Abstract:
This research applies design of experiments technique to study the effect of three process parameters which are flow rate of steam, percentage of valve opening of the pressure cylinder, and percentage of glycerin in neat soap on the production cost of soap. The concerned costs are cost of raw materials and cost of yield loss. In addition, this research determines the new setting of these three parameters that reduce the total cost, while quality is not affected. The quality measures are soap hardness and soap weight loss due to evaporation of moisture, which is governed by the laws of commerce. It was found that when using the steam flow rate at 1,279 kilograms per hour, the percentage of valve opening of the pressure cylinder at 80 percent, and the percentage of glycerin in neat soap at 3.5 percent, the total cost of soap production could be saved by 13.3 million baht per year compared to the cost of production in 2554. The new setting did not affect the hardness of the soap and the soap weight loss due to evaporation of moisture.