The article presents mathematical description of gas-solid flow reactor and its solution with C++ BzzMath library. This work is illustrating the way of developing the control system of flow reactor with PI/PID controller. Quasi linear regions of output depend on input and disturbance signals were found and several conventional and modern tuning techniques were applied to provide the robustness and performance trade-offs. The system stability was checked for robustness in different regimes (quasi linear and non-linear).
