Master thesis / Masterarbeit
Production and analysis of bio-charcoal and activated-bio-char from waste materials
Summary: One of the new alternative methods for the conversion of biomass, which aim to optimize the process for coal production as the main product, is the so-called biomass steam processing (BSP), a patented process from Engler-Bunte-institute of KIT and EnBW AG. In this method, the biomass is treated in an overheated steam atmosphere at elevated temperatures at atmospheric pressure. The solid product has a significantly increased carbon content and calorific value compared to the virgin feedstock and the quality is comparable to brown coal. In order to optimize the BSP process ecologically and economically, various applications are proposed for the product coals. In addition to the energetic application (co-firing fuel in power plants) and agricultural usages (such as soil enrichment), production of activated carbon for filter applications is possible. The current research focus is on activated carbon production and related analysis.
Within the framework of this master thesis, the different waste biomasses such as compost input fractions should be carbonized via BSP in a newly designed (technical scale) rotary-drum reactor with electric heating. Results should be compared with previous tests in a screw reactor that has been used for optimizing the experimental parameters of the process. BSP products furthermore should be converted into activated carbon in the same device. Subsequently, the resulting activated carbon should be analyzed and examined for their adsorption capacity (BET surfaces). The results should be classified by comparing different bio-chars and the optimal experimental parameters (feedstock, temperature, residence time) for the production of activated carbon. To assess the quality of the activated carbons, the BET surface area and the burn off (mass loss on activation) of the activated carbon will be used as the index parameters and the optimum parameters for the best quality will be found.
During the working time, the required optimization and improvement of the rotary kiln reactor have to be taken into consideration.
1. Literature research / introduction to the topic.
2. Production and analysis of coal from different feedstocks with the new rotary kiln reactor
3. Activation and analysis of the produced activated carbons.
4. Determination of the optimal test for both processes and comparison with previous optimizations with other devices depending on the desired application.