I’m not sure which pump is suitable for vacuum concentration

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I have a brine that needs to be concentrated, and then the salt is recovered through crystallization and centrifugation. I would like to use vacuum concentration. I currently have heating steam at 120°C, and I need to choose either a pump or a Roots pump to create a vacuum, so as to ensure that the brine evaporates at a lower boiling point. I wonder if either type of pump or Roots pump can achieve this? The table below shows my data. If a Roots pump is used, the vacuum level can only reach 0.005 MP; at this level the boiling point is 117.5°C. With heating steam at only 120°C, the temperature difference is too small, so this approach clearly isn’t feasible. Is there a vacuum pump that can achieve a vacuum level of 0.078 MP, so that evaporation can take place at 85.5°C? Or a lower vacuum level will also work. Vacuum level, MP; Boiling point of the mother liquor, °C: 0, 127; -0.005, 117.5; -0.02, 114; -0.024, 111.4; -0.04, 107.4; -0.054, 101.8; -0.062, 97.8; -0.071, 89.6; -0.075, 86.6; -0.078, 85.5; -0.1, 60