CN1313561C - Preparation process of inorganic filler type water-absorbing resin prepared by underground polymerization - Google Patents

Abstract

The invention relates to the preparation process of inorganic filler type water-absorbing resin prepared by underground polymerization in the technical field of polymer synthesis. The reaction raw materials are injected into the ground and then reacted at the formation temperature. The raw materials are composed of acrylamide monomer, acrylic acid monomer, Alkali, inorganic filler, cross-linking agent, initiator, auxiliary agent, wherein acrylamide is 1-10% of the total solution, acrylic acid 1-10%, cross-linking agent is 0.01-1% of the total solution, auxiliary agent is 0.01-1%, the inorganic filler is 1-10%, eliminating the need for above-ground polymerization, granulation, drying, screening and other processes. At the same time, the product prepared by the present invention can have greater plugging effect after the target formation is swollen with water, so it has a better effect for near-well water plugging and bottom water coning chemical partitions.

Description

Preparation process of inorganic filler type water-absorbing resin prepared by underground polymerization

technical field

The invention relates to the technical field of polymer synthesis, in particular to a preparation process for preparing inorganic filler type water-absorbing resin through underground polymerization.

Background technique

At present, the inorganic filler-containing water-absorbing resins used for water plugging and profile control in oilfields are all made in ground factory equipment. Due to the fast water absorption speed of the profile control agent, when it does not reach the target layer, it has already swelled and saturated, so it cannot A large plugging force is generated at the target layer, especially when water plugging and bottom water coning in the near wellbore area, the swelling plugging force of the body-expanding granular profile control agent produced on the ground is not enough. This patent proposes the method of polymerizing superabsorbent resin underground On the basis of adding inorganic fillers, it is beneficial to increase its service temperature, reduce costs and increase compressive strength.

Contents of the invention

The purpose of the present invention is to provide a preparation process for underground polymerization of inorganic filler type water-absorbent resin that can effectively solve the problem of bottom water coning in high-temperature water wells in oil fields, and is used to increase plugging force and improve compressive strength and temperature resistance range.

The present invention is achieved in this way: the preparation process of inorganic filler-containing water-absorbent resin refers to injecting the reaction raw materials into the ground and then reacting at the formation temperature. The raw materials are composed of: acrylamide monomer, acrylic acid monomer, alkali, inorganic filler , Cross-linking agent, initiator, auxiliary agent, etc.

Acrylamide is 1-10% of the total solution, acrylic acid is 1-10%, the alkali is 60-90% of the acrylic acid monomer, the crosslinking agent is 0.01-1% of the total solution, and the auxiliary agent is 0.01-1%. The inorganic filler is 1-10%, and the initiator is 0.02-0.09% of the total solution.

Described acrylic acid needs to be neutralized, wherein the alkali used for neutralization is sodium carbonate, sodium hydroxide, potassium hydroxide or potassium carbonate etc.; Initiator is ammonium persulfate, potassium persulfate, hydrogen peroxide, benzoyl peroxide or Azobisisobutylcyanide.

The crosslinking agent is aluminum citrate, polyhydric alcohol, glycerin, triethanolamine, N, N-methylene bisacrylic acid amine or N, N-dimethyl bisacrylic acid amine.

Its inorganic filler is bentonite, kaolin, clay or activated clay.

The auxiliary agent is EDTA disodium salt, EDTA tetrasodium salt, ferrous sulfate or potassium ferricyanide.

Mix the polymerizable acrylamide monomer, acrylic acid monomer and inorganic filler, auxiliary agent, redox initiator, reaction delay agent, etc. on the ground with an enamel stirring tank, and then pump it underground. It reacts at the formation temperature to form a super absorbent resin containing inorganic fillers, which can generate greater plugging force after absorbing water and expanding at the target layer of the formation.

The advantage of the present invention is that: the proposed underground polymerization method of the inorganic filler-containing water-absorbing resin saves the above-ground polymerization, granulation, drying, screening and other processes. At the same time, the product prepared by the present invention can have a large plugging effect after the target formation is swollen with water, so it has a good effect for near-well water plugging and bottom water coning chemical partitions.

Detailed ways

Example 1:

Add 200kg of acidic vinyl monomer to a neutralizing agent in an enamel stirred tank to generate acidic vinyl sodium salt, then add 800kg of 40% acrylamide, 18kg of cross-linking agent aluminum citrate, 9 tons of tap water or oilfield mineralized water, 400kg of bentonite, an appropriate amount of polymerization initiator ammonium persulfate 0.06% and auxiliary agent EDTA disodium salt 1%, after stirring evenly, pump into the formation, close the well and wait for solidification. After a period of time, open the well and inject water.

Example 2:

In a stirred tank, neutralize 200kg of acrylic acid with sodium hydroxide (60% of the mole of acrylic acid monomer), then add 300kg of 40% acrylamide, 400kg of kaolin, and 8.4 tons of mineralized water, stir evenly, and then add a crosslinking agent 2kg of polyol, appropriate amount of initiator azobisisobutylcyanide 0.09% and auxiliary agent ferrous sulfate 0.01%, stir evenly, then pump into the ground or mix in proportion and then continuously inject into formations that need water shutoff.

Example 3:

Neutralize 200kg of acrylic acid with 90% sodium carbonate of acrylic acid monomer to a neutralization degree of 90%, then add 625kg of 40% acrylamide, 300kg of activated clay, add 9 tons of mineralized water, stir evenly, and add an appropriate amount of cross-linking Agent N, N-dimethyl bisacrylic acid amine 0.08%, initiator hydrogen peroxide 0.02%, auxiliary agent potassium ferricyanide 0.05%, etc., and then construct the bottom water cone well.

Claims (3)

1. The preparation process of inorganic filler type high-rate water-absorbing resin prepared by underground polymerization is characterized in that: the reaction raw materials are injected into the ground and reacted at the formation temperature. The raw materials are composed of: acrylamide monomer, acrylic acid monomer, alkali, Use bentonite, kaolin, clay or activated clay as inorganic filler, EDTA disodium salt, EDTA tetrasodium salt, ferrous sulfate or potassium ferricyanide as additives, crosslinking agent, initiator, Among them, acrylamide is 1-10% of the total solution, acrylic acid is 1-10%, the alkali is 60-90% of the acrylic acid monomer, the crosslinking agent is 0.01-1% of the total solution, and the auxiliary agent is 0.01-1%. The inorganic filler is 1-10%, and the initiator is 0.02-0.09%. 2. The preparation process of inorganic filler type high-rate water-absorbing resin prepared by underground polymerization as claimed in claim 1, characterized in that: the acrylic acid needs to be neutralized, and the alkali used for neutralization is sodium carbonate, sodium hydroxide, hydroxide Potassium or potassium carbonate; initiators are ammonium persulfate, potassium persulfate, hydrogen peroxide, benzoyl peroxide or azobisisobutylcyanide. 3. The preparation process of inorganic filler type high-rate water-absorbing resin prepared by underground polymerization according to claim 1, characterized in that: the crosslinking agent is aluminum citrate, polyol, glycerin, triethanolamine, N,N- Methylenebisacrylate or N,N-dimethylbisacrylate.