Wastewater Treatment Feedback

wastewater Treatment 2feedback From

You need to include the whole thing from the Unit I. Also you need to pay attention to how to write pH. Wastewater treatment The two most used processes of water purification are the chemical and the biological processes. However, most of the purification methods that lie under the chemical and the biological means purify water only to about 95%. There is therefore a need to come up with a way to make the water totally clean and safe for use.

This is where comes in flocculation, sedimentation and coagulation. Coagulation is the process of compacting diffused impurities to form solid or semi solid lumps that can be filtered out of a solvent. The process mostly leads to a suspension being formed. Sedimentation process is the process where a solid is formed at the base of a liquid after separation with a liquid. Most of the time, settling the wastewater that was getting treated forms sediments.

Flocculation is a process focused on removal of the suspension. First, the pH of the wastewater needs to be established. This is done using a pH scale that ranges from zero to fourteen. If the pH is less than seven, a basic solution needs to be added to the water to achieve a pH of seven. If the pH is greater than seven, an acidic solution needs to be added to bring pH down to seven.

The reactions that occur form salt and water, where the salt will be the metal precipitate. Most of the flocculation processes that are done first by water are agitation or the addition of the flocculation agent. The use of the water has to be considered carefully before flocculation. Some of the flocculation agents added are toxic and are used for water that is not for human consumption but other industrial use. They have to be used based on the particles to be removed in the wastewater.

Secondary clarifiers should have an energy dissipater inlet to avoid disturbance of the elaborate sedimentation. Sludge withdrawal system is important to keep the clarifier as less clogged as possible and finally have a full surface skimmer. Assignment 2: Concepts and Web Exercise Due: 17th Dec 2016 (Week 12) (or as instructed by your local lecturer) Length: 1500 words Weighting: 30% Answer the following questions: 1) Provide examples of how real world multinational corporations (MNC) reduce their translation, transaction and economic exposures. (6 marks) 2) Explain the difference between foreign direct investment (FDI) and portfolio investment (PI). (4 marks) Collect the required data from the Bureau of Economic Analysis (BEA) website and answer the following questions: 3) List the ten largest countries by value of investment that invested in Australia in the years 2011 and 2014. You need to provide the list of countries as well as the amount of FDI invested in AUD. (5 marks) 4) What factors do you think account for these countries investing large amounts of FDI in Australia? (5 marks) 5) Have the list of investing countries changed over the concerned period? What might account for these changes? (5 marks) 6) Do you expect a change to the 2013 list over the next 5 years? Explain. (5 marks) This assignment is intended to test your knowledge of theories of exchange rates, parity conditions in international financial markets, the balance of payments and derivative markets. The assignment consists of four separate parts. The assignment is expected to be of standard quality with respect to spelling, grammar, punctuation, etc. Assignment submitted must be written in your own words and it must be your own work. It should not exceed 1500 words. Severe penalties apply for assignments, which exceed the word limit. The word count excludes references, tables and figures. If the assignment exceeds the word limit, then the following mark deductions will be applied.

Please note that the word limits are strictly enforced. Up to 5% excess – no deduction; more than 5% and less than 15% – 2 marks; more than 15% and less than 30% – 3 marks; over 30% – zero grade. Marking criteria include understanding of concepts (50%), support via graphs or math (30%), and presentation and referencing (20%).

Additional details involve needing to include writing from Unit I, discussion of ROI, and the intention to include physical, chemical, biological treatments, general sewage techniques, and solid waste treatment. Waste treatment involves physical, biological, and chemical techniques, which are often costly, requiring financial planning, staff management, certifications, and licensing (Bahadori, 2014).

Certification and licensing are crucial to ensure waste treatment does not pose health hazards to communities or workers. Physical and chemical waste treatments require operations and manual labor, with skilled personnel handling complex chemical processes. Equipment and personnel selection depend on waste characteristics and recovery goals (Baijpai, 2014).

Proper licenses and certifications from environmental authorities are essential before commencing waste treatment activities, ensuring regulatory compliance and safety standards (Bahadori, 2014). Additionally, assessing waste impacts on humans and ecosystems is necessary, especially for hazardous wastes, which are mainly generated by chemical industries (Bahadori, 2014). Understanding the chemical and physical sources of hazardous effluents helps in designing effective treatment systems and complying with legal standards (Hickman, 2003).

Distinguishing between hazardous and solid wastes is critical for appropriate management. Laws and standards guide safe waste handling, emphasizing environmental safety (Bahadori, 2014). Current waste management practices reveal that chemical industries produce significant hazardous waste, necessitating thorough process understanding for effective treatment (Bahadori, 2014; Haas & Vamos, 1995).

In the context of sewage treatment and hydrocarbon-laden liquid wastes, understanding hydrocarbon solubility, emission rates, and safety considerations is vital. Light hydrocarbons like methane and ethane are low-solubility gases that pose explosion risks due to their low flashpoints and emission during treatment processes (Hill & Feigl, 1987; Lewis, 1991). Accurate prediction of their solubility and vapor emission rates informs safety protocols and process design, preventing hazards from ignition sources.

Bahadori (2014) provides equations and coefficients to estimate the solubility and concentration of hydrocarbons such as methane and ethane in wastewater, which aids engineers in designing safer treatment facilities. Monitoring dissolved organic carbon (DOC) and chemical oxygen demand (COD) helps evaluate organic load and treatment effectiveness, with DOC to COD ratios guiding environmental impact assessments (Bahadori, 2014).

Effective biological and secondary treatments are key components in reducing pollutant concentrations, aligning treated effluents with municipal or regulatory discharge limits. Decision-making in equipment choice involves analyzing influent characteristics, predicted emissions, and safety concerns, especially regarding volatile organic compounds (Bahadori, 2014). The combination of physical, chemical, and biological treatments ensures comprehensive waste management tailored to specific waste types and environmental standards.

Paper For Above instruction

Wastewater treatment is an essential component of environmental management, designed to purify water for safe return to ecosystems or reuse. The two primary methods—chemical and biological treatment—are widely utilized due to their effectiveness; however, they often leave residual impurities, prompting the need for additional processes to achieve complete safety.

Flocculation, sedimentation, and coagulation are common supplementary processes applied after primary treatment stages. Coagulation involves adding chemicals—typically metal salts such as aluminum sulfate or ferric chloride—that destabilize colloidal particles by neutralizing charges, leading to the formation of larger aggregates or flocs. These flocs can be subsequently removed through sedimentation, where gravity causes them to settle at the bottom of sedimentation tanks or clarifiers. Proper design of these tanks, including energy dissipaters, is critical to prevent disturbance of settled sludge and to maintain operational efficiency (Hickman, 2003).

One pivotal aspect of chemical treatment is the adjustment of pH levels, which influences chemical reactions and floc formation. The pH scale ranges from 0 to 14; solutions below 7 are acidic, and those above are basic. Accurate pH measurement and control are necessary for optimal coagulation and flocculation processes. When the wastewater pH is below 7, alkaline solutions—such as lime or sodium hydroxide—are added to raise pH to neutral. Conversely, when pH exceeds 7, acids like sulfuric acid or hydrochloric acid are introduced to lower the pH (Bahadori, 2014).

The reactions involved typically produce salts and water, with salts often being metal precipitates that are removed physically. Toxic flocculants are sometimes employed in industrial settings where water is not intended for human consumption but for industrial reuse or discharge. The selection of suitable flocculants depends on the types of impurities present, the chemical properties of wastewater, and environmental considerations related to toxicity and disposal (Baijpai, 2014).

Secondary clarifiers further refine the process by allowing undissolved flocs to settle and be removed, preventing sludge buildup and maintaining system efficiency. The sludge withdrawal system also plays a crucial role in reducing clogging and facilitating regular maintenance. To minimize turbulence and disturbance, clarifiers are equipped with energy dissipaters at the inlet (Hickman, 2003).

In addition to physical and chemical processes, biological treatment exploits microbial activity to assimilate organic matter and convert pollutants into less harmful substances. Aerobic biological processes, such as activated sludge systems, are commonly employed, where microorganisms metabolize organic contaminants, reducing biochemical oxygen demand (BOD) and chemical oxygen demand (COD) significantly. These systems require careful aeration and monitoring to optimize microbial activity and ensure effluent quality meets standards (Hassan et al., 2005).

Design of biological treatment units involves selecting suitable reactors—such as aeration tanks and secondary clarifiers—and ensuring proper nutrient balance for microbial growth. The biological process’s efficacy depends on factors like temperature, pH, dissolved oxygen levels, and the characteristics of influent wastewater (Hickman, 2003). The comprehensive waste management system integrates physical, chemical, and biological treatments, aiming to reduce toxicity, organic load, and pathogen presence.

Environmental safety is paramount, especially concerning hazardous and industrial wastes. These wastes often contain volatile organic compounds (VOCs), such as hydrocarbons like methane and ethane, which are emitted during treatment and pose explosion and health risks. Understanding the solubility, volatility, and emission rates of these compounds enables engineers to design safer treatment facilities. For instance, light alkanes with low solubility are prone to gaseous emissions; thus, appropriate ventilation and monitoring systems must be installed (Hill & Feigl, 1987; Lewis, 1991).

Bahadori (2014) provides valuable equations to estimate hydrocarbon-water solubility, which supports safety assessments. For example, predicting the dissolved organic carbon (DOC) based on chemical oxygen demand (COD) offers insight into organic pollutant loads, facilitating effective treatment design. A typical ratio of DOC/COD — approximately 0.267 — allows estimation of organic content in wastewater, ensuring that biological systems can be tailored for maximum pollutant removal (Bahadori, 2014).

Combining these treatment strategies—physical, chemical, and biological—establishes a comprehensive wastewater management system capable of producing high-quality effluent that complies with environmental regulations. Proper engineering, operational practices, and safety protocols ensure the protection of both human health and ecological systems, ultimately fostering sustainable industrial practices.

References

• Bahadori, A. (2014). Waste management in the chemical and petroleum industries. Wiley.
• Baijpai, S. K. (2014). Environmental Engineering: Principles, Planning, and Practice. CRC Press.
• Hassan, M., et al. (2005). Wastewater Treatment Technologies. Environmental Science & Technology Journal.
• Hickman, H. L. (2003). American alchemy: The history of solid waste management in the United States. Forester Press.
• Haas, C., & Vamos, R. (1995). Hazardous and industrial waste treatment. Prentice Hall.
• Hill, F., & Feigl, D. (1987). Chemistry and life: An introduction to general, organic, and biological chemistry. MacMillan.
• Lewis, R. (1991). Hazardous chemicals desk reference (2nd ed.). Van Nostrand Reinhold.
• Haas, C., & Vamos, R. (1995). Hazardous and industrial waste treatment. Upper Saddle River, NJ: Prentice-Hall.
• Hickman, H. L. (2003). American alchemy: The history of solid waste management in the United States. Santa Barbara, CA: Forester Press.
• Hill, F., & Feigl, D. (1987). Chemistry and life: An introduction to general, organic, and biological chemistry. New York, NY: Macmillan.