DESALT Diffusion Dialysis (DD) Equipment

• Membrane Separation: The diffusion dialyzer utilizes a semi-permeable cation or anion ion-exchange membranes. These membranes selectively allow certain ions or molecules to pass through while blocking others based on their size, charge, or chemical affinity.

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• Diffusion Process: The device operates based on the principle of diffusion, where substances move from a region of higher concentration to a region of lower concentration. In the context of acid recovery, the acid molecules (such as HCl or H₂SO₄) in the waste stream diffuse through the membrane into a separate chamber containing a less concentrated acid solution or water.

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• Dialysis System: The dialyzer is designed with two compartments separated by the membrane. The waste stream containing the acid/alkali is fed into one compartment, while a stream of deionized water or a dilute acid/alkali solution is fed into the other compartment. Due to the concentration gradient, the acid diffuses across the membrane from the waste stream to the recovery stream.

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• Continuous or Batch Operation: The diffusion dialyzer can be operated either in a continuous mode, where streams are continuously fed and collected, or in a batch mode, where a set amount of solution is processed at a time.

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• Recovery Efficiency: The efficiency of acid/alkali recovery depends on various factors, including the type of membrane used, the concentration gradient, the flow rate of the streams, and the temperature of the system. Proper control of these parameters can optimize the recovery process, leading to significant cost savings and environmental benefits. In certain scenarios the recovery efficiency reaches more than 90% of spent acid.