Study On Wax Deposition Regularity Of Gathering And Transportation Pipelines In Changqing Oilfield

It is difficult to manage gathering&transportation pipelines because of their complicate operating conditions.Based on the Chuanping 46-23 Gathering&Transportation Pipeline in Changqing Oilfield and its operating parameters,in this paper,the appropriate models,such as flow pattern model,liquid holdup calculation model,pressure drop calculation model and wax deposition model,were selected by comparative analysis.Then,the variation of operating pressure,temperature,liquid holdup,effective inner diameter,gas/liquid superficial velocity and wax deposition rate with pipe distance and operating time and the influence of flowrate,gas-oil ratio,moisture content etc.on wax deposition rate and other operation parameters was analyzed by programming and calculating the models.The wax deposition rate,pressure,temperature,liquid superficial velocity and liquid holdup reduces,gas superficial velocity increases with the increase of pipeline length;the wax deposition rate,temperature,gas/liquid superficial velocity increases,the pressure and liquid holdup decreases at the same node with the increase of operating time within 24 operating hours.The wax deposition rate,operating temperature and gas/liquid superficial velocity increases,operating pressure and liquid holdup reduces when the liquid flow rate increases.The gas superficial velocity increases,liquid holdup reduces and other parameters have a little change when the gas-oil ratio increases.The operating temperature increases,wax deposition rate and operating pressure reduces,the variation of gas superficial velocity of the whole pipeline is not consistent,the liquid holdup changes in the opposite to gas superficial velocity,and liquid superficial velocity changes little When the water content increases.The wax deposition rate,operating pressure and liquid holdup increases,gas superficial velocity reduces,operating temperature and liquid superficial velocity changes little when the inlet pressure increases.The wax deposition rate and operating temperature increases,the change of operating pressure,gas/liquid superficial velocity and liquid holdup is not consistent in different operating time when inlet temperature increases.The operating pressure,operating temperature and liquid holdup increases,wax deposition rate and gas/liquid superficial velocity reduces when environment temperature increases.