PROCESS FOR CAPTURING A HEAVY METAL CONTAINED IN A MOIST GAS, INTEGRATING A HEAT PUMP TO COOL THE GAS BEFORE ELIMINATING WATER

摘要

Capturing mercury or arsenic heavy metal from a moist gas containing water vapour, by:
a) cooling the moist gas by heat exchange with a heat transfer fluid produced ine) in order to obtain a gas cooled to a temperature Tf, vaporizing the heat transfer fluid;b) separating condensed water and condensates contained in the cooled gas obtained in a) obtaining a gas depleted in water and a liquid stream containing water;c) compressing vaporized heat transfer fluid obtained from a) obtaining compressed heat transfer fluid;d) heating water-depleted gas by heat exchange with compressed heat transfer fluid obtained in c) obtaining a cooled heat transfer fluid and a gas reheated to a temperature Tc;e) decompressing cooled heat transfer fluid obtained in d), recycling heat transfer fluid to a);f) contacting reheated gas obtained in d) with a capture mass for said heavy metal.

主权项

1. A process for capturing at least one heavy metal selected from mercury and arsenic, contained in a moist gas comprising water vapour, in which the following steps are carried out:
a) cooling (1000) the moist gas by heat exchange with a heat transfer fluid produced in step e) in order to obtain a gas cooled to a temperature Tf, the heat transfer fluid being vaporized during step a); b) separating (2000) at least a portion of the condensed water contained in the cooled gas obtained in step a) in a manner such as to obtain a gas which is depleted in water and a liquid stream containing water; c) compressing (4000) the vaporized heat transfer fluid obtained from step a) in a manner such as to obtain a compressed heat transfer fluid; d) heating (1002) the water-depleted gas by heat exchange with the compressed heat transfer fluid obtained in step c) in order to obtain a cooled heat transfer fluid and a gas reheated to a temperature Tc; e) decompressing (5000) the cooled heat transfer fluid obtained in step d), the decompressed heat transfer fluid being recycled to step a); f) bringing the reheated gas obtained in step d) into contact (3000) with a capture mass for said heavy metal in order to obtain a gas depleted in heavy metal.