Exemplary chemical supply chain with two sites

Imbalances are compensated either by heating with H2 or by external supply from producers of industrial gases nearby both sites.  

Steam crackers produce a fraction of O4 hydrocarbons which is a mixture of differently structured chemicals all containing four carbon atomsf In this mixture, 1,3-Butadiene is the largest sub-fraction with the highest applicability in downstream processes. Therefore, this sub-fraction is extracted by rectification. The remaining sub-fractions of C4 hydrocarbons (so-called rafSnatej is sold to the market ex factory. 

At both sites imbalances of the processed intermediate chemicals occur when all plants produce at full capacity. Unbalanced intermediate chemicals are indicated by a coloured storage symbol when inter-site transports are possible. Correspondingly coloured arrows between both sites indicate the direction of the product flow. Table 4-4 guantifies these imbalances and provides an overview on the chemicals associated storage capacities. 

A net demand (indicated by negative values in the balance columns in Table 4-4) f intermediate chemicals has to be satisfied by product flows between both sites or from 

Sources of disturbances considered in this example are categorized in three classes. First, the production plants are stochastic transformers, i.e. the transformation processes are modelled by stationary time series models with normally distributed errors. The plants states are modelled by Markov models as introduced before. The corresponding transition matrices are provided in the appendix in Table A.15 and Table A.16. Additionally, normally distributed errors are added to simulate the inflovj rates with e N (O, ) where oj is the current state of the plant. 

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Figure 4.8 Exemplary chemical supply chain with two sites...

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