Pneumatic control for sustainable compressed air systems : multi-criteria optimisation for energy efficient production

Abstract

Compressed air is widely utilised in manufacturing processes across all industries due to numerous advantages associated with its use. However, the energy efficiency of compressed air generation is often very low, making pneumatic systems one of the most expensive processes in a manufacturing facility. Additionally, compressed air leakages further artificially increase the demand and decrease their efficiency and productivity. This study focused on identifying the effects of pressure and flowrate regulation on the energy efficiency and productivity of a pneumatic automation system. By combining these two control strategies, a reduction in air consumption was achieved while also maintaining the system’s cycle time in order to minimise productivity loss. The assessed system included various leaks of different sizes at different locations. When implementing pressure regulation, a reduction in air consumption of up to 22 per cent was achieved. As expected, this also resulted in an increase in cycle time of up to 19 per cent, which was then reduced to 7 per cent by regulating the system’s flowrate at the end of use. Multi-criteria optimisation was subsequently employed to identify the optimal control parameters for a balanced effect on both air consumption and cycle time, affecting energy efficiency and productivity, respectively.