The invention relates to a PS [PAM-Ca-LS (
polyacrylamide-
calcium lignin sulfonate)]
lignin gel type profile control agent. By the aid of the PS
lignin gel type profile control agent, the problem of poor profile control effects due to high initial
viscosity, short profile control valid periods and low plugging efficiency of existing profile control agents mainly can be solved. The PS lignin gel type profile control agent is characterized by comprising, by weight, 0.5-1.5% of macromolecular polymers, 1-10% of gel, 0.2-2.0% of
colloid stabilizers, 0.2-2.0% of reducing agents, 0.2-0.6% of chelating agents, 0-1.0% of retarders, 0.5-1.5% of cross-linking agents and the
balance water. A method for preparing the PS lignin gel type profile control agent includes adding the corresponding water into a container, then sequentially adding the gel, the
colloid stabilizers, the reducing agents and the chelating agents into the container, circularly stirring the corresponding water, the gel, the
colloid stabilizers, the reducing agents and the chelating agents at the normal temperature under the normal pressure for half an hour to obtain first mixtures, then spreading the macromolecular polymers into the first mixtures, stirring the macromolecular polymers and the first mixtures for 2 hours to obtain second mixtures and allowing the second mixtures to stand still for 8 hours to obtain agents A; completely dissolving the cross-linking agents and the corresponding water according to a proportion of 1:1 to obtain agents B; adding the retarders into the agents A before the agents B are injected, adding the agents B into the agents A and uniformly stirring the agents A, the retarders and the agents B to obtain the PS lignin gel type profile control agent. The PS lignin gel type profile control agent and the method have the advantages of long profile control valid period, high plugging efficiency and good profile
control effect.