Oil reservoir protection accelerator and preparation method thereof

Abstract

The invention discloses an oil reservoir protection accelerator and a preparation method of the oil reservoir protection accelerator. The oil reservoir protection accelerator comprises the following components in percentage by weight: 0.1-1.0 percent of polyepichlorohydrin-dimethylamine, 0.5-2.0 percent of ammonium chloride, 0.1-0.5 percent of a surfactant, 5-15 percent of ethanol, and the balance of water. The oil reservoir protection accelerator is relatively-high in anti-swelling rate and anti-scouring degree, and can reduce the surface tension of working solutions and increase the filtration capacity of the working solutions; the water sensitivity and water blocking damages of a reservoir are greatly reduced, the aim that the protective reservoir is prevented from being damaged due to invasion of the working solutions is fulfilled, and the requirement of oil reservoir protection in a construction operation process of low-porosity and low-permeability reservoirs is met. The oil reservoir protection accelerator can be used in various measure working solutions in an oil field production process, can also be used as an addictive of the measure working solutions such as acidification, crushing, water plugging and profile control, and has functions of protecting stratum and preventing the stratum from being damaged in an operation process.

Description

technical field [0001] The invention belongs to the technical field of oil field chemistry, and in particular relates to an accelerator for oil layer protection, and also relates to a preparation method of the accelerator for oil layer protection. Background technique [0002] Reservoir damage refers to the phenomenon that the natural ability of fluid production and injection can be reduced around the well wall of the reservoir during the process of drilling, well completion, and oil well development, which eventually leads to a decrease in the permeability of the reservoir or around the well wall. In the process of oil field production, almost all operations may cause damage to oil and gas layers and reduce the production of oil and gas wells. The main influencing factors of reservoir damage are: solid phase invasion; clay hydration expansion; particle migration to form inorganic or organic precipitation; Jiamin effect or water lock; formation of emulsion to increase flow r...

AI Technical Summary

Problems solved by technology

However, domestic oilfields are currently facing the severe situation of insufficient reserve reserves, rapid production decline in old areas, and difficulty in stabilizing production; turning to the development of oil layers with poor physical properties, targeting low-porosity and low-permeability reservoirs or reservoirs with strong water-sensitive reservoirs. During operations such as well killing, well flushing, pump inspection, acidizing, fracturing, water plugging and profile control, incompatible foreign fluids entering the reservoir will cause sensitive damage to the reservoir, resulting in a decrease in production or injection rate

After these incompatible foreign fluids enter the formation, they will destroy the original equilibrium state of the reservoir, causing the clay minerals in the oil layer to expand, disperse and migrate to block the pores and throats of the formation, resulting in a decrease in permeability and affecting oil production or water injection.

Although the existing oil layer protection working fluids, such as clay anti-swelling agent, plugging release agent, and water lock release agent, also have a certain oil layer protection effect, but for low porosity and low permeability reservoirs, the oil layer protection effect is not obvious; the existing oil layer The anti-swelling rate, erosion resistance, surface tension and other indicators of the protective working fluid can no longer meet the needs of on-site construction in low-porosity and low-permeability reservoirs

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