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Then why is there no change at all in the temperature and pressure at the outlet? Is it exactly at the saturated liquid state right now?

Top pressure 67 kPa, outlet pressure gauge 65 kPa

1. Basically, the pipeline isn’t cold; it’s at room temperature, so there’s no sensation. 2. It cannot be said to be complete condensation either; if there is some non-condensable gas, it still needs to be vented through that pipeline.

Why are the pressure and temperature variations during import and export so small? Also, the bypass control valve of my heat exchanger shows no response when it is fully opened or fully closed – why is that?

Could you explain it in more detail? I didn’t understand\ud83d\ude4f

This post was last edited by HEJIYUER on 2020-2-4 at 18:23, version 1. Is the heat exchanger a plate heat exchanger? What are the inlet/outlet temperatures of the cooled water? 2. The vast majority of the exports are liquids, which can be considered fully condensed. (It is a gas; otherwise, the bypass TV valve will reheat the liquid, causing water hammer.) ) 3. The differential pressure of the bypass TV is only a few KPa; no matter how much it is increased, the flow rate Q cannot be adjusted. 4. If the return tank is used for water separation, then the non-condensable gas is steam. Can the non-condensable gas from the heat exchanger be sent to the return tank for subcooling? 5. The TV valve can lead directly to the gas phase space of the reflux tank; a PIC can be used to maintain the pressure in the reflux tank, thereby saving nitrogen and reducing material emissions. N2 can generate pressure, and hot toluene gas can also generate pressure. Why must N2 be used?

I suspect that the fluid coming out of the heat exchanger is in liquid phase; the bypass valve doesn’t respond because very little flow is passing through. This small amount of gas phase mixes with the liquid phase at the outlet, and although heating occurs, the mixture remains in a state close to saturated liquid. The pipes are large enough to prevent liquid slugging, and the pressure in the return tank is controlled using a proportional control system!

This post was last edited by HEJIYUER on 2020-2-4 at 18:35. The output should be a liquid, with the latent heat being used to cool the water. See my revision on floor 9. Table of saturated temperature and pressure for toluene. 5: Toluene: V/L sat. T=103.0 to 130.0 °C Liquid Vapor Liquid Vapor Temperature Pressure Density Density Enthalpy Enthalpy (C) (kPa) (kg/m^3) (kg/m^3) (kJ/kg) (kJ/kg) 1 103.00 81.248 786.89 2.4796 -15.118 350.52 2 104.00 83.695 785.88 2.5495 -13.141 351.85 3 105.00 86.199 784.86 2.6208 -11.159 353.19 4 106.00 88.762 783.85 2.6937 -9.1735 354.53 5 107.00 91.385 782.83 2.7682 -7.1843 355.87 6 108.00 94.069 781.80 2.8444 -5.1912 357.21 7 109.00 96.814 780.78 2.9221 -3.1943 358.55 8 110.00 99.622 779.76 3.0015 -1.1936 359.90 9 111.00 102.49 778.73 3.0825 0.81088 361.24 10 112.00 105.43 777.70 3.1653 2.8192 362.59 11 113.00 108.43 776.67 3.2498 4.8314 363.94 12 114.00 111.50 775.64 3.3361 6.8475 365.30 13 115.00 114.64 774.60 3.4241 8.8673 366.65 14 116.00 117.84 773.57 3.5140 10.891 368.01 15 117.00 121.12 772.53 3.6056 12.919 369.37 16 118.00 124.46 771.49 3.6992 14.950 370.73 17 119.00 127.88 770.44 3.7946 16.985 372.09 18 120.00 131.37 769.40 3.8920 19.025 373.46 19 121.00 134.93 768.35 3.9912 21.068 374.82 20 122.00 138.57 767.30 4.0925 23.115 376.19 21 123.00 142.28 766.25 4.1958 25.166 377.56 22 124.00 146.08 765.20 4.3010 27.220 378.93 23 125.00 149.95 764.14 4.4084 29.279 380.31 24 126.00 153.89 763.09 4.5178 31.342 381.68 25 127.00 157.92 762.03 4.6293 33.408 383.06 26 128.00 162.03 760.97 4.7430 35.479 384.44 27 129.00 166.23 759.90 4.8588 37.553 385.81 28 130.00 170.50 758.83 4.9769 39.632 387.20

Thank you\ud83d\ude4f