Advance CO_2 Ocean Disposal for Long-term Sequestration and Reduced Biological Impact

在各种CO_2海洋封存技术中，限制大气CO_2浓度升高的措施之一是从船舶拖曳管道释放CO_2液滴，以减少船舶运动对溶解的CO_2的稀释对生物的影响。在1500米左右释放的CO_2液滴在浮力的作用下向上上升，在500-1500米深度溶解的CO_2被认为是在20-100年内向大气排放气体。本文提出了CO_2在海洋中固存的新概念，即CO_2将在比释放点更深的深度(即1500米)溶解，从而将对生物的影响降至最低。在移动船舶的拖带管末端释放CO2液滴之前，水合物水合物是通过向CO2液滴内部注入水小液滴而形成的。由于水合物密度为1.1g/cm~3，CO_2液滴包括40vol%以上的水合物线颗粒，从释放点向下沉入深海，导致更长期的封存。此外，由于海洋平均深度为4000m，CO_2液滴的长距离溶解使稀释的CO_2溶解成为可能，大部分海洋深度的、pH曲线将大于7.0，从而将生物影响降至最低。通过实验验证了这一概念。

Among various CO_2 ocean sequestration technologies, measures to restrict the increase of atmospheric CO_2 concentration, releasing CO_2 droplets from towed pipe of ship reduces biological impact by the dilution of dissolved CO_2 due to the motion of moving ship. CO_2 droplets, released around 1500m ocean depth, rise upward due to buoyancy and dissolved CO_2 at the sea depth of 500-1500m is considered to outgas to the atmosphere in 20-100 years. Here, we present a new concept of CO_2 sequestration in the ocean that CO_2 would dissolve at the sea depth deeper than the release point (I.e., 1500m) and biological impact would be minimized. Before releasing CO_2 droplets from the tip of towed pipe of moving ship, hydrate line particles are formed by injecting water small droplets inside CO_2 droplets. Since density of hydrate is 1.1g/cm3, CO_2 droplets including hydrate line particles more than 40vol% sink downward from release point into deep ocean that result in longer term sequestration. In addition, since depth of ocean is 4000m on an average, long travel distance for CO_2 droplets dissolution enables diluted CO_2 dissolution、 pH profiles in most of the part of sea depth would be larger than 7.0, Where biological impact would be minimized. The present concept is verified by an experiment.