What is Mechanical Vapor Recompression (MVR) and when is it used?

MVR compresses vapor from an evaporator to raise its saturation temperature, allowing it to be used as heating steam for the same evaporator. This dramatically reduces external steam consumption - a single MVR evaporator can achieve steam economy of 10-30 (vs. 0.9 for single-effect). Energy input shifts from steam to electricity (compressor). MVR is economically attractive when: electricity is cheap relative to steam, high steam costs justify capital investment, and the temperature lift required is modest (<15-20C). It is common in dairy, chemical, and wastewater applications.