Indefinite integration, application

The constant C is the constant of integration introduced in the applications presented in Chapter 1 [Eqs. (1-20) and (1-24)]. There it was indicated that the determination of this constant requires additional information, namely, the initial or boundary conditions associated with the physical problem involved. Integrals of this type are, therefore, called indefinite integrals. 

Another important application of lumping is the lumping of continuous mixtures where an indefinitely large number of species are involved in a reaction [115-125]. Such techniques will be useful especially in processes which involve complex hydrocarbon mixtures such as petroleum feedstocks etc. The discrete system is then represented by a continuum and the lumping by an integration rather than a summation over the original variables. 

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