Application characteristics of CO2 rock blasting
CO2 gas can be converted into liquid under a certain high pressure. Liquid CO2 is compressed into a cylindrical container (fracturer) by a high-pressure pump. When a microcurrent passes through the electric ignition head, it causes the heating agent to generate high temperature, instantly gasifies the liquid CO2, and rapidly expands to generate a high-pressure shock wave, causing the energy release device to open, generating an expansion pressure of more than 300MPA, and instantly releasing high-pressure gas to cause the rock to break and loosen. Because it operates at low temperature, it does not blend with the liquid and gas in the surrounding environment, does not produce any harmful gases, does not produce arcs and electric sparks, and is not affected by high temperature, high heat, high humidity, and high cold. It has a diluting effect on gas during underground fracturing, without vibration or dust. CO2 is an inert, non-flammable and explosive gas. The fracturing process is a process of gas expansion, physical work rather than chemical reaction.
2. Characteristics of CO2 rock explosion:
(1) It has inherent safety characteristics. It is very safe in terms of storage, transportation, carrying, use, and recycling. The main machine is separated from the blasting equipment, and the time from filling to the end of blasting is short. It only takes 1-3 minutes to inject liquid CO2, and only 0.4 milliseconds from initiation to end. There are no duds during the implementation process. The safety warning distance is short and there are no safety hazards. The fracturing device is easy to recover and can be reused.
(2) It can be both directional and delayed, especially in special environments such as residential areas, tunnels, subways, underground, etc. There is no destructive vibration and shock wave during the implementation process, and there is no destructive impact on the surrounding environment.
(3) It does not destroy the texture structure in stone mining, and the yield rate and efficiency are high.
(4) No detonator or explosives are required, and the management is simple and the operation is easy to learn.
(5) Its performance is more prominent when used in mines, whether it is a high-gas mine, a rock burst mine, a mine with complex hydrogeological conditions, or a mine prone to spontaneous combustion.
(6) The material source is rich and can be obtained locally. Reduce the complicated approval and review procedures and management restrictions.
(7) According to the construction site conditions, the fracturing device pipes can be connected in series or the fracturing device model can be changed.
(8) In emergency rescue, all facilities can be shipped on any means of transportation. However, detonators, gunpowder, explosives, etc. are controlled items and do not have this advantage. A lot of rescue time can be saved.
(9) Due to the destructiveness of explosives, detonators, etc. to society and the environment, they will be more strictly controlled. Therefore, the blasting procedures will take a long time. However, the use of a fracturing device can be used for fracturing operations at any time to meet the needs of engineering construction.
