Equilibrium (Aug 2023)
Optimization of Heat Transfer Area and Steam Requirement in Multiple Effects Evaporator for Concentration of Juice in Sugar Factory
Abstract
Abstract. In maintaining the existence of sugar factories that are still actively operating in Indonesia, efforts should be made to intensify sugar production and/or extensify sugarcane plantations. In terms of the intensification of the process, it is necessary to periodically evaluate the performance of process equipment, especially those that require utilities so that the process is effective and efficient. The process of making sugar passes through six stages, namely: milling, purification, evaporation, cooking, screening, and packaging as the final stage. The evaporation process is a crucial process that determines the success of the entire process because the sugar solution is concentrated from 11% to 64%. The evaporator was designed to use a multiple-effect evaporator to increase the value of steam economy. The objective of this research was to optimize the process condition that requires a minimum total cost at PT. XYZ, a sugar factory. Sugar solution /juice concentration at feed, temperature of feed, and number of effects were variables studied in this research. To achieve this goal, it was necessary to survey the sugar factory to obtain the necessary data. Furthermore, a mathematical model was compiled based on the principle of mass and heat balance and then an Excel-Goal Seek program was used to carry out an accurate optimization. To conclude, for a mass flow rate of 125,000 kg/h with a concentration of 11% sugar solution and a feed temperature of 100oC, the optimum conditions were obtained by employing a quadruple effect evaporator with a minimum annual production cost of IDR 22,090,361,779.00 at PT. XYZ. The optimum conditions obtained were as follows: total evaporator area = 2,443.81 m2, steam economy = 3.98, and steam demand = 26,028.2 kg/h. A quadruple effect evaporator is commonly utilized in sugar factories in Indonesia. Keywords: Intensification, Sugar Solution, Number of Effects, Optimization, Steam Economy