MICROANALYSIS PEMBENTUKAN KRISTAL CALSIUM SULFAT PADA PIPA BERALIRAN LAMINER DENGAN PARAMETER LAJU ALIR

Abstract

Abstract

Gypsum (CaSO_4. 2H₂O) scaling inside pipe is very problematic for industries since it causes narrowing of pipe diameter, thickening of heat transfer surfaces, lenghthening the process time and finally increase the cost of production. It is therefore necessary to prevent the occurance of gypsum scaling in a piping system. This report describes an experiment on gypsum scale formation utilizing CaCl₂.2H₂O and Na₂SO₄ solutions to form gypsum ( CaSO₄. 2H₂O). The concentration the calcium ions selected was 3,500 ppm. The experiment was carried out a pipe with several coupons made of copper representing common pipe material used in industry. Flowrate of gypsum solution as one of process parameters for gypsum scaling was varied: 30, 40 and  50 ml/minute  respectively. In addition, Cu²⁺ as impurities was aded into the solution : 5 and 10 ppm respectively. In adition, a microanalysis on the scale was also caried out using EDAX. The mass of the scale formed was calculated in order to determine the rate of the gypsum scale growth.

Keywords : flowrate, gypsum, impurities, piping system.