Apparatus for drying materials

Claim 2

Apparatus for drying materials comprising: a sealable container for the material to be dried; means for reducing the pressure in said container by exhausting air therefrom; a closed pipe system including a heat pump having a compressor for pumping a refrigerant through said system, a condenser for the refrigerant arranged as a heating element in said container and connected with said system, and an evaporator arranged in the container as a cooler for moisture boiled off from the material being dried; and a gas permeable wall defining first and second spaces in the container, the material to be dried being located in one of said spaces in the container and said evaporator being disposed in the other of said spaces.

Claim 3

Apparatus as claimed in claim 1 in which said condenser for the refrIgerant is surrounded by said evaporator.

Claim 4

Apparatus as claimed in claim 1 in which said condenser for the refrigerant comprises two ascending pipes and a number of loops connected therewith at different levels, each loop having one end connected with one of said ascending pipes the other end being connected with the other ascending pipe.

Claim 5

Apparatus as claimed in claim 3 in which two further ascending pipes are provided together with loops connected therewith, the loops connected with one pair of ascending pipes alternating with loops connected with the other pair of ascending pipes.

Claim 6

Apparatus as claimed in claim 3 in which one of the two ascending pipes is connected with an inlet for refrigerant the other one being connected with a recipient for condensed refrigerant, the recipient being arranged below said loops.

Claim 7

Apparatus as claimed in claim 4 in which one pipe of each pair of ascending pipes is connected with an inlet for refrigerant, and the other pipe of each pair being connected with a recipient for condensed refrigerant, the recipient being arranged below said loops.

Claim 8

Apparatus as claimed in claim 1 in which the gas permeable wall is arranged as a casing surrounding said condenser for the refrigerant.

Claim 9

Apparatus as claimed in claim 7 in which said gas permeable wall comprises a perforated metal sheet wall, the perforations of which are covered by filter cloth.

Claim 10

Apparatus as claimed in claim 7 in which said container is substantially spherical and is arranged to be separated in a horizontal plane above the horizontal diametrical plane, and in which said casing has a smaller outer dimension than the opening provided by separating said container in said horizontal plane.

Claim 11

Apparatus as claimed in claim 9 in which said casing has a cylindrical part, and a frustro-conical part connected to an inlet for said material to be dried.

Claim 12

Apparatus as claimed in claim 1 in which there is provided between said compressor and said condenser for the refrigerant a heat exchanger arranged outside the container.

Claim 13

Apparatus as claimed in claim 11 in which there are provided means for supplying only part of the refrigerant flow to the heat exchanger.

Claim 14

Apparatus as claimed in claim 1 in which in connection with the evaporator forming a cooler for the removed moisture, there is provided a collecting vessel for the condensate formed, and in which said vessel is connected to a drain pipe with a pump therein for removing said condensate from the container.

Claim 15

Apparatus for drying materials comprising: a sealable container for the material to be dried; means for reducing the pressure in said container by exhausting air therefrom; a closed pipe system including a heat pump having a compressor for pumping a refrigerant through the system, a condenser for the refrigerant arranged as a heating element in the container and connected with the system, and a heat exchanger cooled by the evaporation of the refrigerant arranged in the container as a cooler for condensing moisture boiled off from the material being dried; and a gas permeable wall defining first and second spaces in the container, the material to be dried being located is one of said spaces in the container and the heat exchanger being disposed in the other of said spaces.

Claim 16

Apparatus for drying materials comprising: a sealable container for the material to be dried; means for reducing the pressure in said container by exhausting air therefrom; a closed pipe system including a heat pump having a compressor for pumping a refrigerant through the system, a condenser for the refrigerant arranged as a heating element in the container and connected with the system, and a heat exchanger cooled by the evaporation of the refrigerant arranged in the container as a cooler for condensing moisture boiled off from the material being dried; and a gas permeable wall defining first and second spaces in the container, the material to be dried being located is one of said spaces in the container and the heat exchanger being disposed in the other of said spaces.