Examination of CO2 fixation and CO2 quantification methods on work vessels

Abstract

Towards the realization of a low carbon society, the authors have devised a system in which CO2 separated and recovered from the emissions of work vessels is fed into cement slurry in the form of dry ice and fixed in the ground by using it as a solidifier in ground improvement by deep mixing treatment methods. In this study, the feeding methods of dry ice, such as feeding amount, form and addition method, were investigated to find the method with the highest fixation amount and the least loss. The amount of CO2 fixation in the indoor and full-scale experiments was confirmed using the Gasometric Method and TC analysis, and it was confirmed that the fixation amount in the full-scale experiment was maintained at the same level as in the indoor experiment. A simple and quick method of measuring the amount of CO2 fixation is desired as part of the daily management of the CO2 fixation system devised by the authors. Therefore, a measurement method with high analysis accuracy was investigated, focusing on the Gasometric Method, in which hydrochloric acid is added to a sample and the CO2 gas generated by the chemical reaction is measured as pressure. In this study, the optimal measurement method was investigated with regard to the stirring method of the sample and hydrochloric acid and the environment during the preparation of the analysis sample. TC analysis was also carried out and the validity of the measured values was evaluated.