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A popular method to recycle plastic wastes is pyrolysis, where oil, gas and char can be produced. These products can be utilized as fuels because they are basically hydrocarbons. The research investigates char properties, including their performance as fuel briquettes. There are 13 char samples from PE (Polyethylene) pyrolyzed at temperatures of around 450 oC, with and without a catalyst. Some of the samples were obtained from PE mixed with other types, such as Polystyrene (PS), Polypropylene (PP), Polyethylene Terephthalate (PET), and Others. Char properties, such as moisture, ash, volatile matter, and fixed carbon contents, are revealed from the proximate analysis, whereas calorific values were measured with a bomb calorimeter. Briquettes are made by mixing 4 g of char with 0.5 - 1 g binder. Briquettes are hollow cylinders with an outer and inner diameter of around 1.75 cm and 0.25 cm, respectively. Combustion is carried out in a furnace with wall temperatures of about 230oC and a constant air velocity of 0.7 m/s. Five out of 13 char briquettes are not feasible because they melt during combustion. Briquettes made from 100% PE wastes burn in substantially shorter duration than those from mixed plastic wastes. Char #1 and #5 are excellent due to their highest energy release, whereas #10 show the worst performance. [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]