Is wastewater evaporation a problem with the use of MVR and multi-effect evaporation?

Both MVR and multi-effect evaporation aim to reduce the operating costs of wastewater evaporation. The basic principle of MVR is to recompress secondary steam, increase its pressure and temperature, and reuse it to heat the heat exchanger, ultimately achieving energy savings.
    The basic principle of multi-effect evaporation is that secondary steam enters the next effect evaporator for heating, thus achieving steam reuse. However, the efficiency of multi-effect evaporation is often limited due to various factors. From the perspective of saving steam alone, MVR (Multi-Effect Vapor Reduction) definitely saves more steam than multi-effect evaporation.
    Initial cost: Compared to multi-effect evaporation, MVR requires an additional steam compressor and single-effect heat exchange area, while reducing the related equipment and condensing equipment of multi-effect evaporation. Due to the high cost of steam compressors and the increased heat exchange area, the total cost of an MVR evaporator with the same processing capacity is often three to four times that of a multi-effect evaporator.
    Operating Costs: MVRs are suitable for evaporating liquids whose boiling point increases only slightly with concentration, such as those used in the food industry (e.g., juice) and for evaporating low-concentration liquids (including salt solutions). In these cases, MVRs offer an advantage in terms of operating costs. However, if the boiling point of the wastewater increases rapidly with concentration, the increased temperature required for compression necessitates higher compressor power, significantly reducing economic efficiency.