(168a) Counter-Current Multistage Solids Washing: Continuous Separation of Solid Particles from Organic Pollutants

A novel process scheme for true counter-current multistage solids washing is introduced. The pilot plant setup utilizes an apparatus previously designed at the Institute of Chemical Engineering and Environmental Technology (CEET), the Taylor Couette Disc Contactor (TCDC).[1] Due to its optimized design, this apparatus is uniquely capable of multistage washing operations in only one column, thereby enabling processes in fields where high cost effectiveness is required.

The first field where the pilot plant was applied is the continuous washing of salts recovered from crude glycerol waste. The crude glycerol itself stems from biodiesel production, where one ton of crude glycerol is produced for every ten tons of biodiesel. The crude glycerol is usually distilled to harness high purity glycerol, which leaves behind a high viscosity organic waste together with a significant amount of suspended salt particles. This high viscosity mixture was chosen as first proving candidate for the novel washing setup, with the goal of full valorization of salts, an otherwise costly discarded waste stream.[2]

[1] DOI: 10.1002/ceat.201600191

[2] DOI: 10.1016/j.cep.2023.109465