Estimating utility saving by using the technique of energy situation image

•A simple energy situation image technique was presented the heat integration between processes.•This method can be easily and quickly selected the real integration between processes.•This method can be saved utilities.•This method is provided the optimal allocation between processes. The main future goal is energy-saving and emission–reduction and, thereby, the most effective way of ensuring a reduction in carbon emissions. Energy waste should be reduced from the very beginning of process production. This paper presents an estimation of utility savings by using ‘an energy situation image technique’. This technique is an extension of a simple graphical utilities targeting method for heat integration between processes (Kovac Kralj, 2012) [1] that evaluates the maximum possible heat integration between processes. The energy situation image technique chooses the best transfer allocation between hot and cold streams regarding waste heat. Therefore, the original process cannot be changed but the utilities themselves could attract savings. The grand composite curves of different processes represent optimal heat transfers between processes, and optimal transfer allocations. This method is based on pinch analysis and is very general, it can be used within new designs and within existing processes’ integrations for utility savings.