Industrial case studies

A short review of the CA process is given before proceeding with the applications of the technique to several industrial case studies. The three key stages of CA are shown in Figure 2.24 within the simplified process of assessing a design scheme. 

Mass balances of four case studies were evaluated. Additionally, an LCA is considered for the last case study. Case study 1 and Case study 2 are academic and include a comparison between alternative synthesis protocols. In the industrial Case study 3 and Case study 4, a comparison of the steps of a scale up was possible. 

Mass indices and environmental factors (equations (5.1) and (5.2)) have been introduced in Section 5.1. For confidentiality reasons, neither chemical names nor exact quantities are specified concerning the industrial case studies. Instead, masses are expressed relatively to input amounts at the laboratory scale. The imit (kg kg ) expresses how many kilograms of substance are needed to produce one kilogram of product. Abbreviations used in captions of the figures are explained in Box 5.2. 

Alvarez, N., Daufin, G., and Gesan-Guiziou, G. (2010). Recommendations for rationalizing cleaning-in-place in the dairy industry Case study of an ultra-high temperature heat exchanger. /. Dairy Sci. 93, 808-821. 

Problem description Figure 2.10 is the flowsheet for the industrial case study used to illustrate the application of the SSN based approach. Figure 2.11 is the corresponding SSN. 

Table 2.8 Scheduling data for the industrial case study...

The industrial case study presented in this section is taken from the petrochemicals industry. The project is in the design phase and as such the design model will be used to determine the design which leads to the minimum capital cost, while using the PIS operational philosophy. For secrecy reasons the example has been modified and the names of the raw materials and products have been changed to the generic form. 

The second mathematical formulation presented, is a design model based on the PIS operational philosophy. This formulation is an MINLP model due to the capital cost objective function. The model is applied to a literature example and an improved design is achieved when compared to the flowsheet. The design model is then applied to an industrial case study from the phenols production facility to determine its effectiveness. The data for the case study are subject to a secrecy agreement and as such the names and details of the case study are altered. 

The facility considered in the industrial case study is a pharmaceuticals production plant, which produces a wide variety of consumer products, e.g. shampoos and creams, and female sanitary products. The plant was chosen due to the fact that production was carried out in batch mode. In a year the plant uses on average 90000 m3 of water, with approximately 60-70% of this discarded as effluent. An on-site treatment facility pre-treats wastewater produced from the site to a level where the water can be discharged into the municipal water system. 

The industrial case study was centred on the four mixers found in the toiletries area, as described above. Due to the multiple products found in the area, the residues within the system were not all the same (Table 6.7). This coupled with compatibility considerations between the various contaminants in the wastewater meant that the multiple contaminant wastewater minimisation methodology was suited to the problem. 

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