view:17331 Last Update: 2020-1-12
سیمین حق نظری، مصطفی معماریان، مرادپاشا اسکندری نسب
مقایسه مصرف انرژی روشهای القائی و معمول کارخانهای در پاستوریزاسیون شیر قبل و بعد از هدفمندی یارانهها
Comparison of energy consumption by Induction heating and usual factory methods for milk pasteurization before and after targeted subsidies
The Conventional heat pasteurization systems, due to the slowness of heat transfer to the milk, are associated with energy losses. Sometimes by increasing the temperature for the adequate pasteurization of the highly contaminated milk, it is associated with formation of the milk stone; lack of adequate heat transfer to the milk would be inconsistent with the relevant standard of health characteristics. Also, with increasing the temperature of the pasteurization, the burnt layer of milk would be thicker together with the negative impact on flavor, color and nutritional value of milk and also addition of the toxic substances to the milk. The increase in temperature will follow the more energy consumption. The other side the increase in the temperature will follow the more energy consumption. While in the induction method, the resulting electromagnetic flow has no disadvantages of conventional pasteurization of milk due to the heat transfer rate. In this study, the pasteurized milk by induction current in the device with 1600 watt of electricity transmission and 30 seconds storage time in 84 ° C and the diameter of the supporting surface of heat transfer: 23 cm (the best conditions of selected sample) was compared to the conventional method in a similar situation in terms of energy consumption and the costs were determined before and after targeted subsidies. The results showed that energy losses in both conventional and induced pasteurization methods were 46.15% and 32% respectively, and the percentage of saving energy consumption by using the induction method compared to the usual pasteurization method during the year before and after targeted subsidies, were 67% and 82.9% respectively. So, the energy consumption of induced pasteurization of milk is preferable to conventional method.