Overall performance of steam system used in garment industries in Bangladesh: a case study–based approach

Abstract

The fabric or garments production activities starting from raw material preparation to the finishing process are energy-intensive. Steam generation and distribution system is part of all the major processes involved here. Therefore, this study aims to assess the overall performance of the steam system used in the textile or garment industry in Bangladesh. The quantity of heat loss through different sources both at steam generation and distribution unit was computed. The amount of in-process heat energy consumption was also determined. Current practices in steam system management were investigated, and opportunity for improvement was addressed. Finally, the genetic algorithm approach was used to optimize the process parameters of steam generation unit thermodynamically. The average efficiency of the steam generation units used in the fifteen studied factories was found 76%. The dyeing and ironing processes were found as the most heat energy–intensive process. Among the sources of heat losses, maximum loss was found occurring through the dry flue gas during steam generation. At distribution unit, most heat is lost through the steam line and in-process distribution. Based on the analysis, daily 694 GJ heat passes away through a steam system resulting in 13 tons and 31 tons of fuel wastage and greenhouse gas emission, respectively. Considering the occurring losses, the remedial measures were focused on excess air and stack temperature control, improvement in boiler operating condition, steam leakage and trap maintenance, insulation enhancement, etc. Moreover, by optimizing the thermodynamic process parameters, it is possible to increase energy efficiency by almost 3.0%.