Experimental Investigation of Energy Efficiency and Saving Opportunities for an Industrial Boiler in Process Industry: A Case Study of a Textile Manufacturing Industry in Kenya.
- March 16, 2022
- Posted by: rsispostadmin
- Categories: Engineering, IJRIAS
International Journal of Research and Innovation in Applied Science (IJRIAS) | Volume VII, Issue I, January 2022 | ISSN 2454–6194
Isaiah kimutai1 and Paul Maina1
1Department of Mechanical & Production Engineering, Moi University, Eldoret, Kenya
Abstract: Boilers are widely used in process industries to generate steam and hot water. Boiler systems represent a significant portion of total industrial energy use. A slight improvement of boiler efficiency reduces production cost which is necessary for textile industries especially in developing countries to remain profitable and competitive both locally and globally. This paper presents performance assessment of industrial Wood fire- tube boiler used in a textile industry. Performance test was conducted to determine actual performance and energy efficiency of the boiler by flue gas analysis of various flue gas samples exiting the boiler installation. The results displayed poor performance of the boiler with overall efficiency of 17.35% against design efficiency ranging between 75-77%.The major heat losses of the boiler found include dry flue gas loss (58.97%), heat loss due to moisture present in fuel (11.48%) and heat loss due to evaporation of water formed due to H2 present in fuel (9.61%). Based on the results high energy potential lies on excess air control and reduction of moisture content present in wood fuel.
Keywords: Boiler, Flue gas, Energy efficiency, Energy saving opportunities, Heat loss, Kenya.
1. Introduction
Textile manufacturing is an energy intensive process starting from yarn making in spinning through to woven fabric treatment in wet processing. Energy remains one of the main costs of production besides raw material and labour in textile industry. Research shows that in textile industry energy cost range from 15% – 20% over the production cost and it stands next to raw material cost [1]. The rising energy costs demands adoption of opportunities that lower production cost without affecting production yield and quality of products by industrial plants in order to remain competitive both locally and globally. There are various energy saving opportunities that exist in textile industries, many of which are cost effective. However, even cost effective options often are not implemented in textile plants mostly because of limited information [2].Studies show that with proper energy management,energy cost savings of 5-15 percent can be obtained quickly with little to no required capital expenditure when an aggressive energy management program is adopted. Usually savings of 30 percent is common, and savings of 50, 60, and even 70 percent have been obtained. These savings all result from modifying existing equipment and adoption of new technologies. For most manufacturing, industrial and other commercial organizations energy management is one of the most promising profit improvement and cost reduction programs available today [3].
Boiler system is one of the high energy consuming utility systems employed in textile processing besides motor system, lighting system, compressed air system and steam distribution systems. Boiler system steam generation accounts for 30% of the total industrial energy use [4]. These systems provide thermal energy in the form of steam and heat needed for process heating and production of hot water for process reactions, drying and washing. In the combustion chamber of the boiler, fuel is burnt and heat produced in form of hot flue gas is transferred via boiler tubes to surrounding water by convection.As the hot flue gas transfers heat to water, about 10-30% of heat energy is lost in the process. The temperature of flue gas exiting the boiler typically ranges from 150-250oC. Other heat losses from a boiler are radiation, blow-down, fly ash and bottom ash losses. In order to run a boiler plant at its optimum efficiency, it is necessary to identify the major source of energy loss and recover the energy which is wasted [5].
