含动力学抑制剂的天然气水合物相平衡研究对新型低剂量抑制剂的开发具有指导作用。在283.6 ~ 290.9 K和7.51 MPa ~ 15.97 MPa的温压范围内研究了抑制剂Inhibex501及其溶剂2-乙二醇单丁醚对甲烷水合物相平衡条件的影响。实验结果显示，0.5wt%和2.0wt%浓度的Inhibex501对甲烷水合物形成的热力学条件具有促进作用，能使甲烷水合物形成移向更高的温度或者更低的压力，而2-乙二醇单丁醚在浓度0.2wt% ~ 1.0wt%范围几乎不改变甲烷水合物形成的热力学条件，N-乙烯基己内酰胺与N-乙烯基吡咯烷酮的共聚物对水合物形成热力学条件的改变起主要作用。
Investigation on equilibrium conditions of natural gas hydrates with low-dosage hydrate inhibitors (LDHIs) aqueous solutions is helpful for the development of LDHIs. In this work, experimental studies on the equilibrium conditions for methane hydrate formation were carried out with different concentrations of N-vinylcaprolactam- N-vinylpyrrolidone copolymer in 2-butoxyethanol (Inhibex501) under temperature range of 283.6 ~ 290.9 K and pressure range of 7.51 MPa ~ 15.97 MPa. Results showed that the formation of methane hydrate was promoted by Inhibex501 with concentration of 0.5wt% and 2.0wt%. The thermodynamic conditions of the formation was nearly unchanged with 2-butoxyethanol concentrations of 0.2wt% ~ 1.0wt%. The N-vinylcaprolactam- N-vinylpyrrolidone copolymer, as the main component of Inhibex501, played a leading role in the change of equilibrium condition of methane hydrates.
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