Energy utilization and saving opportunities in Textile Industries: Case study of Rivatex East Africa Ltd, Kenya

Abstract

In textile manufacturing, energy is a major contributor to production cost besides labour and raw materials. Thus, for textile industries to remain competitive, it is imperative that they develop energy management strategies for reduction of energy cost. Therefore, the main aim of this research was to assess the energy utilization in the textile factory at Rivatex East Africa Limited, Kenya and identify energy saving and conservation measures that would help reduce energy intensity and consequently lower the production cost. The specific objectives were to; analyze the energy utilization in the factory, evaluate the performance of energy utility systems and equipment, determine the potential energy savings and formulate an energy model to optimize energy utilization in the factory. Standard measurement techniques stipulated in the energy efficiency assessment manual by Association of Energy Engineers (AEE) were adopted to investigate the energy utilization and performance of high energy consuming utility systems and equipment such as compressed air systems, boilers, motors, lighting systems and steam distribution systems. Boiler flue gas analysis test, air compressor air leak test, heat loss analysis for steam distribution system, motor load assessment and load variation trends in air compressor experiments were performed. Based on established efficiency of utility systems and equipment, energy saving and conservation measures were identified. Further, a mathematical model was developed using linear programming for energy utilization and optimization. Energy utilization analysis showed that high electricity consumption occurs in spinning process 527,300 kWh/year (48%), followed by weaving process 287,700 kWh/year (26%), wet processing 247,300 kWh/year (22%) and other (boiler) 114,200 kWh/year (4%). Performance evaluation of energy utility systems and equipment found wood fire-tube boiler efficiency to be 17.35%, thermo- boiler 86.1%, air compressor 75.48% and motors power factor 0.28. The study found potential savings in electric energy to be 367,784 kWh/year, wood fuel savings 1,219 tones/year and furnace oil savings 22,275 litres/year. For the high energy consuming systems and equipment, the result indicated an overall energy cost saving potential of 31.6% with an average simple payback period of 2 years. Developed energy model displayed yearly energy cost reduction of 5.5% leading to savings of Kshs. 2 million per year. In conclusion, the results show that a significant potential exists for energy saving in textile manufacturing process and that application of linear programming models could help in identifying optimal energy saving routes in textile processing. The study recommends regular performance evaluation of high energy consuming utility systems and equipment to be conducted for early detection of energy losses to minimize energy expended in the plan