Preliminary Assessment and Experimental System for Converting VOC Fumes to Hydrogen Energy

摘要

The solvents used in painting and finishing are the primary source of volatile organic compounds (VOCs) in automotive manufacturing. Traditionally, VOCs have been incinerated in a Regenerative Thermal Oxidizer (RTO) that is heated using natural gas and emits significant amounts of CO2 and H2O to the atmosphere. The Fumes to Fuel process has been developed by Ford Motor Company to concentrate these VOCs. Optionally, hydrogen can be generated from the VOCs via steam-reforming, and purified for use in hydrogen fuel cell-powered forklifts. This process greatly reduces the amount of CO2 emitted and generates clean energy. The overall efficiency of hydrogen production can be improved by adding a pre-reforming step before the primary steam reformer. The pre-reforming is done in the concentrator where a limited amount of VOCs are converted into hydrogen and carbon oxides. This work examined potential opportunities of the Fumes to Fuel process, including application throughout all automotive assembly plants as well as other industries to produce significant amounts of hydrogen for fuel cells. This study was followed by preliminary kinetic testing to validate an experimental setup that was built to test the catalytic performance of adsorbent supported VOC reforming catalyst. Methanol steam reforming kinetic measurements were done using a bench mark Cu/ZnO/Al2O3 catalyst at temperatures of 200, 240, and 260 °C. Rate constants and the activation energy from these tests were compared with values from the literature and good agreement was demonstrated. The experimental setup will be used in future studies of potential adsorbent supported catalysts for pre-reforming of VOCs. These catalysts were prepared by impregnating adsorbent materials with noble metals and then characterized, though improvements should be made to the procedure, included testing different supports. These catalysts are to be tested in the experimental setup in the future now that the experimental setup is proven. The objective is to use these results to evaluate the possibility of carrying out some pre-reforming in the desorber/concentrator step of the Fumes to Fuel process leading to improved overall performance.