Definition
CO2 rock blasting, also known as carbon dioxide rock breaking or gas expansion cracking, is a technique used for rock excavation and breaking in various applications, including mining, quarrying, and construction projects. It is an alternative to traditional methods such as explosives or mechanical methods like drilling and hammering. The following describes how to use the CO2 rock blasting system.
This technology utilizes the physical principle of liquid carbon dioxide absorbing heat, gasifying and expanding in volume. After chemical heating, liquid carbon dioxide instantly turns into gas, expands in volume more than 600 times, and is released instantly, thereby breaking the rock.
The steps of rock blasting using CO2 system
- Drill holes: first, holes are drilled into the rock formation in a predetermined pattern and spacing. The drilling diameter is 130-140mm; the drilling depth is 6-8m; it depends on the specific construction requirements.
- Fill with carbon dioxide: use the carbon dioxide filling system to inject high-pressure liquid carbon dioxide into the rock-breaking steel pipe. The carbon dioxide used is usually in a supercritical state, ie above its critical temperature and pressure.
- Put the pipes into the holes: use an excavator to hoist the rock-breaking steel pipe into the hole and place it at the bottom of the hole.
- Plug the holes: plug the hole with soil or gravel. The tighter the blockage, the better the blasting effect.
- Connect wire: connect wires in parallel or in series.
- Detonate: connect the main line to the detonator and detonate.
The advantages of CO2 rock blasting system
CO2 rock breaking technology does not belong to explosives and does not require strict supervision by relevant departments and cumbersome approval procedures for explosives. Carbon dioxide is an inert gas, which is very safe in storage, transportation, use, and recycling.
The use cost is low, and the carbon dioxide rock breaking equipment can be used repeatedly, and only need to fill carbon dioxide and replace the heating tube for each use.
There is no destructive vibration and shock wave during the working process, the proportion of dust is reduced, and it will not affect the surrounding environment. The impact force is lower than the traditional explosive blasting, the impact force is generally 400Mpa, far lower than the 1000-5000Mpa of explosive blasting. The detonation velocity is about 3m/s, generally after 2-3 meters away from the blasting point, there is basically no destructive effect.
The blasting force is controllable, and different energy levels can be set according to the use environment and rock structure.
CO2 Rock Blasting VS Dynamite Blasting
Mine blasting technology has developed rapidly along with the construction of mine engineering. Different blasting methods have a great impact on mining costs. In the whole process of mining, the cost of drilling and blasting accounts for about 20% of the total cost. Selecting a specific blasting method according to the rock structure of the mine can not only improve the blasting effect but also save mining costs.
Because mine blasting is somewhat dangerous, it can only be done after undergoing stringent approval processes. Buildings are comparatively close to some mining zones. Therefore, during blasting, it is important to avoid vibration, the impact of flying rocks, and dust phenomena on nearby buildings and people in addition to taking large pieces and root phenomena into account.
Explosive blasting is the most often utilised technique in the conventional mine blasting procedure. Although it can successfully fulfil the blasting requirements, explosive blasting poses significant safety risks due to its strength and ability to destroy rocks. As a result, the explosives certification process is somewhat intricate. Carbon dioxide blasting is a relatively recent type of blasting that has arisen to address this issue. What distinguishes conventional dynamite blasting from the new carbon dioxide rock blasting, then?
Dynamite blasting
Advantages: 1. Large destructive power and remarkable crushing effect; 2. Relatively low blasting cost; 3. Simple blasting process and high blasting efficiency.
Disadvantages: 1. High-risk factor, difficult to approve; 2. Highly destructive, easy to affect surrounding buildings and residents; 3. Strong crushing, resulting in reduced utilization of stone materials; 4. Serious noise and dust pollution.
CO2 rock blasting
Advantages: 1. No need for strict approval and easy to use; 2. No vibration and low noise, reducing the impact on surrounding residents; 3. Environmental protection, reducing environmental pollution; 4. Reduce risk factors and high safety; 5. Can be repeated without interruption use.
Disadvantages: 1. The steps are too cumbersome, and the efficiency is low; 2. The effect of foundation pit excavation or bad working surface is not good; 3. Multi-row blasting cannot be realized, and the output is low; 4. The rock-breaking steel pipe-filling process and on-site construction are relatively It is complex and requires high drilling quality.
Conclusion
The CO2 rock blasting system is a safer, more environmentally friendly alternative to traditional explosive blasting. It uses the rapid expansion of liquid carbon dioxide into gas to generate controlled force, breaking rocks with minimal vibration, noise, or environmental impact. Unlike dynamite, it doesn’t require strict regulatory approvals and carries lower storage and usage risks. However, CO2 blasting is less effective for large-scale or complex projects due to its labor-intensive process and limited capacity. While it stands out for safety and environmental benefits, traditional dynamite blasting remains more efficient for large-scale operations.
Reference
https://rilonmachinery.com/co2-rock-breaking-technology-alternative-explosive-blasting/
https://rilonmachinery.com/advantages-of-co2-rock-breaking-technology/
