Sewerage Treatment Facilities - Report Example

Sеwеrаgе Тreatmеnt Fасilitiеs at Eastern and Western Treatment Plants By (Name) Institution Instructor Class/Course City Date Introduction The main reason treatment of wastewater or sewage is necessary is to allow industrial and human waste to be processed safely without harming the people or the environment. The effluent usually comprises of human waste, animal waste and industrial waste. A poor handling of this waste can pose serious health risks all forms of life including people, aquatic life and the environment. Major cities all over the world face a unique challenge of managing large volumes of waste from large populations and industries located within a small area. Melbourne is such a city and this report shall focus on its sewage treatment plants and processes (Hussain,et al. p 154-7). The sewage system in Melbourne is managed by Melbourne water which has a network of more than 400 Kilometers of sewers, two treatment plants and nine pumping stations. Each year Melbourne water treats over 320000 million liters of human and industrial waste. The nature of the sewage inputs at Werribee and Carrum and how it is transferred from Melbourne. The western treatment plant is located at Werribee west of Melbourne Australia. The plant serves a population of around 1.6 million people in the western, northern and northern suburbs and handles 60% of Melbourne’s sewerage waste. On the other hand, the eastern treatment plant located at Carrum east of Melbourne serves 1.5 million people of eastern and the south-eastern suburbs. It handles 40% of Melbourne’s sewerage waste (Hussain,et al. pp 153). The two treatment plants handle all the sewage from Melbourne. The treatment includes black water which is the waste water from toilets and greywater which is waste water from kitchen, bathroom and laundry. The waste from Warrribee and Carrum is treated used by some local customers as recycled water while the rest of the waste is released to Port Phillip Bay and South Eastern Outfall at Boags Rocks respectively. Traditional types of treatment originally used at Werribee The treatment approaches used at Warribee have evolved over time. However, at some point initially, the plant used the following traditional methods to treat waste: Grass filtration: This method was initially used in the 19 30’s and was the preferred treatment method during the winter when the soil wet and cloggy. During the treatment operation, the bulky trash is first removed from the waste by sedimentation process. The lighter trash then floats at the top surface of the vat while the heavier trash is drops to the lowest level of the vat. The treated sewerage is then left at the centre of the vat (Jones, et. al pp.203-6). The treated sewerage was then flooded through channels that had grass that could filter the sewage. The filtered solids could then be cleaned out. The pollutants in the water were removed by the bacteria found in soil. At the end of the channel, the treated sewage flowed to a drain that released it to Port Phillip Bay. Land filtration: This method was preferred during summer when the weather conditions are hot and the land is dry to absorb wastewater quickly. It was used first in 1897. In this treatment approach, an exposed land is filled with sewage to a height of about 10 cm. While the solids are filtered to remain on the surface, the sewage soaks into the ground and streams out into the drain the released to Port Phillip Bay. The pollutants from the sewage are broken down by the bacteria in the soil while the nutrients are used by the grass to grow. The land filtration process takes around three weeks and is carried out in phases (Jones, et. al pp.203-6). The land is flooded for two days and it takes around five days for the soil to absorb the sewage. After the paddock has dried, sheep and cattle can graze the grass for two weeks then the process begins again. Lagoon treatment: This treatment process was used first in 1936. They are suitable for the climate of high solar irradiation and growing season throughout the year. Tropical areas form an ideal climate for lagoons. In this process, raw sewage is poured to an excavated large open basin on earth. The naturally degraded waste by bacteria, algae and another pathogenic organism is removed by aeration and sunlight exposure. The natural lagoons used initially and were low cost and used little or no chemical for the process. These lagoons have since been the lagoons have since been replaced by modern lagoons with the first modern lagoon being constructed in 1986. The old traditional treatment approaches had their shortcomings and new methods are currently being applied at Werribee and Carrum in sewage treatment. Method of treatment currently used at Werribee, the recent improvements and why were they introduced Currently, the Werribee plant uses modern lagoons that are made up of 10 pools. Each of the pools has the capacity ton hold around 600 million litres of wastewater. The sewage is run on the ponds as the bacteria in the pond's breaks down the organic solids (Jones, et. al pp.206). The waste is made clearer as it goes through each pool. The sewage undergoes the following treatment process at Werribee: · The raw sewage from Melbourne enters the lagoon at Weribee · The shelters remove the smell and cut out the greenhouse emissions from the waste as methane is collected · The collected methane gas is recycled, generating electrical energy that powers aerators and other parts of the centre · The aerator dissolve oxygen into the wastewater · An activated sludge process re4moves nitrogen from the sewage · After around 30 to 35 days, the treated sewage in the lagoon can be recycled or released to Port Phillip Bay. · The water used by the plant is recycled and delivered to various offsite clients who include the Hoppers Crossing pumping station in Melbourne and is also used for irrigation and on-site upkeep. There have been improvements to create the modern lagoon treatment plant at Werribee that has two ponds: the anaerobic pond which does not use oxygen and the aerobic pond which uses oxygen. The two processes create two different bacteria that break down the sewage waste. The anaerobic process has bacteria that consume the oxygen that breaks down the waste in the sewage. The bacteria in an anaerobic process release strong pungent odors and greenhouse emissions that are hazardous. The improved ponds have shelters that capture and remove the pungent smell and greenhouse emissions that were prevalent in the old lagoons. The gases that are removed from biogas that produces electrical energy runs the facility (Jones, et. al pp.200-9). The oxygen that accumulates as the waste is treated is forced into the water by the aerators in the initial phase. The oxygen decreases the unpleasant smell as it goes through the rest of the ponds. The treatment currently used at Carrum The waste treatment at Carrum uses a secondary standard which involves two phases of primary and secondary treatment. Primary treatment: This process consists the cleaning out of bulky items from the waste using fine filters. The fine particles in the water are ventilated while the bulky particles drop at the bottom forming sludge. The bulky particles and sludge are sent to digesters with bacteria the breaks them down later. Secondary treatment: The secondary treatment involves the breaking down and removal of organic substances from the aeration vats by the same bacteria found in the Lagoon treatment. The wastewater will then go to the sedimentation vats and the sludge again drops at the bottom of the vats. The sludge creates a cleaner and cleaner effluent. The effluent is then held in ponds before it is finally screened. After screening, the treated wastewater is then recycled or disinfected by chlorine and released to the environment. Currently, plans are underway to upgrade Tertiary treatment in the near future. Problems in the treatment of sewage from a major city like Melbourne The main problem that cities face is the colossal amount of effluents that is released by the cities. In a year, Melbourne Water Company treats 320,000 million litres of sewage that includes trade waste. The water from these treatment plants, though treated, mostly ends up in the country’s waterways causing serious health hazards. To overcome this problem, cities need to take advantage of new technology to improve their waste management practices. To start with, they can recycle the waste has been proven to provide excellent results. For example, the waste can be recycled to fertilizer and other beneficial components. Also, the chemical energy can be converted to electricity used in the plants and other facilities. Lastly, the plants can use technology like robots to monitor the sewage lines for any leaks or malfunctions. Why Warribee is perfect place for sewage facility The area of Warribee treatment plant is perfect because it provides lakes, creeks, lagoons, and salt marsh which are good waterways to carry the treated wastewater. In addition to that, Werribee provides beautiful landscape scenery and is also a tourist attraction for bird watching. Environmental impacts of the Werribee facility There is an obviously adverse effect on the environment because of the presence of the facility at Weribee. To start with, when the plant used the old traditional treatment processes as grass and land filtration, much nitrogen from the waste water was entering into the Port Phillip Bay. Water is polluted putting the health of the Melbourne people at risk and even the creatures that live in water. The unpleasant smell emitted from the processing plant was unbearable and made the area inhabitable. The greenhouse emissions from the plant have also caused for concern for the Melbourne population. However, with the development of the facility and adoption of modern methods of sewage treatment, the above adverse effects have significantly been reduced. The greenhouse emissions have been minimized as the gases are now being used to generate electricity. The process has improved efficiency at the facility and reduced costs of electric power usage. The methane gas captured while the treatment process has also reduced the unpleasant smell from the plant hence making the atmosphere bearable and habitable. Problems with location of the site at Carrum The aquatic life in Carrum has been affected negatively by the release of sewage to the waters. The levels of ammonia in the treated wastewater are a major concern because it seems to affect the aquatic life and the people around Carrum. However, there are concerted efforts to decrease these levels of ammonia by applying modernized methods of treatment of sewage. Conclusion There are no doubts, the Warribee and Carrum treatment facilities under the management of Melbourne Water, has a critical role in managing waste in Melbourne. The two plants have also provided a good educational and research resource for continuous study and development of waste management and sewage treatment all over the world. That notwithstanding, the methods of treatment used at the plants have to keep improving with time to mitigate the obvious environmental impact of the methods. With creating and adoption of new technology especially in the area of recycling, the outcome of the whole process of sewage treatment can be optimized. References Hussain, M. A., Ford, R., & Hill, J. 2010. Determination of fecal contamination indicator sterols in an australian water supply system. Environmental Monitoring and Assessment, 165(1-4), 147-57. doi:http://dx.doi.org/10.1007/s10661-009-0934-5 Jones, B.E., H., Haynes, R.J. & Phillips, I.R. 2011, "Influence of organic waste and residue mud additions on chemical, physical and microbial properties of bauxite residue sand", Environmental science and pollution research international, vol. 18, no. 2, pp. 199-211. http://www.melbournewater.com.au/whatwedo/treatsewage/wtp/Pages/western-treatment-plant.aspx Li, P.J., Stagnitti, F., Xiong, X. & Peterson, J. 2009, "Temporal and spatial distribution patterns of heavy metals in soil at a long-standing sewage farm", Environmental monitoring and assessment, vol. 149, no. 1-4, pp. 275-82. http://www.melbournewater.com.au/whatwedo/treatsewage/etp/Pages/eastern-treatment-plant.aspx www.melbournewater.com.au Read More

Land filtration: This method was preferred during summer when the weather conditions are hot and the land is dry to absorb wastewater quickly. It was used first in 1897. In this treatment approach, an exposed land is filled with sewage to a height of about 10 cm. While the solids are filtered to remain on the surface, the sewage soaks into the ground and streams out into the drain the released to Port Phillip Bay. The pollutants from the sewage are broken down by the bacteria in the soil while the nutrients are used by the grass to grow.

The land filtration process takes around three weeks and is carried out in phases (Jones, et. al pp.203-6). The land is flooded for two days and it takes around five days for the soil to absorb the sewage. After the paddock has dried, sheep and cattle can graze the grass for two weeks then the process begins again. Lagoon treatment: This treatment process was used first in 1936. They are suitable for the climate of high solar irradiation and growing season throughout the year. Tropical areas form an ideal climate for lagoons.

In this process, raw sewage is poured to an excavated large open basin on earth. The naturally degraded waste by bacteria, algae and another pathogenic organism is removed by aeration and sunlight exposure. The natural lagoons used initially and were low cost and used little or no chemical for the process. These lagoons have since been the lagoons have since been replaced by modern lagoons with the first modern lagoon being constructed in 1986. The old traditional treatment approaches had their shortcomings and new methods are currently being applied at Werribee and Carrum in sewage treatment.

Method of treatment currently used at Werribee, the recent improvements and why were they introduced Currently, the Werribee plant uses modern lagoons that are made up of 10 pools. Each of the pools has the capacity ton hold around 600 million litres of wastewater. The sewage is run on the ponds as the bacteria in the pond's breaks down the organic solids (Jones, et. al pp.206). The waste is made clearer as it goes through each pool. The sewage undergoes the following treatment process at Werribee: · The raw sewage from Melbourne enters the lagoon at Weribee · The shelters remove the smell and cut out the greenhouse emissions from the waste as methane is collected · The collected methane gas is recycled, generating electrical energy that powers aerators and other parts of the centre · The aerator dissolve oxygen into the wastewater · An activated sludge process re4moves nitrogen from the sewage · After around 30 to 35 days, the treated sewage in the lagoon can be recycled or released to Port Phillip Bay.

· The water used by the plant is recycled and delivered to various offsite clients who include the Hoppers Crossing pumping station in Melbourne and is also used for irrigation and on-site upkeep. There have been improvements to create the modern lagoon treatment plant at Werribee that has two ponds: the anaerobic pond which does not use oxygen and the aerobic pond which uses oxygen. The two processes create two different bacteria that break down the sewage waste. The anaerobic process has bacteria that consume the oxygen that breaks down the waste in the sewage.

The bacteria in an anaerobic process release strong pungent odors and greenhouse emissions that are hazardous. The improved ponds have shelters that capture and remove the pungent smell and greenhouse emissions that were prevalent in the old lagoons. The gases that are removed from biogas that produces electrical energy runs the facility (Jones, et. al pp.200-9). The oxygen that accumulates as the waste is treated is forced into the water by the aerators in the initial phase. The oxygen decreases the unpleasant smell as it goes through the rest of the ponds.

The treatment currently used at Carrum The waste treatment at Carrum uses a secondary standard which involves two phases of primary and secondary treatment.

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