In this issue of Green Indicator we are looking at the possibilities of integrating biomass gasification in different current industries, such as chemical pulp mills, oil refineries, steel plants etc. And in today’s CatScan alternative production of ammonia by circumventing the equilibrium with the use of cold plasma is discussed.

/Andreas Leveau

Industrially integrated biomass gasification

Over the last decade, a large number of studies on industrially integrated gasifiers for production of biofuels have been published. These studies comprise different types of gasifiers (fluidized bed, indirect and entrained flow) integrated in different industries for the production of various types of chemicals and transportation fuels such as SNG, FT-products, methanol and DME.

Integrating biofuel production processes in existing industries may result in a number of technical, energy-related and economic benefits. For instance, large feedstock handling and logistical advantages can be obtained by integrating biofuel production processes in existing forest industries. Gasification of black liquor can be applied in chemical pulp mills, where it can also be possible to replace the bark boiler with a biomass gasifier for syngas production. Biofuel production processes can also be co-located with other process industries with a steam or hot water demand, such as sawmills or biomass-based combined heat and power plants. In those plants, biomass handling and logistical benefits may also be obtained. Oil refineries and steel plants are also interesting from the point of view of integration. The former due to already existing downstream processes (distillation columns, cracking processes, etc.) and the latter due to the possibility to utilize energy-rich excess off-gases from steel making, which can be used for co-synthesis with biomass based syngas.

However, it is difficult to compare the results of these studies systematically since they most often have different system boundaries, production capacities etc., and since for example efficiencies are often calculated using different methodologies and standards. This makes comparisons of system efficiencies between different integrated biorefinery concepts and studies difficult (or unfair), even for studies that are very similar to each other. Despite this, the results from various techno-economic studies made on the subject of industrially integrated biomass gasification indicate that this could be a promising opportunity for different industries to increase their overall system efficiency.