Abstract: An apparatus for concentrating a dilute solution comprising a heat receiving thin plate which has a good thermal conductivity and is provided on its rear surface not facing a heat source with a liquid absorbing layer for absorbing a solution supplied thereto for concentration, and at least one condensation thin plate which has a good thermal conductivity and is provided with a liquid absorbing layer on at least one surface thereof, the heat receiving plate and the condensation plate or plates being arranged in parallel spaced relationship with each other and each of them being partly formed with at least one groove for supplying the solution to be concentrated to the liquid absorbing layers. A dilute solution supplied to and impregnated in the liquid absorbing layers through the grooves is concentrated by the heat supplied to the heat receiving plate or the latent heat of condensation released to the condensation plate.

Abstract: An apparatus for distilling water in which a heat receiving plate member and a plurality of cooling plate members have a means for holding water to be treated on each reverse side thereof and are arranged in parallel spaced relationship with each other, and the water vapor produced by heating the heat receiving surface of the heat receiving plate member is condensed on the condensing surface of the adjacent cooling plate member, while giving the latent heat of the condensation to the cooling plate member and heating a water held on its back to produce the water vapor which is condensed on the condensing surface of the next cooling plate member, such evaporation by the latent heat and condensation being conducted according the number of rooms partitioned by adjacent two cooling plate members. There are apparatuses of two types, i.e.

Abstract: A process and an apparatus for distilling water in which a heat receiving plate member and a plurality of cooling plate members have a means for holding water to be treated on each reverse side thereof and are arranged in parallel spaced relationship with each other, and the water vapor produced by heating the heat receiving surface of the heat receiving plate member is condensed on the condensing surface of the adjacent cooling plate member, while giving the latent heat of the condensation to the cooling plate member and heating a water held on its back to produce the water vapor which is condensed on the condensing surface of the next cooling plate member, such evaporation by the latent heat and condensation being conducted according the number of rooms partitioned by adjacent two cooling plate members. There are apparatuses of two types, i.e.