In this work, energy integration of a heat exchanger network (HEN) of the Plant Refinery was carried out using the Pinch Analysis Technology through (Heat-int) software. From the operating data, the HEN data was extracted, then the heat exchanger network data were analysed through varying the Pinch temperature and the amount of hot and cold utilities were observed. Also the effects of Pinch temperature on the area of heat exchangers were done. The percentages of changing in hot and cold utilizes beside the area of heat exchangers were investigated and the percentages of utilities and area changing with Pinch temperature were done. The main problem of the exiting heat exchanger network came from cross Pinch temperature, seven heat exchangers with total energy of 183.1 MMBTU/h crosses the Pinch Point that violated the Pinch rules. Cross Pinch Point with different Pinch temperature was found to occur, so attention must be taken with these temperatures. The area efficiency of the current heat exchangers is 0.397 comparing with the ideal area with the same amount of hot utility. Retrofitting of the current heat exchangers was done by replacing some heat exchangers and adding new units. The reduced in hot and cold utilities were 6.79% and 27.9% respectively with 10.6% decreases in the area.
