scholarly journals An Intensification of Biomass and Waste Char Gasification in a Gasifier

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1983
Author(s):  
Rolandas Paulauskas ◽  
Kęstutis Zakarauskas ◽  
Nerijus Striūgas

Gasification is considered a clean and effective way to convert low quality biomass to higher value gas and solve various waste utilization problems as well. However, only 80% of biomass is converted through thermal processes. The remaining part is char, which requires more time for conversion and in that case reduces the efficiency of gasifier. Seeking to optimize the process of gasification, this work focuses on the intensification of residual char gasification in a gasifier. For this purpose, three different types of char prepared from wood, sewage sludge and tire were examined under different conditions in a lab-scale gasification setup. Results showed that the air flux increase from 0.11 kg/(m2s) to 0.32 kg/(m2s) intensified the gasification process and the gasification rate increased from 0.8 to 2.61 g/min with the decrease of duration of wood char gasification by 72%. An additional introduction of pyrolysis gas into the char gasifier led to decreased bed temperatures, but the gasification rate increased from 0.8 to 1.25 g/min and from 2.61 g/min to 2.83 g/min, respectively, for the wood char and the sewage sludge char. Moreover, the use of pyrolysis gas coupled with air as the gasifying agent enhanced the composition of produced gas from char, and the CO2 concentration decreased by 1.68 vol% while the H2 concentration increased by 2.8 vol%.

2015 ◽  
Vol 138 ◽  
pp. 687-694 ◽  
Author(s):  
C. Guizani ◽  
F.J. Escudero Sanz ◽  
M. Jeguirim ◽  
R. Gadiou ◽  
S. Salvador

2021 ◽  
Vol 1045 ◽  
pp. 67-78
Author(s):  
Pavlo Saik ◽  
Roman Dychkovskyi ◽  
Vasyl Lozynskyi ◽  
Volodymyr Falshtynskyi ◽  
Edgar Caseres Cabana ◽  
...  

The paper represents the studies of the process of carbonaceous raw material gasification. The initial material is represented by bituminous coal of grade H with the carbon (C) content of 79.2-85.3 %. Experimental studies have been used to substantiate the parameters of combustible generator gases (СО, Н2, СН4) output depending on the temperature of a reduction zone of the reaction channel and gas flow velocity along its length. It has been identified that the volume of the raw material input to be used for gasification process changes in direct proportion depending on the amount of burnt-out carbon and blow velocity. The gasification is intensified in terms of equal concentration of oxygen and carbon in the reaction channel of an underground gas generator. The gasification rate is stipulated by the intensity of chemical reactions, which depend immediately on the modes of blow mixture supply. Moreover, they depend directly on the intensity of oxygen supply to the coal mass and removal of the gasification products.


2011 ◽  
Vol 28 (7) ◽  
pp. 1556-1560 ◽  
Author(s):  
Ji Young Lee ◽  
Sung Hoon Park ◽  
Jong-Ki Jeon ◽  
Kyung-Seun Yoo ◽  
Seung-Soo Kim ◽  
...  

Energies ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 2258
Author(s):  
Yanjun Hu ◽  
Yanjun Lu ◽  
Wenchao Ma ◽  
Linjie Wang ◽  
Haryo Wibowo ◽  
...  

Organic carbon (C) and oxygen (O) contained in sewage sludge strongly impact its thermal behavior during pyrolysis treatment. This study was aimed at getting an insight into the decomposition mechanism of organic compounds containing C and O during sludge pyrolysis using thermo-gravimetric Fourier transform infrared spectroscopy (TG-FTIR) and pyrolysis-gas-chromatography/mass spectrometry (Py-GC/MS) and helpfully improving energy conversion of sewage sludge. The temperature domains of transformation were determined and indications of the main compounds produced during each stage were obtained. Results showed that the volatile compounds that evolved after sludge pyrolysis were mainly distributed into six groups: alkenes, aromatic hydrocarbons, alcohols, aldehydes, phenols and carboxylic acids. Comparison in thermal behavior and composition of the evolved volatile compounds were observed. In the low temperature stage (<350 °C), compounds containing O–C=O accounted for the highest proportion in the evolved gas (55%). Over 350 °C, the production of C=C, –OH, and –C6H5 compounds gradually increased; but little was found of compounds containing O–C=O. Above 550 °C, as thermal chemical reaction involving oxygen-containing groups enhanced, compounds containing O–C=O and –OH tended to disappear, and an increasing amount of macromolecular polycyclic aromatic hydrocarbon was formed. Finally, the thermal transformation pathways of the oxygen and carbon-containing compounds were proposed.


2020 ◽  
Vol 142 (5) ◽  
Author(s):  
Nan Zhang ◽  
Xiaojun Ning ◽  
Guangwei Wang ◽  
Jianliang Zhang ◽  
Jian Guo ◽  
...  

Abstract The co-gasification characteristics of petroleum coke (PC), hydrochar (PS), and their blends with different ratios were studied by using thermogravimetric analysis. The Coats–Redfern model was employed to calculate the gasification activation energies of different samples. The results manifested that the gasification process of PS and blends could be classified into two stages: pyrolysis and char gasification, but for PC, there was only one primary char gasification stage. The activation energy of the pyrolysis stage was significantly smaller than the char gasification stage. In the latter stage, with the increase in the ratio of PS from 20% to 80%, the activation energy was reduced from 114.1 kJ/mol to 82.8 kJ/mol, which indicated that the PS had a significant promoting influence on the PC gasification. The research results can provide a theoretical guiding significance for the efficient use of PS and PC.


2019 ◽  
Vol 114 ◽  
pp. 07007
Author(s):  
Irina Remkunas ◽  
Igor Donskoy ◽  
Aleksandr Kozlov

In this paper, we developed a method for determining the kinetic constants of partially diffusion-controlled heterogeneous reactions in a porous sample of powder. Studies have been conducted on the experimental data of thermogravimetric analysis of carbon conversion in a stream of CO2, using a new method of processing kinetic curves, to obtain updated values of the kinetic constants under conditions where widely used models are inappropriate. Data obtained can be used for a reliable assessment of the characteristics of the gasification process.


2020 ◽  
pp. 125201
Author(s):  
María Atienza-Martínez ◽  
Nurull Nadia Binti Suraini ◽  
Javier Ábrego ◽  
Isabel Fonts ◽  
Luisa Lázaro ◽  
...  

2009 ◽  
Vol 48 (6) ◽  
pp. 3211-3221 ◽  
Author(s):  
Javier Ábrego ◽  
Jesús Arauzo ◽  
José Luis Sánchez ◽  
Alberto Gonzalo ◽  
Tomàs Cordero ◽  
...  

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