Being the mud cake formation for the excavation mud water, and the mud water null poly acrylic acid chloride

摘要

PROBLEM TO BE SOLVED: To form a drilling mud of only materials present in the drilling site dispensing with mud-forming materials such as bentonite, CMC, a polymer agent or the like.;SOLUTION: The mud film-forming agent for drilling mud comprises a single polymer comprising a (co)polymer (x') consisting essentially of an unsaturated carboxylic acid and/or a salt (a) thereof and the single polymer has a weight-average molecular weight Mw of 200,000-3,000,000. The reason why the weight-average molecular weight Mw of the single polymer is set to 200,000-3,000,000 is that the amount of filtered water as the index of the wall-forming property is slightly over 5 ml when the weight-average molecular weight Mw is lower than 200,000, whereas the amount of filtered water is far beyond 5 ml when the weight-average molecular weight Mw is higher than 3,000,000.;COPYRIGHT: (C)2005,JPO&NCIPI