Estudo sobre a extração de lignina do licor negro, seu impacto no processo de recuperação e geração de energia e seu potencial uso em novas aplicações

Abstract

Global competitiveness encourages markets to seek more and more capacity and efficiency in their processes. The paper and pulp industry has sought the best energy efficiency and cost reduction in its processes. In this scenario, the Kraft pulp process has been developed to improve the profitability of plants through the recovery of chemicals. The recovery process is made from the black liquor which is a by-product of the wood cooking process. Black liquor is used for burning in the recovery boiler. This combustion, besides enabling the chemical recovery, also generates steam to produce energy to the industry. Cellulose plants today are self-sufficient in energy generation, and can even sell the surplus of what is consumed. However, in addition to using this liquor as boiler fuel, another way to exploit the surplus energy and process residues in a modern pulp mill is by extracting lignin from this black liquor. Although lignin extraction process and modification are relatively recent and in development, the extracted lignin can be used as biofuels, replacing the need for fossil fuels in various industries, as well as raw material for several other applications. This study describes the process of lignin extraction from black liquor, its implication in the energy generation process and its new applications. Based on this learning, this paper presents a discussion about the opportunities of these new applications, as well as the respective restrictions on their use.