| 摘要 |
<p>The present invention relates to a method for the treatment of bottom ashes deriving from combustion processes, said method comprising a step of storing and aging bottom ashes and a step of grinding stored and aged bottom ashes, as well as a subsequent water washing step of said stored and aged bottom ashes. The water washing step is divided into two distinct washing stages, in every one of which water washing is combined with at least one screening step and one step of sand slime removal and hydrocyclone treatment and between which a further grinding step of the bottom ashes hold by screening in the first washing stage is carried out. The water used to wash bottom ashes is made to continuously recirculate in each washing stage after a step of clariflocculation with chemical treatment and fresh water is supplied in the second washing stage only. Thanks to these features, it is possible to reduce the content in polluting substances contained in the bottom ashes within the limits provided by the present standards concerning their reuse as inert materials, by using a much smaller amount of fresh water than that used in known treatment apparatuses for bottom ashes based on water washing. The invention also relates to an apparatus configured so as to carry out the treatment method.</p> |
