降低蒸汽直接加热氯化钾溶液噪声的研究

在蒸汽直接加热氯化钾溶液的过程中,产生的蒸汽喷射噪声主要有冲击振动噪声、湍流噪声及蒸汽泡破灭噪声,其中,蒸汽泡破灭噪声占主要地位。试验研究了氯化钾溶液温度、蒸汽流量、蒸汽压力、蒸汽温度、蒸汽流速、喷孔面积、喷孔直径、喷孔间距等因素对噪声的影响,试验与研究结果表明,降低蒸汽喷射噪声关键在于减小蒸汽泡大小,应选择较小喷孔孔径、较大喷孔间距、较多喷孔数量与较小蒸汽压力。     

直埋蒸汽管安装的要点

直埋蒸汽管是最近几年在蒸汽管道安装使用的一种组合材料,其由蒸汽管、保护钢管、保温层、蒸汽管固定架及防腐层等组合而成,与管廊蒸汽管、架空蒸汽管相比具有不占空间、不占用地、不易受损、不影响环境等优点。本文介绍了直埋蒸汽管的施工程序,从材料进货检验,蒸汽管道焊接、保护管道焊接、蒸汽管蒸汽吹扫及管道回填等施工过程中的要点、施工方法及应该注意事项,严格整个过程控制。     

装置内蒸汽主管道布置及应力浅谈

石油化工装置内蒸汽主管道一般布置在主管桥上,向各个蒸汽使用点提供蒸汽。一般蒸汽有吹扫、伴热、提供热源、驱动设备等多种用途。蒸汽有低压蒸汽、中压蒸汽、过热蒸汽等区分,但是其布置原则大同小异,此处不做特别区分。由于蒸汽管道温度高,热涨大,很容易对管桥结构和分支管产生很大影响,所以布置时要特别小心。因此运用石油化工行业压力管道专业常用应力分析软件CAESARⅡ,分析了蒸汽管道布置时需要注意的问题。     

明瑞公司硫酸余热蒸汽综合利用与蒸汽平衡

通过对硫酸余热蒸汽几种利用方式的比较,提出了蒸汽特别是二次蒸汽(低压蒸汽)的合理利用顺序为石膏粉车间、磷铵车间、余热发电。同时为了平衡各单位的蒸汽用量,提出了对蒸汽实行量化管理的方案。     

浅析利用管道模拟软件对低压蒸汽(1.37MPa)管网现状的模拟及优化

某公司蒸汽管网系统错综复杂,分为高压蒸汽、中压蒸汽、低压蒸汽及低低压蒸汽管网,同时存在高压、中压、低压蒸汽减温减压系统及部分生产装置副产中压、低压蒸汽,为了更好的了解该公司蒸汽管网实际运行情况,查找在运行过程中蒸汽的温度、压力、流量的分布,利用管道模拟软件对该公司低压蒸汽(1.37MPa)系统进行模拟,通过模拟查找低压蒸汽管网在实际运行过程中存在瓶颈,并提出针对性改造措施,达到节能降耗目的。     

燕山乙烯装置蒸汽网络的现状分析与优化方向

介绍了燕山乙烯装置在用蒸汽网络的匹配情况。目前装置消耗蒸汽主要有4种,按蒸汽压力等级划分,分别是10.0 MPa超高压蒸汽（SS）、1.5 MPa中压蒸汽（MS）、0.3 MPa低压蒸汽（LS）和0.25MPa次低压饱和蒸汽（PS）。装置生产运行工况的改变对蒸汽的使用与消耗会产生一定的影响。通过对不同工况条件下相关数据的采集和生产改造等因素的分析,尝试探寻出装置节能运行方向,并从管理、计量、操作等角度为建立更合理、优化、高效的蒸汽网络提出改善建议,以期使燕山乙烯装置蒸汽使用能效水平进一步提高。     

核电站厂区蒸汽管网凝结水排放研究

核电站内蒸汽用户分布在主厂区、三废区、水处理区等区域,通过蒸汽管网将汽轮机厂房或者辅助锅炉房的蒸汽输送至各个蒸汽用户。由于蒸汽管网与环境之间存在着巨大的温度差,蒸汽散热形成凝结水在管网低点集聚。本文对国内外核电站蒸汽管网布置以及凝结水排放的设计方案进行了调研,详细比较分析了每种方案的利弊,为后续核电站蒸汽管网凝结水排放的设计提供了参考。     

注蒸汽热采技术研究进展

在研究大量文献的基础上,总结了注蒸汽采油的机理,概述了稠油注蒸汽热采的研究现状与发展趋势,着重探讨了稀油注蒸汽热采的应用前景、研究现状以及稀油注蒸汽热采还需要深入研究的课题。研究认为：稠油注蒸汽热采已是比较成熟的技术,在稠油开发中占有重要的地位,其发展趋势为利用天然气、溶剂、高温泡沫、聚合物等来改善注蒸汽热采效果;稀油油藏水驱、聚驱后转注蒸汽热采具有可行性,今后需重点解决的问题包括采用煤或核能生产蒸汽、采用水汽交注、蒸汽泡沫等方法提高稀油油藏注蒸汽热采的采收率。     

蒸汽雾化式减温器探讨

通过蒸汽雾化式减温器的减温过程分析其质量和热量平衡,建立减温后的蒸汽流量和减温水流量公式,阐明影响减温水流量和减温后蒸汽温度的各种因素。针对蒸汽雾化式减温器的结构提出了减温水品质、雾化蒸汽压力、汽化长度、喷水调节阀、选型等使用要求。结合蒸汽雾化式减温器的优缺点,简要介绍了蒸汽雾化式减温器的应用现状。     

利用国产耐高温纤维开发蒸汽防护服装

分析了国内外蒸汽防护服装的研究现状,利用国产耐高温纤维,从蒸汽防护面料的开发、蒸汽防护服装的结构设计等方面进行了研究,并对蒸汽防护性能进行了测试。结果表明:开发的蒸汽防护面料和服装具有耐高温、防蒸汽渗透和隔热性能,能够满足安全防护需求。     

Steam flow law in horizontal wells when considering reservoir heterogeneity

Steam injection in horizontal wells for thermal recovery of heavy oil is a complex and changeable process. The prediction of thermal properties of steam along horizontal wells is critical to the uniform production of reservoirs. In this paper, considering the mutual coupling effects of reservoir permeability, confining pressure, and steam phase transition, a comprehensive mathematical model for predicting steam injection flow in horizontal wells was established. Compared with the on-site logging data, the accuracy of the model was verified. The simulation results show that under a single variable condition, the larger the steam injection pressure at the heel, the faster the mass flow and steam dryness decrease. When the steam injection pressure drops from 11 MPa to 8.5 MPa, the steam distribution distance doubles. At the same position, the higher the steam dryness at the heel, the greater the mass flow in the steam injection well, and the faster the steam pressure decrease. Double the steam injection dryness, the pressure drop is almost doubled, but the longer steam injection distance. The larger the steam injection flow at the heel, the faster the steam pressure decreases, and the decrease in the steam dryness in the tube slows down. When the steam injection flow increases by 1.75 times, the pressure drop increases by 5.3 times. The higher the reservoir permeability, the faster the steam dryness decreases. By obtaining the general rules of steam distribution in horizontal wells to provide theoretical support for on-site steam injection, the steam distribution effect can be effectively improved to increase production and reduce consumption.     

考虑储层非均质时注汽井内蒸汽流动规律

稠油热采水平井注蒸汽是一个复杂多变的过程,水平井沿程蒸汽热物性的预测对于储层的均匀动用十分关键。考虑储层渗透率、围压和蒸汽相变等条件的相互耦合影响,建立了预测水平井注汽流动的综合数学模型。与现场测井数据进行对比分析,验证了模型的准确度。模拟结果表明,单一变量条件下,水平井跟部注汽压力越大,注汽井内质量流量和蒸汽干度下降越快,当注汽压力由11 MPa降为8.5 MPa时,配汽距离增加1倍;在水平井相同位置处,跟部注汽干度越高,注汽井内质量流量越大,且蒸汽压力下降越快,注汽干度提高1倍时,压降也几乎增加1倍;跟部注汽流量越大,蒸汽压力下降越快,注汽流量提高1.75倍时压降提高了5.3倍,但管内蒸汽干度下降趋缓;储层渗透率越高,注汽井内的蒸汽干度下降越快。该模型可以为现场注汽提供理论支撑,有效提高配汽效果达到增产降耗。     

稠油井分层稳恒注汽技术

注蒸汽吸汽不均问题是稠油非均质油藏蒸汽吞吐开发主要矛盾之一,多年来工艺技术人员研究应用选配注技术,通过分隔纵向油层,实施配汽,取得了较好的效。但是不能同时给两个油层注汽,只能先注下层,然后投球配注上层,蒸汽的热损失大,而且存在人为误差和蒸汽的浪费,同时在热采井口投球存在不安全隐患。针对这类问题,研制应用了分层稳恒注汽技术,将分层稳恒注汽管柱下入指定位置。注汽时,蒸汽通过稳恒注汽阀按设计注汽量进入油层,达到调整和改善油层的吸汽剖面,使油井各层位产能达到均衡动用,提高热采效果和采收率。     

一种新型多喷嘴汽-液喷射器的性能

目前汽-液喷射技术中关于湿蒸汽的研究较少,然而在实际工业中,相当一部分低压蒸汽是具有一定干度的湿蒸汽。为此,设计了以湿蒸汽为工作蒸汽的实验台,并采用一种多喷嘴结构的汽-液喷射器作为实验元件,分析了蒸汽压力、蒸汽干度及喷射器背压对其性能的影响。实验结果表明：蒸汽干度使蒸汽质量流量随蒸汽压力变化的曲线平移。喷射系数随蒸汽干度的增大而增大。蒸汽压力较低时,喷射系数和过冷水流量随蒸汽压力的升高而增大,随着蒸汽压力的升高,当汽羽的长度大于喷射器的喉嘴距时,过冷水发生壅塞,喷射系数开始减小,而过冷水流量的减小延迟。总体上,喷射系数随背压的升高而减小,在背压不同的范围内,喷射系数下降的速度有所不同。     

低压蒸汽系统的蒸汽回收利用

针对低压蒸汽系统存在的问题,进行了低压蒸汽回收及低压蒸汽冷凝液系统的改造,改造后实现装置放空的低压蒸汽及低压蒸汽冷凝液的全部回收。     

差压式涡街质量流量计在蒸汽计量中的应用

鉴于稠油开采过程中的蒸汽吞吐及蒸汽驱技术,提出了对井口蒸汽质量流量计量的新方法。首先测量蒸汽通过涡街发生体后的差压,得到涡街频率,进而求出蒸汽的质量流量。这里主要介绍了用于蒸汽质量流量计量的压差式涡街流量计的原理,并对流量计的检测特点和实现的可行性进行了简单阐述。     

SUPERHEATED STEAM IMPINGEMENT DRYING OF TORTILLA CHIPS

ABSTRACT

Low-fat snack products are the driving forces for the drying of tortilla chips before frying. Super-heated steam impingement drying of foods has the advantage of improved energy efficiency and product quality. The temperature profile, drying curves, and the physical properties (shrinkage, crispiness, starch gelatinization and microstructure) of tortilla chips dried at different superheated steam temperatures and heat transfer coefficients were measured. Results indicated that the steam temperature had a greater effect on the drying curve than the heat transfer coefficient within the range of study. The microstructure of the samples after steam drying showed that higher steam temperature resulted in more pores and coarser appearance. The modulus of deformation and the shrinkage of tortilla chips correlated with moisture content. A higher steam temperature caused less shrinkage and a higher modulus of deformation. The pasting properties showed that samples dried under a higher steam temperature and a higher heat transfer coefficient gelatinized less during drying and had a higher ability to absorb water. Comparison of the superheated steam drying and air drying revealed that at elevated temperatures the superheated steam provided higher drying rates. Furthermore, there was a less starch gelatinization associated with air drying compared to superheated steam drying.     

Quality Changes of Superheated Steam–Dried Fibers from Oil Palm Empty Fruit Bunches

Conventional drying of the fibers from oil palm empty fruit bunches (EFB) using flue gas from diesel burners frequently causes browning and dust explosion. Replacing the drying medium with superheated steam is expected to improve the quality of EFB fibers as well as improve the safety of the dryer operation. In this study, the effects of steam temperature and steam velocity on the quality of steam–dried EFB fibers was investigated. The drying experiment was carried out at atmospheric pressure with steam superficial velocity in the range of 0.3 to 0.49 m s^?1 and temperature in the range of 135 to 200°C. Three quality parameters of the EFB fibers, the color, strength, and microstructure, were used to assess the changes in EFB fiber quality as a result of superheated steam drying. The color of the EFB fiber was either improved or not significantly degraded. The strength of the superheated steam–dried EFB fibers was higher than that of undried and hot air–dried EFB fibers. The microstructure of fresh undried EFB fibers as seen by scanning electron microscopy (SEM) showed the presence of round silica particles of 10–20 µm in diameter all over the EFB fiber strand, which complicates pulping and bleaching. Superheated steam drying successfully removed the silica particles from the EFB fibers at temperatures of at least 200°C and a velocity of steam of at most 0.49 m s^?1, which is better than hammering, which can only remove 88% of the silica particles. The high temperature of the superheated steam loosened the silica particles from their craters. The EFB fibers cracked and split at steam velocities at or above 0.49 m s^?1 and high superheated steam temperatures at or above 200°C and as a consequence became weaker at these conditions. The removal of silica particles by superheated steam drying makes the EFB fiber amenable to pulping and bleaching. Superheated steam drying is therefore found to improve the overall quality of EFB fibers compared to hot air drying.     

蒸汽—电联合动力在水泥厂余热利用中 的分析与实践

针对许多熟料生产线的剩余余热蒸汽,设计了蒸汽—电联合动力方式,通过工业汽轮机与电动机联轴运行,实施水泥厂大型转动设备的蒸汽—电联合动力。实现了以较低的成本,扩展水泥厂余热蒸汽的利用范围,降低熟料生产线的用电量。论文对比分析余热发电与蒸汽—电联合动力的效率,结果表明,蒸汽—电联合动力有更高的效费比,更低的投资与运行费用。