A Study on Water Purification for Ocean Environments and Ocean Space Utilization Systems

为研究“海洋环境与海洋空间利用系统的水质净化”，本课题开展了以下几个方面的研究工作：1)人工泻湖的功能与利用概况；2)海洋空间利用的人工泻湖与浮式结构组合系统的研究；3)人工泻湖净水的基础研究本研究取得了以下成果：1)在人工泻湖(透水堤)设计中，(1)破水(2)波浪曝气；(3)水流运动催化氧化；人工泻湖有很多好处，与单一使用海洋结构用于海洋空间利用有关的大多数问题将得到解决。人工泻湖与浮式结构物相结合的海洋空间利用系统，与填海造岛相比，在造价和工期上都具有一定的优势。3)环境条件的现场测量结果表明：(1)由于设置了碎石堆防波堤，泻湖内的有效波高降至外界的10%左右，并消除了波浪的高频分量；(2)利用岸边效应模型试验结果，可以估算出泻湖内的波高。(3)悬浮体(SS)是一种有效的消波方法去除在泻湖中(4)净化效果强烈依赖于一年中的季节。4)为了定量评价人工泻湖的净水功能，利用人工泻湖生态系统建立数学模型是必要的。

In order to study on "Water Purification for Ocean Environments and Ocean Space Utilization Systems", the following research items have been done during the term of this project :1) Survey of the function and utilization of the artificial lagoon2) Study on the combined system with the artificial lagoon and floating structure for ocean space utilization3) Basic study on water purification by an artificial lagoonFrom this study the following results have been obtained :1) In the design of the artificial lagoon (permeable bank), the function of (1) breaking water (2) aeration due to waves (3) catalytic oxidation due to movement of waters, is important.2) An artificial lagoon has a lot of benefit and most of the probems relating to the single use of ocean structure for ocean space utillization will be solved. The combined system with an artificial lagoon and floating structure for ocean space utilization has an advantage in terms of the construction costs and the term of construction when it is compared with that of a reclamation island.3) The results of field measurements of the environmental conditions show that (1) significant wave height in the lagoon decreases to about 10% of that of the outside and the high-frequency components of waves are also eliminated due to the rubble-mound breakwater (2) wave height in the lagoon can be estimated by using the results of model test for bank effect (3) SS (suspended solid) is effectively removed in the lagoon (4) purification effect is strongly depend on the season of the year.4) In order to evaluate the water purification function of artificial lagoon quantitatively, the establishment of the mathematical model using ecosystem of artificial lagoon is necessary.