Vibhor Gupta.
Department of Biotechnology, Mahatma Jyoti Rao Phoole University, Jaipur, Rajasthan, India.
Abstract
This comprehensive review examines the necessity of proper sewage treatment and the balance required to optimize public health outcomes. Derived from observations made during an academic-industry collaborative student training program, this analysis explores the critical role of sewage treatment plants (STPs) in mitigating health risks posed by sewage water, the potential dangers of over-treatment, innovative treatment technologies, and recommendations for better regulation and monitoring. By connecting research findings to real-world applications, this review highlights the practical implications of effective sewage treatment.
Introduction
Sewage water, a complex mixture containing human waste, industrial effluents, and urban run-off, is teeming with harmful pathogens and contaminants that pose significant health risks to humans. Effective sewage treatment is crucial for mitigating these risks and ensuring the availability of safe, reusable water. Sewage treatment plants (STPs) play a vital role in this process by removing or neutralizing harmful substances, thus protecting public health and the environment. This review, based on an academic-industry collaborative student training program, delves into the importance of proper sewage treatment, the potential dangers of over-treatment, innovative treatment technologies, and the balance required to optimize public health outcomes.
Sewage treatment involves a multi-stage process aimed at removing contaminants from wastewater. Primary treatment removes solids, secondary treatment degrades organic matter using biological processes, and tertiary treatment eliminates remaining contaminants and pathogens. Effective sewage treatment significantly reduces toxic contaminants such as ammonia, nitrates, and heavy metals, and eradicates pathogens responsible for severe waterborne diseases like diarrhea, cholera, typhoid, giardiasis, and hepatitis A. This process ensures that water is safe for reuse, thereby preventing disease outbreaks and safeguarding public health (Ashbolt, 2004). Pathogens such as E. coli, Vibrio cholerae, Salmonella typhi, Giardia lamblia, and the Hepatitis A virus are commonly found in untreated sewage water. Without effective treatment, these pathogens can lead to widespread outbreaks of diseases, significantly impacting public health, particularly in densely populated areas (Thompson, 2004; Crump, Luby, & Mintz, 2004).
Risks of Over-Treatment
While the necessity of sewage treatment is evident, the process must be carefully balanced to avoid over-treatment, which can introduce new problems. Over-treatment can occur when biological or chemical processes are excessively applied, leading to unintended consequences such as the release of excess organic and inorganic matter into treated water. Excessive biological treatment can increase the biological oxygen demand (BOD) of the water, leading to oxygen depletion in aquatic environments and harming marine life (Bitton, 2011). Overuse of chemicals like chlorine can result in the formation of toxic compounds that pose health risks to humans and the environment (Richardson et al., 2007).
Biological over-treatment can lead to the proliferation of non-target microbial species, which can disrupt the ecological balance of water bodies. Similarly, excessive chemical treatment can lead to the formation of disinfection byproducts (DBPs), which are compounds formed when disinfectants react with organic matter in water. These DBPs, such as trihalomethanes (THMs), haloacetic acids (HAAs), and bromate, are potential carcinogens and pose significant health risks (Krasner et al., 2006).
Disinfection Challenges
Disinfection, a critical final stage in sewage treatment, aims to eliminate remaining pathogens. Common methods include chlorination and ozonation. However, if not carefully regulated, these processes can strip essential minerals and electrolytes from water, such as calcium, magnesium, and manganese, leading to adverse health effects. Additionally, disinfectants can react with organic matter in the water to form DBPs, which are known to have carcinogenic properties (Sadiq & Rodriguez, 2004).
Innovative Sewage Treatment Technologies
Recent advancements in sewage treatment technologies offer promising solutions to the challenges of effective sewage treatment:
Membrane Bioreactors (MBRs): Combining biological treatment with membrane filtration, MBRs effectively remove pathogens and contaminants, producing high-quality effluent. This technology is particularly useful in areas with stringent discharge standards and limited space for traditional treatment plants (Judd, 2008).
Constructed Wetlands: These engineered systems mimic natural wetlands to treat sewage. They use vegetation, soil, and microbial activity to remove contaminants, providing a cost-effective and sustainable treatment option, especially for rural and peri-urban areas (Vymazal, 2011).
Advanced Oxidation Processes (AOPs): AOPs utilize powerful oxidants like ozone, hydrogen peroxide, and UV light to degrade organic contaminants and pathogens. This technology is effective in breaking down persistent pollutants and is increasingly being integrated into tertiary treatment stages (Glaze, Kang, & Chapin, 1987).
Electrocoagulation: This process uses electrical currents to destabilize and remove suspended particles, heavy metals, and pathogens from sewage. It offers a versatile and efficient treatment method, particularly for industrial wastewater (Mollah et al., 2001).
One notable example is the implementation of MBR technology in Beijing, China, which has significantly improved the quality of treated wastewater, allowing it to be reused for urban non-potable purposes (Meng et al., 2009). Another example is the use of constructed wetlands in Uganda, where this sustainable technology has effectively treated sewage in peri-urban areas, reducing the prevalence of waterborne diseases (Kansiime & van Bruggen, 2001).
Recommendations for Better Regulation and Monitoring
To ensure the effectiveness and safety of sewage treatment processes, the following recommendations are proposed:
Standardized Monitoring Protocols: Implementing uniform monitoring protocols across treatment facilities to ensure consistent quality and compliance with regulatory standards. This can be facilitated through collaboration between regulatory bodies and treatment facilities (USEPA, 2006).
Real-Time Water Quality Monitoring: Utilizing advanced sensors and IoT technologies to enable real-time monitoring of water quality parameters, allowing for immediate adjustments and interventions (Kassinos et al., 2011).
Integrated Management Systems: Developing integrated management systems that combine data from various treatment stages to optimize process efficiency and detect potential issues early. These systems can also facilitate better decision-making and resource allocation (Tchobanoglous, Burton, & Stensel, 2003).
Public-Private Partnerships: Encouraging collaborations between government agencies, private companies, and research institutions to foster innovation and share best practices in sewage treatment. Such partnerships can lead to the development of more effective and sustainable treatment technologies (OECD, 2015).
Community Engagement: Educating communities about the importance of sewage treatment and involving them in monitoring and reporting water quality issues to enhance transparency and accountability. This can be achieved through public awareness campaigns and community-based monitoring programs (Rosenqvist, Mitchell, & Willetts, 2016).
Discussion
The effective treatment of sewage is a cornerstone of public health. Achieving the right balance in treatment processes is essential to avoid the risks associated with over-treatment. Biological over-treatment can lead to oxygen depletion in water bodies, adversely affecting aquatic ecosystems. Chemical over-treatment, on the other hand, can produce toxic byproducts and strip essential minerals from water, leading to significant health risks. Continuous research and innovation in sewage treatment technologies are essential. Developing advanced treatment methods that can efficiently remove contaminants without causing over-treatment is a key area of focus. Additionally, better regulation and monitoring systems are needed to ensure treatment processes are optimized for both effectiveness and safety.
Conclusion
Sewage treatment is vital for protecting public health and the environment. Effective treatment processes can remove harmful pathogens and contaminants, making water safe for reuse. However, careful regulation and monitoring are essential to avoid the adverse effects of over-treatment. By striking the right balance in treatment processes, we can ensure the safe and sustainable management of wastewater, safeguarding human health and environmental integrity.
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How to Cite This Article:
Gupta V. (2024, July 16). Balancing Sewage Treatment: Risks, Innovations, and Recommendations. Convergence Insight. Retrieved from https://www.convergenceinsights.co.uk/post/balancing-sewage-treatment-risks-innovations-and-recommendations
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