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RO Demand Across India: Busting Common Perceptions
Access to safe drinking water (Fig. 1) is vital for public health. Safe water is free from harmful contaminants, pathogenic bacteria, agricultural inputs like pesticides, heavy metals and high TDS. In India, 70% of water sources are contaminated, affecting over 600 million people and causing 200,000 deaths annually.
The World Health Organization (WHO) establishes international standards for safe drinking water quality, considering various parameters like chemical, microbiological, and radiological contaminants to protect public health. These guidelines provide a framework for countries to develop and implement their own national drinking water quality standards.
The Bureau of Indian Standards (BIS) sets standards for safe drinking water in India.
Fig. 1 BIS-10500 desirable and permissible limits in drinking water.
Image Source: https://jaljeevanmission.gov.in/
Water Purification Methods
Sediment Filters: Effective in pre-filtration for turbid water, capturing dust, sand, and rust particles before further purification.
Ultraviolet (UV) Filtration / Ultrafiltration (UF): It is suitable for microbiologically unsafe water with low TDS. It eliminates bacteria and viruses but does not remove dissolved impurities. Ultrafiltration, similar to UV, targets bacteria and viruses, often used in conjunction with other filtration methods for more comprehensive purification.
Reverse Osmosis (RO): Best for high-TDS water, including borewell or municipal water with heavy metals and fluoride. Although it removes essential minerals and bacteria, it also wastes water during purification.
Among these, RO filtration is the most widely used (Fig. 2) in India due to its ability to remove a broad range of impurities and filter out high TDS content.
Fig. 2 Water Purifier Market
Understanding Reverse Osmosis
An RO system works like a very fine sieve, using a semi-permeable membrane with tiny holes to filter out impurities from water.
Reverse Osmosis (RO) is a filtration process where high-pressure water is forced through a semi-permeable membrane. Water is moved from a high concentration to a low concentration, separating impurities and generating pure water. This process filters out dissolved solids like salts and minerals, significantly reducing the Total Dissolved Solids (TDS) and making the water taste better (Ref. Fig 3).
Removes up to 99% of impurities: Eliminates harmful substances like chlorine, arsenic, and fluoride.
Eradicates bacteria and viruses: Prevents waterborne diseases by blocking pathogens. Reduces TDS,
improving taste and clarity: Enhances water’s overall quality by removing excess minerals like sodium and magnesium.
Despite its benefits, RO filtration comes with certain drawbacks:
High water wastage: Produces approx. 2-3 liters of wastewater per liter of purified water.
Significant energy consumption: Requires consistent electricity, making it less viable in areas with power shortages.
Expensive maintenance: Requires periodic membrane replacements and servicing.
Infrastructure limitations: Remote areas may lack the plumbing and electricity required for installation.
RO in Urban Areas: Is it Necessary?
While RO systems provide excellent filtration, their necessity depends on water quality. Urban water is already treated, making RO optional, whereas rural sources often contain higher contaminants, making it more essential.
Understanding the differences in water quality and common perceptions surrounding RO systems can help you decide whether they are a necessity or an unnecessary expense. RO systems are particularly beneficial in areas with high TDS levels, as they effectively reduce TDS to safe, drinkable levels, ensuring clean and purified water for everyday use.
Water Quality in Urban Areas
Urban water is primarily supplied by municipal systems, which undergo treatment to meet safety standards. However, contamination can occur due to ageing pipelines, leading to the presence of chlorine, heavy metals, or fluoride. These contaminants may cause serious health problems.
The presence of these contaminants in urban water supplies highlights the importance of regular monitoring and maintenance of water infrastructure to ensure the continued delivery of safe and high-quality drinking water to city dwellers.
Common Perceptions about RO in Urban Areas
- RO filtration as essential for urban areas: Many people perceive RO filtration as essential for urban areas. However, municipal water is already treated and generally safe for consumption. In addition, drinking water source of most of the urban areas is the lakes or dams, where the water is already low on TDS. This makes RO unnecessary in most cases. Moreover, RO can strip away beneficial minerals like calcium and magnesium, which are important for health. In urban settings, alternative filtration methods, such as UV or activated carbon filters, are often sufficient to maintain water quality while preserving essential minerals.
- RO enhances water taste: It is commonly perceived that RO enhances water taste and quality in urban areas. While it can improve taste in regions with high TDS, it is not always necessary for treated municipal water. Alternatives like UV or UF filtration effectively remove impurities while retaining essential minerals, ensuring safe and high-quality drinking water.
Water Quality in Rural Areas
Rural households often rely on sources like wells, rivers, and lakes for their water supply. These sources are more susceptible to contamination compared to treated municipal water.
Contaminants in rural water sources can include pesticides from agricultural runoff, harmful bacteria, and high levels of total dissolved solids (TDS), which can affect the taste and quality of the water. These contaminants can pose significant health risks to rural communities and may require the use of water treatment methods like filtration or disinfection to ensure safe consumption.
Common Perceptions about RO in Rural areas
- Rural areas not needing RO systems: Many people assume that rural areas do not need RO systems because they rely on natural water sources. However, groundwater in these regions often contains high levels of TDS, arsenic, and fluoride, which can pose serious health risks. RO filtration helps remove these contaminants, making the water safe for consumption.
- RO systems are too expensive: Another common belief is that RO systems are too expensive for rural households. In reality, cost-effective RO solutions are available, and the long-term health benefits outweigh the initial installation and maintenance costs, making them a valuable investment for safe drinking water.
Alternative Filtration methods in Rural areas
Reverse osmosis (RO) systems, while effective, can be costly and energy- intensive, making them unsuitable for many rural areas. Fortunately, there are several alternative filtration techniques that can provide safe and clean drinking water:
- Ceramic Filters: Affordable, easy to maintain, and remove bacteria.
- Sand Filters: Simple, low-cost, and remove suspended particles.
- Activated Carbon Filters: Improve taste and odour by removing organic matter and chlorine.
- UV Disinfection: Effective against bacteria and viruses.
- Solar Water Disinfection (SODIS): Uses sunlight to kill microorganisms.
- Water Softeners: Help reduce water hardness by removing calcium and magnesium, though they do not significantly lower TDS levels.
Conclusion
In conclusion, while urban areas can leverage existing infrastructure and explore alternative purification methods, rural areas heavily rely on RO technology as a primary and crucial solution to combat water contamination and high TDS and ensure access to safe drinking water.
At NICHEM, we understand the importance of accessible and affordable water purification solutions. Our range of filtration technologies is tailored to address the specific challenges of urban and rural communities. Visit our website to learn how we can help you secure safe and healthy drinking water not only for households, but also for industry.
