Apparatus for heating and drying articles

Claim 2

Apparatus for heating and drying articles under vacuum by the condensation heat of the vapor of a solvent comprising: an evacuable drying chamber containing therein articles to be dried; a vacuum pump means for evacuating said drying chamber; thin film evaporator means supplying to said drying chamber a first liquid evaporated in said thin film evaporator means, the vapor of said first liquid being condensed within said drying chamber on said articles to be dried; a first condenser connected to said drying chamber for condensing a part of said solvent vapor; a second condenser connected by a throttle valve to said first condenser; a separation tank which collects condensate from said first and said second condensers; a collecting container wherein said condensed first liquid and a second liquid having a higher boiling point than said first liquid are collected, said collecting container being refilled with condensate from said separation tank; a feed pump feeding back a mixture of said first and said second liquid to said thin film evaporator wherein said first liquid is evaporated to a residual concentration in said second liquid; pressure barrier means through which said second liquid with a residual concentration of said first liquid escapes in re-evaporator means wherein the residual concentration of said first liquid is lowered by evaporating said first liquid, the vapor of which condenses in said second condenser; and oil collecting container means for collecting said second liquid.

Claim 3

Apparatus according to claim 1 wherein said thin film evaporator comprises a falling film evaporator.

Claim 4

Apparatus according to claim 1 wherein said oil collecting container means is heat insulated.

Claim 5

Apparatus according to claim 3 wherein said oil collecting container means is heated.

Claim 6

Apparatus according to claim 1 further comprising a first shut-off valve arranged between said pressure barrier means and said re-evaporator means, a connection line having a second shut-off valve arranged between the connection of said pressure barrier means and said first shut-off valve and second collecting container means for said drying chamber, with nonevaporating parts of said liquid being passed into said second collecting container means through said connection line when a high temperature exists in the drying chamber.

Claim 7

Apparatus according to claim 1 wherein said re-evaporator means consist of a part of said thin film evaporator means.

Claim 8

Apparatus for heating and drying articles comprising: an evacuable drying chamber for heating therein articles by condensation heat of the vapor of a first liquid supplied to said drying chamber; vacuum pump means for evacuating said drying chamber; vapor condenser means connected between said drying chamber and said vacuum pump means; thin film evaporator means receiving from said drying chamber condensate comprised of said first liquid and a second liquid having a higher boiling point than said first liquid obtained from articles within said drying chamber, said evaporator means effecting evaporation of said first liquid and return thereof to said drying chamber; a collecting container for receiving from said evaporator means condensate not evaporated in said evaporator means; pressure barrier means arranged between said evaporator means and said collecting container; and re-evaporator means arranged between said pressure barrier means and said collecting container, said re-evaporator means lowering the residual concentration of said first liquid and being connected to said vapor condenser means thereby to reduce the residual concentration of said first liquid to a value corresponding to the vapor pressure in said vapor condenser means; said apparatus further comprising a first shut-off valve arranged between said pressure barrier means and said re-evaporator means, a connection line having a second shut-off valve arranged between the connection of said pressure barrier means and said first shut-off valve and second collecting container means for said drying chamber, with nonevaporating parts of said liquid being passed into said second collecting container means through said connection line when a high temperature exists in the drying chamber.

Claim 9

Apparatus for heating and drying articles comprising: an evacuable drying chamber for heating therein articles by condensation heat of the vapor of a first liquid supplied to said drying chamber; vacuum pump means for evacuating said drying chamber; vapor condenser means connected between said drying chamber and said vacuum pump means; thin film evaporator means receiving from said drying chamber condensate comprised of said first liquid and a second liquid having a higher boiling point than said first liquid obtained from articles within said drying chamber, said evaporator means effecting evaporation of said first liquid and return thereof to said drying chamber; a collecting container for receiving from said evaporator means condensate not evaporated in said evaporator means; pressure barrier means arranged between said evaporator means and said collecting container; and re-evaporator means arranged between said pressure barrier means and said collecting container, said re-evaporator means lowering the residual concentration of said first liquid and being connected to said vapor condenser means thereby to reduce the residual concentration of said first liquid to a value corresponding to the vapor pressure in said vapor condenser means; said apparatus further comprising a first shut-off valve arranged between said pressure barrier means and said re-evaporator means, a connection line having a second shut-off valve arranged between the connection of said pressure barrier means and said first shut-off valve and second collecting container means for said drying chamber, with nonevaporating parts of said liquid being passed into said second collecting container means through said connection line when a high temperature exists in the drying chamber.