The M-PROJECT implements a methodology for tile efficient generation of static and transient process models and their subsequent numerical solution. The knowledge-based hierarchy of the M-PROJECT framework is composed of the Material_Model, the Abstract_Constraint_Definition, the Specific_Problem_Instance and the Generic_Solver. The methodology enforces the principle of hierarchical decomposition of balance envelopes with increasing degree of detail without discrimination between design variables and process parameters. A tree of Abstract_Constraint_Definitions represents generic formulations of mass and energy conservation, while the Specific_Problem_Instances are specialized process models derived by selecting a subset of the relations in parallel with a deliberate registration of design variables. While these process models may differ in scope, number of equations as well as distribution of parameters and variables according to their respective design objectives, their common descent of the underlying tree of Abstract_Process_Definitions and utilization of the abstract modeling language of the Material_Model ensure consistency and robustness against changes of the process flowsheet. The presented methodology has been successfully applied for the design of steady-state and dynamic industrial processes as well as for on-line data reconciliation.