Downstream processing, influencing factors

Besides the production of L-lactic acid, the fermentation process can simultaneously produce various other metabolites such as acetic acid, f umaric acid, ethanol, malic acid, etc. However, the amount of these metabolites can have a significant influence on the downstream process and the quality of the L(+)-lactic acid produced (Wang et al., 2005). Fumaric acid is the main by-product and its accumulation is affected by many factors,... 

The objective of process development in industrial crystallization is the minimization of the Idnetically determined part of the impurities in the target product to achieve a purity as high as possible. The factors influencing the final product purity relate to the process conditions comprising both crystallization and downstream processes. 

Understanding and modelling the effects of various factors governing the stability of two-phase dispersions systems is vital since it influences the process design of appropriate chemical reactors, their subsequent downstream processing, storage and transportation. Central to this is the ability to make direct measurement of the sedimentation kinetics of such dispersions in an on-line manner. 

Boiling range also is used to identify individual refinery streams—as an example will show in a later section concerning crude oil distillation. The temperature that separates one fraction from an adjacent fraction will differ from refinery to refinery. Factors influencing the choice of cut point temperatures includes the following type of crude oil feed, kind and size of downstream processes, and relative market demand among products. 

There are a large number of different types of fermentation processes that are used commercially, which are selected based on several different factors.19 21 Depending on the strain to be used, the fermentation could be aerobic or anaerobic, and the desired product could be either the biomass itself or a metabolite or polymer produced by the biomass. The kinetics of product formation, whether growth associated or nongrowth associated, also influences the process. Often procedures downstream of the fermentation unit operation have a major control of the overall process and determine how the fermentation is conducted. 

Besides regulations, another relevant factor influencing the behaviour of firms is represented by the market pressure, and the greater attention that consumers direct towards the enviroiunental impact of products and production processes. In the chemical sector the pressure from public opinion and from the market have both a direct and an indirect influence, through the supply relationships . Indeed, chemical firms supply many intermediate products to downstream industries, which in turn introduce chemical compounds in their final products. The environmental performance of end products depends on the environmental performance of the entire production line. Therefore, the capability to prevent pollution and the formation of wastes by the chemical industry induces a reduction of pollution in the whole economic system. 

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