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The high use of fossil fuels in the ironmaking industry leads to CO2 emissions. This study investigates the potential of using biomass as a fuel and reducing agent for iron ore reduction. The reduction process was conducted non-isothermally up to a set temperature, followed by isothermal treatment for 60 minutes. The thermogravimetric analysis of the pellets revealed that the weight loss and CO and CO2 composition increased with temperature, indicating higher reduction reactivity. The kinetic model developed from solid-state and two-parallel reaction equations, using TGA data, showed that Fe2O3 → Fe3O4 and FeO → Fe were the most influential reactions at temperatures of 800°C and above. Furthermore, laboratory experiments analyzed the effluent gas. The results suggest that biomass is a promising alternative to fossil fuels in the ironmaking industry, reducing CO2 emissions, and enhancing the efficiency of the reduction process. [ABSTRACT FROM AUTHOR]

CFD simulation has been proven to accelerate the construction process of better biomass furnace and to find the optimum condition of biomass combustion. Optimum furnace design and operating condition can lead to better energy conversion with less pollution level. This work is aiming to formulate CFD model that can accurately predict the biomass combustion behavior inside a grate-fired biomass furnace. CFD simulation results then compared with experiment result which has been conducted using coconut shell as fuel. The distributed pyrolysis products based on atom and heat balance is utilized in the current work. The distributed pyrolysis products model gives reasonably good estimation of the volatile matter components and its composition in different pyrolysis temperature condition. Accurate prediction of the biomass combustion behavior from the proposed CFD model are depicted by high degree of similarity of several combustion parameters compared to the experimental observation i.e., temperature throughout the furnace and CO2 level of flue gas. The experimental observation give the CO2 level percentage from flue gas of 9.59±0.35 while current simulation produce the CO2 level percentage of 9.85. The relative error of temperature in furnace and CO2 level between current work and experimental observation have reached to be below 3% which is acceptable. Moreover, the proposed CFD model allows to estimate parameters which are hard to observe experimentally e.g., temperature distribution, local oxygen content, and volatile matters conversion. The established model allows further biomass combustion simulation in combination with pollutant formation which finally can be exploited to design the better furnace and better combustion condition. [ABSTRACT FROM AUTHOR]

Levulinic acid (LA) is a short-chain fatty acid with ketone and carboxylic acid group which gives it superior characteristics as a building-block chemical for producing various chemicals, such as: Ƴ-valerolactone (GVL), methyltetrahydrofuran (MTHF), diphenolic acid (DPA), delta-aminolevulinic acid (DALA), and levulinate ester. Levulinic acid can be synthesized from various kinds of biomass and its derivatives, one of which is glucose. The reaction route of glucose hydrolysis to LA generally involves intermediates such as fructose, levoglucosan, and HMF, depending on the type of catalyst used. In this study, simulation of the kinetics of the hydrolysis reaction of glucose into LA was performed by simplifying the reaction scheme from reference data. The variables studied were temperature (140-160 oC) and concentration of hydrochloric acid catalyst (0.5-1.5 M). The hydrolysis data were simulated with three different models using MATLAB 2018a. The function of ode45 was used to solve the differential equations and fminsearch tool was used to minimize the kinetic parameter values. Chang's model produces a greatest mean R2 (closer to one), which is considered more suitable than Mikola and Liang's model. [ABSTRACT FROM AUTHOR]

Lignocellulosic biorefinery is a promising alternative for petroleum refinery that has potential to meet a sustainable variety of needs in the future. One product of lignocelullosic biorefinery is levulinic acid (LA) which is a precursor for the production of many chemicals. Cellulose from lignocellulosic biomass is hydrolyzed to glucose, then hydroxymethylfurfural (HMF), and subsequently to LA. In this paper, the starting material was glucose, as a part of large LA synthesis project from biomass in the form of sugarcane bagasse. Glucose was reacted using 0.5 - 1.5 M hydrochloric acid catalyst at temperatures of 160 - 180 °C. From the experiments, it was found that the higher the temperature and concentration of the catalyst, the higher the LA yield. However, a combination of excessively high temperature and catalyst concentration will reduce the LA yield. [ABSTRACT FROM AUTHOR]