Process for recovering organic acids from bleaching liquors

Abstract

The invention relates to a process for treating bleaching liquors from pulping processes based on organic acids. The process is characterized in that inorganic acid, such as nitric acid, phosphoric acid and/or sulphuric acid, is added into a bleaching liquor obtained from the bleaching or a stage closely associated with bleaching, whereby organic acids contained in the bleaching liquor are released into the bleaching liquor. The organic acids are then separated from the bleaching liquor and recycled to the cooking stage to be used as cooking chemicals. The nitrogen-, phosphor- and/or sulphur-containing product thereby produced, from which organic acids have been separated, is recovered to be used as a fertilizer or as raw material for a fertilizer.

Dependencies are inferred from the claim text.