Performance Enhancement of Sugar Mill by Alternate Cooling System for Condenser

Abstract

Agro industry plays a crucial role in the industrialization process of developing countries. Sugar industry is second largest agro industry in the world. In sugar manufacturing plants there are various processes for production of sugar i.e. extraction of juice, clarification, evaporation, concentration of juice, forming and separating crystals etc. These processes consumed energies in the form of mechanical energy, electrical energy and heat energy. So there are various sources of waste heat in sugar factory i.e. waste heat from hot flue gasses, hot water from evaporative body and boiler blow down. The large amount of waste heat passes from various devices of sugar factory causes decrease in the efficiency of sugar plants, and also increase the "Global Warming" which is very dangerous for our environment. The present cooling system for condenser is inappropriate & hence decrease vacuum in evaporators and pans. This will increase the boiling point temperature of juice. The proposed cooling system gives solution of both problems. The most important source of waste heat i.e. hot flue gases are use to run absorption chiller. The absorption chiller gives better cooling system for condenser. There will be improvement in condensation of vapour in condenser which will cause increase vacuum in evaporators and pans thereby reducing boiling point temperature of juice. This reduced boiling point temperature of juice requires less amount of steam for boiling, ultimately saving of bagasse and fuel economy can be attained. Thus this arrangement can be treated as the efficient method of utilization of waste heat for cooling condenser water in sugar factory thus saving further depletion of natural resources like coal, petroleum or else increasing its availability to other important processes and one can hope that the "waste heat recovery" may play an even greater role in the industrial development in this new millennium. Key word: Boiling of juice, bagasse yields, crushing, scrubbing system, vacuum measurement, gur. Introduction: The sugar industry processes sugar cane and sugar beet to manufacture edible sugar. More than 60% of the world"s sugar production is from sugar cane, the balance is from sugar beet. Sugar manufacturing is a highly seasonal industry, with season lengths of about 6 to 18 weeks for beets and 20 to 32 weeks for cane. Approximately 10% of the sugar cane can be processed to commercial sugar, using approximately 20 cubic meters of water per metric ton (m3/t) of cane processed. Sugar cane contains 70% water; 14% fiber; 13.3% saccharose (about 10 to 15% sucrose), and 2.7% soluble impurities. Sugar canes are generally washed, after which juice is extracted from them. The juice is clarified to remove mud, evaporated to prepare syrup, crystallized to separate out the liquor, and centrifuged to separate molasses from the crystals. Sugar crystals are then dried and may be further refined before bagging for shipment. In some places juice is extracted by a diffusion process that can give higher rates of extraction with lower energy consumption and reduced operating and maintenance costs. For processing sugar beet (water, 75%; sugar, 17%), only the washing, preparation, and extraction processes are different. After washing, the beet is sliced, and the slices are drawn into a slowly rotating diffuser where a countercurrent flow of water is used to remove sugar from the beet slices. Approximately 15 cubic meters (m 3 ) of water and 28 kilowatt-hours (kWh) of energy are consumed per metric ton of beet processed. Sugar refining involves removal of impurities and decolonization. The steps generally followed include, affixation, melting, clarification, decolonization, evaporation, crystallization, and finishing. Decolonization methods use granular activated carbon, powdered activated carbon, ion exchange resins, and other materials. 1 Methodology