Input-Output Analysis and Linear Programming with Purchasable Intermediate Products and Joint Final Products

Abstract

Raistrick Ltd is a division of Genco PLC, and is concerned with the manufacture of products for the brewing industry. Specifically, it manufactures as joint products a very concentrated yeast additive called Pirco and an enzyme called Urquase. This manufacturing activity involves three processes, numbered I – III. Processes I and II each give rise to a single product (Products I and II respectively). Process III is the final process, from which both Pirco and Urquase emerge, manufacture taking place in the fixed ratio of 0.8 kilograms of Urquase produced for every kilogram of Pirco. The chemical processes involved are heavily dependent upon the use of catalysts, and the flow of product through them can be depicted as in Figure 7B.1.