Now the world is really on the verge of danger. When it comes to a nuclear war, no one wants it to happen. But if carbon dioxide emissions are not controlled, the global ecological situation in 80 years should be much worse than a nuclear war. Don't think 80 years is too long, it has nothing to do with me. That's what the grandchildren need to prepare.
In fact, global warming is a looming and hugely impactful threat like the "gray rhinoceros", and once it is close, there is no way to reverse it. Even if human activities no longer release a single tonne of carbon dioxide into the atmosphere from now on, global temperatures will still rise according to current inertia.
This huge inertia will last for about 150-200 years. Then, nature will fix the carbon dioxide released since the industrial revolution back into the earth's crust, animals and plants through the carbon cycle. So, in the absence of new technology, don't look at the 80 years away, but in fact, we will never be able to do it.
Fortunately, since 2010, some carbon capture and collection technologies have begun to appear, and we can take the initiative to take carbon dioxide from the air back to the ground, which has made all mankind have a little bit of a turnaround. Carbon capture technology, often referred to as "CCSU", stands for the capture, sequestration and reuse of carbon dioxide. This also happens to be the order of maturity, and the capture is the closest to maturity.
In fact, carbon capture is not a matter of taking it for granted that the air is filtered and the carbon dioxide inside is removed. That is the least mature of all the methods and the least likely to be implemented on a large scale. Because the amount of carbon dioxide in the air is so low, less than 4 parts per 10,000, it is not cost-effective to pick something out of the air with such a low content. It's a bit like you go to the desert to dig a pit to find water, I guess you dig several pits before a few drops come out, but you sweat a lot more than those few drops of water.
Therefore, the most widespread carbon capture in the future will be to capture carbon dioxide at the source of carbon dioxide emissions, that is, directly at the exhaust pipe. The concentration of carbon dioxide here is at least 10% or more, which is much higher than a few parts per 10,000. The capture method is mainly in three general directions - post-combustion capture, pre-combustion capture and oxy-fuel combustion capture.
Post-combustion capture, as the name suggests, is to connect a section of absorption and separation device after the combustion chamber of fossil energy, and use some chemical methods to adsorb carbon dioxide like a vacuum cleaner. The device captures at least 90% of the CO2 emitted and does not require major surgery on the existing plant, as long as the corresponding decarbonization equipment is added to the back end of the emissions. However, the disadvantage is that the energy consumption of capture is not low, and 1/3 of the original output power of the power plant is used to capture carbon, and it also occupies a special area.
Another way to capture carbon is to capture it before combustion, which is similar to the method of producing coal gas, in which fossil fuels are gasified under the action of high-temperature water vapor to produce carbon dioxide, carbon monoxide, methane, hydrogen, nitrogen, and everything that can be burned as fuel. The carbon dioxide that is separated first can be captured by a liquid solution. Unfortunately, this technology is not suitable for traditional coal power plants. It can only be used in new power plants and chemical plants, especially those that produce hydrogen.
Finally, oxygen-rich combustion, to what extent is this oxygen-rich rich? The oxygen content is about 95%. The benefits are high combustion efficiency, high concentration of carbon dioxide produced, and less pollution from nitrogen oxides. But the disadvantage is also very obvious, oxygen is burned at this concentration, which is too demanding for the furnace, because the temperature rises a lot at once. Still have to build a factory from scratch.
Even if CO2 is caught, this is only the first step in a long journey, because you still have to find a reliable way to store it, not in a jar, and that's another technology that needs to be solved.