Management of Water Utilization for Dyeing Process in Carpet Production Industry Using Clean Technology Approach

Abstract

Dyeing process is one of the main processes in carpet production industry which highly impacts to environment compared other processes. This is because dyeing process spends a large amount of water and resources. This study aimed to manage water utilization for dyeing process using clean technology approach. The result showed that in the case study plant, water consumption of 93.09 liter per day (174 liter per kilogram-product) was found. Based on Ishikawa diagram to evaluate loss, 3 potential alternatives including 1) improving bath washing process by box installation, 2) utilizing condensed steam loss, and 3) reusing water for scouring process was chosen. For the first option, improving bath washing process was to install a box to reduce space of dyeing bath resulting in decrease washing water consumption. The flow simulation using SOLIDWORKS 2014 was performed. The result indicated that after box installation, water flow type was vortical motion with similar water velocity compared to that before the box installation. For the second option, utilizing condensed steam loss was to directly reuse the loss water as raw water instead of tap water. Based on technical feasibility study, it was found that the loss water quality was comparable to raw water. Therefore, the loss water could be used as raw water for dyeing process. The last option was to reuse water during scouring for continuous material washing process. Since the reused water quality was similar to soften water used for scouring, this option (direct water reuse in the process) did not need any added equipment. For all mentioned options, water and chemical consumptions reduced for 1,728.94 cubic meter per year and 958.2 kilogram per year, respectively. Total saving cost was 238,803 baht per year.