Nitrogen plays a crucial role in mining exploration. Its wide application not only improves the exploration efficiency of mineral resources, but also plays an important role in environmental protection and operational safety. This article introduces you to the specific application of nitrogen in mining exploration, giving you relevant data and supporting it.
Nitrogen isolation and protection
Phenomenon description:
During mining exploration, especially during drilling operations, the use of nitrogen can effectively prevent underground fires or explosion accidents.
Cause analysis:
1. Inert environment creation: Nitrogen, as an inert gas, can replace oxygen in the air and reduce the possibility of combustion of combustible gases (such as methane). Studies have shown that adding nitrogen to air containing 5% methane can significantly reduce the explosion risk of mixed gases when the nitrogen concentration reaches more than 80%.
2. Fire and explosion-proof: Under high temperature and high pressure conditions, nitrogen can inhibit the occurrence of oxidation reactions. According to experimental data, by injecting nitrogen into the mine, the downhole temperature can be reduced by an average of about 10°C, thereby reducing the possibility of fire.
Case support:
Field tests conducted in a coal mine area showed that after using nitrogen injection technology, the amount of underground gas accumulation decreased by 60% compared with the previous one, greatly improving work safety.
Protect reservoirs from damage
In mining exploration, it is crucial to protect the original state of the reservoir. Nitrogen drilling can truly achieve "zero pollution" in the reservoir. During the exploration of deep tight sandstone gas reservoirs in the Dibei block, conventional liquid medium drilling and completion technology has seriously damaged the reservoir. After the introduction of nitrogen drilling and completion technology, such as DB104 well, the daily gas production is as high as 726,000 m³ and the daily oil production is 51.36 m³. Compared with the same block, the daily gas production has increased by more than 400 times and the daily oil production has increased by 6 times. This shows that nitrogen can prevent drilling fluid from invading the reservoir, keep the reservoir original production capacity, and lay a good foundation for subsequent mining.
Ensure safe underground operations
The underground environment is complex and there are many safety hazards. The inertia of nitrogen makes it an important factor in ensuring safety. In some mining areas where flammable and explosive gases may be present, the use of nitrogen can reduce the concentration of combustible gases in the hole and inhibit the risk of combustion and explosion. For example, in coal mine exploration with combustible gases such as gas, injecting nitrogen into the hole can effectively replace the combustible gas and reduce its concentration to a safe range.
At the same time, during equipment maintenance and maintenance, nitrogen purge reactors, separators and other containers can create an oxygen-free environment, prevent the accumulation of flammable and explosive substances, and ensure the safety of operators.
Improve resource mining rate
During the mining phase, nitrogen can also play a key role. For oil fields with high gas-oil ratio reservoirs or need to maintain formation pressure, injection of nitrogen can supplement formation energy. Nitrogen oil flooding is a cost-effective gas flooding method, especially suitable for low permeability and high water content reservoirs. By injecting high-pressure nitrogen into the oil layer, the formation pressure is increased and the remaining crude oil flows to the production wells will be driven, thereby improving the crude oil recovery rate.
In addition, the nitrogen foam oil displacement technology mixes nitrogen with surfactant to form a stable foam injection into the oil reservoir, which can improve the viscosity of the injected gas, improve its fluidity in the oil layer, expand the wave and volume, and further improve the oil displacement efficiency, which has a significant effect in heterogeneous reservoirs and crack reservoirs.
Nitrogen plays an irreplaceable role in all aspects of mining exploration, reservoir protection, security guarantee and resource mining. With the continuous development of technology, the role of nitrogen in mining exploration will be more extensive and in-depth, providing strong support for the efficient, safe and sustainable development of the mining industry.
