SU1454958A1 - Method of isolating subsoil water inflow into well - Google Patents

Abstract

The invention relates to an oil producing industry. The goal is to increase the effectiveness of the formation isolation. A water isolating material is pumped into the latter, which is used as a water-repellent material in oil with a concentration of 3-5%. Marshallite is hydrophobized by mixing it with oil with a density of 700-750 kg / m, followed by drying at 200-250 ° C and grinding to a powder. After injection of an insulating solution, an oil column with a density of 84–920 kg / m is left in the table to automatically replenish the bottom-hole zone. The well was commissioned not earlier than 24 hours. Te

Description

one

The invention relates to the oil industry, in particular, to methods for isolating the flow of formation water into oil and gas wells .5

The purpose of the invention is to increase the effectiveness of the formation isolation.

The method is carried out as follows.

Prepare a hydrophobic mart-10 scallite. Marshallite (sand powder, i.e. ground sand to powder) is poured with light oil or condensate with a density of 700-750 kg / m, then is thoroughly mixed until the dough is 15 and left for physicochemical interaction. . After that, the resulting mass is dried for 40-50 hours at 200-250 C. During the drying, the mass is mixed with;

the purpose of preventing it from sintering. The dried mass is ground, and then mixed with oil. The hydrophobised Marshallite prepared in this way is ready for use. Then, all necessary tests are carried out with a hydrophobised marshallite. Using studies to determine the optimal concentration in Marshallite oil, it is 5 wt.%. The solubility of hydrophobized marshallite in oil is then determined. These experiments elucidate the time when the marshallite precipitates and the precipitate completely stops precipitating. The precipitation from the solution completely stops after 24 hours, i.e. the pore blockage time of the precipitate (hydrobased marshallite) is 24 hours.

cl

with

SP 00

PRI me R. In the bilayer-cedor model using the proposed method, water was displaced from the highly permeable zone by oil and hydrophobic marshallton. As a result of hydrophobicization and blockage, the permeability of the model was 0.1-0.07 kg. km (prior to the experiment, the permeability of the model was 0.7-0, 8 kg-km), t, e, a blockage occurred, resulting in an additional 9-17% of oil (without taking into account the injected oil), indicating high efficiency proposed method.

The chosen range of concentrations of the dissolved hydrophobic marlusite in oil is explained as follows. If the concentration of marshallite is 2%, then practically no precipitate is formed, since the marshallmt is in a suspended state. At a concentration of 3% precipitation begins after 90 minutes, i.e. already with this concentration, the method is operational. From experience it is clear that the more. coitration of marshallt, the faster the precipitate appears and already starting with a concentration of 7% marshallite and up to 10% of the time the precipitation occurs at the same time of 5 mil. Therefore, it is advisable to limit the upper concentration range of marshallite to 6%. It has also been proven by experiments that after 24 hours (regardless of the concentration of marshallite in the oil), it will all precipitate, i.e. well can be explored.

To displace oil from the Nlast, it was displaced from the model by fresh water. Water was pumped through 7-10 pore volumes until the complete cessation of oil flow from the model. The oil displacement ratio was 45-47%. Then, a mixture of oil with a hydrophobised Marshallt was pumped into the model by 10% of the pore volume (the concentration of Marshallite in oil was 5 wt.%). Left for 24 hours. After that, on the other.

the sides of the model pumped fresh water and displaced the oil. The water pumped 2.0–2.5 volumes. Thus, due to the hydrophobization of the high-permeable zone, the final oil displacement ratio was 54-64%.

To implement the proposed method in practice, the following operations are necessary. In the bypass, the well is first pumped oil (density 840–920 kg / m), displaces the ruptured water deep into the reservoir to displace the ruptured

water from the bottomhole zone (R-2.5 m). The volume of oil injection is calculated using the formula hm, where R is the radius of the bottomhole zone, h is the bed height, and m is the porosity.

After oil injection, oil is pumped into the reservoir together with hydrophobised marshallite. The optimal concentration of marshallite is 5% by weight. After injection of isolating

the solution for the automatic execution of the bottomhole zone (in case of leaks) in the wellbore is left, an oil column with a density of 840 920 kg / m. The well is put into operation no earlier than 24 hours.

Thus, the proposed method allows a 2-3 times longer turnaround time.

Claims (1)

Invention Formula The method of isolating the inflow of formation water into the well by pumping a water insulating material into the formation, characterized in that, in order to increase the effectiveness of the formation isolation, as a water insulating material, a hydrophobic material is pumped into the reservoir at a concentration of 3-5%, and Marshallite is hydrophobized by mixing Marshallite with oil with a density of 700–750 kg / m, followed by drying at 200–250 ° C and grinding to a powder.