In the present work the sequential code ECLIPSE is used to perform an energy analysis of an entire industrial process*a coke production plant*aiming its characterization and optimization in terms of energy requirements and environmental impact. The code is validated by comparing its results against existing experimental data acquired at the above-referred plant, for the present operating conditions. Agreement is observed to be rather good, as the maximum relative errors between the ECLIPSE predictions and the actual values are 9.2, 9.7 and 8.7 per cent, respectively, for mass #ows, temperatures and pressures. Moreover, those errors occur only once and at di!erent streams, the vast majority of the relative errors for the remaining streams being below 1.0 per cent. In order to optimize the process both as far as energy and environmental aspects are concerned, alternative or new unit operations are suggested and are included in the production #ow sheet or added to it and the entire new processes are simulated. More speci"cally, the better sealing of the coke ovens doors eliminating 80 per cent of the volatiles escape, the recovery of the lost sensible heat in the coke extinction operation and the restart of the 10 non-productive coke ovens would yield remarkable energy savings*losses would reduce from 46 440 to 9260 kW, apart from the environmental bene"ts emerging from the elimination of the volatiles escape to the atmosphere. In addition, for the coke gas cleansing sub-process, the substitution of the stripping process in the column distillation by a separation process, making recourse to a reverse osmosis installation, together with the operation setting of the ammonium destruction oven at a more convenient temperature, would allow both for energy savings of 66 per cent and a substantial reduction in both gaseous and liquid emissions, namely naphthalene, ammonia, nitric oxides and sulphur oxides. The improvements attained are noticeable and encouraging. Therefore, ECLIPSE proved to be an adequate tool for global industrial processes simulation, analysis and optimization, in spite of some limitations exhibited by the code in simulating detailed complex physical phenomena, such as combustion or coal distillation.