DE527859C - Process for drying and cooling hot adsorbents - Google Patents

Description

Method of drying and cooling hot adsorbents In the Use of adsorbents to extract valuable components from liquid or gaseous mixtures for the separation of impurities and the like one in general in such a way that the absorbed components by treatment of the Adsorbent with steam, purposely superheated steam, rinsed out are, whereupon the adsorbents are cooled and in many cases, e.g. B. at the Extraction of gasoline and the like, can also be dried. To this drying and Optional cooling precaution is generally used in the art in air.

When carrying out such processes one has to take z. B. on the oxidation of the activated carbon or the substances to be obtained, e.g. B. alcohol, tied to compliance with the upper temperature limits.

When flushing with dry, superheated water vapor at atmospheric pressure the adsorbents still take significant amounts even at temperatures above 100 ° C Amounts of condensed water. So are z. B. on a certain highly active Coal at 1200 C in the same weight as superheated water vapor at atmospheric pressure 12 to 15 per cent. of the coal weight in N water. Is now after the flushing period has ended with air, which z. B. is preheated to the same temperature of 1200 C, blown, thus, as a result of the rapid removal of the water adsorbed by the coal, a rapid and strong cooling of the adsorbent. For the purpose of extensive drying the coal must now be blown with preheated air. This drying requires a considerable amount of preheated air, especially because already for the reasons given above, the temperature of the preheated air was determined by the type of charcoal the still adsorbed constituents or both dependent limits must not exceed.

According to the present invention, for drying and partly also for cooling air or another advantageously available oxygen-containing Gas or other gaseous mixture, such as. B. a waste gas from an industrial Process used in a mixture with water vapor with the proviso that the oxygen concentration of the mixture is so low that even at high temperature disruptive processes such as z. B. unwanted oxidation can be avoided.

Working according to the invention initially has the advantage that when Steaming off the adsorbent higher temperatures can be used, which enables a faster and more thorough expulsion of the adsorbed substances. At the same time, the advantage is achieved that a substantial drying of the adsorbent is achieved. So z. B. the Moisture content of a given coal in equilibrium with superheated water vapor from atmospheric pressure at 1500 only about 3 to 4 (yo compared to about 150 / o at 1200. If a mixture of z. B. same volume parts Water vapor and air passed over the adsorbent, so occurs under cooling a further removal of the water on the coal, as a result of the Lowering of the water vapor partial pressure over the coal. SobaId the temperature has sunk sufficiently, can then be blown, dried and with air alone be cooled.

In the practice of the invention one proceeds, for. B. in such a way that one steams out with superheated steam at high temperatures. After this the adsorbed substance is expelled, air is supplied, expediently in such a way that that the steam supply is gradually reduced and the air supply accordingly Diminution is increased. As soon as the temperature rises to z. B.

1200 has sunk, cold air continues to blow and chilled.

The advantages of the new process mainly affect this from the fact that the working periods can be shortened considerably and better Drying as well as better regeneration of the adsorbents is achieved, whereby the efficiency of the operating system is increased considerably.

The process is also suitable for drying and cooling adsorbents, those at more moderate temperatures, e.g. B. those below I500 are attenuated. Here, too, there is the advantage of even drying and cooling of the whole Adsorber content represents a significant enrichment of the relevant technology.

Example An adsorber filling of activated carbon loaded with gasoline is steamed out with superheated water vapor from I (SO ° C. After the adsorbed Gasoline is driven out, with the temperature of the adsorber approximately the has reached the same temperature level of about 1600 C, is by an inevitable Lever switching the steam gradually throttled and at the same time air in the steam reduction corresponding increasing amounts are added. As soon as the temper, natural to about I200 C has fallen, the cold air alone continues to blow and cool.

Claims (2)

CLAIMS: I. Methods of drying and cooling hot carbonaceous Adsorbents, such as activated carbon in particular, with the help of oxygen-containing Gases or gas mixtures, such as in particular air, characterized in that according to completed expulsion of the adsorbed constituents the drying and cooling of the Adsorbent by passing a mixture of the gas in question or Gas mixture with such amounts of water vapor that the Siauerstofflronzentration the mixture is kept substantially below that of the atmospheric air, advantageous in such a way that following the expulsion known per se by means of Water vapor, an expediently gradually increasing amount of air is added to the vapor will. 2. The method according to claim I, characterized in that after sufficient Drop in temperature, e.g. B. to about I20 ° C, blown with air alone and is cooled.