Browsing by Subject "Biomass"

Now showing 1 - 2 of 2

Access status: Open Access ,
Comparative study of grass pyrolysis over regenerated catalysts: Tyre ash, zeolite, and nickel-supported ash and zeolite
(2024) Jerzak, Wojciech; Sieradzka, Małgorzata; Wądrzyk, Mariusz; Magdziarz, Aneta
Wydział Inżynierii Metali i Informatyki Przemysłowej
This paper presents investigations on catalytic and non-catalytic grass pyrolysis conducted at 500 °C using two reactor scales: a micro-scale reactor and a laboratory fixed-bed reactor. Four catalysts were employed in the catalytic pyrolysis process: car tyre ash, commercial zeolite mordenite-sodium, nickel supported on ash, and nickel supported on zeolite. The use of catalysts reduced the production of oxygenates and promoted the formation of gaseous compounds, with the most pronounced effect observed for nickel supported on zeolite. Catalytic pyrolysis produced chars with yields that were higher than those of the non-catalytic process. The coking behaviour of the spent catalysts was evaluated by analysing carbon content, with the highest content (3 wt% C) obtained for ash after the first cycle. In the second cycle, the deposited carbon content decreased for all catalysts. Furthermore, the employment of catalysts was shown to promote the production of hydrogen, methane, and other hydrocarbons in pyrolysis gas. The higher heating value of the pyrolysis gas was the highest at 21.1 MJ/m³ when the ash catalyst was first used for pyrolysis. Reusing the pyrolysis catalysts slightly reduced the heating value of the gas to 20.3 MJ/m³ over ash and 20.6 MJ/m³ over zeolite.
Access status: Open Access ,
Potential of products from high-temperature pyrolysis of biomass and refuse-derived fuel pellets
(2024) Jerzak, Wojciech; Mlonka-Mędrala, Agata; Gao, Ningbo; Magdziarz, Aneta
Wydział Inżynierii Metali i Informatyki Przemysłowej
The management of energy contained in waste is an important research topic. Among many high-energy wastes, pellets are produced from refuse-derived fuels (RDF) and lignocellulosic biomass. This study investigated hightemperature pyrolysis (800 °C) of biomass and RDF pellets. Experiments were conducted in two reactors: i) on a microscale (thermogravimetric analysis) and ii) on a laboratory scale (fixed-bed reactor) to investigate the yields of the products (char, liquid fraction, and gas) and to characterise products toward their further application. The RDF char contained less carbon than the material before pyrolysis. The carbon content of the biomass char was 90%, almost twice that of the raw material. The biomass and RDF chars were chemically and physically activated to increase their specific surface areas. The chemically activated biomass char had a sorption capacity of 156.2 mg/CO2 at 25 °C and 0.1 MPa. The kinetics of CO2 sorption were also examined, and the maximum uptake was observed after 2–3 min. The higher heating value of the liquid phase, including the organic condensed phase, was 28.6 and 25.8 MJ/kg for pyrolysis of biomass and RDF pellets, respectively. The pyrolysis gas composition was analysed separately for the heating and isothermal processes. Due to the high CO, CH4, and H2 contents, the gas from the heating stage was characterised by a much higher heating value.