No its got a use. Its used to scrub the CO2 from air that is sucked into the skimmer. So if you want to raise pH in your tank, you need to lower CO2. Normal room air going into a skimmer might have a CO2 level of well over 400 ppm, in my case during the day it seemed to calculate at about 1200 ppm, pushing my pH right down to 7.9. If I had put a cannister of the soda lime you linked to in line with my skimmer, so the room air went through the soda lime before it got to the skimmer, then the CO2 in the air would be reduced to much lower levels. With a large enough scrubber (IE enough soda lime), the air would have practically zero CO2. That air, going into the skimmer, will push tank pH right up.
In my case it turned out simpler to use outside air, by running the air intake for my skimmer through a tube to the outside of the house. That pushed my pH up to about 8.4.
If you want to remove the CO2 from the calcium reactor effluent, one way to do that would be to run it into a small skimmer fed with either outside air, or air that had been scrubbed by the soda lime. That way, the high CO2 calcium reactor effluent will run into a skimmer where it is contacted with lots of air which is low in CO2, and that will pull the CO2 out of the water.
Outside air is cheaper and easier for many people (me included). If your house is not well sealed or does not have many people living in it, you might not even need the outside air. You could try just running the calcium reactor effluent into your skimmer for instance.
Remember though that if you pull too much CO2 from the calcium carbonate rich water coming out of the calcium reactor, some of the calcium carbonate might precipitate, as its the CO2 which keeps it dissolved. If you want your tank to have a higher pH, just using outside air / scrubbed air on the intake to your main skimmer, and running the calcium reactor effluent back to the DT (not the skimmer) might be best to avoid that.
