| 摘要 |
<p>The invention relates to a process for purifying electrical filter ash from chlorides, in particular, by means of leaching and subsequently separating off crystallized substance, which crystallized substance is returned to the process for forming black liquor. A good separation of solid phase in the form of crystalline Na2S04 is obtained by means of a repeated gentle agitation of slurried electrical filter ash in a leaching tank with a total dwell time of between 1 and 5 hours, directly followed by centrifugation of the leached electrical filter ash. The solid phase is supplied to the black liquor prior to final evaporation and/or recovery in the recovery boiler. More than 70 % of the chloride content in the electrical filter ash and 70 % of the potassium content are efficiently leached out, and an improved utilization of process chemicals is obtained.</p> |
