Expansion and solidification type plugging agent

Abstract

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.

Description

technical field [0001] The invention relates to a drilling lost circulation agent, in particular to an expansion and consolidation type lost circulation agent. Background technique [0002] Diesel bentonite slurry is a common expansive plugging agent in oil drilling. Diesel bentonite slurry is mixed with diesel oil, bentonite, soda ash, lime, etc. in a certain proportion. When the mixture is pumped into the leakage layer and contacts with water, Suspended bentonite particles begin to hydrate and separate from the oil to form a tough lump of oil sludge, thereby achieving the purpose of plugging. This plugging agent has played a role in oil drilling, but it also has the following disadvantages or shortcomings: ① Seeing that the water expansion multiple is high, but it can be compressed after expansion, has no strength, and the validity period is short; ② Diesel bentonite slurry can expand, but No strength, no coagulation, large displacement circulation will be destroyed under...

AI Technical Summary

Problems solved by technology

This plugging agent has played a role in oil drilling, but it also has the following disadvantages or shortcomings: ① Seeing that the water expansion multiple is high, but it can be compressed after expansion, has no strength, and the validity period is short; ② Diesel bentonite slurry can expand, but No strength, no coagulation, large displacement circulation will be destroyed under the action of external force, ③Cross-linked polymer plugging agent has no coagulation, poor temperature and salt resistance, short validity period, can not be restored after being compressed, and is prone to accidents Repeated leakage, the effect is poor; ④ The compound application has a certain plugging effect in the construction of medium and small fractures and porous formations to deal with permeability loss, but the consumption of plugging materials is large, and the plugging time is long, which is easy to cause downhole complex Accidents; when encountering large-scale leakage, it cannot be solved; resulting in repeated leakage, resulting in great economic losses, directly affecting the plugging effect and drilling engineering