Acid polymerization of spent sulfite liquor derived solids, polymerized reaction products formed thereby, and compositions utilizing same

Claim 1

A DRILLING MUD COMPOSITION COMPRISING A SUSPENSION OF A CLAYEY MATERIAL IN AN AQUEOUS MEDIUM CONTAINING AN EFFECTIVE DISPERSING AMOUNT OF AN ADDITIVE COMPRISING AN ACID POLYMERIZED, WATER-SOLUBLE, SULFONATED LIGNIN-CONTAINING MATERIAL HAVING A RELATIVE VISCOSITY IN 10% AQUEOUS SOLUTION OF ABOUT 1.4-4.0, SAID ADDITIVE HAVING BEEN PREPARED BY A PROCESS COMPRISING MIXING A SOLUTION OF SULFONATED LIGNIN-CONTTAINING MATERIAL WITH AN ACIDIC REAGENT, WHICH REAGENT FORMS WATER-INSOLUBLE SALTS WITH CALCIUM, TO GIVE A REACTION SOLUTION HAVING A PH OF LESS THAN ABOUT 4.0, THE CONCENTRATION OF SULFONATED LIGNINCONTAINING MATERIAL IN THE REACTION SOLUTION BEING BETWEEN ABOUT 10% AND ABOUT 70%, HEATING THE ACIDULATED MIXTURE AT A TEMPERATURE OF AT LEAST ABOUT 50*C. FOR A SUFFICIENT TIME TO CAUSE POLYMERIZATION OF THE CONTAINED LIGNOSULFONIC ACID TO THE POINT WHERE THE RELATIVE VISCOSITY OF AN AQUEOUS SOLUTION CONTAINING 10% BY WEIGHT OF THE REACTION PRODUCT SOLIDS INCREASES TO ABOUT 1.4-4.0, AND INTERRUPTING THE REACTION WHEN SUCH RELATIVE VISCOSITY IS REACHED.