Influence of temperature and Ca(OH)2 on releasing tar and coal gas during lignite coal pyrolysis and char gasification

Effect of Iron Component on the Structural Evolution of Carbon Bonds in Hydrochloric Acid-Demineralized Lignite During Pyrolysis

“…The organic structure in lignite plays an important role in determining the products generated during pyrolysis. − It is believed that the distribution of pyrolysis products is related to the fracturing of bond structures, such as C al –O, C al –C al , C ar –O, and C ar –C al (al: aliphatic and ar: aromatic), as well as to the polycondensation of aromatics. However, the yield and composition of pyrolysis gases are affected by the bond dissociation of carbon in carbonyl and aliphatic groups. , It has been shown that the mineral components in lignite can increase the degree of disorder of aromatic structures, , promote the condensation of aromatic ring clusters, and inhibit the development of side chains, which improve the pyrolytic properties of lignite, promote the generation of pyrolysis gases, and change the yield of tar. − The catalytic effect of the iron component has also been found to be significant and is associated with the evolution of carbon bonds, which helps to improve the pyrolysis conversion rate of lignite and effectively regulates the distribution and composition of pyrolysis products. However, owing to the complex nature of different structural components of lignite, the mechanism by which the iron component affects the conversion properties of lignite during pyrolysis is not well understood.…”

“… 14 , 15 It has been shown that the mineral components in lignite can increase the degree of disorder of aromatic structures, 16 , 17 promote the condensation of aromatic ring clusters, and inhibit the development of side chains, 2 which improve the pyrolytic properties of lignite, promote the generation of pyrolysis gases, and change the yield of tar. 18 − 21 The catalytic effect of the iron component has also been found to be significant 22 and is associated with the evolution of carbon bonds, which helps to improve the pyrolysis conversion rate of lignite and effectively regulates the distribution and composition of pyrolysis products. However, owing to the complex nature of different structural components of lignite, the mechanism by which the iron component affects the conversion properties of lignite during pyrolysis is not well understood.…”

Experimental Study on Catalytic Action of Intrinsic Metals in Coal Spontaneous Combustion

“…In catalytic science, metals and their compounds are widely used as catalysts. Metals, such as Na, K, Ca, Mg, Mn, Zn, Fe, and Ni, are considered to have catalytic activity for coal pyrolysis and gasification. − Transition metals, such as Fe and Ni, and minerals, such as montmorillonite, have been shown to have a catalytic effect on organic matter. − The presence of inorganic matter can advance the peak of gas generation from organic matter in coal seams. The aim of the above research is to find a suitable catalyst to improve the yield of the product.…”

“…Metals, such as Na, K, Ca, Mg, Mn, Zn, Fe, and Ni, are considered to have catalytic activity for coal pyrolysis and gasification. 5 − 10 Transition metals, such as Fe and Ni, and minerals, such as montmorillonite, have been shown to have a catalytic effect on organic matter. 11 − 14 The presence of inorganic matter can advance the peak of gas generation from organic matter in coal seams.…”