气体组成对钻井液中水合物形成动力学影响

深水钻井中,极易在钻井液中生成天然气水合物,给深水钻井带来极大的危害。气体组成不同,形成水合物的条件也不相同,给深水钻井中水合物的防治带来较大的困难。利用研发的钻井液中天然气水合物形成抑制试验装置,研究了3种不同组成的气体在2种水基钻井液中形成天然气水合物的动力学过程。研究表明,在实验的3种气体中,绿峡谷气最易形成水合物,简单混合气次之,而甲烷气体最难形成水合物;相同条件下,同种气体在不同的钻井液中水合物生成具有明显的差异,因此必须对钻井液体系相平衡条件进行测试,并优选有效的水合物抑制剂。对于烷烃来说,分子量越大,越易于生成天然气水合物。

Effect of Gas Composition on the Formation of Gas Hydrates in Drilling Fluid

Gas hydrates are easy to form in deep-water drilling, imposing great dangers to the drilling operation. Conditions under which gas hydrates are formed vary with gas composition, making it difficult to prevent the formation of gas hydrates. Using a newly developed device, the kinetics of the formation of natural gas hydrates in two water base drilling fluids is studied. Of the three gas compositions, the "Green canyon gas" forms gas hydrates in drilling fluid most easily, methane is the most difficult forming gas hydrates, with the simple gas mixture in between. With other conditions being the same, it is much easier for alkane of higher molecular weight to form gas hydrate in drilling fluids.