The increasing cost and environmental challenges associated with fossil fuels has led organizations to carry out regular energy audits and hence enforcing stringent laws to maximize and reduce cost of energy. In Nigeria, most chemical plants were built in the era when there were little or no knowledge of the concept of energy integration due to availability of cheap utility. It becomes imperative to subject such plants to various heat integration techniques to check for potential energy savings. Pinch technology is considered a straight forward, simple and efficient method for heat integration. In this research, pinch technology was used to evaluate the heat exchanger network of the Butene-1 unit of the Indorama Petrochemical Company Eleme for potential energy savings. The unit was simulated using ASPEN HYSYS (V.8.6). Process data were extracted from the simulation results and supplied to HINT (V.2.2) software for analysis. The minimum utility requirements and Pinch Temperature (57oC) were obtained from the composite curve, cascade diagram and grand composite curve. The proposed retrofit heat exchanger network revealed a hot and cold utility requirement of 1064.05kW and 204.85kW respectively, compared to the hot and cold utility requirement of 1113kW and 364.46kW respectively of the existing HEN. This showed an energy savings of 4.4% for cold utility and 43.79% for hot utility. Cost evaluation of the proposed HEN was carried out, with a total annual cost of $1,971,977.267.
Keywords: Butene-1, Energy Integration, Pinch Technology
