Evaluation of demineralized lignin and lignin-phenolic resin blends to produce biocoke suitable for blast furnace operation

Metallurgical coke makers could reduce carbon emissions and material costs by introducing waste lignin in coke oven charges. Two approaches have been studied here to increase the use of lignin in the preparation of metallurgical coke: lignin demineralization with H2SO4 and lignin blending with a low...

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Detalles Bibliográficos
Autores: Castro Díaz, Miguel, Vega González, María Fernanda, Díaz-Faes González, Elvira, Barriocanal Rueda, Carmen, Musa, Umaru, Snape, Colin
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2019
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/193872
Acceso en línea:http://hdl.handle.net/10261/193872
Access Level:acceso abierto
Palabra clave:Kraft lignin
Demineralization
Torrefaction
Phenolic resin
Biocoke
Descripción
Sumario:Metallurgical coke makers could reduce carbon emissions and material costs by introducing waste lignin in coke oven charges. Two approaches have been studied here to increase the use of lignin in the preparation of metallurgical coke: lignin demineralization with H2SO4 and lignin blending with a low rank coal using phenolic resin as binder. The biocoke obtained after carbonization at 1000 °C from the hydrochar of demineralized lignin (350 °C, 6 h, biomass/water = 0.5 wt/wt) had much higher reactivity than the coke obtained from the low rank coking coal, proving that demineralization of lignin prior hydrothermal conversion is not a valid route for biocoke making. In the other approach, it was found that blends containing 70 wt% low rank coal, 24 wt% torrefied lignin (before or after demineralization) and 6 wt% phenolic resin produced biocokes with suitable mechanical strength for handling but higher reactivity than the coke obtained from the low rank coking coal alone. The microporous surface areas of the biocokes studied did not correlate with their reactivity values.