A device and method for saturating tight rock

Abstract

The invention discloses a dense rock saturation apparatus and method. The apparatus mainly consists of four portions, i.e., a negative pressure extraction system, a hydraulic system, a temperature adjusting system and a control system. For the scientific difficulties of the dense rock such as domination of nano and micro holes and difficulty in saturation of liquid and particularly for the nano hole portion, under the negative pressure condition, the saturated liquid is transported to a nano capillary pipe in a dense rock core by virtue of an artificial rock core capillary pipe, the dense rockcore slowly absorbs the liquid to be saturated under the double gravity effect of the capillary pipe force and the negative pressure, and a high-fluid-saturation-degree saturated rock core can be achieved. The dense rock saturation apparatus and method are simple in structure and convenient in operation, have the characteristics of high automation and operation safety, and provide a matching apparatus and method for researching the basic sciences of the dense rock core.

Description

technical field [0001] The invention relates to the field of petroleum geological experiments, in particular to a dense rock saturation device and method. Background technique [0002] As the exploitation of oil and natural gas in conventional sandstone, carbonate rock and other reservoirs is gradually reduced, unconventional oil and natural gas has become a new trend in the development of the modern petroleum industry. As an important unconventional oil and gas, tight sandstone oil and gas and shale oil and gas Energy makes the exploration and development of unconventional oil and gas. Some previous methods and industry standards are no longer applicable to the evaluation of unconventional oil and gas reservoirs. Therefore, it is of great significance to establish targeted evaluation methods suitable for unconventional oil and gas reservoirs. [0003] Tight sandstone oil and gas reservoirs, shale oil and gas, etc. have small pore throats and are rich in clay minerals. Befor...

AI Technical Summary

Problems solved by technology

The solubility of water at normal temperature is relatively low, so it is difficult to prepare formation water with high salinity at normal temperature. If formation water with formation condition salinity is not used for saturation, the subsequent experimental results will naturally lose accuracy

[0005] Chinese invention patent CN 201210207429.9 discloses a rock liquid saturation device, Chinese invention patent CN 102841046B discloses a method and a measuring device for measuring rock porosity, and Chinese invention patent CN 202793988U discloses an evacuation and pressurization saturation device. From the point of view, it is basically only suitable for conventional cores with good porosity and permeability, and is not completely suitable for saturated liquids of tight sandstones.

Because the pore throats of tight sandstone are small, the capillary force is strong, and it is difficult to evacuate the intermediate container into a low-pressure vacuum during the vacuuming process, some gas will remain in the nano-scale pore throats, and the saturated liquid is directly put into the sample cup after evacuation. The rapid and complete submersion of the rock sample will cause the liquid to quickly enter the rock sample, and the gas in the nano-scale or poorly connected pore throat will be blocked in the core, forming the Jamin effect, causing saturation failure, and bringing errors or even errors to the subsequent evaluation. in conclusion

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