Exergy Based Sustainability Analysis of Steam Generation and Utilization in Nigerian Pharmaceutical Industries

Abstract

Exergy based sustainability analysis of steam generation and utilization in Nigerian pharmaceutical industries has been presented. Two pharmaceutical plants were considered which include JUHEL and DANA plants located in Awka, Anambra state and Minna, Niger state, respectively. The objective of the study is to perform a comprehensive energy and exergy analyses of steam boilers for JUHEL and DANA pharmaceutical industries and determine the utilization efficiency and sustainability index of the process heat at different operating conditions. The exergy of the component system was evaluated and the analysis done using an Engineering equation software (EES). The results obtained show that the fuel utilization efficiency varies from 30.4 to 67.2 % for energy efficiency and 17.5 to 55.6 % for exergy efficiency for JUHEL plant. Similarly, the FUE for DANA plant vary from 32.4 to 68.9 % for energy efficiency and 16.6 to 54.9 % for exergy efficiency. The environmental effect factor (EEF) shows increasing trend for all increasing values of ambient temperature. The environmental effect factor decreases slightly at low air mass flow rate (AFR) for both plant. Though EEF values for Dana plant are slightly higher by about 0.01% at higher AFR. The sustainability index fluctuated between 0.1970 and 0.209 for the two plants. The JUHEL plant recorded slightly improved values of waste exergy ratio (WER) of 0.02 % at higher AFR. The study shows that the variations in these indicators is due to the small difference in the design operating data. The study also suggests a retrofitting of the existing pharmaceutical plants and a time series analysis will be necessary to show how the plant’s irreversibilities change with time for proper optimization.

Keywords: Energy, Exergy, Sustainability Index.