PENGARUH BUNYI ULTRASONIK TERHADAP PERTUMBUHAN BAKTERI PADA BAHAN BAKU AIR PDAM

Abstract

Water raw material of PDAM is water that is processed into processed water then distributed to public. Raw materials from river water need to be processed before being distributed to the community. Processing such as deposition of dirt and disinfectant to remove bacteria present in PDAM water raw material. However, the processing of PDAM water raw materials still uses chemicals such as chlorine gas which is used as a disinfectant of PDAM water raw material. The reduction of hazardous chemicals required the exposure of ultrasonic sounds that can reduce the number of bacteria in the water of raw materials of PDAM. However, there are only a few bacteria that can die from exposure to the ultrasonic sound.
This research was conducted by using total plate number method to know the amount of bacteria of raw material of exposed PDAM water and not exposed with ultrasonic sound. Both samples were planted on NAP medium for 24 hours with temperature 370 C.
 The results obtained from the research for the exposed sample experienced an increase in the number of bacteria, on the 1st day there were 180 colonies, the 2nd day 230 colonies, and the 3rd day 160 bacterial colonies. As for the unexposed to obtain the results of the 1st day of 169 colonies, the 2nd day of 193 colonies, days to 3- 160 colonies. This suggests that ultrasonic sounds can only inhibit the growth of certain bacteria.