A one-dimensional home-made mathematical model of coke-making process in the heat-recovery (HR)/non-recovery (NR) coke oven has been developed. The model includes a series of sub-models described in associated publications (Buczynski a al., 2016 [1-4]). In this paper (Part V) a different approach for predicting the carbonization process is proposed. The coking-bed sub-model presented in Buczynski a al. (2016) [2] is based on a direct procedure (forward calculations) and the moving boundary technique. This approach is difficult to implement and calculations are time consuming. Moreover, the model is valid for one particular coal blend only. This paper describes the coking-bed sub-model based on an inverse problem formulation that adjusts itself to represent carbonization of particular charge. The new coking-bed sub-model contains completely different algorithm for predicting time-dependent processes such as: moisture evaporation and condensation, formation and condensation of tars.