model gives for the vapour at kg, where Z(pR,TR)=0.87 has mV=VVV=pVV/(ZRT)=0.052 been found using with and For the pR=p50/pcr=0.5/3.8=0.13 TR=T50/Tcr=323/425=0.76. liquid density, the dilatable liquid model yields kg/m3. The best available data (NIST) gives, for K, kPa, T=323 pv=494.8 kg/m3 kg/m3, i.e. of liquid and of vapour. L=542.3 Comments. Typical commercial butane in Spain has 56% n-butane, 25% propane, 17% iso-butane, 2% pentane, 0,1 g/kg H2O and 1 mg/kg mercaptans, with ºC, kg/m3 at and kPa. L=580 pv()=520 The traditional butane bottle (Fig. 1) is made from 3.2± steel plate (two halves welded in the middle, with a welded collar and screwed valve on the top, and a welded standing ring at the bottom). All bottles are check for resistance with water at 3 MPa, and for air-tightness at 0.8 MPa, and a sample from the lot suffers a hydraulic end test to check that it breaks at >8.5 MPa. Fig. 1. Domestic butane bottle UD-125, with pressure regulator K30 (30 mbar). Fig. 2. Details of the collar, valve and regulator (K30) in a domestic butane bottle.
model gives for the vapour at mV=VVV=pVV/(ZRT)=0.052 kg, where Z(pR,TR)=0.87 has been found using with pR=p50/pcr=0.5/3.8=0.13 and TR=T50/Tcr=323/425=0.76. For the liquid density, the dilatable liquid model yields kg/m3. The best available data (NIST) gives, for T=323 K, pv=494.8 kPa, L=542.3 kg/m3 kg/m3, i.e. of liquid and of vapour. Comments. Typical commercial butane in Spain has 56% n-butane, 25% propane, 17% iso-butane, 2% pentane, 0,1 g/kg H2O and 1 mg/kg mercaptans, with ºC, L=580 kg/m3 at and pv()=520 kPa. The traditional butane bottle (Fig. 1) is made from 3.2± steel plate (two halves welded in the middle, with a welded collar and screwed valve on the top, and a welded standing ring at the bottom). All bottles are check for resistance with water at 3 MPa, and for air-tightness at 0.8 MPa, and a sample from the lot suffers a hydraulic end test to check that it breaks at >8.5 MPa. Fig. 1. Domestic butane bottle UD-125, with pressure regulator K30 (30 mbar). Fig. 2. Details of the collar, valve and regulator (K30) in a domestic butane bottle.
Exercise2.docx