New Sustainable Chemicals and Energy from Black Liquor Gasification Using Process Integration and Intensification

In the areas of chemicals and allied products and energy process engineering, it is of particular interest to design processes with low‐energy requirements (energy intensive) (preferably renewable materials, e.g. biomass) and the use of minimum raw materials or use of a by‐product as feedstock (materials intensive) and minimum number of equipment (i.e. lean manufacturing). This is the basis from which the area of PI arises. The main objective of PI is to propose production and manufacturing processes in plants as small as possible and with low total energy, materials, water, and other resources. To reduce the size of plants, the scope is reducing the size of equipment or the number of operations in the processes, or using multifunction within the process is must. Since energy requirements of industrial processes are usually satisfied with steam, for which production is necessary to burn some kind of fuel (usually fossil fuels), by reducing energy requirements a direct reduction on environmental impact (e.g. greenhouse gases, oxides of carbon, nitrogen and sulfur, and particulate matter). In this extended case study, black liquor, a by‐product of wood‐pulping process, is utilized to make chemicals and biofuels, in particular methanol, dimethyl ether, and syngas. Different feedstock, use of by‐product and alternatives and principles of PI are commented (Gómez‐Castro et al. 2016).