TY - GEN A1 - Franken, Tim A1 - Matrisciano, Andrea A1 - Sari, Rafael A1 - Robles, Alvaro Fogue A1 - Monsalve-Serrano, Javier A1 - Pintor, Dario Lopez A1 - Pasternak, Michal A1 - Garcia, Antonio A1 - Mauß, Fabian T1 - Modeling of Reactivity Controlled Compression Ignition Combustion Using a Stochastic Reactor Model Coupled with Detailed Chemistry T2 - SAE technical papers : 15th International Conference on Engines & Vehicles N2 - Advanced combustion concepts such as reactivity controlled compression ignition (RCCI) have been proven to be capable of fundamentally improve the conventional Diesel combustion by mitigating or avoiding the soot-NOx trade-off, while delivering comparable or better thermal efficiency. To further facilitate the development of the RCCI technology, a robust and possibly computationally efficient simulation framework is needed. While many successful studies have been published using 3D-CFD coupled with detailed combustion chemistry solvers, the maturity level of the 0D/1D based software solution offerings is relatively limited. The close interaction between physical and chemical processes challenges the development of predictive numerical tools, particularly when spatial information is not available. The present work discusses a novel stochastic reactor model (SRM) based modeling framework capable of predicting the combustion process and the emission formation in a heavy-duty engine running under RCCI combustion mode. The combination of physical turbulence models, detailed emission formation sub-models and stateof-the-art chemical kinetic mechanisms enables the model to be computationally inexpensive compared to the 3D-CFD approaches. A chemical kinetic mechanism composed of 248 species and 1428 reactions was used to describe the oxidation of gasoline and diesel using a primary reference fuel (PRF)mixture and n-heptane, respectively. The model is compared to operating conditions from a single-cylinder research engine featuring different loads, speeds, EGR and gasoline fuel fractions. The model was found to be capable of reproducing the combustion phasing as well as the emission trends measured on the test bench, at some extent. The proposed modeling approach represents a promising basis towards establishing a comprehensive modeling framework capable of simulating transient operation as well as fuel property sweeps with acceptable accuracy. KW - Stochastic Reactor Models KW - RCCI KW - Chemical Kinetics KW - Low Temperature Combustion Y1 - 2021 UR - https://www.sae.org/publications/technical-papers/content/2021-24-0014/ U6 - https://doi.org/10.4271/2021-24-0014 SN - 0148-7191 SN - 2688-3627 ER - TY - GEN A1 - Markowski, Jens A1 - Lohse, Anja A1 - Garcia, Javier T1 - Planning and realization of a plant for the recovery of gold from thin coatings by hydro-biotechnological methods T2 - GOLD 2022 Conference, Québec City Convention Centre, July 17-20, 2022 N2 - Production waste from the manufacture of printed circuit boards often has gold-containing contact strips and dots whose gold content is very low. Recycling of these gold coatings by means of conventional melting processes is technically hardly possible, since the carrier materials often contain mechanical reinforcements and flame retardants in addition to thermosetting plastics. Furthermore, there would be significant gold losses in the smelting process. Together with two industrial partners, at BTU in the last years a technology was developed, which can be used to decoat gold-bearing waste from PCB-production and contact stripes using biotechnological methods. As a result, a complete and separate recovery of the gold tinsel and the carrier material copper with high purity is possible. The bioleaching process is realized with iron and sulfur oxidizing bacteria, especially Leptospirilum ferrooxidans and Acidithiobacillus ferrooxidans. The first pilot plant with a planned throughput of nearly 2000 kg per year is currently in realization. The biotechnological apparatus consists of a closed leaching reactor (with a capacity of approx. 300 liters of fluid) as the core element and the peripheral equipment (fermenter, cementation reactor, filter systems etc.). Compared to processes using inorganic acids, shorter leaching times can be achieved, partial regeneration and multiple use of the bioleaching solution is possible. After optimizing the conditions, a process time of only 60 hours per leaching-charge is possible. Over a period of 2-3 days, the microorganisms dissolve the copper layers present as gold carriers on the polymer. The dissolved gold flakes are filtered off and the leaching liquid containing copper is fed to the next process stage. There, during approx. 3-4 days, the dissolved copper is recovered by feeding metallic iron (with a sacrificial anode). The microorganisms present in the solution accelerate this process. All process steps take place at moderate temperatures (< 40°C) and in a slightly acidic environment. The separated gold tinsel as main product with a content of over 900 mg/g Au is a suitable input for the precious metal smelter. The copper precipitates in metallic form and can be recovered in high purity (>90%) as a by-product. Due to the biological leaching and the resulting concentration of the gold components, only < 1 wt.% of the waste containing precious metals has to be thermally treated. This can significantly reduce the CO 2 -emissions from the gold recycling process compared with thermal processes and with conventional gold mining. KW - Bioleaching reactor, Recycling, Gold Recovery Y1 - 2022 UR - https://conferium.com/Clients/221_web/index.lasso PB - Conferium CY - Quebec (Can) ER -