THE EFFECTIVENESS OF SOLENOID MAGNETIC FIELDS TO REDUCE PRECIPITATION LEVELS OF CACO3 IN HARD WATERFadli Ama, Suryani D. Astuti, Tri A. Prijo, Qod’nu Rahmawati, Yunus Susilo and Rahma A. Puspitasari
The formation of scale in the pipe walls and operating units due to high water hardness is a serious problem that is often found in industry. In general, scale deposits are composed of compounds which have low solubility, such as calcium carbonate (CaCO3). This study aims to determine the effect of the magnetic field and the duration of magnetic field exposure on CaCO3 precipitation in hard water and to determine the relationship between the magnetic field and the duration of exposure to CaCO3 precipitation. Sampling was carried out by mixing a solution of Na2CO3 and CaCl2 to form water hardness levels of 190-210 ppm. The sample is placed in a box that is capable of causing water to circulate. Samples were divided into Group T0, ie the control group without treatment, Group B1 was treatment with a magnetic field of 160 mT, group B2 was treatment with a magnetic field of 180 mT, and group B3 was treatment with a magnetic field of 200 mT with time exposure of the magnetic field is done for t1 is 30 minutes, t2 is 60 minutes, and t3 is 90 minutes. CaCO3 precipitation levels were measured using EDTA complexometric titration techniques. The data obtained were analyzed by factorial ANOVA statistics to determine the effect of treatment factors and the value of optimal treatment factors. The EDTA complexometry titration results showed a decrease in CaCO3 precipitation levels by 73.57 - 173.41 ppm or about 25.99% - 64.72% along with the induction of magnetic fields and the duration of exposure. The results of the factorial anova analysis showed that the most influential magnetic field at 200 mT and the most optimal exposure time at 90 minutes was able to reduce CaCO3 precipitation levels by 64.72%. Thus, the magnetic field and the duration of exposure affect the CaCO3 precipitation and there is a correlation between the magnetic field and the exposure time.