India is adopting advanced sewage wastewater treatment tech, but must choose those that best meet local needs

Wastewater Treatment Technologies in India: A Report on Sustainable Development Goals

Introduction

Blindly embracing new technologies may not always be wise or provide the desired outcome. In the context of wastewater treatment and recovery, it is crucial to address water scarcity and environmental pollution. However, Indian cities currently treat only 28% of the 72,368 million litres of sewage they generate every day, as per the latest data released by the Central Pollution Control Board in December 2022.

Current Challenges and Outdated Technologies

While there is a clear need to increase treatment capacity, the currently employed wastewater treatment processes in India rely on outdated technologies such as the activated sludge process, planted drying beds, soil biotechnology, and upflow anaerobic sludge blanket reactors. These technologies have a treatment efficiency of around 65% and are cumbersome to set up and manage.

Adoption of New Technologies

Several states in India have started adopting newer technologies with treatment efficiency ranging from 80% to 90%. Sequencing batch reactors (SBRs) and moving bed biofilm reactors (MBBRs) are two such technologies that have been widely implemented. For instance, most sewage treatment plants set up in Andhra Pradesh and Telangana after 2018 are based on SBRs and MBBRs. Similar upgrades have been reported in Bihar, Maharashtra, Goa, Haryana, West Bengal, and Uttarakhand.

Advantages of New Technologies

Compared to traditional treatment techniques, SBRs and MBBRs offer higher treatment and nutrient removal capacity. They are better at handling shock loads in wastewater and are more resource-efficient. These technologies generate high-quality effluent with greater reuse potential.

Considerations for Technology Selection

However, blindly embracing new technologies may not be wise or provide the desired outcome. The choice between SBRs, MBBRs, and other technologies depends on project-specific considerations, including effluent quality requirements, land availability, energy requirements, and costs. Here is a checklist that will help administrators, companies, and townships identify the technology ideal for their needs:

1. Effluent quality requirements
2. Land availability
3. Energy requirements
4. Costs

Membrane Bioreactor (MBR)

MBR is a wastewater treatment technology that combines biological processes with a membrane for high filtration rates. While highly efficient, MBRs are energy-intensive and expensive to set up and operate. They require regular maintenance, skilled human intervention, and frequent system downtime to replace the membrane. MBRs are imperative for industries like food processing that need to achieve zero-liquid discharge.

Moving Bed Biofilm Reactor (MBBR)

MBBR is extensively used for handling municipal sewage. It is a type of wastewater treatment process that takes place in a bioreactor with plastic carriers on which microorganisms can attach and thrive. MBBRs have high treatment efficiency, low energy consumption, and negligible downtime. However, they have limitations in terms of limited removal of solids and nutrients.

Sequencing Batch Reactor (SBR)

SBRs combine biological treatment and sedimentation within a single bioreactor. They offer flexible operation, precise control over treatment parameters, and the capability to achieve enhanced nutrient removal. SBR systems require smaller reactor volumes compared to continuous flow systems, reducing both the footprint and construction costs. However, SBRs have longer treatment cycles, generate a significant amount of sludge, and require advanced process control systems.

Conclusion

Choosing the right wastewater treatment technology is crucial for addressing water scarcity and environmental pollution. While new technologies like MBRs, MBBRs, and SBRs offer higher treatment efficiency and resource efficiency, careful consideration must be given to project-specific requirements. Effluent quality, land availability, energy requirements, and costs should be taken into account to make an informed decision. By adopting sustainable wastewater treatment technologies, India can contribute to achieving the Sustainable Development Goals (SDGs) related to clean water and sanitation.

Authors: Atun Roy Choudhury, Neha Singh, P Sankar Ganesh, Resham Bhalla, K Mahalakshmi, K Sandhya

SDGs, Targets, and Indicators

SDGs addressed or connected to the issues highlighted in the article:

1. SDG 6: Clean Water and Sanitation
2. SDG 9: Industry, Innovation, and Infrastructure
3. SDG 11: Sustainable Cities and Communities
4. SDG 12: Responsible Consumption and Production

Specific targets under those SDGs identified based on the article’s content:

• SDG 6.3: By 2030, improve water quality by reducing pollution, eliminating dumping and minimizing release of hazardous chemicals and materials, halving the proportion of untreated wastewater and substantially increasing recycling and safe reuse globally.
• SDG 9.4: By 2030, upgrade infrastructure and retrofit industries to make them sustainable, with increased resource-use efficiency and greater adoption of clean and environmentally sound technologies and industrial processes.
• SDG 11.6: By 2030, reduce the adverse per capita environmental impact of cities, including by paying special attention to air quality and municipal and other waste management.
• SDG 12.4: By 2020, achieve the environmentally sound management of chemicals and all wastes throughout their life cycle, in accordance with agreed international frameworks, and significantly reduce their release to air, water and soil in order to minimize their adverse impacts on human health and the environment.

Indicators mentioned or implied in the article that can be used to measure progress towards the identified targets:

• Treatment efficiency of sewage treatment plants (indicates progress towards SDG 6.3)
• Adoption of newer technologies with higher treatment efficiency (indicates progress towards SDG 9.4)
• Upgrade and replacement of outdated sewage treatment plants with newer technologies (indicates progress towards SDG 11.6)
• Reduction in pollution concentration in wastewater (indicates progress towards SDG 12.4)

Table: SDGs, Targets, and Indicators

Behold! This splendid article springs forth from the wellspring of knowledge, shaped by a wondrous proprietary AI technology that delved into a vast ocean of data, illuminating the path towards the Sustainable Development Goals. Remember that all rights are reserved by SDG Investors LLC, empowering us to champion progress together.

Source: downtoearth.org.in

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