Thermodynamic performance evaluation of an innovative steam compressor using zeolite-water adsorption reactor

The industrial sector is a large energy consumer producing huge amounts of low enthalpy waste steam which can be compressed to increase its condensation pressure for its subsequent effective use. In this paper, adsorption technology was used to increase the waste steam enthalpy since this process requires small amounts of electrical energy. An innovative configuration of the adsorption compressors is presented involving direct contact between an adsorbent bed and the waste steam. The direct-contact design avoids the use of a heat exchanger between the steam and the zeolite adsorbent material, thus reducing the geometry complexity and the overall cost. The direct -contact technology is new and generally studied for heat pump purposes. This paper numerically investigates the physical feasibility of the process highlighting its main advantages and limitations. The results show a promising thermodynamic behaviour suggesting the possibility of using this adsorption compressor for several industrial processes involving higher than 7 bar steam pressure and pressure ratios up to 1.26. The steam consumption was lower than one order of magnitude of the usable compressed steam.