含有大量钙、镁离子的天然水称为硬水。硬水不能用于锅炉,因为硬水经煮沸而沉淀出来的钙盐和镁盐会沉积在锅炉内壁,形成水垢,这不仅影响供热,多耗燃料,而且会造成局部过热,损坏锅炉,甚至会引起爆炸事故。 硬水不但在许多工业生产上(如造纸、印染、医药等)不宜使用,它在日常生活中也不宜使用。如果用硬水洗涤衣物,肥皂就容易与硬水中所含的矿物质反应,生成不溶性化合物,不仅浪费肥皂,而且会 Natural water containing large amounts of calcium and magnesium ions is called hard water. Hard water can not be used in boilers because calcium and magnesium salts that have been precipitated by the boiling of hard water can deposit on the boiler walls and form scale that affects not only heating and fuel consumption but also local overheating and boiler damage that can even cause Explosion accident. Hard water not only in many industrial production (such as paper, printing and dyeing, medicine, etc.) should not be used, it is not suitable for use in daily life. If the clothes are washed with hard water, the soap easily reacts with the minerals contained in the hard water to generate insoluble compounds, which not only waste the soap but also