Ocean sludge exerts a very big environmental load to local sea area. Here, attention was paid to micro-bubble technology for application to the purification of the sludge. The important point in this technique is to activate the bacteria existing in the area by micro-bubbles. We had developed a method for decomposing the sludge by using of microorganisms in an aerobic state by micro-bubble. We had very good results by the method, and also understood that hydrogen sulfide is reduced at first and then the nutrients will be reduced. Here, we have also a technique for purification by using "coagulants". Therefore, we proposed the experimental way which hydrogen sulfide is reduced at first by using "coagulants" and then the nutrients will be reduced by micro-bubble and activating microorganisms. Here, we used the detergents including enzyme as the microorganism activator. Our research object in this paper is to check the purification performance for sludge by our proposed experimental way. From the results of our experiments, we succeeded in reducing the time needed to purify the sludge, and we obtained the very good performance.
It is very important to reduce sedimentary sludge in the ocean. Plans to reduce the sludge are usually dreading or sand covering. Dredging is a simple way and aims to cut off the sludge. But after cutting off, treating the dredged sludge takes much more time and, of course, cost. Sand covering, in general, gives a big load to living organisms and the ecological system. Here, a more efficient way is needed to reduce the sludge while not imparting environmental load in the local sea area. Now, we have micro-bubble technology. So, we had developed a method for decomposing the sludge by using of microorganisms in an aerobic state by micro-bubble.