The invention relates to an expansion and solidification type plugging agent which comprises the following components in parts by weight: 0.5-2 parts of a
calcium sulphoaluminate expanding agent, 1-4 parts of
polypropylene fibers, 0.1-1 part of a water adsorption expansion type
polymer, 1-5 parts of
super absorbent resin SAP, 2-6 parts of puffed
starch, 2-6 parts of salt-resistant clay, 20-40 parts of
calcium carbonate and 0.1-0.5 part of high
viscosity polyanionic
cellulose PAC-HV. The preparation method comprises the following steps: sequentially adding the components in parts by weight to a kneading
machine by a conventional preparation method under normal
temperature and pressure; uniformly mixing and stirring; and crushing to a particle product with the grain size of 0.01-0.5mm till being dried. The plugging agent provided by the invention has the characteristics of high
expansion rate,
viscous flow capacity, plugging capacity,
strong salt-resistance, flowability, pumpability, good coagulability, simple process, safe and quick construction, long coagulability, wide source of raw materials, high plugging success rate and the like, and is widely applied to plugging processes of
large pore paths, subterranean rivers and great
Karst cave leakage strata in
petroleum and geological drilling.