15 Notifications You have no notifications See all Course Overview SECTIONS Welcome to Textile Chemistry 1 Teacher's Information 2 Course objectives, outlines, assessment plan, reference books, google calendar 3 Lecture 1 to 6 about water pollution and control 4 Lecture 7 to 12 about Dyes and Pigments 5 Lecture 13 to 17 about Oil, fat and Waxes 6 Lecture 18 to 21 about Fabric Finishing Chemicals 7 Lecture 22 to 30 about Soap and Detergent 8 Exam Spring-2021 9 Assignment Spring-2021 10 Skip to main content Textile Chemistry (Spring-21) Dashboard My courses TE-215 (DFR-211) Lecture 1 to 6 about water pollution and control Question/Answer session about water purification Search Question/Answer session about water purification How to use hard water in textile industry Display mode Display replies in nested form Picture of ashrafi antora How to use hard water in textile industry by ashrafi antora - Sunday, 7 February 2021, 8:46 PM Number of replies: 0 If we want to use hard water in textile dye processing first off all we need to remove the hardness of water. There are two types of hardness. (a) Temporary hardness, (b) permanent hardness. (a) To remove temporary hardness we need to boil the hard water. (b) To remove permanent hardness we need to do reaction the water with Sodium carbonate and Calcium Hydroxide. Temporary hardness: 1. Ca(HCO3)2 + Ca(OH)2 → 2CaCO3 ↓ +2H2O 2. Mg(HCO3)2 + 2Ca(OH)2 → 2MgCO3 +2H2O 3. MgCO3 + Ca(OH)2 → Mg(OH)2 + CaCO3 Permanent Hardness: CaSO4 + Na2CO3 → CaCO3+ Na2SO4 MgSO4 + Na2CO3 → MgCO3+ Na2SO4 MgCO3 + Ca(OH)2 → Mg(OH)2 + CaCO3