防止深水钻井地层水合物分解的实验研究

利用水合物抑制与分解评价模拟实验装置,研究了搅拌条件、膨润土、钻井液添加剂以及水合物抑制剂对气体水合物形成的影响规律,考察了水合物的分解规律。结果表明,搅拌和膨润土的存在可加速水合物的形成,多数钻井液处理剂对水合物形成有一定抑制作用;改变水合物的存在条件(温度、压力)可引起水合物的分解;单一的热力学抑制剂可使水合物立即分解;而使用动力学和热力学抑制剂复配的深水钻井液既可防止天然气形成水合物,又可适当延缓水合物的分解时间,减少水合物分解造成的井喷。

Experimental Research on Prevention of Hydrate Decomposition in Deepwater Drilling Formation

The paper studied the influencing regulation of agitation condition,bentonite content,drilling fluid,additives and hydrate inhibitor on the formation of gas hydrates by means of experimental and evaluation devices for the inhibition and decomposition of hydrates and investigated the decomposition regulation of hydrates.It showed that the existence of agitation and bentonite could accelerate the formation of hydrates,but most of drilling fluid additives was of a certain extent of inhibition;the hydrates could be decomposed if the existence conditions(temperature and pressure) were changed;the hydrate would be decomposed immediately in contact with the unitary thermodynamic inhibitor,but a deepwater drilling fluid with both kinetic and thermodynamic inhibitors could not only prevent the formation of hydrates but also prolong the decomposition time in some extent so as to decrease the blowout caused by hydrate decomposition.