US 4,312,641 A · Heat-reactivatable adsorbent gas fractionator and process

Abstract

A process and appartus are provided for removing a first gas from a mixture thereof with a second gas. The gas mixture is passed through a sorbent bed having a preferential affinity for the first gas and comprising a microwave absorbent capable of absorbing microwave energy and the first gas is sorbed on the sorbent so as to produce a gaseous effluent which has a concentration of first gas therein below a predetermined maximum. Then the first gas sorbed on the sorbent bed is removed therefrom by application of microwave energy, at a temperature at which the microwve absorbent absorbs such energy and activates the first gas sufficiently to desorb the first gas, while passing a purge flow of gas in contact with the bed to flush out desorbed first gas from the bed. The bed is allowed to cool to a relatively efficient temperature for adsorption. The gas mixture is then again passed in contact with the bed. If two beds are used, one bed can be desorbed while the other is on-stream, thereby maintaining a substantially continuous flow of effluent gas. The apparatus of the invention provides a sorbent bed assembly having a microwave energy generator positioned to direct such energy into a sorbent bed comprising a microwave absorbent capable of absorbing microwave energy for desorption of first gas from the sorbent bed.

Claims33

Dependent claims

In the process for removing a first gas from a mixture thereof with a second gas by flow of the gas mixture continuously through a sorbent bed having a preferential affinity for the first gas which includes the steps of passing the gas mixture in contact with and from one end to another end of a first bed of the sorbent;

sorbing first gas thereon and, as the sorption of the first gas continues, forming a concentration gradient of first gas in the first bed progressively decreasing from one end to the other end of the bed ranging from a substantial proportion of the first sorbent capacity therefor at one end to less than 20% of its capacity therefor at the other end, so as to produce a gaseous effluent which has a concentration of the first gas therein below a predetermined maximum;
removing first gas sorbed on the second sorbent bed by passing a purge flow of effluent gas in contact with the sorbent bed, discontinuing the purge flow, and then resuming passing the gas mixture in contact with the sorbent bed, the improvement which consists essentially in utilizing a sorbent transparent to microwave energy having a frequency within the range of about 0.03 to about 3000 giga Hertz, and combining with the sorbent a microwave absorbent capable of absorbing microwave energy within said range in an amount sufficient to activate and desorb sorbed first gas on the sorbent, and then desorbing first gas by applying during the purge flow microwave energy having a frequency within the range of about 0.03 to about 3000 giga Hertz at a temperature at which the sorbent is transparent to microwave energy, the microwave energy being preferentially adsorbed by the microwave absorbent and then activating first gas sorbed on the sorbent and thereby desorbing first gas, and halting application of the microwave energy when desorption of first gas is substantially complete, and before water of hydration of the sorbent is removed.

Dependencies are inferred from the claim text.

Heat-reactivatable adsorbent gas fractionator and process

Life of this patent

Heat-reactivatable adsorbent gas fractionator and process

Life of this patent

Abstract

Claims33