Verfahren zur Behandlung von Schlaemmen

Die Erfindung betrifft ein Verfahren zur Behandlung von Schlaemmen, in denen die Feststoffpartikel in einer stabilen Dispersion vorliegen, wie Laeppschlaemmen, Honschlaemmen oder dergleichen, wobei die Feststoffpartikel als feste Phase von der fluessigen Phase getrennt werden, wobei vor der Trennung dem Schlamm amphiphile Hilfsstoffe zugesetzt werden.

EP 1050512 A UPAB: 20010110 NOVELTY - Before separation of the sludge, amphiphilic agents are added. DETAILED DESCRIPTION - Preferred features: The addition converts the sludge into a state in which it settles under gravity into a compact sediment with clear supernatant liquor. Settlement under gravity continues for 1 hour, or preferably only 15 minutes. Following sedimentation, the liquid is separated by centrifugation. The sediment is then pressed to remove more liquid, which is intercepted. The solid phase is briquetted. The liquid phase is filtered, adding the solids arising, to the previously-separated solid phase. Amphiphilic agent is separated from the liquid and the solid phases by distillation and drying, respectively. It is then recycled, and/or purified by distillation. USE - A method especially suitable for fractionation of sludges, particularly inorganic sludges arising in lapping and honing operations. ADVANTAGE - Complete, immediate separation of such sludges is not possible. The new process avoids disposal and incineration, offering a method recovering both fluid and solid. Abrasives recovered include e.g. silicon carbide, boron nitride, corundum and/or diamond particles. These comparatively valuable substances can be re-used. Addition of low viscosity lipophiles is ineffective; only by use of short chain amphiphiles is the dispersion significantly de-stabilized, resulting in compact sedimentation under gravity, leaving clear, oil-containing supernatant liquid above. Conventional processes complete preparation of the separated fractions. The method is particularly suitable for sludges containing stable dispersions of oil and emulsifiers, as with lapping and honing abrasives. The viscosity is comparatively high, making conventional separations ineffective. Examples, and comparative tables of results are included in this disclosure.