Types of Water Hardness
TEMPORARY HARDNESS This refers to hardness whose effects can be removed by boiling the water in an open container. Such waters have usually percolated though limestone formations and contain bicarbonate…
Water Softening
Water is a universal solvent. Soft rainwater picks up naturally occurring dissolved minerals, including calcium and magnesium carbonates, as it passes over rocks and through soil, which begins to make…
How does disinfection work?
Chemical inactivation of microbiological contamination in natural or untreated water is usually one of the final steps to reduce pathogenic microorganisms in drinking water. Combinations of water purification steps (oxidation, coagulation, settling, disinfection, filtration)…
What is water disinfection?
Water disinfection means the removal, deactivation or killing of pathogenic microorganisms. Microorganisms are destroyed or deactivated, resulting in termination of growth and reproduction. When microorganisms are not removed from drinking water,…
Filtration Processes
Introduction Filtration is a process that removes particles from suspension in water. Removal takes place by a number of mechanisms that include straining, flocculation, sedimentation and surface capture. Filters can…
Sedimentation
When water has little or no movement, suspended solids sink to the bottom under the force of gravity and form a sediment. You will recall that we discussed a similar…
METHODS OF AERATION
Two general methods may be used for the aeration of water. The most common in industrial use is the water-fall aerator. Through the use of spray nozzles, the water is…
Aeration
Aeration is a unit process in which air and water are brought into intimate contact. Turbulence increases the aeration of flowing streams (Figure 4-1). In industrial processes, water flow is…
Household Water Treatment
Even though EPA regulates and sets standards for public drinking water, many Americans use a home water treatment unit to: · Remove specific contaminants · Take extra precautions because a household member…
Wastewater Screening
Wastewater Screening is the first unit operation in all wastewater treatment plants. Screen is the device used to retain solids found in the influent wastewater to the treatment plant. The main…
