Structure Development And Performance Research On Combined Hydro-cyclones And Coalescer

Film entrainment and breaking are important problems for centrifuga l clones. In order tosolve these problems and obtained a compact separator with high efficiency and lowresistance, this paper aimed to develop a Combined Hydro-cyclones and coalescer used atoffshore platforms for gas-liquid separation of natural gas.In order to select and optimize the type of hydro-cyclones used on CombinedHydro-cyclones and coalescer, multi-tube separator with reverse flow cyclones and differentstructural parameters of axial flow cyclones were used in the resistance characteristics andgas-liquid separation experiment. NaCl solution and air was used as medium. Someexperiments also achieved to study the effect of air exhaust on multi-tube separator with axialflow cyclones and some law of pressure drop and efficiency were obtained. The resultsshowed that, compared with multi-tube separator with reverse flow cyclones，multi-tubeseparator with axial flow cyclones with high efficiency and low resistance has betteroperation flexibility and more suitable to air-liquid separation。 For reference blade type andwith the same flow rate, outlet blade angle of45°has better efficiency than outlet bladeangle of30°when liquid load is higher than some point. Air exhaust can help increase theefficiency at low liquid load aero, but it lead to liquid film entrainment at high liquid loadaero and as a result the efficiency is decreased and lower than without air exhaust. Comparedwith multi-tube separator with axial flow cyclones of reference blade, the efficiency ofmulti-tube separator with rotating-stream trays is higher at the middle liquid load aero，butwhen the liquid load is extremely low or high, it has worse efficiency.The result shows that the axial force and tangential force on the liquid film are the keyreasons of film entrainment in axial flow cyclone. The tangential force mainly determines therate of the film and axial force determines the thickness of the film, and the product of themdetermines the Renault number of liquid membrane which determines the film entrainment. In order to compare the different combinations of hydro-cyclones and coalescertheoretical calculation and experiments are combined to study the efficiency of differentcombinations of mesh pad and multi-tube separator. The result show that the mesh pad inexhaust room contribute little to the pressure drop of the multi-tube separator while itcontribute a lot when the mesh pad are in the exhaust tube. Both combinations can improvethe separate ability of the separator on droplet which smaller than10μm, the big mesh pad inexhaust roo m contributes little to the separator. The main separate bases of the mesh pad inexhaust roo m are interception and diffusion, the main separate basis of the mesh pad inexhaust tube is inertial impaction.In order to provide data reference for engineering application some mode l selectionanalysis are provide about the multi-tube separator. Best cyclone tube can be selected on thebasis of conditions which include in the experiment range. Some simple scale-up studies onair-liquid separator are provided which give some analysis and prediction on pressure drop,flow rate and efficiency.