| 摘要 |
<p>A process and apparatus for treating an aqueous nitrogeneous liquor by performing ammonia oxidation and denitrification using a biosludge comprising anammox bacteria and ammonia-oxidizing bacteria, which process and apparatus can serve to obtain treated liquor of high water quality at a high treating efficiency and a high yield of ammonium nitrogen removal with easy control of supply rate of oxygen-containing gas. The technique comprises the steps of charging a reaction vessel having stored therein a biosludge comprising anammox bacteria and ammonia-oxidizing bacteria present as a suspension with a definite amount of the liquor to be treated, supplying thereto an oxygen-containing gas at a rate not obstructing growth of the anammox bacteria to thereby cause ammonia oxidation of ammonium nitrogen into nitrite nitrogen by the ammonia-oxidizing bacteria and denitrification by the anammox bacteria simultaneously, or performing the denitrification in steps by charging the reaction vessel with a part amount of one treating batch of the liquor to be treated, whereupon supply of the oxygen-containing gas is stopped and the reaction liquor is replenished with the rest amount of the liquor to be treated. The supply of the oxygen-containing gas is stopped at a point of time at which the observed value of dissolved oxygen concentration or of ORP of the reaction liquor in the reaction vessel changes abruptly.</p> |
