The treatment of surface wastewater is aimed at bringing contaminated water back to its previous state for domestic use or otherwise. Some of the sources of wastewater include industrial effluents from manufactures, agricultural effluents, agro-industrial as well as domestic wastewater from sinks, bathtubs, toilets, and so on. Particles in the water from the various sources include bacteria, organic matters, and sand which cause the water to be turbid or discoloured in appearance and have an unpleasant odour.
As a result, the removal of the dissolved or suspended components from all these sources is critical in wastewater treatment. This vital process includes coagulation and flocculation (both processes work in tandem). In these processes, small or minute suspended particles that are present in the effluent (called colloids) and together with humic acids (produced from the decay of organic materials) form larger clumps called flocs. This allows for the settling and hence easy removal of the particles from the water; thereby achieving the removal of the turbidity from the treated water. In addition to the removal of turbidity, coagulation and flocculation also removes numerous microorganisms suspended in the water as well as phosphates from the water. For safety, the highest level of turbidity that is allowable in water is 0.5 NTU, and the recommended level is 0.1 NTU. (NTU: Nephelometric Turbidity Units)
Colloidal particles:
These small particles are primarily negatively charged when suspended in water. As a result, there is strong repulsion among each other, causing them to be separated from each other and are not available for removal. They may be hydrophilic or hydrophobic, depending on how they are stabilized. Hydrophilli...
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Two solutions were prepared by using Calcium Nitrate Ca(〖NO_3)〗_2 with concentration of 0.101 M, Potassium Iodate KIO_3 with concentration of 0.100 M, and deionized water. First solution contained 25.0 mL of Calcium Nitrate and 25.0 mL of Potassium Iodate. In the second solution, 15.0 mL of deionized water were added with 10.0 mL Calcium Nitrate and 25.0 mL of Potassium Iodate. Each of these solutions was mixed for 15 minutes. After the reaction of the solutions took place, each of the solutions was filtered. To remove water liquid from the filtered solution, both of the precipitates in the
Comment on class result with respect to differences in filter types, differences in filter assemblies, and overall on the confidence you would have in using this type of sterilisation process in preparation of pharmaceutical products. List the factors that may cause contamination during filtration. (20 marks)
When in solution, the hydronium and chloride ions formed will be partially surrounded by water molecules via ion-dipole bonds, an electrostatic force of attraction that exists between charges in the ions and the partial charges in the water molecules. Water molecules surrounding ions is called hydration.
...eading contributor of pollutants to lakes, rivers, and reservoirs…..Surface discharges can be caused by heavy storms or floods that cause storage lagoons to overfill, running off into nearby bodies of water. Pollutants can also travel over land or through surface drainage systems to nearby bodies of water, be discharged through manmade ditches or flushing systems found in CAFOs, or come into contact with surface water that passes directly through the farming area.
Stephenson, R., & Blackburn, J. J. (1998). The Industrial Wastewater Systems Handbook. New York: Lewis Publishers.
The key stakeholders are Peter Vyas, the manager of filtration unit and Cynthia Jackson who is the vice president of water management division. Vyas was convinced that the survival of the unit depended upon innovative growth and thus he appointed a technology evaluation team with the responsibility of using technology to solve the problem of obtaining clean water in remote regions, by developing a small-scale oxidation system that enabled waste-water disinfection in small batches. His utmost concern is the technological aspect of developing the product. On the other hand, Cynthia’s perspective was shaped by the marketing angle of the product. She recommended the development of future proposals using a rigorous three phase process which links the markets analysis and technological development to busines...
Chemically enhanced primary treatment (CEPT) is a wastewater treatment method that provides as smart alternative to the conventional primary treatment. It can also be used as a proficient preliminary step of the biological secondary treatment processes. CEPT embraces coagulation and flocculation, and it accomplishes remarkable increases in the pollutants removal from the influent (Ødegaard, 1989; Rashed et al., 1997; Ayoub et al., 2013; Rashed et al., 2013a; Rashed et al., 2013b). Chemical precipitation is the technique of CEPT process, the main idea of chemical precipitation that it converts soluble substances to insoluble particles, which can be flocculated and separated from the liquid. Removal efficiencies depend on mixing times, mixing
Sediment transport model plays an important part in the aquatic system as aquatic systems display slow recovery rates due to the continued presence of toxic substances. In a water column, toxic substances accumulate in the bottom sediments of aquatic systems. Depending on the chemical properties and hydraulic characteristics, sorption to biotic and abiotic suspended matter may occur, resulting in chemical settling from the water column and accumulating among bottom sediment. In addition, the effects of industrial contamination on aquatic life are a continuing concern of local, state, and federal agencies throughout the United States.
There are several types of treatment methods present but biological treatment methods have gained much traction in the recent years due to their low operation costs, comparatively benign effects on the environment and their ease of handling and maintenance. Biological wastewater treatment methods can be subcategorized into dispersed growth systems and attached growth systems. Biofilms fall under the latter category (Sehar & Naz, 2016)
The bacteria and wastewater is mixed in an aeration tank and therefore the contaminants are removed by action of sorption and series of breakdown by the bacteria.
1999, 71, 181-215. Minear, R., Amy, G.. Water Disinfection and Natural Organic Matter: History and Overview. ACS Symposium Series -. 1996, 649, 1-9. Richardson, S. Water Analysis: Emerging Containments and Current Issues. Journal of Analytical Chemistry. 2003, 75, 2831-2857.
around the end of the 19th century, when piped water supplies and the use of flush toilets lead to an increased water consumption, and waste-water production. This led to streams and stagnant pools of wastewater in city streets, causing outbreaks of cholera and other diseases. To tackle this problem, sewer systems were gradually introduced. Later, when this was seen to cause serious water pollution, step by step mechanical wastewater treatment plants, biological treatment for the degradation of organic substances, and tertiary treatment for the removal of nutrients were added to reduce the pollution and resulting eutrophication of the receiving water bodies. These now represent the present state-of-the-art in wastewater treatment. The problems become particularly serious when there is a rapid increase in the urban population.
The terms secondary and primary treatment have been used to basically describe a degree of treatment; for example, biological wastewater treatment and settling. Tertiary treatment has been regarded as different from secondary and is the advanced one. It comprises of the use of sand filters to separate the solid particles from the wastewater. Tertiary treatment has also been regarded as the treatment involved to remove plant nutrients, primarily nitrogen and phosphorous.
Domestic households and industrial and agricultural practices often produce wastewater that can cause rivers and lakes to become polluted. This is typically called sewage and wastewater pollution. Sewage is a term for wastewater that usually contains feces, urine, and laundry waste. With there being billions of people on earth, treating sewage is a big priority. Untreated sewage can contam...
Water plays such an important role in our daily lives. 70% of our body is composed of water. 70% of the earth surface is also made up of water, but out of the 70%, only 1/3 of water is consumable. In fact, this amount has been continuously to decrease as more and more industries began to pollute and damage the water. For example, many toxic chemicals may be released into the water thus making the water impure. Such pollutions and damages lead the water to be contaminated and inconsumable as it may cause severe diseases. Water purification can remove all the unnecessary bacteria and viruses from the water that is hazardous for our health. Water purification may also improve the flavor and appearance of water. It removes the unpleasant odor. Therefore, water purification became one of the most useful and popular process used by people all over the world today. It is by far the most recommended and safest water treatment that is commonly used to purify damaged water into consumable water. Water purification provides us with safe, pure and clean water to consume and use.