From fossil to biogenic feedstock - Exploring Different Technology Pathways for a Swedish Chemical Cluster
Paper i proceeding, 2012
This paper presents a case study of the chemical cluster in Stenungsund, Sweden. The cluster is Sweden’s largest agglomeration of its kind and consists of five companies producing a variety of chemical products. For the cluster, different options for enhanced energy efficiency and converting to biogenic feedstock are investigated. Based on these options, nine different technology pathways are defined – representing different ways to fully or partly transform the cluster into an energy efficient biorefinery. For the pathways an impact analysis is made in which the pathways are analysed and discussed from different perspectives. The results show that up to 120 MW of heat can be saved if the plants were to implement extensive heat integration measures. This is equal to ~100% of the heat currently supplied by boilers based on purchased fuels. With moderate enhancement of the heat integration, roughly half of this potential can be reached. In the fossil feedstock is to be replaced with biogenic feedstock the feedstock demand is extensive, however, the exact amount and type of feedstock depends on the technology chosen, degree of heat integration and on whether full or partial substitution is to be achieved. Full substitution of the fossil ethylene demand by ethylene based on imported bioethanol would for example demand ~1 230 kt-bioethanol/yr. If the ethanol for the ethanol-to-ethylene process were to be produced on site (based on lignocellulosic biomass), 4 725 kt-dry biomass/yr of forest biomass would be required (more than the biomass demand for four large pulp and paper mills). The results also show that the scenarios for enhanced heat integration and introduction of biogenic feedstock, to different extents, are interdependent. Furthermore, one important finding from the impact analysis is that regardless of which pathway the cluster wants to travel in their journey towards sustainable chemistry, collaboration is a key issue.