摘要 |
<p>PROBLEM TO BE SOLVED: To improve the reduction of volume by adding an alkali metallic aluminate and next, an acidic aq. solution of a polyacrylate into dredged bottom mud having equal to or above a specific water content ratio to form floc and after adding an inorganic salt if necessary, dehydrating naturally or forcibly. SOLUTION: The floc is prepared by sufficiently mixing under a low viscosity the dredged bottom mud composed of 20 g dredged bottom mud anhydride of a lake or river and 80 g water and having >=400% water content with the alkali metallic aluminate or an alkali metallic silicate and after that, adding an acidic solution of the polyacrylate. Further the inorganic salt is added if necessary and the floc is slowly stirred for a prescribed time to condense the floc, which is initially soft, to form hard and strong floc and the floc is dehydrated naturally or forcibly by using a bench press dehydrator. As a result, the dredged bottom mud is improved to be reduced in the volume while suppressing the effect on the environment to the minimum.</p> |