天然气水含量与水露点关联换算

借助天然气水含量与水露点关联关系可将在线测定的水含量换算为工况条件下的水露点值,以此判定天然气是否满足GB 17820对水露点的要求.使用GB/T 22634-2008得到的水露点与冷镜面法露点仪实际测量的水露点值是一致的,Z值均小于1.96.而其他方法与冷镜面法露点仪实际测量的水露点相比,在多数情况下Z值都大于1.96,且Z值随压力的升高而增大,证明GB/T 22634-2008更适用于长输管道天然气水含量与水露点的换算,更能真实反映现场管输天然气的水露点情况.     

天然气中水含量与水露点换算关系探讨

目的采用实验加数学拟合的方法开发一种新型天然气中水含量与水露点的换算方法,以提高换算精度并降低误差。 方法综合应用气体标准物质、便携式冷镜仪以及数学软件Matlab,采用三次样条插值技术建立了一种新型水含量与水露点换算方法。 结果利用三次样条插值技术建立拟合曲面方法进行水露点换算,该方法的平均绝对误差(MAE)为1.16 ℃,均方根误差(RMSE)为2.28 ℃,满足合理可接受的最大偏差为2.8 ℃。将该方法与国内外主流的换算方法进行比较分析,3种方法的平均绝对偏差分别为0.46%(三次样条插值法)、0.69%(GB/T 22634-2008《天然气水含量与水露点之间的换算》)和0.84%(ASTM D1142-95(2021)《露点温度法测定气体燃烧水蒸气含量的标准试验方法》),并分析探究了3种方法在不同水含量和压力段的适用情况。 结论通过与实验值的对比研究,当水的体积分数在0~200×10-6范围内时,三次样条插值法相比标准方法具有更好的换算精度,可有效降低水含量与水露点的换算误差。      

天然气在线水含量/水露点换算仪设计与试验

天然气的水含量和水露点指标对于天然气的管道运输和生产装置的正常运行非常重要,但是目前现场所使用的在线水含量/水露点分析仪内置软件对于这两个指标的换算结果与真实值之间的偏差很大。为了解决此问题,设计开发了基于OPC通信的在线天然气水含量/水露点换算仪。经过试验证明该换算仪可以实时在线运行,具有很好的换算精度和换算效率。     

中国、ISO和俄罗斯天然气水露点测定标准方法比对

水露点是天然气质量控制和管道安全运行的重要指标,也是进口俄罗斯天然气技术协议谈判中重点关注的指标。对中国、ISO和俄罗斯三方的天然气水露点测定标准方法开展了详细的比对,首先是标准文本的比对,其次是采用标准水露点发生器生成的气源,在实验室开展比对,最后是依据中国和俄罗斯两国标准,分别采用两国常用的水露点分析仪,在两国标准规定的不同吹扫条件下,在输气站现场开展了比对。通过比对,明确了三方标准最大的区别是吹扫方式;在无干扰情况下,中国和俄罗斯常用水露点分析仪检测结果准确可靠且相互吻合良好;在存在干扰情况下(可能是醇类或烃类),中国和俄罗斯常用水露点分析仪检测结果差异较大,最大差值达到6.1℃。比对结果为进口俄罗斯天然气技术谈判提供了支撑。     

外输煤制天然气水露点的确定

煤制天然气是我国能源领域的新兴产业,煤制天然气的制取及脱水干燥、外输等是煤制天然气项目的重要组成部分,如何确定经济、合理的外输煤制天然气水露点,以保证煤制天然气项目的长期经济运行及长输管道的安全运行。本文根据辽宁大唐国际阜新煤制天然气项目及该项目的长输管道和下游用户等实际工况,结合了标准规范对外输天然气水露点的规定,分析讨论了影响煤制天然气水露点的因素及规律,确定了该项目经济、合理的外输煤制天然气水露点。     

气田外输天然气水露点确定研讨

气田开发、外输管道、下游利用工程是组成天然气工程项目的三大部分，如何合理确定气田外输天然气的水露点以保证外输管道的安全运行、用户对气质的要求，是涉及到气田天然气处理方案的制定、外输管道的配套设计运行的综合性优化问题。结合克拉2气田向西气东输管道及下游用户的供气分析，阐明了天然气水露点确定需要考虑的因素，并提出了相关建议。     

天然气中水含量分析方法标准简介

目前,测定天然气中水含量有两类方法,一类是仪器方法,包括用冷却同凝析湿度计测定天然气水露点和用电解式水含量分析仪直接测定天然气水含量;另一类是化学方法,包括卡尔费休法、五氧化二磷吸收法和比色法等。本文主要就相应的ＩＳＯ国际标准介绍了后一类垢原理、适用范围、准确度和精密度、测定流程及步骤等内容,并提出了采标建议。     

天然气液化系统露点的定量分析

在天然气液化系统中,水露点凝结而成的液滴会造成相关设备发生露点腐蚀,而烃露点凝结而成的液滴不会导致设备发生露点腐蚀,反而可以抑制露点腐蚀的发生。为找到天然气水露点和烃露点的临界点,采用Aspen Plus软件建立了天然气露点定量分析模型,对天然气液化系统中的轻组分天然气和含有微量重组分天然气的露点进行了定量分析,同时分析了天然气压力以及天然气中CO₂物质的量分数对露点的影响。结果表明,轻组分天然气的露点类型为水露点,会对天然气液化系统相关设备造成露点腐蚀;天然气中微量的C₆重组分不会对露点温度及露点溶液组成造成影响,而微量的C₇、C₈和C₉重组分则会改变露点温度及露点溶液组成。可通过向天然气中增添微量C₉及C₁₀₊重组分来预防天然气液化系统相关设备发生露点腐蚀。     

对商品天然气烃露点指标的认识

液烃在管道内冷凝会产生两相流而影响管输计量的准确性,并加大管道阻力,造成极大安全隐患,同时也会影响燃气透平的操作,对压缩机组的运行造成不良影响。因此,要求天然气输配系统必须保证在高于管输天然气烃露点的条件下运行。那么规定合理的烃露点指标并准确地进行测定就显得尤为重要。为此,讨论了测定商品天然气烃露点的两种方法--冷却镜面法和气相色谱法,认为后者才是当前发展的方向;并指出商品天然气烃露点指标仅取决于管道的操作条件及运行环境,且只有建立了准确的测定方法后才有可能确定。     

Evolving ANFIS model to estimate sweet natural gas water content

Water existence in natural gas may cause difficulties in processing facilities and also transmission through pipelines. Therefore, it will be important to find a way to estimate water content values. An intelligent learning Adaptive Network-based Fuzzy Inference System (ANFIS) is introduced to estimate water content under a given temperature and pressure condition. Assessment of model's accuracy is carried out by determining mean relative error as 4.08% and R-squared value as 0.9996. Statistical analyses indicate the brilliant predictive ability of suggested ANFIS model. In addition, a comparison of our model's outcomes with other existence correlations also confirmed its satisfactory predictions.     

Utilization of LSSVM strategy to predict water content of sweet natural gas

The presence of water in the natural gas causes numerous operating problems. Hence, in order to have satisfactory operational conditions in the gas production units, we should determine the accurate amount of water content of natural gas. This study aimed to develop a low parameter predictive tool based on the least square support vector machine for estimating water content of natural gas as a function of temperature and pressure under a wide range of conditions. Results obtained from the suggested model indicated its lower deviation than other existence correlations and confirmed its acceptable predictive capability. In addition, the obtained values of R-squared and mean relative error were 1.00 and 0.24%, respectively. This tool is simple to use and can be of help to gas engineers to determine an accurate approximation of water content of natural gas.     

Estimating water content of natural gas: A radial basis function neural network method

Association of water with natural gas streams can highly affect processing and transmission of natural gas. Therefore, the water content of the natural gas must be known in order to determine best possible processing and transmission conditions. This study aims to develop a simple predictive approach to predict water content of sweet gas in wide pressure and temperature ranges, using a radial basis function artificial neural network. The proposed model shows lower deviation from experimental data compared to existing empirical correlation. R-squared and mean relative error values are 0.998% and 4.07%, respectively.     

Estimation of natural gases water content using adaptive neuro-fuzzy inference system

To appropriate design and satisfactory performance of utilities in the gas processing and transmission plants, a crucial factor that should be taken in consideration is the natural gas water content. The present research aimed to develop a precise strategy for estimating sour gas/sweet gas water content ratio. This developed predictive tool is based on adaptive neuro-fuzzy inference system (ANFIS). In this regard, a comprehensive data bank that contains 1,126 data points was collected. This model predicts ratio of sour gas to sweet gas as function of pressure, temperature, and equilibrium H₂S mole fraction. The ranges of pressure and temperature were 200–70000 KPa and 10–150°C, respectively. In addition, the equilibrium H2S mole fraction ranges between 0.076 and 0.492. Results obtained from the ANFIS model confirmed acceptable and reasonable predictive capability of this model. This tool is simple to use and can be help petroleum engineers to predict water content of natural gas at broad ranges of conditions.     

天然气含尘量检测装置

针对常用天然气除尘方法存在的问题 ,利用湍球塔式水浴除尘原理研制出了一套检测精度较高的橇装式天然气含尘量检测装置。该装置按照“等速等压”原则进行取样与测试 ,待检测天然气通过装有湍动球的水浴除尘器 ,使气流充分分散、润湿 ,从而使粉尘以污水形式保留在除尘器内。对污水干燥、称量 ,即可得到测试天然气的含尘率 ,同时亦可利用不同渗滤直径的膜对粉尘进行分级。川东气田现场测试证明 ,装置原理正确 ,性能稳定 ,工作可靠 ,可用于对现有除尘设备进行检测和评价     

确定一段蒸汽转化转化气量/天然气量比值的方法

根据物料平衡关系导出由天然气中的二氧化碳及转化气中的一氧化碳和二氧化碳所决定的天然气一段蒸汽转化的转化气量/天然气量之值,并据此介绍了蒸汽分解率的简单计算方法。     

Estimation of water content of natural gases using particle swarm optimization method

A precise estimation of natural gas water content is a significant constraint in appropriate planning of natural gas production, processing services and transmission. The main contribution of this research is to develop a machine learning approach for predicting water content of sweet and sour natural gases. In this regard, a joining of particle swarm optimization and an artificial neural network was utilized. The suggested model presents good predictions of the sour natural gas water content with following circumstances, including CO₂ contents of 0–40 mol%, H₂S contents of 0–50 mol%, pressures in range from atmospheric to 70,000 KPa for sour gas and 100,000 KPa for sweet gas, and temperatures from 10–200°C for sweet gases and 10–150°C for sour gases.     

节能型天然气一段转化催化剂放大研究

对放大制备的自行开发的节能型天然气一段转化催化剂进行了表征和评价。结果表明,与现有工业催化剂相比,低水碳比工况下,该催化剂活性相当,但抗积炭性能更好。     

天然气发电机的气体处理装置研制

为了利用油田的伴生气资源,在采油站推广应用了天然气发电机.由于伴生天然气中含有水、轻质油、固相颗粒等杂质,对天然气发电机有损害,需利用天然气处理装置对其进行净化和干燥,也有利于稳定供给.文章介绍了该装置的工艺流程、设计参数和现场应用情况.