文档介绍：College of Chemistry & Chemical Engineering,SWPU1Southwest Petroleum University4 Water-Hydrocarbon SystemsWater Content of Natural GasWater-Hydrocarbon Phase EquilibriaGas HydratesThe Prevention of HydratesNew Methods of Hydrate PreventionCollege of Chemistry & Chemical Engineering,SWPU2Southwest Petroleum Water Content of Natural Gas一、基本概念自储集层中采出的天然气及脱硫后的天然气中,一般都含有水气(饱和水、游离水)。天然气水含量:在一定T、p下,天然气中所含有的饱和水蒸气量。游离水:天然气中以液相形式存在的水。天然气水露点:在一定p下,天然气中的气态水开始冷凝结露的温度。绝对含水量:单位体积天然气中的水气量,mg/m3。College of Chemistry & Chemical Engineering,SWPU3Southwest Petroleum Water Content of Natural Gas二、天然气含水量的测定1、取样原则?所取气样要有代表性;?取样管线上不能含游离水;?气体在取样管线内,应保持在露点温度之上;?取样管线应尽可能短,以缩短取样时间并防止水蒸气冷凝;?若系统中有过滤器,气样应流动5min,以在含水量测定前让水饱和过滤器。College of Chemistry & Chemical Engineering,SWPU4Southwest Petroleum Water Content of Natural Gas2、测定方法计量学原理:绝对方法和相对方法。测定方式:化学分析法和仪器测定法。College of Chemistry & Chemical Engineering,SWPU5Southwest Petroleum Water Content of Natural Gas二、天然气含水量的估算?算图估算:利用图来查取天然气的水含量。?公式法:利用生产过程中总结的经验公式计算。?状态方程法:进行精确的多组分平衡计算求取。1、算图估算(1)非酸性天然气含水量估算根据温度、压力以及天然气性质由露点图查得,常用的是Mcketta-Wehe算图,如下图所示。College of Chemistry & Chemical Engineering,SWPU6Southwest Petroleum Water Content of Natural Gas水含量校正:当天然气相对密度≠,且与盐水接触时水含量为:W=W0×CG×CS相对密度、?含量与纯水接触时的气体水含量与盐水接触时的气体水?SCCollege of Chemistry & Chemical Engineering,SWPU7Southwest Petroleum Water Content of Natural Gas(2)酸性天然气含水量估算当天然气中酸性组分(CO2、H2S)含量>5%,需要对含水量进行必要的校正。①Campbell法坎贝尔(Campbell)公式:W=yHCWHC+yH2SWH2S+yCO2WCO2基于纯酸气与水相平衡。WH2S纯H2S气体的含水量,WCO2纯CO2气体的含水量,分别由下图得到。College of Chemistry & Chemical Engineering,SWPU8Southwest Petroleum Water Content of Natural GasH2S的有效含水量CO2的有效含水量College of Chemistry & Chemical Engineering,SWPU9Southwest Petroleum Water Content of Natural Gas②、Wichert辅助算图一种新提出来的算图,如右图。A、首先将CO2的量折算成H2S的量。,得H2S的当量浓度。College of Chemistry & Chemical Engineering,SWPU10Southw