Experiment of limestone dissolution under high CO_2 concentration and high pressure

高CO_2浓度高压下石灰石溶解实验

基本信息

批准号：
17201002
负责人：
KAYANNE Hajime
金额：
$ 14.14万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2007
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17201002/
关键词：
limestone calcium carbonate dissolution experiment Co_2 seauestration saturation state dissolution race alkalinity total inoreanic carbon CO2隔離

项目摘要

The purpose of this study is to estimate limestone dissolution rate by an experiment with high CO_2 concentration seawater reacting with limestone samples under 1 to 100 atm pressure conditions. This is fundamental experiment for technology to isolate CO_2 as hydrogen carbonate ion in the ocean (see the following chemical equation) by neutralization of seawater with injected CO_2 into the coral reef basement rock.CO_2 + CaCO_3 + H_2O → Ca^<2+> + 2HCO^<3->Two experimental devices corresponding to the atmospheric pressure and high pressure conditions were newly developed for this study. The former experiment was prepared preliminary study before the high-pressure experiment, and was also efficient for analysis of an impact of ocean acidification to marine biota with carbonate shell such as foraminifera and corals. The dissolution rate of several kinds of minerals in the shallow marine area is quantified from the experiment and is confirmed to be consistent with the former studies.From th … More e result of the high-pressure experiment, injected CO_2 was confirmed to be isolated in seawater by dissolution of limestone within short time period of about several minutes. In addition, restraint of the acidification of the seawater by CO_2 dissolution and decrease of the CO_2 partial pressure were also confirmed. These results indicate that the CO_2 isolation method using limestone is an effective technique. The efficiency of the isolation by the limestone dissolution was confirmed to decrease when CO_2 partial pressure of seawater was high. We calculated that the CO_2 isolation is the most effective when CO_2 partial pressure is within the range of several to tens percent of the total pressure, and thus the quantity of isolated CO_2 under the CO_2 partial pressure conditions was within an order of 10^<-1> to 100 kg in 1m^3 seawater. In addition, dissolution rate depends on flow speed in reaction vessel, which has not been confirmed in previous studies. This result should give important knowledge for the analysis of distribution and change of CO_2 isolation and limestone dissolution during actual CO_2 injection into underground or underwater limestone strata. Less

这项研究的目的是通过一项高CO_2浓度海水与在1至100 atm压力条件下的石灰石样品反应的实验估计石灰石溶解速率。这是技术的基本实验，将CO_2分离为海洋中的碳酸氢离子（请参阅以下化学方程），通过将海水注入了co_2中的海水中和珊瑚礁基底岩石。co_2 + caco_3 + caco_3 + h_2o→ca^<2+> + 2 +> + 2hco> + 2hco> + 2hco> + 2hco^<3->开发了两个实验性的调节，并供应了较高的综合设备。在高压实验之前，先准备了前一个实验的初步研究，并且还有效地分析了海洋酸化对海洋生物群对海洋生物群的影响，例如有孔虫和珊瑚。从实验中量化了浅海洋区域中几种矿物质的溶解速率，并被证实与以前的研究一致。从高压实验的更多结果中，确认注射的CO_2可以在短时间内通过limestone溶解在海水中分离出来。此外，还确认了通过CO_2溶解和CO_2二压减少对海水酸化的约束。这些结果表明，使用石灰石的CO_2隔离方法是一种有效的技术。当海水的CO_2二压压力高时，确认通过石灰石溶解的分离效率会降低。我们计算出，当CO_2二压压在总压力的几个至几米范围内时，CO_2隔离是最有效的，因此在CO_2二压条件下，分离的CO_2的数量在1M^3海水中的10^<-1>至100 kg的阶内。此外，溶解速率取决于反应血管中的流速，这在先前的研究中尚未证实。该结果应为分析CO_2隔离和石灰石溶解的分析和变化的重要知识提供重要的知识。较少的