Method for treating the area surrounding a well using an aqueous gelling solution comprising an alkaline potassium silicate solution and an acetic acid

{
  "publication_number": "US11028310B2",
  "country": "US",
  "kind": "B2",
  "title": "Method for treating the area surrounding a well using an aqueous gelling solution comprising an alkaline potassium silicate solution and an acetic acid",
  "abstract": "The present invention relates to a process for the treatment of the area (10) surrounding a well (1) in which an aqueous gelling solution comprising an alkaline potassium silicate solution and an acetic acid is prepared and then injected into a subterranean formation. This aqueous gelling solution makes it possible, by virtue of these gelling properties, to block the area (10) surrounding the well (1).",
  "claims": [
    "1. A process for the treatment of the area surrounding a well within a subterranean formation, the well being for storage of acid gas in the subterranean formation, the process comprising: preparing an aqueous gelling solution comprising an alkaline potassium silicate solution and an acetic acid; and injecting the aqueous gelling solution from the well into the subterranean formation, in order to treat, within the subterranean formation, the area surrounding the well, wherein the acid gas is stored in the subterranean formation prior to injecting the aqueous gelling solution.",
    "2. The process as claimed in claim 1, wherein preparing the aqueous gelling solution further comprises measuring one or more of porosity, permeability and surrounding pH of the subterranean formation.",
    "3. The process as claimed in claim 1, wherein the prepared aqueous gelling solution has a viscosity of between 1 and 10 pct.",
    "4. The process as claimed in claim 1, wherein the prepared aqueous gelling solution has a setting time of between 3 and 20 hours.",
    "5. The process as claimed in claim 1, wherein the acetic acid has a concentration of between 0.1 and 5 mol/l.",
    "6. The process as claimed in claim 1, wherein the alkaline potassium silicate solution comprises a concentration of silicon Si of 0.5 to 7 mol/l.",
    "7. The process as claimed in claim 1, in which the alkaline potassium silicate solution comprises a molar ratio of silicon dioxide SiO 2 with respect to the potassium oxide K 2 O of between 0.5 and 10.",
    "8. The process as claimed in claim 1, wherein the aqueous gelling solution comprises between 1% and 30% by weight of acetic acid.",
    "9. The process as claimed in claim 1, further comprising injecting a flushing fluid from the well into the subterranean formation prior to injecting the aqueous gelling solution.",
    "10. The process as claimed in claim 1, further comprising plugging the well after injecting the aqueous gelling solution.",
    "11. The process as claimed in claim 1, wherein the acetic acid has a concentration of between 0.5 and 2 mol/l.",
    "12. The process as claimed in claim 1, wherein the alkaline potassium silicate solution comprises a concentration of silicon Si of 0.5 to 3 mol/l.",
    "13. The process as claimed in claim 1, in which the alkaline potassium silicate solution comprises a molar ratio of silicon dioxide SiO 2 with respect to the potassium oxide K 2 O of between 1 and 5.",
    "14. The process as claimed in claim 1, wherein the aqueous gelling solution comprises between 5% and 30% by weight of acetic acid.",
    "15. A process for treatment of an area surrounding a well in a subterranean formation that stores acid gas, the process comprising: preparing an aqueous gelling solution by combining components comprising an alkaline potassium silicate solution and acetic acid; and injecting the aqueous gelling solution through the well and into the subterranean formation that stores the acid gas, the aqueous gelling solution treating the area surrounding the well in the subterranean formation."
  ],
  "description_excerpt": "The present invention relates to the field of the treatment of the area surrounding a well within a subterranean formation, in particular for a well for the geological storage of acid gases, for example carbon dioxide CO 2. In particular, the invention relates to the closing of wells giving access to geological formations in which the storage takes place by injection. One of the objectives is to prevent leakages, in particular of acid gases, for example of CO 2, via the well or its vicinity.\n\nProcedures for the shutdown of wells are known in which plugs of different qualities are introduced into the casings of the well: mechanical plugs made of expandable material, cement plugs, resin plugs. However, the durability of these materials, and also that of the casing pipe subjected to corrosion, are not sufficient in the case of the storage of acid gases, in particular of CO 2.\n\nInjections under pressure (squeeze) of specific blocking products via the perforations of the well, in order to seal off the porous and permeable formation, are also known. However, it is known that it is difficult to control the placing of these injected products, which renders the efficiency of the blocking uncertain.\n\nIn addition, the patent application WO 2010/0107219 A1, which describes a method for the treatment of the area surrounding a well for the storage of acid gas, is known. For this method, a flushing fluid and then a reactive solution suitable for reacting with acid gases are injected into the rock, this reactive solution comprising basic oxides.",
  "cpc": [
    "C09K 8/426",
    "C04B 28/26",
    "C09K 8/44",
    "C09K 8/506",
    "C09K 8/508",
    "E21B 33/138",
    "E21B 41/0064",
    "Y02C 20/40"
  ],
  "ipc": [
    "C09K 8/42",
    "C09K 8/44",
    "E21B 33/138"
  ],
  "assignees": [
    "IFP Energies Nouvelles IFPEN"
  ],
  "inventors": [
    "Olivier Sissmann",
    "Marc Fleury",
    "Michel Chardin"
  ],
  "filing_date": "2017-02-15",
  "publication_date": "2021-06-08",
  "grant_date": "2021-06-08",
  "priority_date": "2016-04-04",
  "application_number": "US-201716090858-A",
  "family_id": "56148472",
  "cited_by_count": 1,
  "citations": [
    "US4215001A",
    "US4438976A",
    "US5067416A",
    "US20080028995A1",
    "US20140352967A1",
    "WO2014190226A1"
  ]
}