量的影响。     

双向大量程比蒸汽流量计的工程实践

介绍使用双向标准孔板实现双向蒸汽流量测量的基本原理。定量计算分析流出系数、可膨胀性系数以及测量不确定度与流量的关系,并讨论制约标准孔板流量计提高量程比的几个主要因素。通过定量计算对比单一大量程变送器和一大一小双量程变送器对不确定度的影响,论证增加1台小量程变送器用于小流量测量、以达到30∶1量程比的技术方案的可行性。介绍应用HART总线降低项目投资的技术方案。论述流量计设计和选型以及施工中应特别关注的几个因素和细节。     

Endress+Hauser推出全新的Prowirl 200涡街流量计

<正>在涡街流量计的应用中,近40%用于测量饱和蒸汽。如何检测湿蒸汽或者精确测量蒸汽干燥度,一直是饱和蒸汽测量过程中难以攻克的技术难点。日前,Endress+Hauser在全新流量产品平台New Proline的基础上,发布了新一代两线制涡街流量计Prowirl 200,完美解决湿蒸汽报警和测量的问题。该产品提供目前世界上涡街流量中领先的湿蒸汽探测与测量功能,在流量测量的同时提供对     

孔板流量计用于蒸汽测量

锥形孔板流量计在稠油单井注汽中的应用,解决了常规流量计同时难以计量蒸汽流量和干度的问题,安装简单,操作方便.该流量计能实时测量单井注汽量和干度变化,能够适应不同范围干度和蒸汽的测量,给稠油开采地质动态分析提供了准确可靠的计量数据.根据蒸汽量的量程及最大差压,为保证蒸汽流量和干度的测量准确度,建议最小流量工作在最大量程的3%以上.2010年百重七油田进行蒸汽驱试验,采收率提高了6%.     

Endress＋Hauser推出全新的Prowirl200涡街流量计

在涡街流量计的应用中，近40％用于测量饱和蒸汽。如何检测湿蒸汽或者精确测量蒸汽干燥度，一直是饱和蒸汽测量过程中难以攻克的技术难点。日前，Endress＋Hauser在全新流量产品平台NewProline的基础上，发布了新一代两线制涡街流量计Prowirl200，完美解决湿蒸汽报警和测量的问题。     

权威机构测试 艾默生高准品质卓越——艾默生高准（Micro Motion）质量流量计顺利通过中国最权威天然气实流测试

近日，艾默生旗下的高准公司宣布，其所生产的质量流量计于2007年末顺利通过了中国最权威的原油大流量计量站成都天然气流量分站（CVB）的天然气实流测试。CVB参照JJG897—1995质量流量计鉴定规程，对高准公司提供的1台DN50科里奥利流量计在多种安装条件下进行天然气实流测试。测试结果表明：艾默生高准公司的质量流量计在天然气测量上，不但完全满足0．5％的精度，而且还具有良好的重复性，不受气体流态的影响，安装灵活，双向测量等特点。     

高纯气体流量测量中的仪表选型

高纯气体具有组分稳定,无尘、无水滴、无油污的特点,为流量测量和流量计的稳定运行创造了良好的条件.通过对比差压式流量计和热式质量流量计的工作原理及在高纯气体实际测量中的应用,介绍了选用两种流量计的条件,分析了差压式流量计和热式质量流量计在实际测量中存在的误差原因,并给出了相应解决方案.     

用孔板流量计和临界流量计的压力数据来确定蒸汽的质量和流量

一种测量蒸汽质量和流量的方法已经在实验室试验和热力提高采收集中得到应用，该方法包含一个与临界流量计串联的孔板流量计。流体通过孔板是低于临界点的。这个临界流量计可能是静态节流器、文丘里管、喷咀或一个厚的孔板等。     

浅析超声流量计在原油计量中的应用

从二十世纪七十年代以来，液体超声流量计主要用于清污水的测量，其流量测量结果不确定度一般低于0．5％。受到气体多声道超声流量计的启发，目前多家公司已开发出可用于原油计量的多声道超声流量计，流量测量结果的不确定度可达到0．2％。多声道液体超声流量计具有测量准确度高、测量范围宽，无可动部件、无压力损失、可双向测量及自诊断功能强等特点。超声流量计原理上不受大管径限制，与同口径的其它流量计相比，在大口径、高压液体流量测量方面更具有优势，可以测量更高的上限流量。     

EFFECT OF SOLVOLYTIC EXTRACTION AND PYROLYSIS PRETREATMENTS ON THE TOEMPRATURE STEAM GASIFICATION REACTTVITY OF COAL AND REDUCTION OF TAR FORMATION IN PRODUCT GASES

Pre-extraction of Talcher coal ( a bituminous coal) in anthracene oil was found to be a beneficial treatment for enhancing the reactivity for steam gasification of coal. Similarly, anthracene oil followed by liquid paraffin extraction of coal was also found to be a-better pretreatment for the steam gasification of coal. Anthracene oil extraction at 270°Cand steaming of coal at 650°C had almost equal effect on steam gasification of coal. Pyrolysis in steam of pre-extracted coals was found to further enhance the reactivity of coal for steam gasification. The studies were further confirmed by carrying out thermogravimetric analysis of pretreated coals in steam atmosphere. Degree of cross-linking in pretreated coals was studied by measurement of swelling of coal in quinoline. The formation of tar in gaseous product was reduced as a result of pre-extraction and steam pyrolysis of coal prior to their gasification in steam.     

EFFECT OF SOLVOLYTIC EXTRACTION AND PYROLYSIS PRETREATMENTS ON THE TOEMPRATURE STEAM GASIFICATION REACTTVITY OF COAL AND REDUCTION OF TAR FORMATION IN PRODUCT GASES

ABSTRACT

Pre-extraction of Talcher coal ( a bituminous coal) in anthracene oil was found to be a beneficial treatment for enhancing the reactivity for steam gasification of coal. Similarly, anthracene oil followed by liquid paraffin extraction of coal was also found to be a-better pretreatment for the steam gasification of coal. Anthracene oil extraction at 270°Cand steaming of coal at 650°C had almost equal effect on steam gasification of coal. Pyrolysis in steam of pre-extracted coals was found to further enhance the reactivity of coal for steam gasification. The studies were further confirmed by carrying out thermogravimetric analysis of pretreated coals in steam atmosphere. Degree of cross-linking in pretreated coals was studied by measurement of swelling of coal in quinoline. The formation of tar in gaseous product was reduced as a result of pre-extraction and steam pyrolysis of coal prior to their gasification in steam.     

裂解炉汽包液位测量系统的改进

以裂解炉的汽包液位测苗为例，阐述了裂解炉汽包液位的测量原理，分析了环境温度和引压管的长度对仪表测量精度的影响，匪点介绍了汽包液位的压力补偿原理及补偿在DCS中实现的方法，并对改进后的测量值进行了比较，提高了汽包液位测量值的精确度。     

赤铁矿作用下煤化学链气化过程碳氮元素转化机理

以赤铁矿为载氧体,利用流化床反应装置比较传统煤气化与化学链煤气化的不同特性,同时研究气化温度、水蒸气流量、赤铁矿/煤比(即氧/碳摩尔比)、燃料种类等反应条件对化学链气化特性的影响,并分析气化反应后载氧体基本特性的变化。结果表明,化学链气化呈现2个不同的反应阶段。在初始的挥发分析出阶段,还原性气体与载氧体、NOx的氧化还原反应对碳、氮元素的转化具有重要影响,NO和N2O均明显析出;在煤焦气化阶段,载氧体能够提高半焦反应活性、促进半焦气化和N2O生成,N2O是主要的NOx产物。赤铁矿载氧体中的Fe2O3在气化过程被还原、部分转化为Fe3O4,未发现载氧体烧结现象。     

煤粉流量测量技术及应用

对于干煤粉气化工艺的密相输送系统来说,煤粉质量流量的测量非常重要。介绍几种当前常用或较为热门的气固两相流固体质量流量测量方法,使用密度速度测量技术对国内某大型煤化工气化工艺中密度速度测量应用方法进行分析,给出系统的密度计、速度计及二次仪表选型和测试方法,最后对系统中的测量数据进行分析,确定该方法的优越性。     

CATALYTIC EFFECTS OF CALCIA (CaO) ON THE GASIFICATION OF COAL MACERALS

The catalytic effect of calcium oxide in the steam and carbon dioxide gasification of the three Pingshuo coal materials, vitrinite, liptinite and fusinite by a DTA-GC apparatus in a temperature range of 773-1373K at a heating rate of 10 K/min is reported. The gasification pressure was selected as 1.0 MPa (total) for CO² and 10 KPa (partial) for steam. The results show that the catalytic effect of CaO mixed in the macerals is more obvious for CO² gasification than for steam gasification. The effect is related to both specific surface and chemical structure of the macerals. Based on DTA data the kinetic parameters of the CO² and steam gasification reaction of the macerals with different CaO-additive amount were obtained.     

低阶煤固定流化床热解及半焦气化实验研究

采用固定流化床研究了三种低阶煤的常压热解及其热解半焦的气化特性,探究了样品粒度、反应温度、反应时间及流化气中O2含量对上述过程的影响,确定了循环流化床热解-气化耦合工艺适宜的反应条件。结果表明,在实验选择范围内,样品的粒度基本不会影响热解过程,在水蒸气气氛下,温度越高,热解气体产率越高,半焦产率越低;600 ℃和20 min时能获得最高的焦油产率。循环流化床热解-气化耦合工艺碳的有效利用率率高于原煤固定流化床气化工艺,同时副产煤焦油;温度越高,有效气产率和有效碳转化率越高;实验范围内,O2含量对合成气产率的影响较小,但可以调节H2和CO的相对含量;900 ℃、半焦气化15 min即可获得较理想的合成气产率及有效碳转化率。     

石油焦水蒸气气化反应的实验研究

在固定床气化反应器中,考察了石油焦粒径、水蒸气流量、温度、压力和氧气量对石油焦水蒸气气化反应的影响。结果表明,当石油焦粒径小于380 μm、水蒸气流量高于0.85 g/min时,基本消除了内外扩散对石油焦水蒸气气化反应的影响;在消除内外扩散影响的前提下,随着反应温度和压力的升高,石油焦气化反应速率呈现增加的趋势,其中温度对石油焦气化反应速率的影响更大,气化产物中H2含量逐渐降低,CO含量逐渐增加。反应系统中氧气的加入,不仅与石油焦发生燃烧反应放出热量,还与生成的H2和CO发生反应。因此,必须合理优化反应条件和开发配套反应设备,以保证气化反应快速高效地进行。     

流化床反应器超温原因分析及对策

KSY技术单炉处理能力大,作为典型的高倍率双循环流化床煤粉气化技术之一,由2段流化床反应器耦合构成.经过100 t/d中试装置数十次试验发现,技术关键点是炉温的精准控制,2段反应器极易出现局部超温现象,超温引发结渣,就会导致紧急停车.文中通过煤质、蒸汽温度、工艺条件、物料混合详细分析造成炉温波动的原因,为下次试验和工程...     

Modeling Steam Gasification of Orimulsion in the Presence of KOH: A Strategy for High-Yield Hydrogen Production

Production of hydrogen rich gases from heavy oils via potassium-catalyzed steam gasification is a promising approach toward cleaner fuel production, suitable for fuel cell applications. The authors developed a zero-dimensional mathematical model to simulate the steam gasification of Orimulsion with KOH as a catalyst, based on an equilibrium model. The model is compared with the numerical results and data from an experimental study, showing a good agreement with it. This research activity presents a large number of predicted data of catalytic gasification, aiming to survey the effects of reaction temperature, gasification pressure, steam/fuel ratio, and KOH/fuel ratio on gas product compositions. It also provides useful indications for its optimal choice. Results illustrate that the pressurized operation slightly increases methane concentration as well as the production of higher heating value gas, while decreasing the hydrogen concentration.