| 摘要 |
<p>PROBLEM TO BE SOLVED: To quickly and easily determine whether or not a coal ash is suitable for use for mortar concrete by stirring and mixing the coal ash in an alkaline aqueous solution, and measuring the concentration of ammonia. SOLUTION: As the alkaline aqueous solution, a variety of alkaline aqueous solutions, e.g. at least one kind selected from among slaked lime, quick lime, barium hydroxide, or the like, is used, the slaked lime being particularly suitable because it ensures safety. When coal ash is stirred and mixed in the aqueous solution, gaseous ammonia is produced in a very short time if ammonium sulfide is present in the coal ash. As to the amount of gaseous ammonia produced, the concentration of gaseous ammonia in a closed container can be measured easily by a gas detecting pipe, and the amount of gaseous ammonia can be measured suitably without the ammonia dissipating around. Depending on the measured amount of ammonia detected, whether or not the coal ash is suitable for use for mortar concrete is determined.</p> |
