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The adsorption is a process in sludge drying that is used to clean and stabilize all types of sludge. This result is achieved by binding impurities to solid surfaces.

 

What is adsorption?

Adsorption refers to the process in which molecules or ions from a liquid, in this case sludge water, are bound to the surface of a solid auxiliary material, the adsorbent. The adsorbent can be activated carbon, zeolites or another porous material that can effectively absorb pollutants due to its large surface area and porous structure.

In sludge drying, this process is used to eliminate harmful impurities such as heavy metals, organic compounds and other toxic substances from the sludge. The process helps to make the sludge not only drier, but also more environmentally friendly by reducing the concentration of pollutants before the sludge is further processed or disposed of.

 

Simple principle, great effect - how adsorption works

In summary, the adsorption process consists of four process steps:

  1. Selection of the adsorbent: A suitable adsorbent is selected depending on the type of contaminants to be removed.
  2. Contact phase: The sludge is brought into contact with the adsorbent, often in a reaction tank.
  3. Adsorption time: The sludge remains in contact for a specified time to allow maximum adsorption of the pollutants.
  4. Separation: After adsorption, the adsorbent is separated from the purified sludge, often by filtration or centrifugation.

After adsorption, the sludge is in a much purer form and is ready for further processing steps such as thermal drying or conversion into useful products such as fertilizers or energy sources. The reduction in toxicity and volume improves the handling, storage and ecological compatibility of the end product.