Calcium looping example, adding Ca-looping to all coal-fired plants in the UK would generate enough waste for 33 Mtonnes/yr of cement production, whereas current cement production in the UK is only 12.5 Mtonnes/yr. Hence, if the technology is applied on a large scale, the purge rate of CaO should be optimized to minimize waste. To fully gauge the viability of calcium looping as a capture process, it is necessary to consider the political, environmental, and health effects of the process as well. Though many recent scientific reports (e.g.: the seven-wedge stabilization plan by Pacala and Socolow) convey an urgent need to deploy
Calcium citrate sulfuric acid. In many individuals, bioavailability of calcium citrate is found to be equal to that of the cheaper calcium carbonate. However, alterations to the digestive tract may change how calcium is digested and absorbed. Unlike calcium carbonate, which is basic and neutralizes stomach acid, calcium citrate has no effect on stomach acid. Calcium carbonate is harder to digest than calcium citrate, and calcium carbonate carries a risk of "acid rebound" (the stomach overcompensates by producing more acid), so individuals who are sensitive to antacids or who have difficulty producing adequate stomach acid may choose calcium citrate over calcium carbonate