关键词: 油砂, 石英砂, 天然气水合物, 耗气量

Abstract:

When crude oil is extracted from oil wells, associated gas will be generated, and natural gas hydrates will be generated in high pressure and low temperature environments, which will block the transportation pipeline. Therefore, it is of great significance to study the hydrate formation in oil sand system (that is, the crude oil?containing system) and the pure quartz sand system (not including crude oil). The formation of methane hydrate and the final gas consumption in the oil sand system) and the pure quartz sand system were studied under the conditions of initial pressure of 4.00, 6.00, 8.00 MPa, quartz sand particle size of 20, 30, 60, 80 mesh, and constant temperature.The results show that in the oil sand system and under the same initial pressure conditions, the smaller the particle size of quartz sand, the shorter the induction period for hydrate formation, and the greater the rate of hydrate formation; the effect of particle size on the final gas consumption for hydrate formation It is found that as the particle size of the quartz sand decreases, the gas consumption first increases and then decreases. When the particle size of the quartz sand is 60 mesh, the gas consumption reaches the maximum, and its value is 0.19 mol. At the same time, the hydrate formation in the oil sand system and the pure quartz sand system was compared. The results show that, due to the presence of SDS (sodium dodecyl sulfate) solutions in the two systems, there is little difference in the formation rate of hydrates; the final gas consumption in the oil sand system is less than that in the quartz sand system under the same quartz sand particle size. This indicates that crude oil has an inhibitory effect on the formation of hydrates. In the oil sand system, it is found that the higher the pressure, the more favorable the formation of hydrates.

Key words: Oil sand, Quartz sand, Natural gas hydrate, Gas consumption