What about the energy balance? If your capture is exothermic you will warm up the cooling water and your client will not have enough cooling for their process. When you regenerate, do you need to add energy? How much CO2 is generated by the energy you need?. If you have to add heat to regenerate, how do you now cool the water back down to the temperature required by your client? Most industrial cooling systems use carbon steel pipes, shells and tubesand, although many heat exchangers will be stainless steel especially if they are plate type. Chemicals are added to prevent scale and to inhibit corrosion. You CO2 capture chemical needs to be comparable.