Water and Wastewater Engineering - Research Paper Example

TABLE OF CONTENTS CONTENTS PAGE Introduction 2. Wastewater 3. Water Supply and Wastewater Management2 3.1 Water Supply Planning 2 3.2 Wastewater Treatment 3 3.3 Systems for Water Purification and Wastewater Treatment 4 3.3.1External Treatment 4 3.3.2 Mechanical Filtration 4 3.3.3 Reverse Osmosis 5 3.3.4 Chemical Treatment 5 3.4 Treatment Plant Design 6 3.5 Water Distribution System 7 3.6 Wastewater Collection System 8 4. Conclusion 8 References i Appendix A (Water Treatment Process) ii Appendix B (Water Treatment and Distribution) iii Appendix C (Wastewater Collection Process) iv Water and Wastewater Engineering 1. Introduction Water is one of the few natural resources present in the world. Without this natural resource, no species on the earth can survive. Tancev (2005, p.3) asserts, “Water plays an exceptionally significant role in the economic development of all countries”. But as water is essential for the economic and industrial development of a country, it is equally harmful in the form of wastewater. Many municipalities have implemented effective wastewater treatment plants that not only purify the sewage but also recycle the water for many purposes. The treatment plants make use of various methods in order to recycle and purify the wastewater. Some common treatment methods include filters and chemical treatments. Governments of all countries should give proper attention to the wastewater management and purification system’s implementation in order to make an effective use of wastewater. 2. Wastewater Waster water is the water that has been brought into use in home or in industries and is no longer fit for human consumption. Some examples of wastewater include discharged water from offices, households, buildings, hotels, factories, and industries. Discharged water contains such substances, which are very harmful for the health of human beings. Tatum (n.d.) asserts, “Wastewater can also refer to groundwater that is contaminated due to leaking septic tank or agents such as insecticide, petroleum products, blood, or cleaning liquids”. Contaminated water is neither good for health of humans nor for the soil as it contains harmful and detrimental chemicals. As wastewater is harmful for health, it should be purified using water treatment and purification methods in order to make it clean and decontaminated. Wastewater should be run through filtration systems in order to make it usable once again. 3. Water Supply and Wastewater Management Water supply is the process of supplying clean water to the public and industries for various purposes. Water supply management manages the resources to ensure the supply of clean and purified water to the people. There are two aspects of water supply management, which include supply management and demand management. Supply management indicates control by the supply authority and implies autocratic or un-transparent planning whereas demand management indicates management of the demand of water by stakeholders, consumers, and the community (Stephenson, 1998). Some factors are of significant value for the effective management of water supply. These factors include ensuring provision of basic water requirements, transfer of river water from wet to dry regions, reducing the shortfall risks, reducing the water pollution risks, carryover from flood to drought, minimizing the costs, future planning, and creating the awareness regarding value of water. Water supply management not only involves utilization of purified water but also involves such mechanisms, which are helpful in using the equipment in a proper manner in order to produce quality water at a better price, thus minimizing the water purification and supply costs. 3.1 Water Supply Planning Planning of water supply is necessary in order to ensure that purified drinking water is available for household and industrial purposes. The planning includes an assessment of water supplying companies’ ability to meet the demands in an effective manner. As water is a necessity, governments of all countries take proper measures in order to store the river water for using it in future. Risk management is an important part of water supply planning. Stephenson (2005, p.301) asserts, “It is often not recognized how important risk management is in planning and operation of water services”. Other key factors influencing water supply planning include analysis of water storage dams, analysis of existing water supply systems, removing flaws in the existing systems, making water supply reach all cities and towns, development of water treatment plants in order to decontaminate the wastewater, and meeting the water demands in an appropriate manner. 3.2 Wastewater Treatment Runion (2010) asserts, “The treatment process involves elaborate steps of reducing turbidity first to allow the suspended particulates to settle and the natural organisms to then disintegrate the effluents”. Wastewater treatment is one of the most important requirements of water supplying companies. No company is supposed to supply unpurified water to the public. Wastewater requires to be decontaminated because it includes harmful substances such as human waste, oils, small particles of materials, soaps, and chemicals. Wastewater also comes from homes and includes dirty water from bath sinks, tubs, and toilets. Wastewater should be decontaminated because contaminated water is not only harmful for health but also for the environment. Those pollutants, which are very harmful for water life and humans, include decaying organic matter and debris, excessive nutrients, mercury, cadmium, lead, inorganic chloramines, and chlorine compounds. Wastewater treatment discharges the solid materials back to the environment. The primary treatment removes approximately 70 % of the suspended solid materials. The secondary treatment removes the remaining materials from the water and makes it perfect for use. Aerating, a process involved in the treatment, puts the oxygen back in the water. 3.3 Systems for Water Purification and Wastewater Treatment Some of the main methods used for water purification include external treatment, mechanical filtration, reverse osmosis, and chemical treatment. Let us describe all of them in some detail. 3.3.1 External Treatment In external treatment, water purification is done either separately or by using a combination of more specific water treatment techniques. Some of those techniques include cal carbonate hot, cold cal carbonate, and hot calcium chloride. This method of water purification is used in such water treatment plants that have the capacity to contain a high volume of water. 3.3.2 Mechanical Filtration Mechanical filtration method is also known as micro filtration. The suspended materials that are removed from the water using this method include organic matters, sand, and silk. This method is primarily intended to remove particulate matter by passing water over a medium such as floss, foam, or diatomaceous earth. By using mechanical method in combination with some other filtration methods, almost all forms of turbidity get removed. The filters used in this filtration method include fabrics and fibers. 3.3.3 Reverse Osmosis Reverse osmosis method removes various organic and inorganic chemicals from the wastewater. They are more effective in removing inorganic compounds than organic compounds. Reverse osmosis is often used in combination with activated carbon filters and mechanical filters in order to effectively remove all suspended substances. Some of the major substances that are removed using reverse osmosis filtration include lead, calcium, sodium, aluminum, organic chemicals, and microorganisms. The basic components of the reverse osmosis system include cold water line value, pre-filters, post-filters, RO membrane, automatic shut-off valve, check valve, flow restrictor, faucet, storage tank, and the drain line. The stages involved in working of these three filtration methods include removal of dirt and impurities through mechanical filters, installation of reverse osmosis unit, putting the water in a pressurized water storage container, addition of an activated carbon filter, and removal of organic compounds by passing them through reverse osmosis filter. There are some factors that affect the overall performance of reverse osmosis system and play a crucial role in improving the working of RO filtration system. These factors include incoming pressure of the water, temperature of the water, type of dissolved solids, quantity of dissolved solids, quality of the filters, and quality of the membrane used in the reverse osmosis system. 3.3.4 Chemical Treatment Chemical treatment of water is one of the widely used methods of water purification. This treatment kills all bacteria present in the water. Not only bacteria, but also some viruses such as amoeba and giardia are killed due to chemical treatment. Cheremisinoff (1995, p.589) asserts, “Chemical precipitation has often been used to remove metals and other inorganic materials from wastewater”. Some other purification techniques are used along with chemical treatment depending upon the level of water contamination. Those techniques include addition of chemical to prevent formation of reaction products, use of clarification process to remove the suspended substances, deionization and softening, disinfection, distillation, electro dialysis, and scavenging. This treatment involves use of chlorine and iodine for making the impure water free of bacteria and viruses. The effectiveness of chemical treatment depends on some important factors that include water’s temperature, time of contact, and concentration of the chemical. It is important to keep the concentration level and the temperature level high in order to kill all bacteria present in the water. Along with chlorine and iodine, halazone tablets are also used to purify the water. 3.4 Treatment Plant Design Design of the treatment plant is extremely important for the effective working of the plant. Engineers make use of two design flows in order to select an appropriate treatment plant design. These design flows include design process flows and design hydraulic flows. Vesilind (2003) found that design process flow is used to design the processes such as clarification and activated sludge whereas the design hydraulic flow is used to design the hydraulic structures related to the treatment plant. The use of hydraulic flow is of more importance as compared to the use of design process flow. The engineering professionals always make sure that the plant should be able to pass the water during the times when the flow of water is considerably high. The plant should not get flooded out with water and it should have the capacity to pass maximum flow of water. There are some factors, which are taken into consideration by the engineers in order to maintain an appropriate ratio between design process flow and design hydraulic flow. Those factors include size of the community, wastewater stream sources, type of wastewater collection system, and condition of wastewater collection system. The layout of the wastewater treatment plant depends on some key factors such as availability of treatment facilities, provisions for future expansion, tank geometry, treatment redundancy, hydraulics, operational flexibility, continual treatment during construction, maintenance, and infrastructural facilities. “The arrangement of treatment processes on a plant site affects operating and construction costs” (Vesilin, 2003). The engineers design a rough hydraulic profile before locating the facilities on a new site. Provision of future expansion is also an important aspect of a new treatment plant design because treatment plants need to be upgraded or refurbished after a specific period. The engineers also keep future hydraulic expansions in mind while designing the hydraulic structures for the plant. Along with treatment facilities and design of the hydraulic structures, all other key factors including tank geometry, operational flexibility, and infrastructural facilities play a crucially important role in the successful working of a new wastewater treatment plant. 3.5 Water Distribution System Water distribution system acts as a link between water supplying companies and the consumers. It a network of hundreds of pipelines that make the water reach the industries and consumers’ homes. Pumping machines are used to make the water continuously run through the network. Water distribution system performs a number of important tasks including maintenance of main pile lines and providing water services to the consumers. 3.6 Wastewater Collection System Wastewater collection system is a system that collects contaminated water from homes and industries. Drainage facilities and sewerage systems are two important parts of wastewater collection system. Anderson (2010), in an article, expresses his views regarding sewerage systems and asserts, “They can have a severe impact on environmental and sanitary issues if capacity and maintenance are inadequate”. Wastewater collection systems are just as important as water distribution systems because inappropriately planned wastewater collection systems result in flooding the streets and basements with contaminated water. 4. Conclusion Summing it up, we can say that water is one of the necessities of life without which no species can survive. However, it is equally harmful for the human beings and other species if it becomes contaminated. Contaminated water includes harmful substances such as human waste, oils, small particles of materials, soaps, and various industrial chemicals. Contaminated water is not only harmful for the health but also for the environment. Many wastewater treatment methods are there which effectively purify the contaminated water. Effective Wastewater collection, distribution, and purification mechanisms are very important not only for environmental cleanliness but also for the satisfaction of the public living in any specific country. Therefore, the water distribution divisions should take proper measures to provide clean and hygienic water to the consumers. References Anderson, H 2010. Wastewater Collection Systems, viewed 22 July 2010, Cheremisinoff, P., 1995. Handbook of water and Wastewater Treatment Technology. New York: Marcel Dekker, Inc. Runion, R 2010. Wastewater Turbidity – How to Quantify Suspended Solids, viewed 22 July 2010, Stephenson, D., 2005. Water Services Management. Cornwall: IWA Publishing. Stephenson, D., 1998. Water Supply Management. Netherlands: Kluwer Academic Publishers. Tancev, L., 2005. Dams and Appurtenant Hydraulic Structures. London: Taylor & Francis. Tatum, M n.d., What is Wastewater?, viewed 22 July 2010, Vesilind, P., 2003. Wastewater Treatment Plant Design. Cornwall: IWA Publishing. APPENDIX A (Water Treatment Process) APPENDIX B (Water Treatment and Distribution) APPENDIX C (Wastewater Collection Process) Read More