Process for drying hygroscopic materials

Claim 2

A process for drying hygroscopic materials at a predetermined humidity value which remains substantially constant throughout the process utilizing an automatic control associated with at least one timing means and humidity reduction means comprising the steps of: activating humidity reduction means to lower the humidity of the drying means, interrupting humidity reduction means when the humidity of the drying means reaches or drops below a predetermined humidity value, and allowing a predetermined time interval for the humidity of the drying means to return to the predetermined humidity value in response to the release of moisture from drying material.

Claim 3

The process of claim 1 further comprising the steps of: activating humidifying means to initiate humidity addition to the drying means if it has not attained said predetermined humidity value by the end of said predetermined time interval, and interrupting the humidity addition when the humidity of the drying means reaches or exceeds the predetermined humidity value.

Claim 4

The process of claim 2 further comprising the step of allowing the humidity of the drying means to return to the predetermined value in response to the normal absorption of moisture by the drying material during a second predetermined time interval.

Claim 5

The process of claim 3 wherein said predetermined time interval and said second predetermined time interval are at least approximately equal.

Claim 6

The process of claim 3 wherein reactivation of said humidifying means occurs before the termination of said second predetermined time interval.

Claim 7

The process of claim 1 wherein reactivation of said humidity reduction means occurs before the termination of said predetermined time interval.

Claim 8

The process of claim 1 wherein said humidity reduction means comprises incoming and outgoing air exchange means.

Claim 9

The process of claim 1 wherein humidity reduction is effected by condensation.

Claim 10

The process of claim 1 wherein the humidity of the drying means is sensed and controlled by the wet bulb and dry bulb temperatures thereof.

Claim 11

A process for drying hygroscopic materials at a predetermined humidity value utilizing an automatic control associated with at least one timing means, humidity reduction means and humidifying means comprising the steps of: activating humidity reduction means to initiate humidity removal from drying means, interrupting the humidity removal when the humidity of the drying means reaches or drops below a predetermined humidity value, allowing the humidity of the drying means to return to the predetermined humidity value in response to the normal release of moisture from drying material during a predetermined time interval during which, if the humidity of the drying means reaches or exceeds said predetermined humidity value, reactivating said humidity reduction means, and if said predetermined humidity value is not reached or exceeded by the end of said predetermined time interval, activating humidifying means to initiate humidity addition to the drying means, interrupting the humidity addition when the humidity of the drying means reaches or exceeds the predetermined humidity value, allowing the humidity of the drying means to return to the predetermined humidity value in response to the absorption of moisture by the drying material during a predetermined time interval during which, if the humidity of the drying means reaches or drops below said predetermined humidity value, reactivating said humidifying means, and if the humidity of the drying means does not reach or drop below said predetermined humidity value by the end of said predetermined time interval, reactivating said humidity reduction means.

Claim 12

A process for drying hygroscopic materials at a predetermined humidity value utilizing an automatic control associated with at least one timing means, humidity reduction means and humidifying means comprising the steps of: activating humidity reduction means to initiate humidity removal from drying means, interrupting the humidity removal when the humidity of the drying means reaches or drops below a predetermined humidity value, allowing the humidity of the drying means to return to the predetermined humidity value in response to the normal release of moisture from drying material during a predetermined time interval during which, if the humidity of the drying means reaches or exceeds said predetermined humidity value, reactivating said humidity reduction means, and if said predetermined humidity value is not reached or exceeded by the end of said predetermined time interval, activating humidifying means to initiate humidity addition to the drying means, interrupting the humidity addition when the humidity of the drying means reaches or exceeds the predetermined humidity value, allowing the humidity of the drying means to return to the predetermined humidity value in response to the absorption of moisture by the drying material during a predetermined time interval during which, if the humidity of the drying means reaches or drops below said predetermined humidity value, reactivating said humidifying means, and if the humidity of the drying means does not reach or drop below said predetermined humidity value by the end of said predetermined time interval, reactivating said humidity reduction means.

Claim 13

A process for drying hygroscopic materials which comprise contacting a hygroscopic material with a drying means, activating humidity reduction means to remove humidity from said drying means, interrupting the humidity removal when the humidity of said drying means reaches or drops below a predetermined humidity value, allowing the humidity of the drying means to increase in response to the normal release of moisture from said hygroscopic material during a first predetermined time interval, determining the humidity of the drying means at the end of said time interval whereupon the humidity of the drying means is increased when the humidity value is below said predetermined value, waiting a second predetermined period of time, reactivating said humidity reduction means, and repeating said procedure until the hygroscopic material is dried.

Claim 14

A process for drying hygroscopic materials which comprise contacting a hygroscopic material with a drying means, activating humidity reduction means to remove humidity from said drying means, interrupting the humidity removal when the humidity of said drying means reaches or drops below a predetermined humidity value, allowing the humidity of the drying means to increase in response to the normal release of moisture from said hygroscopic material during a first predetermined time interval, determining the humidity of the drying means at the end of said time interval whereupon the humidity of the drying means is increased when the humidity value is below said predetermined value, waiting a second predetermined period of time, reactivating said humidity reduction means, and repeating said procedure until the hygroscopic material is dried.

Claim 15

A process for drying hygroscopic materials at a predetermined humidity value which remains substantially constant throughout the process utilizing an automatic control associated with at least one timing means, humidity reduction means to lower the humidity of drying means, and means to determine the humidity of the drying means, where the humidity reduction means is activated when the humidity of the drying means rises above the predetermined humidity value and interrupted when the humidity of the drying means drops below the predetermined humidity value, wherein the improvement comprises: allowing a predetermined time interval for the humidity of the drying means to return to the predetermined humidity value in response to the release of moisture from the drying material due to the redistribution of moisture within the drying material.

Claim 16

A process for drying hygroscopic materials at a predetermined humidity value which remains substantially constant throughout the process utilizing an automatic control associated with at least one timing means, humidity reduction means to lower the humidity of drying means, and means to determine the humidity of the drying means, where the humidity reduction means is activated when the humidity of the drying means rises above the predetermined humidity value and interrupted when the humidity of the drying means drops below the predetermined humidity value, wherein the improvement comprises: allowing a predetermined time interval for the humidity of the drying means to return to the predetermined humidity value in response to the release of moisture from the drying material due to the redistribution of moisture within the drying material.