蓄能液气泡钻井液的制备

针对普通泡沫流体抗压能力弱的缺点,研究了蓄能液气泡的制备原理,并设计研制出了蓄能液气泡钻井液发生装置,其可提供在0.1~20 MPa不同压力下产生的蓄能液气泡钻井液。蓄能液气泡内部是黏膜包裹的独立内气核,外部是由表面活性包裹水分子构成的双层膜结构,平均粒径约为0.29 mm,累计体积分布最多的气泡直径在0.25~0.33mm之间。研究表明:与常规泡沫相比,蓄能液气泡表现出很强的抗压能力,例如成泡气核压力为0.5 MPa的蓄能液气泡,其直径随压力的增加而下降,当压力增加到5 MPa时气泡直径分布在0.29 mm左右,压力大于7 MPa后气泡体积不再发生较大变化,趋于稳定,而且仍然能够有效降低钻井液密度。蓄能液气泡钻井液是对泡沫流体认识的一次飞跃。

Preparation and Performance of Energized Foam Drilling Fluid

A device was designed to produce energized foam drilling fluid which can be used to replace conventional foam drilling fluids easily to be defoamed by pressure. The energized foam mud was formulated with energized foams made at high pressure being mixed with common drilling fluids, and was thus quite different from conventional foam muds. Study indicated that the energized foam mud produced by the device had (bubble) core pressures of 0.1-20 MPa, capable of withstanding higher pressure. In annular spaces with high pressures, this energized foam mud still maintained low density, and hence low static pressure on the bottom hole.