不同温度下空气中饱和水分含量及饱和蒸汽压

《不同温度下空气中饱和水分含量及饱和蒸汽压》由会员分享，可在线阅读，更多相关《不同温度下空气中饱和水分含量及饱和蒸汽压（14页珍藏版）》请在装配图网上搜索。

1、不同温度下空气中饱和水分含量及饱和蒸汽压兰州真空设备有限责任公司温度。C饱和水分含量 g/m3饱和蒸汽压Pa温度C饱和水分含量 g/m3饱和蒸汽压Pa4050.917368.624-121.81217.38243846.006618.708-141.52181.28523641.515935.392-161.27150.78243437.405314.68-181.06125.07483233.644483.512-200.888103.36323030.304238.42-220.73685.2482827.203776.22-240.59070.06322624.303357.972-26

2、0.50457.2762421.802981.016-280.41446.75322219.402641.356-300.34038.09522017.302336.33-320.27730.76921815.362061.936-340.22624.90841613.631815.516-360.18420.11321412.051597.068-380.14916.11721210.681401.264-400.12012.9204109.351226.77-420.09610.256488.281072.26-440.0778.125267.28933.732-460.0616.3936

3、46.39812.52-480.0495.061625.60704.628-500.0383.862804.85609.923-520.0303.0636-24.14516.816-540.0242.3976-43.52436.896-560.0181.8648-63.00368.298-580.0141.4652-82.54309.8232-600.0111.0656-102.14259.74-900.0093粘滞流下20C空气的管道流导真空设计手册项目公 式长管1.34 X103 d 4 pU =l短管111=+ UU U短孔管矩形截面 直管4560K a2b2 -U =/ Pa/ b1.

4、00.90.80.70.60.50.40.30.20.1K f1.000.990.980.950.900.820.710.580.420.23环形管道U =丝 P X d - d -(d1 - d2)2 l12ln(d1 / d 2)椭圆管道42920 a 3b3U =pla 2 + b 2孔当 1 x 0.525 时，U = 76.6x0.712 xj 1 - x0.228 _A- 1 - x曰200A当 x 0.525 时， U =01 - x当 x 100.400.520.600.670.941环形12.1K (d d )2 x (d + d ) a 1212d2/d100.2590.5

5、0.7070.8660.966lKa11.0721.1541.2541.4301.675椭圆形TT136.6a 2 b 21U = = x a 2 + b 2l锥形d 2 d 2U = 24.2M (d + d )l直角弯管，4， 按直管计算,管道计算长度l = l1 +12 + 3 d缩孔TT9.11d 2 d 2U = 12-d2 d2符号：U一流导（L/s）a和b椭圆长半轴、短半轴l管长（cm）a面积（cm2）d管道直径（cm）材料物理性能组别牌号重度 g/cm3膨胀系数 dX106导热系数 卡/厘米.秒.度电阻系数Q .mm2/m熔点C纯铜T18.920 C17.70.961083T2

6、8.917.70.951080T48.8917.40.431080黄铜H908.818.20.40.039H808.6519.10.340.054H658.4720.10.2880.069H628.4320.60.260.071纯铝20100C20200CL62.712424.80.54658L42.712424.80.52LY112.82223.40.41铸铝ZL22.810.230.240.330.354.664.926ZL52.580.2450.2550.218.21ZL102.650.190.210.385.275.57ZL142.70.220.230.350.455.886.67碳钢

7、10钢7.8511.60.8080.13245钢7.8111.590.5020.132不锈 钢1Cr18Ni97.90.0390.0420.1630.731Cr18Ni9Ti7.750.0390.0420.1630.73GB 5832.2-86气体中微量水分的测定-露点法1适用范围本标准适用于氧、氮、氢、氦、氖、氩、氟、氙、二氧化碳等气体中微量水分露点的测定。其测量范围0C-70C。2原理2.1术语说明水分露点一一在恒定的压力下，气体中的水蒸气达到饱和时的温度。2.2方法原理本法用露点仪进行测定。使被测气体在恒定压力下，以一定的流量流经露点仪溅定室中的抛光金属镜面。该镜面的温度可人为地降低并可

8、精确 地测量。当气体中的水蒸气随着镜面温度的逐渐降低而达到饱和时，镜面上开始出现露，此时所测量到的镜面温度即为露 点。（由露点和气体中水分含量的换算式或查表，即可得到气体中微量水分含量。）3仪器3.1概述仪器可以用不同的方法设计，主要的不同在于金属镜面的性质、用于冷却镜面的方法、如何控制镜面的温度、测定温 度的方法以及检测出露的方法。镜子和它的附件通常安放在气体样品流经的测定室中。3.2仪器的一般要求提供下述装置、满足基本要求的任何露点仪都可以使用。3.2.1当仪器温度高于气体中水分露点至少2C时，可以控制气体进出仪器的流量。3.2. 2把流动的样品气冷到足够低的温度，使得水蒸气能凝结，冷却的

9、速度可调。3.2.3能观察露的出现和准确地测量露点。3.2.4气路系统死体积小且气密性好，露点室内气压应接近大气压力。3.2.5用标准样衡量仪器是否符合要求，按GB 4471-84化工产品试验方法精密度室间试验重复性和再现性的确定 第4.3条进行。3.3目视和光电露点仪简单的露点仪以手动调节冷量，控制镜面降温速度，用目视法观察露的生成。该法凭经验操作，人为误差较大。采用 光电系统确定露生成的光电露点仪有相当高的准确度和精密度；用户按需要和可能进行选择。3.4露的观察目视露点仪用肉眼观察露的出现。光电露点仪是采用装在测定室的光源照射镜面，光源和光电池能以各种方式排列， 当镜面未结露时，无散射发生

10、，硅光电池上没有光照，镜面上结露后，入射光在镜面发生散射，一部分光照射到硅光电池上 从而产生光生电压，给出出露信号。3.5 镜面制冷方法用下述方法来降低和调节镜子温度，其中3.5.1和3.5.2所介绍的方法要求操作人员注意观察而不适用于自动装置。 对自动装置，使用两种方法制冷：3.5.3和3.5.4所介绍的液化气体制冷及热电效应制冷。3.5.1溶剂蒸发制冷用一种挥发性液体与镜子背面接触，用通入低压空气或其他压缩气体鼓泡的办法使液体气化而制冷。3.5.2绝热膨胀法制冷让一种气体通过喷嘴后流过镜子背面，由于气体发生膨胀而使镜面冷却，这种气体通常用钢瓶装压缩二氯化碳，也可 以使用压缩空气和压缩氮气等

11、。本法至少能使镜面温度下降40C。3.5.3 液化气体制冷目前广泛使用液化气体作冷却剂。如用液氮可获得-80C或更低的温度。当用液化气体制冷时，可以使和镜子背面相接 触的铜棒与液化气体直接接触、或通过电热方法使液化气体气化来制冷，也可以使压缩气体通过液氮浸泡着的盘管冷却后制 冷。3.5.4用热电（珀尔帖）效应制冷该法也就是半导体制冷，采用多级串联获得不同的低温。3.6温度测量应尽可能准确地测量出露时镜面的温度，为了避免镜面上的温度差异，应使用高热导性的镜子，一般采用金、铜、不 锈钢和铑合金。测量露点温度，使用精密水银温度计、热电偶、热敏电阻或伯电阻感温元件。目前，高精度测量都采用伯电阻感温元

12、件。4分析前的准备4.1试漏测试系统所有接头处应无泄漏，否则会由于空气中水分的渗入而使测量结果偏高。简单的试漏方法如下：将盛有水的u型压力计接在仪器的气体出口处，调节气路压力，使u型管内压差为lOOOmmH），关闭气源，经5min水 柱下降不超过5mm，说明系统气密性良好。必要时，应升高压力试漏。若发现系统漏气，则应分段检查解决。4.2取样设备4.2.1取样阀：用死体积小的调节阀，如针形阀。4.2.2取样管：原则上采用尽可能短的小口径管子，一般使用长度不超过2m，内径不大于4mm的不锈钢管或壁厚不小 于1mm的聚四氟乙烯管，使用前洗净，再吹干或烘干。不允许用橡皮管。4.2.3取样阀的吹洗徽开取

13、样阀，开启钢瓶顶阀后立刻关闭。开大取样阀待放出的气流变小时关小取样阀，再开启钢瓶顶阀后立刻关闭， 如此反复三次，再进行测定。4.2.4流量计的标定应针对不同气样，用皂膜流量计标定样品气的测试流量。5 一般操作步骤5.1用气体吹洗管道和测定室。对放置后刚启用的仪器，当待测气体中水分露点约为-60C时，应吹洗2h后才能进行 测定。5.2调节样品气流量至规定范围内。5.3开始制冷，当镜面温度离露点约5C时，降温速度应不超过5C/min，对不知道露点范圈的样品气，可先进行一次 粗测。5.4停机后，样品气的进出口拧上密封螺母。6注意事项6.1干扰物质6.1.1概述当固体颗粒或灰尘等进入仪器并附着在镜面上

14、时，用光电法测得的露点值将偏离I除水蒸气外的其他蒸气也可能在镜 面上冷凝，使得所观察到的露点不同于相应的水蒸气含量的露点。6.1.2固体杂质及油污如果固体杂质绝对不溶于水，它们就不会改变露点，但是会妨碍出露的观察。在自动装置中，对固体杂质如果没有采 用补偿装置，在低露点测量时，有时会因镜面上附着固体杂质使测得的露点值偏高，这时应该用脱脂棉蘸上无水乙醇或四氯 化碳清洗镜面。为了防止固体杂质的干扰，仪器入口要设置过滤器，而过滤器对气体中水分应无吸附。如果被测气体中有油污，在气体进入测定室前应该除去。6.1.3以蒸气形式存在的杂质烃能在镜面上冷凝，如果烃类露点低于水蒸气露点，不会影响测定。在相反的情

15、况下，会先于水蒸气而结露，因此水 蒸气冷凝前必须分离出烃的冷凝物。如果被测气体中含有甲醇，它将与水一起在镜面上凝结，。这时得到的是甲醇和水的共同露点。6.2冷壁效应除镜子外，仪器其余部分和管道的温度应高于气体中水分露点至少2C，否则，水蒸气将在最冷点凝结，改变了气体 样品中水分含量。6.3降温速度如果气体样品中水分含量较低，冷却镜子时应尽可能的慢。因为这时冰的结晶过程比较缓慢，若以不适当的速度降 温，在冰层生长和达到稳定之前，还没有观察到出露，温度巳大大超过了露点，这就是过冷现象。通常肉眼能观察到的露大约是10-5 g/cm2，用灵敏的光电露点仪，可检测出很低的水分含量。用目视露点仪测定较低的

16、水分含量时，应采取下述措施ta. 接近露点时，冷却镜子的速度应尽可能慢。b. 使用放大镜观察露的出现。c. 当镜子温度慢慢地降低，露刚出现时测得的温度与镜子温度慢慢上升而露消失时测得的温度之平均值作为露点。7结果处理7.1两次露点测定结果的算术平均值为露点值，两次露点溯定结果之差应小于第8章中对重复性的规定。7.2露点换算为ppm（V/V）按附录A （补充件）中A.1计算或查表。7.3露点换算为绝对湿度g/m3（20C，101.3kPa下）按附录A（补充件）中A.2计算或查表。8精密度露点低于-42C时方法的精密度：重复性 r=-0.93+0.041m再现性 R=3.67+0.019m式中：m

17、测定结果的平均值。重复性和再现性的应用按GB 4471-84第4章中有关规定执行。9报告报告应包括下列内容：a. 分析日期、室温、大气压b. 取样地点、编号、容器内压力c. 样品名称d. 分析结果：水分在样品气中的浓度e. 测定时观察到的任何异常现象f. 该标准中未包括的即自己选择的其他操作g. 分析员姓名附录A(补充件)本附录给出了气体中水分露点-ppm(v/v )换算及露点一绝对湿度(s/m3)换算的式子和结果。A.1露点换算为ppm按下式计算。, (Ap式中：P出露温度下冰的饱和蒸气压*，Pa。计算结果见表A1。A.2露点换算为g/m3(20C, 101.3kPa下)按下式计算。_F_x

18、_1810i_x 27293.110L322.41式中：p出露温度下冰的饱和蒸气压*, Pa。计算结果见表A2。表A1露点-ppm换算表露点，C0.00.10.20.30.40.50.60.70.80.9ppm露点，CO6033598359345885583757895741569456475600-15554550854635418537253285283524051965153-25111506850264983494249004860481947794738-34699465946214581454345054467442943924355-44318428142464209417441

19、744104406940354000-53965393238983865383238003767373437033671-63640360835773547351634863456342633973367-73339330932083253322431963169314131143087-83060303430072980295539292903287828522827-92803277827532730270626812658263526112588-1O2566254325202498247624542432241123892367-1123462326230522842264224422

20、24220321842165-122145212521072088206920502032201419951977-131960194219241906188918731855183818211805-141789177217561740172517091693167716611647-151632161716011587157315581543152915151501-161487147314601446143214201406139313801367-17135413421381317130512921280126912571245-1812331221120911981187117611

21、65115411431132-191121111111001090107910691059104810381029-20101910091000990.1981.O971.6962.3953.O943.9934.3-21925.9916.9908.1899.389O.6882.O873.4.865.1856.7848.4-22840.2832.O823.9815.9807.9800.1792.3784.6776.9769.3-23761.8754.3747.O739.6732.4725.2718.1711.0703.9697.0-24690.2683.4676.6670.O663.4656.8

22、650.2643.8637.4631.1-25624.9618.7612.4606.4600.3594.4588.5582.5576.7570.9-26565.3559.5553.9548.4542.8537.4532.O526.7521.3516.1-27510.9505.7500.6495.6490.5485.5480.6475.7470.9466.0-28461.3456.7452.O447.4442.8438.3433.8429.3425.O420.6-29416.3412.O407.8403.6399.4395.3391.2387.2383.2379.3-30375.3371.536

23、7.6363.8360.O356.3352.5348.9345.2341.7-31338.1334.6331.1327.5324.2320.7317.4314.1310.8307.5-32304.2301.1297.9294.8291.6288.5285.5282.5279.5276.5-33273.6270.7267.8265.0262.2259.3256.6253.9251.1218.5-34245.8243.1240.6238.0235.4232.9230.4227.9225.5223.O-35220.6218.3255.9213.5211.3209.O206.7204.4202.320

24、0.O-36197.8195.8193.6191.5189.3187.4185.3183.2181.2179.3-37177.3175.3173.4171.S169.6167.7165.9164.1162.3160.5-38158.7157.O155.2153.5151.7150.0148.4146.8145.1143.5-39142.0140.4138.8137.2135.6134.2132.7131.2129.7128.2-40126.8125.4124.0122.5121.1119.8118.5117.1115.8114.5-41113.1111.8110.6109.4108.1106.

25、9105.6104.4103.3102.1-42100.999.7098.6597.5296.4095.2994.2093.1192.O890.98-4389.9388.8887.8686.8485.8384.8583.8682.8881.9280.97-4480.0379.0978.1777.2776.3675.4774.5873.7172.8471.99-4571.1570.3169.4968.6767.8667.0666.2765.4864.7163.94-4663.1962.4461.7060.9760.2459.5358.8258.1157.4256.73-4756.O555.395

26、4.7254.0753.4252.7752.1451.5250.9050.29-4849.6749.O848.4947.9047.3246.7546.1845.6245.O644.52-4943.9843.4542.9142.3941.8841.3640.8640.3639.8639.38-5038.8938.4137.9437.4737.0136.5536.1135.6635.2234.79-5134.3533.9333.5033.O932.6932.2731.8831.4831.O930.69-5230.3229.9329.5629.1928.8328.4628.1027.7527.402

27、7.O6-5326.7126.3826.0525.7225.3925.0724.7524.4424.1323.82-5423.5123.2222.9322.6422.3422.0521.7821.5021.2220.95-5520.6820.419.0.1619.8919.6319.3919.1318.8818.6418.40-5618.1617.9317.7017.4617.2417.0216.7916.5716.3616.14-5715.9315.7315.5115.3115.1114.9214.7214.5314.3314.15-5813.9613.7713.5913.4213.2413

28、.O612.8912.7112.5512.38-5912.2112.O511.8911.7411.5811.4211.2711.1210.9710.82-6010.6810.5310.3810.2510.119.9809.8469.7139.5819.452-619.3249.1979.O728.9498.8278.7078.5888.4718.3558.241-628.1288.O177.9077.7997.6927.5867.4827.3797.2777.177-637.0776.9796.8836.7886.6946.6016.5096.4196.3306.241-646.1546.O6

29、85.9835.8995.8175.7355.6555.5765.4985.421-655.3455.2696.1945.121.5.O484.9774.9074.8374.7694.701-664.6354.5694.5034.4394.3764.3144.2524.1924.1314.O72-674.0143.9563.8993.8433.7883.7333.6793.6263.5743.522-683.4713.4213.3713.3223.2733.2263.1793.1323.0873.041-692.9972.9542.9102.8682.8252.7842.7432.7032.6

30、622.624-702.5842.5472.5092.4722.4352.3992.3632.3292.2932.260-712.2262.1922.1552.1272.0962.O642.0342.0031.9721.943-721.9141.8851.8571.8281.8011.7741.7461.7211.6941.668-731.6431.6181.5931.5691.5451.5211.4991.4761.4531.430-741.4091.3871.3651.3451.3241.3031.2831.2841.2441.224-751.2051.1871.1691.1501.132

31、1.1151.0981.0801.O631.O46-761.O311.0140.9980.98290.96740.95220.93720.92240.90790.8935-770.87940.86540.85170.83820.82500.81180.79890.78620.77360.7613-780.74920.73710.72540.71370.70230.69100.68000.66900.65820.6476-790.63710.62690.61670.60670.59690.58730.57770.56830.55900.5500-800.54100.53220.52350.514

32、90.50650.49820.49000.48190.47400.4662-810.45850.451O0.44350.43620.42900.42190.41490.40810.40130.3946-820.38810.38150.37520.36900.36280.35680.35070.34490.33910.3334-830.32780.32230.31690.31150.30620.30110.29600.29090.28610.2811-840.27640.37170.26710.26250.25800.25360.24940.2480.2480.2367-850.23270.22

33、860.22470.22080.21710.21330.20600.20600.20250.1989-860.19550.19210.18870.18550.18220.17910.17590.17290.16980.1668-870.16400.16110.15820.15550.15270.15000.14740.14480.14230.1397-880.13720.13470.13240.1000.12770.12550.12320.12100.11890.1167-890.11460.11260.11060.10860.10860.10470.10290.10100.O99110.09

34、739-900.095640.093900.092200.090520.O88880.O87270.O85680.O84120.082590.08108-910.079600.O78130.076700.075300.O73910.072560.O71220.O69910.O68620.06735-920.O66110.O64890.O63680.062500.061340.O60200.059080.O57990.056900.O5583-930.05480.O53770.052760.051780.O50800.O49850.O48910.047990.047090.04620-940.0

35、45320.044470.043620.042800.O41980.041100.040400.039630.O38880.O3814-950.067410.036690.035990.035300.034630.O33970.033310.O32670.O32040.O3142-960.030820.060220.O29630.O290B0.O28500.027950.O27400.O26870.O26350.O2583-970.O25S30.O24830.O2430.O23870.O23410.O22910.O22490.O22050.O21620.O2118-980.O20770.O20

36、360.O19960.019570.019170.O19170.O18800.O18420.017090.01734-990.01699O.016650.O16320.015990.O15680.O15360.O15050.O14750.O14450.O1416-1000.O1387表A2露点-绝对湿度换算表露 点，。C0.O0.10.20.30.40.50.60.70.80.9ppm露点，C-O4.5174.4804.4434.4074.3714.3354.2994.2644.2284.194-14.1594.1254.0914.O574.0233.9903.9563.9243.8913.8

37、59-23.8273.7953.7633.7323.7003.6693.6393.6093.5793.548-33.5193.4893.4603.4313.4023.3743.3453.3173.2893.261-43.2333.2063.1793.1523.1253.O993.0733.O473.O212.995-52.9692.9442.9192.8942.8702.8452.8212.7962.7732.749-62.7252.7022.6792.6562.6332.61O2.5882.5662.5442.521-72.5002.4782.4562.4362.4142.3942.3732

38、.3522.3312.312-82.2922.2722.2522.2322.2122.1932.1742.1552.1362.117-92.O992.O802.O622.0442.0262.0081.9911.9731.9551.938-1O1.9211.9041.8871.8701.8541.8381.8211.8051.7891.773-111.7571.7421.7261.7111.6951.6801.6651.6501.6351.621-121.6061.5921.5771.5631.5491.5351.5211.5081.4941.481-131.4671.4541.4411.427

39、1.4151.4021.3891.3761.3641.351-141.3391.3271.3151.3031.2911.2801.2681.2561.2441.233-151.2221.2111.1991.1891.1781.1661.1551.1451.1351.124-161.1131.1031.O931.O831.0731.O631.O531.0431.O331.024-171.O141. 850.99570.98610.97720.96760.95880.94990.941O0.9321-180.92330.91440.90550.89740.88850.88040.87230.864

40、10.85600.8479-190.83970.83160.82350.81610.80800.8060.79320.78500.77760.7703-200.76290.75550.74880.74140.73460.72750.72060.71360.70680.7000-210.69330.68660.68000.67340.66690.66050.65410.64780.64150.6353-220.62910.62300.61690.611O0.60500.59910.59330.58750.58180.5761-230.57040.56480.55940.55380.54840.5

41、4300.53770.5324O.52710.5220-240.51690.51180.50670.50170.49670.49180.48690.48210.47730.4726-250.46790.46330.45860.45410.44950.44510.44060.43620.43180.4275-260.42330.41900.41480.41060.40650.40240.39840.39440.39040.3865-270.38250.37870.37490.37110.36730.36350.35980.35620.35260.3490-280.34540.34200.3385

42、0.33500.33160.32820.32480.32150.31820.3150-290.31170.30850.30540.30220.29910.29600.29290.28990.28700.2840-300.281O0.27820.27530.27240.26960.26680.26400.26120.25850.2558-310.25320.25050.24790.24530.24280.24020.23770.23520.23270.2303-320.22780.22550.22310.22070.21840.21610.21380.21160.20930.2071-330.2

43、0490.20270.20050.19840.19630.19420.19210.19010.18810.1861-340.18410.18210.18010.17820.17630.17440.17250.17070.16880.1670-350.16520.16340.16170.15990.15820.15650.15480.15310.15150.1498-360.14810.14660.14500.14340.14180.14180.13870.13720.13570.1342-370.13280.13130.12990.12840.12700.12560.12430.12290.1

44、2150.1202-380.11890.11750.11620.11490.11360.11240.11110.10990.10870.1075-390.10630.10510.10390.10280.10160.10050.099350.098240.O97130.O9602-400.O94910.093880.092840.091740.0907 00.O89740.088710.087670.O86710.O8575-410.084710.083750.O82790.O81900.O80940.080060.O791O0.O78210.O77320.07643-420.O75550.O7

45、4660.O73870.O73030.0721 80.071360.O70540.069720.068920.06813-430.067340.O66560.065790.065030.O64270.O63540.062800.062060.061350.O6063-440.O59930.059230.O58540.O57860.057180.056510.O56510.O55200.O54550.O5391-450.O53270.O52650.052030.051420.O50810.O50210.049620.O49030.O48460.04788-460.O47320.046760.O4

46、6200.O45650.045110.044570.O44040.O43520.O43000.O4248-470.041970.O41480.040970.O40490.O400 00.039520.039050.O38580.O38110.03766-480.O37200.O36750.O36310.035870.O35440.O35010.O34580.034160.033740.O3334-490.O32930.O32530.032130.031740.O31360.O30970.O30600.O30220.029850.02949-500.O29120.028760.O28410.O2

47、8060.027710.027370.027040.026700.O26380.O2605-510.O25720.025410.O25090.O24780.O24480.O24160.O23870.O23570.O23280.O2298-520.O22700.O22410.O22130.021860.021580.O21310.O21050.O20780.O20520.O2026-530.O20000.O19750.019510.O19260.019010.018780.O18530.018300.O18070.01784-540.O17610.O17390.O17170.O16950.O16730.O16510.O16310.O161O0.O15890.O1569-550.015490.O15290.015090.O14900.0147 00.O14520.O14330.O14140.O13960.01378-560.013600.O13420.013250.013080.012910.O12740.012570.O12410.