To decrease the alkalinity of soil by removing alkaline components to waste water by using sulfuric acid formed when a sulfur oxidizing bacterium, sulfur source, and water are supplied in the presence of oxygen.
Crushed converter slag is put into an acrylic container 1 to form a slag layer 2, reeds 3 are planted in the surface layer, and air is supplied into the slag layer 2 by a blower 4. Blast furnace slag seepage water 5 and sludge water 6, which contain sulfur and calcium, are supplied into this slag layer 2. This sludge water 6 is water by which pH of the seepage water has been adjusted to acclimatize the sulfur oxidizing bacterium. The reeds 3 supply oxygen to soil to help the growth of soil microorganisms, water is a component of a sulfuric acid production reaction by the sulfur oxidizing bacterium, is also essential to the growth of the reeds, and flows out alkali ions formed when the generated sulfuric acid reacts with alkalis from the soil. In such a way, the alkalinity can be decreased by the low-cost and effective treatment.
FUKUNAGA KAZUHISA
MIKI OSAMU
SHINOZAKI HARUHIKO
KOBAYASHI SHIGEO
AKABOSHI TETSUYA
