Dec. 16, 2015 Our drinking water is to a large extent purified by millions of "good bacteria" found in water pipes and purification plants, Swedish researchers have found. So far, the knowledge about ... read more
July 23, 2015 Both prescription and illegal drugs such as morphine, cocaine and oxycodone have been found in surface waters in Canadian rivers. New research shows that wastewater discharged from wastewater ... read more
Dec. 9, 2015 Inspired by the mangrove plant and human kidney, this novel biomimetic membrane is mechanically stronger and allows only water molecules to pass ... read more
Aug. 17, 2015 An oxidation process has been developed that uses ozone to degrade contaminants in water that alter the synthesis, transport, action or elimination of natural hormones, responsible for maintain ... read more
Mar. 24, 2015 Contaminants - such as medical residues and pesticides - go through the traditional wastewater purifying process and go back to the environment. Concern over their volyme in waste and drinking water ... read more
Arsenic Water Purification With Waste Materials
Mar. 16, 2016 Sand, coral and even waste building materials can become extremely efficient sorbents for water purification from arsenic, if they are treated for this purpose. Scientists have revealed a new ... read more
July 31, 2015 A synthetic membrane that self assembles and is easily produced may lead to better gas separation, water purification, drug delivery and DNA recognition, according to an international team of ... read more
July 19, 2017 Researchers have designed a tiny device -- built using a 3-D printer -- that can monitor drinking water quality in real time and help protect against waterborne ... read more
Mar. 20, 2017 What can the forests of Scandinavia possibly offer to migrants in faraway refugee camps? Clean water may be one thing, suggests a new ... read more
'Sweet' Solution Kills E. Coli in Drinking Water
Nov. 14, 2016 Paper strips laced with sugar could be the sweetest solution so far, literally, to kill E. coli in contaminated water. A researcher says the “DipTreat” discovery will be key to developing a new ... read more
Water Treatment Process Essay
Clean water supply is essential in establishing and maintaining a healthy community. There are two sources of water supply which are the surface water and ground water. Most natural waters are not suitable for consumption as it is contaminated by pathogens and also natural chemicals and minerals. In addition, as a city grew, wastes from human activities contaminate most of the water supplies. Water treatment plays an important role to properly treat a contaminated source of water supply in order to protect the health of consumers. Water treatment process is defined as a process of eliminating pollutants from untreated water to produce a biologically and chemically risk-free water, which is both potable and palatable for human consumption (SAJ Holdings Sdn Bhd., n.d.). There are six important steps in water treatment process, namely screening, aeration, coagulation and flocculation, sedimentation, filtration and lastly, disinfection (refer to Figure 1 in Appendix 1).
The first step in water treatment process is screening. Raw water undergoes physical screening to remove coarse material and debris as it comes to the water treatment plant. Screening separates particles according to their size alone. As mentioned by Hendricks (2006),
the objective of the screen is to accept a feed containing a mixture of particles of various sizes and separate it into two fractions, an underflow that is passed through the screen and an overflow that is rejected by the screen. (p. 121)
Screening is further divided into coarse and fine screens. Raw water undergoes coarse screen to eliminate floating material of fairly large size as preliminary treatment for the next step. These floating or submerged debris would damage pumps or block inlets, hence it is prudent to provide coarse screens (Binnie & Kimber, 2009). Fine screen removes waterweed, filamentous algae, small wastes, and the larger dwellers of raw water, which is typically the first stage of water treatment.
The second step of water treatment process is aeration. At the aerator, raw water is mixed with air. The aeration process helps to provide oxygen to the raw water which is needed for the oxidation process of dissolved iron and manganese in order for it to precipitate and therefore enables its removal through filtration (SAJ Holdings Sdn Bhd., n.d.). Wormleaton and Tsang (2000) stated that for water treatment process and also natural streams, it is essential to maintain a high amount of dissolved oxygen. Aeration also provides the escape of dissolved gases, such as carbon dioxide and hydrogen sulphide to reduce the corrosiveness of water, thus controls the tastes and odors of the water (Shun, 2007). Groundwater with high dissolved carbon dioxide levels or high concentrations of iron and manganese commonly require aeration as well as water drawn from reservoirs that is low in dissolved oxygen.
Thirdly, the proceeding water treatment step involves coagulation and flocculation. The objective of this step is to...
Loading: Checking Spelling0%