Abstract
In order to utilize the products made of converter steel-making slag in marine area, knowing the leaching behavior of alkali substances and the pH rising of seawater is necessary. Most of the reported experiments for this purpose have been performed in closed system using such as a cylindrical container, but pH change under water flow in opened system is important. In this study, the experiments using large scale flume (L=6.5 m, W=0.5 m, H=1.2 m) with artificial seawater flow were performed. Five kinds of samples, 1) three kinds of steel-making slag of which particle size is 0 - 30 mm, 15 - 30 mm, 30 - 85 mm respectively, 2) artificial stone, which is solidified steel-making slag with hydration reaction, and 3) reformed soil, which is dredged soil mixed with converter steel-making slag, were used. pH values of the seawater sampled from 40 parts of the flume simultaneously were determined, and pH distribution maps were drawn with time. pH rising of the seawater for steel-making slag were 0.16 - 0.35, and slag with different particle diameter showed different behavior. On the other hand, pH rising of the seawater for artificial stone and reformed soil were within 0.04.
