Wherever baths and washing systems are used, process wastewater is produced that has to be treated. On the one hand, to free it from dirt, residues and harmful substances, but on the other hand, the entire production cycle can be optimized through efficient treatment of the wastewater. This is because modern, well-designed process wastewater treatment can reduce energy costs, reuse process water and avoid the discharge of residual wastewater. The most important technologies for this are the vacuum compressor and the vapor recompressor. While in the latter the wastewater is heated and the hot steam is compressed by a rotary blower, in the vacuum compressor it is a refrigerant that serves the compression. A comparison of the two technologies shows that the vapor compressor is more vulnerable and requires more maintenance due to the high temperatures involved. In a vacuum evaporator, on the other hand, the operating pressure in the vessel is only 60 millibars, which means that the operating temperature is 30 to 35 degrees Celsius. As a result, there are no expenses for insulation and cooling of the medium. In addition, a higher distillate quality can be produced with vacuum evaporators.
Details can be found in mo 11 2022 or online here!