Manufactured Water: Leading the Way in Water Sustainability

Water scarcity has become a pressing global concern, impacting billions of individuals. With traditional water sources depleting and climate change exacerbating the situation, the need for innovative solutions to meet the rising demand for freshwater has become crucial. As humans, we cannot create water, only nature can. But what we can do is to produce purified water from unconventional sources such as wastewater, seawater, and industrial effluents, a concept that can be called as Manufactured Water.

This is considered to be a viable solution to address water scarcity challenges for several reasons. Firstly, it reduces dependence on traditional freshwater sources, thus reducing pressure on already stressed water supplies. Secondly, by utilizing non-traditional water sources, manufactured water helps to diversify water resources and reduce the impact on sensitive ecosystems. Additionally, manufactured water offers a reliable and consistent supply, irrespective of seasonal variations or geographical limitations.

Manufactured water is produced through various advanced treatment technologies that purify and remove pollutants and contaminants from non-potable water sources. These sources may include municipal wastewater, industrial effluents, brackish groundwater, and Seawater. The treatment processes involved can include ultra-filtration, reverse osmosis, advanced oxidation, disinfection, and pH adjustment. By employing multiple treatment stages, water can achieve potable quality that meets or exceeds regulatory standards.

Promoting Recycle & Reuse and Desalination:

Treated wastewater, once considered a liability, has now emerged as a resource in addressing the crisis in Bangalore, by supplying secondary treated water for non-potable purposes and replenishing drying lakes. It’s high time for us to understand the importance of water reuse and recognize it as a powerful tool in mitigating these challenges, offering a practical and environmentally responsible approach to water management.

In times of abundant supply, the significance of treated water often goes unnoticed. However, in situations like the current crisis, there’s no hesitation in utilizing treated water, as it becomes a necessity. It’s crucial for us to understand that wastewater treated with best practices and technologies can meet potable water standards. Despite psychological barriers, if not for drinking, treated water can still be utilized for various non-potable and household purposes.

One major challenge associated with Water Reuse lies in perception of using the treated wastewater, the acceptance of this relies heavily on public perception and the establishment of stringent regulatory frameworks. To ensure public trust, comprehensive education and communication campaigns are essential to inform communities about the treatment processes and safety standards applied during the process. Moreover, stringent regulations and monitoring programs must be in place to guarantee compliance with quality parameters and address any potential health concerns.

Desalination is another key aspect of manufactured water, particularly in regions where freshwater resources are scarce and have coastal access. It involves the removal of salt and other impurities from seawater, making it suitable for various potable and non-potable purposes. It is considered to be the most viable source for fresh water in coastal regions for potable, Industrial and other manufacturing purposes where highest quality water is essential for production. Desalination can be expensive in terms of CAPEX and OPEX compared to other conventional water sources, necessitating investment and cost optimization measures. But it is considered to be most effective option in the regions having coastal lines and are water stressed.

Current Applications & Going Forward:

Manufactured water is already being successfully implemented in several regions worldwide. For instance, the city of Windhoek in Namibia has got the world’s first-ever direct potable reuse plant in 2002, an achievement pioneered by WABAG, this state-of-the-art facility now fulfils a substantial 35% of Windhoek’s total water consumption, solidifying its reputation as a remarkable solution.

In India, cities facing severe water scarcity, such as Chennai, have embraced manufactured water as a sustainable solution. WABAG has played a significant role in implementing several projects in Chennai, including a 45 MLD Treatment and Tertiary Reverse Osmosis (TTRO) plant for industrial use, a 110 MLD desalination plant for potable consumption, and currently executing a 400 MLD desalination plant. Additionally, WABAG has built numerous facilities for various industries and utilities in India and globally, further demonstrating its expertise and contribution to water sustainability efforts.

Given the ongoing advancements in technologies and efforts for optimising CAPEX and OPEX, the adoption of manufactured water as an alternative is expected to increase. It has the potential to transform water management practices globally, especially in water-stressed regions, providing a reliable and resilient water supply for communities, industries, and agriculture.

Conclusion:

Manufactured water offers a promising solution to combat water scarcity India and globally by tapping into non-traditional water sources and employing advanced treatment technologies. With its potential for Water Reuse & Desalination, manufactured water represents a crucial step towards achieving water security in view of SDG 6. As we navigate the challenges of the future, the significance of manufactured water will continue to grow, playing a crucial role in securing access to clean water for future generations.

2024 Water for Peace: Nurturing Global Harmony Drop by Drop

As we gear up to celebrate World Water Day on March 22nd, it is imperative to reflect on the pivotal role water plays in fostering global peace and stability. At the heart of this discourse lies the fundamental principle of equitable access to water for all. In a world where millions still lack access to clean water, ensuring universal availability not only addresses a basic human need but also lays the groundwork for conflict prevention and sustainable development. Competing demands for water resources frequently lead to disputes, both within and between countries. From the Nile River basin to the Indus River system, conflicts over water rights have the potential to escalate into full-blown crises, disrupting lives and livelihoods and perpetuating cycles of poverty and instability.

Technology emerges as a key ally in our quest to make water accessible to everyone. From remote sensing to data analytics, innovative solutions are revolutionizing water management, enabling us to monitor water resources more effectively and optimize their use. Similarly, advances in water purification technologies, such as membrane filtration, desalination, advanced oxidation technologies and ultraviolet disinfection, hold the promise of providing safe drinking water to even the most remote communities.

Desalination emerges as a game-changer in regions grappling with chronic water scarcity. By harnessing the vast potential of our oceans, desalination technologies offer a sustainable solution to augment freshwater supplies. From the arid coastlines of the Middle East to the parched landscapes of California, desalination plants are transforming seawater into a vital lifeline, providing communities with a stable source of water even in the face of droughts and climate variability.

Wabag is playing a vital role globally by providing safe potable water through STPs and desalination facilities. Currently Wabag is producing 1.3 million m3 desalinated water per day. When it comes to wastewater treatment, it is treating whopping 27 million m3 per day. Coupling with its path to net zero emissions, Wabag has incorporated sustainable solutions in their sewage treatment plants to reduce greenhouse emissions. Drawing upon robust research and development, coupled with an unwavering dedication to innovation, Wabag has spearheaded an expansive array of solutions meticulously crafted to tackle the pressing issues of water conservation, optimization, recycling, and resource reutilization on a global scale.

Water is too precious to be used only once – Mr. Rajiv Mittal (CMD, VA Tech Wabag)

In light of the burgeoning challenges posed by escalating water scarcity and the imperative to foster sustainable resource management practices, the significance of water reuse in both industrial and municipal domains cannot be overstated. As elucidated through comprehensive research and empirical evidence, the adoption of water reuse strategies emerges as a quintessential solution to mitigate the mounting pressures on freshwater reservoirs while concurrently addressing the escalating demands of burgeoning populations and expanding industrial sectors. Through the judicious implementation of advanced treatment technologies and the formulation of robust regulatory frameworks, the potential of water reuse to alleviate strain on conventional water supplies becomes increasingly apparent. Moreover, the imperative lies in fostering a paradigm shift in societal perceptions towards embracing water reuse as an indispensable component of water management strategies, thereby heralding a sustainable trajectory towards safeguarding our planet’s most precious resource for future generations.

As we commemorate World Water Day, let us recommit ourselves to the noble cause of ensuring water for all. By harnessing the power of technology, embracing water reuse practices, sustainable water management practices, and fostering cooperation among nations, we can pave the way for a future where water becomes a source of unity rather than division. When everyone has equitable access to water, we lay the foundation for a world free from chaos and conflict, where peace and harmony prevail.

Let us raise a toast to water – the ultimate peacemaker in our quest for a better world. Happy World Water Day!

In the pursuit of a sustainable future, green hydrogen has emerged as a promising solution for clean energy production. As the world strives to reduce greenhouse gas emissions and shift away from fossil fuels, the role of water in the production of green hydrogen cannot be overstated. Water, a seemingly ordinary substance, becomes a vital component in the quest for a greener and more sustainable energy landscape.

In the production of green hydrogen, the quality of water used is an important factor that can impact the efficiency and overall sustainability of the process. While water itself is a renewable resource, certain considerations need to be taken into account regarding its quality to ensure optimal performance and minimize potential issues.

Impact of Water Quality on Green Hydrogen Production

In green hydrogen production, one primary concern is the purity of the water. Impurities present in the water can have adverse effects on the performance and longevity of the electrolyzer used in the electrolysis process. High levels of impurities, such as minerals, salts, and contaminants, can lead to the formation of deposits or scale on the electrodes, reducing their effectiveness and increasing energy consumption. Therefore, water purification or treatment processes may be necessary to achieve the desired purity levels.

The conductivity of the water is another crucial aspect. Water acts as an electrolyte in the electrolysis process, facilitating the movement of ions. However, if the water’s conductivity is too low, it can impede the efficient flow of ions and hinder the electrolysis process. On the other hand, excessively high conductivity can result in increased energy consumption and electrode degradation. Therefore, achieving an optimal level of conductivity is essential for maximizing the efficiency of green hydrogen production.

In some cases, the source of water can also influence its quality. For instance, seawater contains a higher concentration of salts and minerals compared to freshwater sources. While seawater can be used for electrolysis, additional purification steps, such as desalination, may be required to reduce the impact of these impurities on the electrolyzer’s performance.

To ensure the quality of water used in green hydrogen production, continuous monitoring and periodic analysis are essential. Regular testing can help identify any changes in water quality, allowing for adjustments or corrective measures to be implemented promptly. Water treatment technologies, such as filtration, reverse osmosis, or ion exchange, can be employed to remove impurities and maintain optimal water quality throughout the process.

Alternative water sources for Green Hydrogen Production

The production of green hydrogen requires water for the electrolysis process, and as water scarcity becomes increasingly prevalent, it is essential to address the potential impacts and explore sustainable solutions. Advanced technologies, such as high-efficiency electrolyzers and water recycling systems, can minimize water consumption and enhance overall water efficiency. By implementing water-saving measures, the amount of water required per unit of hydrogen produced can be significantly reduced.

Additionally, alternative water sources can be explored to alleviate the pressure on freshwater resources. Seawater, for example, is an abundant and underutilized resource that can potentially be employed for green hydrogen production. However, it should be noted that utilizing seawater may necessitate additional steps for desalination and water treatment to ensure the appropriate quality and prevent damage to the electrolyzer.

Another aspect to consider is the integration of green hydrogen production with water management strategies. For instance, co-locating green hydrogen facilities with wastewater treatment plants or industrial processes that generate water as a byproduct can help minimize the strain on freshwater supplies. By utilizing treated wastewater or other non-potable water sources, the demand for freshwater in green hydrogen production can be reduced, promoting a more sustainable water cycle.

WABAG has been a frontrunner in providing the best and latest technology for water and wastewater treatment. Drawing from its decades of experience, WABAG has built wastewater treatment and reuse infrastructure to effectively treat 30 million m3 and reuse 2.5 million m3 of wastewater each day. WABAG has the expertise to provide the maximum quality of water required in green hydrogen production to increase the efficiency, performance, and lifespan of the electrolysis process. By carefully managing and maintaining water quality, WABAG can maximize the production of green hydrogen.

WABAG could not only help in saving freshwater resources by providing the highest quality of treated and desalinated water for green hydrogen production but also help in green hydrogen plant decentralization across the country. Decentralization of green hydrogen plants will result in saving the transportation and storage cost. This will result in a reduction in hydrogen production cost per KG.

Water scarcity is looming large among arid and coastal regions since a couple of decades. Desalination, the process of removing salt and other impurities from seawater or brackish water to produce fresh water, has become a subject of considerable interest as a perennial and viable solution to water scarcity. While it offers the promise of addressing water shortages in arid regions and coastal areas, there are debates surrounding the implications and impact of large-scale desalination operations. Here let us explore how desalination is a panacea to many people living in water scarce and water stressed regions in the world.

• Water supply security: Desalination provides a reliable source of freshwater that is not dependent on rainfall or surface water availability. It offers a solution to regions facing chronic water scarcity, ensuring a consistent water supply for domestic, agricultural, and industrial purposes.
• Diversification of water sources: By utilizing seawater or brackish water sources, desalination diversifies water supplies, reducing reliance on limited freshwater resources. This can help alleviate the pressure on groundwater reserves and protect ecosystems from over extraction.
• Enhanced resilience to climate change: Desalination can enhance resilience to climate change impacts, such as prolonged droughts and changing precipitation patterns. It offers a potential buffer against water shortages, particularly in regions vulnerable to climate-related water stress.
• Energy consumption: Desalination processes, particularly reverse osmosis, are energy-intensive. But with greener solutions coming into picture, simultaneously improving the efficiencies of the processes, this negative effect can be minimized and can be brought to zero in near future.
• Concentrate disposal: The concentrated brine, a byproduct generated during desalination requires proper disposal. Innovative solution for brine disposal, such as brine dilution to be in place.
• Cost and affordability: Desalinated water is of course more expensive than traditional freshwater sources. But, there are certain regions where the rate of evaporation is greater than rate of precipitation, desalination plays a key role in providing the best quality water in affordable prices for certain communities or developing countries with limited financial resources.

In conclusion, desalination offers an alternative solution to water scarcity, providing a reliable and diversified source of freshwater. By integrating renewable energy sources, improving desalination technologies, and better brine disposal offers a viable solution to water scarcity in water arid regions and coastal areas in the world.

In the current era of rapid technological advancements, Water industry has also been witnessing a surge of innovations based on Artificial Intelligence. Artificial Intelligence, driven by machine learning and data analysis, is playing a pivotal role in reshaping water treatment processes. This fusion of Artificial Intelligence with Water Treatment is bringing in a transformative wave of digital innovation, which is redefining the conventional way of designing and operating treatment plants, resulting to make the process more efficient, sustainable, and data-driven.

Traditionally, water treatment plants have relied on human intelligence, where design recommendations and operating decisions are made through manual analysis of historical data using conventional technologies and software. While these methods have been effective, they are often labor-intensive and limited in their ability to provide real-time insights, more options and predictive capabilities. However, when we combine Human Intelligence and Historical Data with Artificial Intelligence, decisions become data-driven, where AI algorithms can analyze vast amounts of data, identify patterns, and make analysis that might escape human observation.

Benefits of AI integration in Water Treatment are substantial

• Design Efficiency: AI Algorithms and Decision Trees can provide the most accurate recommendations, analyzing the historical design data, saving resources and time while allowing us to select the best option based on our requirements
• Operations Efficiency: AI can optimize the treatment process by predicting water quality parameters, adjusting chemical dosages, and managing energy consumption in real-time
• Predictive Maintenance: AI transforms maintenance from scheduled to predictive, predicting equipment failures and recommend proactive maintenance, minimizing downtime and extending the life of equipment
• Real-time Monitoring: A continuous real-time monitoring of water quality, allowing for early detection of contamination events and prompt responses to ensure the safety of treated water
• Cost Savings: AI driven optimizations lead to cost savings through reduced energy consumption, optimized resource utilization, and more efficient treatment processes
• Sustainability: This will aid in sustainable water treatment by reducing waste, conserving resources, and minimizing the environmental impact of treatment processes.

Challenges and the Role of Human Expertise

One major challenge associated with AI based solutions is the input data. The accuracy and quality of the data used for training and decision-making are of crucial importance. These systems heavily rely on historical and real-time data to make predictions, optimize processes, and ensure the safety and efficiency of water treatment plants. If the input data is inaccurate, incomplete, or biased, it can lead to incorrect recommendations and less than ideal decisions.

For example, if water quality data used by the AI model contains errors or is not representative of the actual conditions, the model’s predictions may be unreliable. Similarly, if the training data doesn’t cover a wide range of scenarios and historical data, the AI algorithm might struggle to address uncommon situations.

This is where human expertise plays a crucial role, in data validation of input data and decision validation of the given recommendations, as process experts can identify suboptimal recommendations and make the final decisions for implementing based on their domain knowledge and experience. Additionally, they can continuously refine AI models by providing feedback and updating the algorithms to adapt to changing conditions and evolving industry standards.

Way Forward

While we may not currently have a AI technology that can fully automate the treatment plants without human intervention, that day is not far off. Looking ahead, the future of AI in water treatment facilities is promising. As technology continues to advance, we can expect more sophisticated solutions, including autonomous treatment systems, deeper integration with renewable energy sources, and even more advanced predictive capabilities for water quality and infrastructure maintenance.

AI is at the forefront of reshaping water industry, particularly in sewage treatment, wastewater treatment, desalination, and water reuse plants. By utilizing the power of AI, we have the potential to create more efficient, sustainable, and resilient water treatment processes, ensuring the availability of safe and clean water for generations to come.

An aquifer is an underground layer of water-bearing permeable rock, rock fractures or unconsolidated materials. There are two general types of aquifers: confined and unconfined. Confined aquifers have a layer of impenetrable rock or clay above them, while unconfined aquifers lie below a permeable layer of soil. In order to access this water, a well must be created by drilling a hole that reaches the aquifer. While wells are man made points of discharge for aquifers, they also discharge naturally at springs and in wetlands. Aquifers are natural filters that trap sediment and other particles (like bacteria) and provide natural purification of the ground water flowing through them.

Aquifer recharge (AR) and aquifer storage and recovery (ASR) are man made processes or natural processes enhanced by humans that convey water underground. The processes replenish groundwater stored in aquifers for beneficial purposes. AR is used solely to replenish water in aquifers. ASR is used to store water, which is later recovered for drinking water supplies, irrigation, industrial needs, or ecosystem restoration projects. Injecting water into AR wells can prevent saltwater intrusion into freshwater aquifers and control land subsidence.

Several methods of introducing water into an aquifer exist including surface spreading, infiltration pits & basins and injection wells. Injection wells are used for AR and ASR in areas where surface infiltration is impractical. Aquifers can be recharged from rain water, river water, recycled water, etc.

Groundwater is one of our most valuable resources. Aquifers are nature’s storage tanks provided to mankind. We see a lot of river water being discharged to sea, during every monsoon, without being used. If the rain water & river water are effectively used for recharging aquifers, the ground water availability can be enhanced and Aquifer stored water recovered can be used to alleviate the water shortage.

Groundwater is invisible, but its impact is visible everywhere. Out of sight, under our feet, groundwater is a hidden treasure that enriches our lives.

Almost all of the liquid freshwater in the world is groundwater. Groundwater provides almost half of all drinking water worldwide, about 40% of water for irrigated agriculture and about one third of water supply required for industry.

It sustains ecosystems, maintains the base flow of rivers and prevents land subsidence and seawater intrusion. Despite its importance, groundwater is invisible. In addition, out of sight often means out of mind.

As climate change gets worse, groundwater will become more and more critical. We need to work together to sustainably manage this precious resource. There are also some strategies to promote sustainable groundwater supply. Conjunctive use of surface water and groundwater, desalination, recycling and wastewater reuse, water harvesting, increase recharge to the groundwater system are few effective measures to promote sustainable groundwater supply.

Groundwater may be out of sight, but it must not be out of mind. The theme of groundwater should be able to shape the campaign through suggestions of activities but also get the information and the tools needed to raise awareness of groundwater in all public forums.

The theme of groundwater will contribute to a raised public, policy and scientific awareness of the opportunities and risks of addressing groundwater in the context of achieving sustainable development goals. WABAG, the world market leader in the water industry, always stands in front for giving all necessary support in achieving this goal.

Finite in water resources and end users stringent deliverable creates huge pressure on this segment which necessitates water treatment industries to deliver more efficiently including safe and secure drinking water, storm water management and waste water management. Water crisis has been indicated as one of the main global risks due to the climate change. Pandemic affected the water treatment and waste water treatment segment also. Also the pandemic didn’t spare the water industry and many people in the treatment plants were affected, which led to skeletal resources operating these huge facilities. Innovative approaches like Remote Monitoring, extensive usage of smart condition monitoring devices for the rotary equipment, application of IOT and by adopting smart monitoring sensors improve service level sustainability and economic viability. Digitization in water segment also helped in sync with other utilities like power, transport and disaster management. This leads to the operational continuity in the scheme of things.

Generally, water & waste water treatment plants in municipal and Industry are operated through SCADA (Supervisory control and Data acquisition) and PLC (Programmable Logic Controller) with sufficient interlocks and with all safety features. During this global Pandemic, to mitigate the risk of the skeletal manpower at site, one of the solutions that has come handy is to monitor the plant performance at a centralized Network operations center located at a remote location. Process experts can monitor the multiple plants located at different parts of the world. In case any abnormality is observed in the plant performance from these remote locations, an alert is issued to the site team and also provides solutions to the problems. This methodology has also been used extensively in virtual commissioning of the equipment, besides the process monitoring of the plant.

IOT’s have become handy and are being extensively used in process analyzers and instruments which can provide Real time data, trends, escalation matrix and can also communicate to the centralized monitoring stations. Presently, manual log sheets are becoming obsolete and digital log sheets, which are automatically generated from system are preferred which is an authentic data. IOT supports OPEX costs like optimizing chemicals, power, utilities and reducing wastage.

The increasing complexity in various technologies necessitates a paradigm shift to the next generation and water systems beyond conventional water and sewerage water. Conditional based monitoring services can work with all the water automation products for gaining access to real time data via cloud from remedial loaded water assets as this drives the sector shift from reactive to real time monitoring. Above digital interventions definitely involve CAPEX, however OPEX will be reduced drastically for long term plant operations. On the other hand, this will improve the reliability of equipment and plants. It is imperative that awareness and familiarization of these technologies have to be focused in various forums and webinars.

Digitization & Artificial intelligence ensures Operational excellence by way of:

• Lesser machinery breakdown due to usage of IOTS, smart sensors and real time monitoring
• Lesser energy consumption on optimum energy usage
• Optimized Chemical Consumption
• Reduced water losses
• Reduced contamination of water bodies
• Improved customer satisfaction and transparent service level agreement
• Digitization solutions allows experts to analyze data collected from smart sensors and derive into corrective and confident action to extend equipment failure
• Digitization can trigger the earliest possible warning

Going forward, digitization and artificial intelligence will play a critical role in the water and wastewater treatment industry as well for ensuring Operational Excellence.

Our Planet Earth depends on the vitality of the ocean for sustenance in myriad ways. Ocean offers innumerable benefits to the mankind in terms of saltmarshes, mangroves, ocean currents, nutrient rich upwelling and other forms of life. As is well known, it provides for an alternative source of water which is reliable, perennial and viable and we, WABAG, with advanced technologies at its command, desalinate sea water into potable water for quenching the thirst of the citizens not only in India but also across the globe. Let us now see its other dimensions:

• The ocean produces over 50% of the world’s oxygen and stores 50 times more carbon dioxide than our atmosphere. The majority
  of oxygen production is from oceanic plankton — drifting plants, algae, and some bacteria that can photosynthesis. Ocean plays a major role in carbon cycle. Carbon is continually exchanged between the ocean’s surface waters and the atmosphere, or is stored for long periods of time in the ocean depths
• Covering 71% of the Earth’s surface, the ocean transports heat from the equator to the poles, regulating our climate and weather patterns
• 76 % Percent of world’s trade involving some form of marine transportation
• From fishing to boating to kayaking and whale watching, the ocean provides us with so many unique recreational activities
• Many medicinal products come from the ocean, including ingredients that help fight cancer, arthritis, Alzheimer’s disease, and heart disease
• Amount the U.S. ocean economy produces in goods and services is 282 Billion USD. Ocean- dependent businesses employ almost 3 million people
• The ocean provides much more than just seafood. Ingredients from the sea are found in surprising foods such as peanut butter and soymilk

Seawater contains large quantities of valuable minerals, some of which are very scarce and expensive in their land-based form. However, only a few minerals, the ones in high concentrations, are currently mined from the sea. Due to recent challenges with land-based mining industries, seawater mining is becoming an attractive option. The main ions which make up 99.9% of the salts in seawater in decreasing order are: Na⁺ > Mg²⁺ > Ca²⁺, K⁺ > Sr²⁺ (for cations) and Cl⁻ > SO4²⁻ > HCO3⁻ > Br⁻ > BO3²⁻ > F⁻ (for anions). Currently the four most concentrated metals – Na, Mg, Ca and K – are commercially extracted in the form of Cl⁻, SO4²⁻, and CO3²⁻. Mg is also extracted as MgO.

Deep sea mining is also growing that involves the retrieval of minerals and deposits from the ocean floor found at depths of 200 meters or greater. Presently, the majority of marine mining efforts are limited to shallow coastal waters, where sand, tin and diamonds are more readily accessible.

But our ocean faces major threats such as global climate change, pollution, habitat destruction, invasive species, and a dramatic decrease in ocean fish stocks. These threats to the ocean are so extensive that more than 40 percent of the ocean has been severely affected.

Let us minimize the threats to the ocean from Mankind so that ocean continues to offer its invaluable benefits to sustain our Planet Earth.

Water stress in different regions of India has made people to accept Seawater Reverse Osmosis (SWRO) desalinated water as an alternate solution to alleviate drought. However, the following myths and misconceptions still exists among a few. Clarifications are provided to overcome the myths and misconceptions.

Myth 01: Desalinated water from Municipal Desalination Plants do not have enough minerals and use of desalinated water depletes minerals from the body

SWRO plant’s design is flexible with modular and multistage arrangement to produce water of any required specification. Potable water produced is of high quality, reliable and free from bacteria and virus. The potable water from SWRO plants are designed to meet ISO 10500 standard or World Health Organisation (WHO) specification or they can be design to produce high purity Process water for Industries with Total Dissolved Solids (TDS) < 10 mg/l. Typical analysis of selected potable water parameters from a desalination plant are given below:

Hence, it is not true that potable water produced by the municipal SWRO plants do not have minerals.

Myth 02: Desalination plants kill fish and other marine life in that region

In designing desalination plants, protection of marine life is given priority. The Intake is designed providing large flow area so that water enters the Intake velocity head at very low velocity so that fish, fish eggs and other marine lives are not drawn inside. Intake velocity head is located deep inside sea. Hence, protection of marine life from being drawn along with seawater is ensured. Typical Intake velocity head arrangement is illustrated in figure 1 and 2.

Figure 1 : Intake velocity head (Bar Screen Type)

Figure 2 : wedge wire type Intake screen

Desalination Plant ensures that only salt water is discharged without any impurities or chemicals. The chemical cleaning solutions are neutralized before being discharged to the sea. Many plants remove sludge from the backwash waters before it is discharged in to the sea. The outfall discharge is located away from shore deep inside sea with the multiple nozzle diffuser design to recirculate the seawater and dilute the brine salinity closer to the seawater salinity at a radius of 50 meters, so that the fish and marine lives are not affected. The environmental protection agencies monitor the seawater quality close to the outfall.

Myth 03: Desalination Plants increase salinity of well water close to the shore

The recovery (percentage of low salinity water recovered from seawater) is in the range of 40 to 45%. The salt rejected from the 45% low salinity water separated in the RO plant is returned to the sea as brine along with 55% seawater. However, the brine gets diluted in salinity and it reaches close to the seawater salinity at a radius of 50 meters from the discharge point. Hence the salinity of the seawater near shore remains unaltered.

Myth 04: Desalinated water cost is very high and not affordable

The cost of water produced by desalination has come down considerably in the last 30 years due to developments in membranes with higher productivity, innovation in energy recovery devices, economy of high capacity units, more efficient higher capacity pumps etc. The O&M cost in Nemmeli 100 MLD desalination plant owned by CMWSSB and being Operated and Maintained by VA Tech WABAG is Rs 39/m3. New desalination technologies are bound to reduce the cost of desalinated water further. Electric power cost which forms >75% of the O&M cost of a SWRO plant in India can be brought down further by using green energy, much lesser in cost compared to power from thermal power plant.

Myth 05: Desalination consumes more energy

In 1980s, SWRO consumed around 8.5 to 9 kWh/m3 of water produced. The plant recovery was in the range of 30 to 35% and the plant capacity was much less. However, today, with innovations in the energy recovery devices, RO membranes with high flux, high capacity plants with more efficient pumps, the energy consumption has come down to 3 to 3.5 kWh/m3. Research is being concentrated in development of new desalination technologies like Forward Osmosis and Membrane Distillation Process and advanced membrane technologies like Aquaporin & graphene to bring the specific power consumption further down.