Studi Perbandingan Keefektifan Penggunaan Poly Aluminium Chloride (Pac) dan Tawas (Alum) terhadap Turbiditas dan Kadar Logam Aluminium pada Air Baku Instalasi Pengolahan Air di Pdam Tirtanadi Hamparan Perak

Abstract

The comparative effectiveness study of the usage of the poly aluminium chloride (PAC) and alum towards the turbidity and the aluminium levels at the water treatment installation of PDAM Hamparan Perak has been carried out. The concentration of aluminium chloride and alum usage compared in the raw water has initial turbidity 73,3 NTU and aluminium levels of 0,048 mg/l is respectively 19 ppm; 21 ppm and 23 ppm. And being stirred with agiator found in the Jar Test with a 140 rpm rotation speed for 5 minutes reduced to 50 rpm for 10 minutes, then the agiator is stopped to have the flocks sedimented after being soothed for 20 minutes. The turbidity is measured by the turbidimeter while the aluminium levels is by the spectrophotometry. From the research, it is found that the levels of the poly aluminium chloride in the raw water is 19 ppm; 21 ppm and 23 ppm and the turbidity is 0,88 NTU; 0,68 NTU and 0,74 NTU, and the aluminium levels is 0,059 mg/l; 0,060 mg/l and 0,073 mg/l. For the use of alum concentration in the raw water is 19 ppm; 21 ppm and 23 ppm, for the turbidity is 6,71 NTU; 6,52 NTU and 4,47 NTU and for aluminium levels is 0,630 mg/l; 0,390 mg/l and 0,306 mg/l. Comparing between the turbidity and the aluminium levels from the obtained result of the turbidity and the metal level adequate to the standard of the drinking water quality, it is found that the use of poly aluminium chloride coagulant is more effective compared to the use of alum.