(481c) Simulation of Combustion and Gasification of Biomass Including Agricultural and Forest Residues and Pulp Mill Black Liquor Using FactSage

There is an increasing interest to convert biomass such as agricultural waste, forest residue, and black liquor solids from pulp mills into heat, power and biofuels and biochemicals.

In conventional Kraft pulp mills, the black liquor solids containing organic chemicals such as hemicellulose and lignin, and inorganic chemicals (Na2S and Na2CO3 used for pulping) is currently burnt in the Tomlinson recovery boiler for recovery of the inorganic chemicals and generation of energy via combustion. The combustion with CHP (combined heat and power) system is not very energy-efficient. Instead, IGCC (Integrated Gasification Combined Cycle) with gasification replacing combustion can bring higher efficiency and environmental benefits. In addition, part of syngas produced from gasification can be used to produce biofuels and chemicals by syngas synthesis (e.g., Fisher ?Tropsch synthesis) and conversion.

The combustion/gasification of black liquor is a very complicated process as it involves multiphase reactions including inorganic solid phases. In this study, the thermochemical software Factsage is used to simulate the combustion/gasification of biomass including black liquor solids and other agricultural or forest biomass, in order to better understand the combustion/gasification process and predict its performance or efficiency. Potential chemical emissions were also predicted to evaluate the environmental impact. The results can be useful for techno-economic and environmental analysis of the whole biomass-based biorefinery.