The alum is dissolved in water and the aluminum ions, Al 3+ that form, have a high capacity to neutralize the negative charges which are carried by the colloidal particles and which contribute to their stability.
Published in Chapter:
Water Purification Using Different Chemical Treatment
Rupali Rastogi (ITM University, India)
Copyright: © 2019
|Pages: 30
DOI: 10.4018/978-1-5225-6111-8.ch019
Abstract
Water from surface sources is often contaminated by microbes, whereas groundwater is normally safer, but even groundwater can be contaminated by harmful chemicals from human activities or from the natural environment. The purification process of water may reduce the concentration of particulate matter including suspended particles, parasites, bacteria, algae, viruses, fungi, and a range of dissolved and particulate material derived from the surfaces. Water purification is the process of removing undesirable chemicals, materials, and biological contaminants from contaminated water. Most water is purified for human consumption (drinking water), but water purification may also be designed for a variety of other purposes, such as medical, pharmacology, chemical, and industrial applications. In general, the methods used include physical processes such as filtration and sedimentation, biological processes such as slow sand filters or activated sludge, chemical processes such as flocculation and chlorination, and the use of electromagnetic radiation such as ultraviolet light.