Total Waste Water at Rice Washing for Rice Cooking, its Composition and Cost Analysis
Washing water volume of rice for cooking and rice weight for one person per meal in one household were surveyed for confirming pollution by the washing water and total losses by rice washing procedures. The mean size of a family was 4.64 persons and the mean consumption weight of rice per capital per meal was 138.43g. It is used 0.782 L of water for washing the rice per capital share. The washing water of rice was composed of 0.32% of total solid, 0.11% of soluble solid and 1.65% of solid loss to rice, and COD and BOD of it were 2.400 and 3.564 ppm respectively. Based on total population in Korea, 41 miliion, excepting age below 4, total cost for washing water of rice summed up about 1,495 billion won including 8.8 billion won for tap water cost, 11.7 billion won for waste water treatment, and 129 billion for solid loss of rice.