The black liquid soap or coarsely the manner null a which from the tall oil recovers non- saponification ones in high

摘要

PROBLEM TO BE SOLVED: To efficiently recover neutral compounds in black liquor soap and to obtain materials for producing medical supplies and nutrient preparations by dehydrating black liquor soap solution and then by distilling the dehydrated black liquor soap through a molecular distillation column or the like. ;SOLUTION: This method comprises dehydrating black liquor soap solution as a by-product or the like in a manufacturing process for Kraft pulp, feeding the dehydrated black liquor soap to a molecular distillation column or a short circuit distillation column 1, distilling the soap, collecting flows of distillate and residual solution and recovering neutral compounds (e.g. sterol esters, aliphatic alcohols or the like) in black liquor soap. The dehydration step of black liquor soap solution is preferably conducted by feeding the soap solution to a spray dryer, by bringing the sprayed solution into contact with the flow of hot gas at 150-250°C and by collecting the dehydrated soap solution flow, or by feeding the soap solution to a falling film evaporator 1 where its evaporative surface 2 is at 100-250°C and the pressure is 100-1,000 millibars and then by collecting the dehydrated soap solution flow.;COPYRIGHT: (C)2000,JPO