Abstract: A composition for acid gas absorbent comprising:(A): 99.99 to 70 wt % of a polyethylene glycol dimethyl ether composition represented by the following formula:CH.sub.3 O(C.sub.2 H.sub.4 O).sub.n CH.sub.3wherein n is an integer of 1 to 10; and,(B): 0.01 to 30 wt % of a compound containing at least one of an --NH-- group, a phenolic --OH group and an --S-- group in one molecule thereof but free from an alcoholic --OH group, is provided. More particularly, component B may be an amine, preferably a secondary amine, or a phenolic compound.

Abstract: Method to remove acid components from a gas including to absorb those with an organic absorbent based on ethers of polyglycols at an elevated pressure followed by regeneration of the saturated absorbent and by dehydration of a part of the regenerated absorbent by heating, which is characterized in that the dehydration of the absorbent is carried out by the combination of stripping with a gas and heating at the temperature lower than the boiling point at 0.8 to 1.3 atm. by 80.degree. to 150.degree. C.

Abstract: A method for plugging the areas of lost circulation occurred during the drilling of a well with the use of a drilling mud, and a lost circulation material to be used therefor. The lost circulation material comprising 1 to 90 parts by weight of a water-soluble solvent containing no active hydrogen atoms and hardly miscible with mineral oils and 10 to 99 parts by weight of a hydrophlic urethane prepolymer, and the method comprises injecting through the drilling pipe the lost circulation material sandwiched by a spacer of mineral oils, so as to allow the lost circulation material to penetrate into the lost circulation areas, to react with water which is present at the areas, and to plug the areas through its polymerization.