A new in-depth fluid diverting agent of inorganic gel coating

The inorganic gel coating diverting agent, which is non-toxic and environmentally friendly, is developed for in-depth water diversion to improve water flooding effect. After being injected into the formation, the agent reacts with the formation water and forms inorganic silicate gel with a density approximating to formation water. The gel suspends in water as a bulk or particulates, scales and forms inorganic gel coating on rock surface by way of adsorption. The dominant channels of deep formation water are narrowed, forming flowing resistance and forcing flow diverting of the subsequent fluid so as to improve water flooding effect. This agent features fast solution, temperature resistance, salt resistance, environmentally friendly, and long-acting. It has been used in different reservoirs with different temperatures and salinity conditions, such as the Lunnan Oilfield of the Tarim Basin, the Yuejin oil region of the Qaidam Basin, and the Dagang Oilfield for in-depth flow profile control. The field applications involve single well group and whole block, with success ratio up to 100%, average injection pressure of well group increasing by 2–3 MPa, and the effective rate of oil production increase and water-cut decrease of producers are over 80%.