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highlights the robustness of process models in predictions of product quality (H 2 /CO) and yield (H 2 +CO). In fluidised bed reactors, the interaction between the solids and gas is very important to enhance contact between reactants and maintain a consistent thermal profile throughout the bed. The commercial CFD software, Barracuda Virtual Reactor, developed by CPFD Software, is a robust tool used throughout industry to study these complex fluidised bed systems. The CPFD models help provide insight into the fluidisation behaviour under various conditions and verify key design and scale-up considerations during commercial product development. Figure 4 shows sample results for key process variables, which are used to generate an insight into reactor performance and scale-up. SunGas’ S1000 product is an integrated system consisting of key components engineered to provide excellent performance (see Figure 5 ). The process starts with drying biomass to the required moisture content. The dried biomass is fed into a fluidised bed gasifier, reacting with steam and oxygen at 850°C. Inside the gasifier, biomass undergoes pyrolysis, breaking down into volatile gases and char. The char reacts with steam and oxygen to produce syngas, a mixture of hydrogen, carbon monoxide, carbon dioxide, methane, and other trace gases. The fluidised bed ensures thorough mixing and heat transfer, promoting greater than 95% conversion of the carbon in the feedstock. The SunGas’ integrated solution for decarbonisation Figure 3 SunGas process validation parity plots for woody biomass feedstocks
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resulting syngas is cleaned of impurities and can be used for power generation or processed into advanced clean fuels and chemicals. In the quest for advanced clean fuels, one of the challenges is the heterogeneous nature of feedstocks, requiring tailored pretreatment for consistent quality. High moisture content reduces conversion efficiency, and impurities like ash and sulphur require additional treatment and processing steps. Reliable feedstock supply chains and economic viability are also concerns, needing robust logistics. SunGas’ S1000 system, designed to process woody residues from forest thinnings, effectively addresses many of these challenges. These residues contain low levels of ash and other contaminants (such as sulphur and chlorine), which minimises the need for extensive feed pretreatment. After chipping, the only treatment needed is drying the chips to target moisture content, which is accomplished by low-level heat integration between the S1000 and wood dryers, enhancing overall process efficiency. The S1000 feeding system is designed for wood chips that are already widely used in the pulp and paper industry and biomass power plants. Thus, much of the production and transportation Figure 4 Syngas component profiles and solids distribution results from CPFD model
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