The rising levels of water pollution across the globe due to rapid urbanization, industrialization, and climate change has led to increased mortality rates, owing to water-borne diseases. Unfortunately, toxins, chemicals, and pathogens are some of the contaminants that can make tap water unsafe for consumption. Even boiling water for more than 20 minutes can not remove pathogens and hazardous chemicals, causing poor health and diseases. With increasing awareness towards health and rising incidences of water-borne diseases, there have been a rise in demand for Point-Of-Entry water purification systems, which are designed to treat water for safe consumption. Filtering water not only eliminates a wide range of contaminants from drinking water but also makes the water taste and smell better. Water filters also reduce the risk of certain cancers such as bladder cancer, rectal cancer, colon cancer, etc. by eliminating chlorine and chlorine by-products and acts as a defence against 21,00 known toxins. POE water filtration systems are also known as “whole home systems” as they filter water that comes to your home or business and filter it all by removing contaminants.

Point of Entry (POE) Water Purifiers Based on Technology 

1. Membrane Based Water Purifiers

· Micro-filtration (MF) Water Purifiers

· Ultra-filtration (UF) Water Purifiers

· Reverse Osmosis (RO) Water Purifiers

· Nanofiltration (NF) Water Purifiers

2. Ultraviolet Based Water Purifiers

3. Media Based Water Purifiers

According to TechSci research report on “ASEAN Water Purifier Market By Product Type (Under Sink, Counter Top, Faucet Mount & Others {Tankless, Smart Purifiers etc.}), By Sales Channel (Retail, Distributor and Others), By Country (Indonesia, Vietnam, Philippines, Singapore, Myanmar, Cambodia), Competition, Forecast & Opportunities, 2026”, ASEAN water purifier market was valued USD 749.84 Million in 2019 and is expected to grow at CAGR of 9.71% during the forecast period. Rapid urbanization, favourable government regulations for safe and portable water and growing industrial developments is expected to drive growth in ASEAN water purifiers market. Furthermore, rising number of waterborne disease and health disorders due to increasing levels of pollutants in groundwater and rivers, increasing level of contaminants in water such as suspended solids, toxins, harmful gases & chemicals coupled with depleting natural water resources is anticipated to fuel the water purifiers market in the region.

Membrane Based Water Purifiers

Membrane technology for desalination and wastewater treatment has become a promising alternative to many conventionally used techniques, owing to its advantages. Membrane based water purifiers use membrane filters to separate contaminants from water at the ionic level and these are among the fastest growing advanced technologies in the world. While the membrane filter works like other separation processes such as distillation, the main difference is that it does not need any heat source to purify water. Thus, the membrane technology uses less energy than other thermal separation processes. Membrane materials are made up of synthetic polymeric material that react with oxidants used in drinking water treatment. The membranes can be hydrophobic (water repelling) and hydrophilic (water attracting), which describes their ability to resist fouling to some degree.

Some of the other advantages of membrane-based water-purifier technologies include:

· Requires no chemical addition

· Removes contaminations down into the submicron size range

· Backwashing capabilities in many designs

· Continuous operation

· Small carbon footprint

The advancements in membrane production and module design have led to different configurations such as

Micro-Filtration (MF) Water Purifiers

Microfiltration technology utilizes membranes with a pore-size of approximately 0.03-10 microns and operate at relatively low feed water pressure of approximately 100-400 kPa. Microfilters work when contaminants enter the membrane at a higher pressure than the permeate stream. The MF technology is capable of filtering micron-sized toxins such as sand, slit, clays, Giardia Lamblia, cysts, algae, bacteria, yeast cells, smoke particles, suspensions, or gases. Most microfiltration devices are designed as cartridge filters where the entire solution passes through the filter leaving behind particulate matter either inside the filter medium or on the filter surface.

Ultra-Filtration (UF) Water Purifiers

Ultrafiltration technology utilizes membranes with a pore size of approximately 0.002 to 0.1 microns with an operating pressure of 200-700 kPa. The UF membrane work on molecular weight cut-off (MWCO) property, which refers to the maximum molecular weight of dissolved compounds that shall pass through the pores of the membrane. UF membranes are accessible in a wide range of MWCO removal properties, ranging from 1,000 to 100,000 Daltons. The Ultrafiltration technology removes microbiological species as well as some viruses and humic materials. The primary advantages of low-pressure UF membrane technology includes size-exclusion filtration as opposed to media depth filtration, process and plant compactness and simple automation.

Reverse Osmosis (RO) Water Purifiers

Osmosis is a naturally occurring process when two solutions varying in different salinities want to neutralize. Reverse Osmosis technology utilizes pressure to overcome the natural tendency and push water through the semi-permeable membrane by concentrating salts and other dissolved solids on the feed side of the membrane. It is one of the most widely used technologies to generate clean drinking water. RO water purifier technology can be used to remove toxins such as inorganic contaminants, radium, natural organic substances, pesticides, bacteria, and some types of viruses. RO water purifiers are effective with multiple units, but disinfection might be required to ensure the safety of water. Some of the benefits of using RO technology are as follows.

· Results in low effluent concentration

· Removes all contaminant ions and most dissolved non-ions

· Relatively insensitive to flow and total dissolved solids

· Automation makes them simple to operate

· Suitable for small system applications

·Nanofiltration (NF) Water Purifiers

Nanofiltration technology works just like reverse osmosis, but the semi-permeable makes all the difference. The NF water purifiers uses looser semi-permeable membrane, which allows some salts through and rejects larger dissolved molecules such as organics, colour, hardness, etc. Nanofiltration membranes have a pore size of around 0.001 microns and an MWCO of 1,000-100,000 Daltons. The operating pressures are usually near 600 kPa but can operate as high as 1,000 kPa, removing all cysts, bacteria, viruses and humic materials. NF membranes are sometimes called as “softening membranes” as they remove the hardness of the water. However, NF technology requires high energy than MF or UF.

Generally, Microfilter and Ultrafilter membranes are composed from a wide array of materials such as cellulose acetate, polyacrylonitrile, polypropylene, polyvinylidene fluoride, polysulfide, polyether sulfone, or other polymers. Every material has different properties with respect to the surface charge, pH, oxidant tolerance, strength, hydrophobicity, and flexibility. While NF and RO membranes are made from cellulose acetate or polyamide materials, that are susceptible to biodegradation and resistant to continuous low-level oxidants.

According to TechSci research report on “Global Water Purifiers Market By Technology (Membrane, Media & UV), By Region (Asia-Pacific, North America, Europe, Middle East & Africa and South America), Competition, Forecast & Opportunities, 2015 – 2026”, Global water purifiers market valued at USD 41.22 billion in 2019 and is projected to grow at a CAGR of 8.06% during 2020-2026 and reach a market value of USD 68.09 Billion by 2026. The rapid growth can be accounted to rapid industrialization, personal disposable income, and rising awareness about waterborne diseases. Moreover, continuous industrial expansion and unmonitored wastewater discharged into the water resources is deteriorating the quality of water, and leading to health concerns among consumers, which has increased the demand for water purifiers during the forecast period.

Ultraviolet Based Water Purifiers

Ultraviolet water purifiers offer protection against biological contaminants and water-borne viruses, bacteria, moulds, and pathogenic disease-causing microorganisms. Contaminants resistant to chlorine-treated water can also be eliminated with UV water purification treatment. Ultraviolet light emits enough radiation to kill DNA and other microorganisms with an output of around 254 nanometres, radiation of significantly greater intensity than produced by the sun. The UV light source is mounted in front of the flow chamber where water passes and the germicidal radiation present in the water are rendered sterile by the exposure. The UV water purifiers can be used to treat water for various sources including water well, municipal water supply, lake, or spring.

Some of the advantages that UV water purifiers offer are as follows.

· UV water treatment is safer than chlorine treatment as it does not use harmful chemicals or alter the water composition.

· UV light deactivates 99.99% of living organisms present in water and leaves no wastewater or debris to clean out

· UV water purification system saves water as it purifies every drop that enters the water purification system and requires no water to drain.

· UV water purifiers do not add taste or odours.

· The UV filter is easier to maintain as the UV lamp needs to be replaced annually.

· Easy to install and maintain as they do not damage septic tanks or plumbing.

· Media Based Water Purifiers

Some water purifiers consist of a “filter media”, a powdery substance that is personalized to toxins specific to the water source. Filtration media is the workhorse of these water purification systems, getting rid of toxins and impurities when the water passes through the media. Some of the popular mediums in drinking water filtration systems include:

 Activated Carbon

 · Created from organic materials with high carbon content

 · Highly porous surface binds certain toxins and impurities

 · Removes organic contaminants, chlorination by products, lead, copper, and certain pesticides

 · Mitigates unpleasant chlorine taste and odour 

· Catalytic Carbon

       · Made from treating activated carbon to increase its catalytic capabilities

       ·  Used to get rid of chloramine, chemical used in water facilities to disinfect water

       · Does not fall prey to bacteria

 Kinetic Degradation Fluxion (KDF)’

       · Consists of copper and zinc particles

      · Reduces levels of water-soluble heavy metals including chlorine, iron, and hydrogen sulphide

      · Manages scale, bacteria, and algae in water

      · Extremely efficient in removing chlorine

      · Lasts longer and cheaper to operate

Mixed Media

       · Mix of different mediums to remove more impurities and toxins

      · Might include gravel to filter sediments from the water and resin to filter tannins

      · Reduce chloramine levels

Reverse Osmosis Membrane

· Removes a large percentage of impurities from water such as asbestos and hexavalent chromium

· Works by pushing water through a semi-permeable membrane

· Traps water-soluble toxins like heavy metals, organics, bacteria, and pyrogens

· Ultraviolet light

      · UV bulbs produce rays that are fine-tuned to a frequency that best attacks microbes

      · UV rays pierce cell walls, damage contaminants and their DNA

      · Eliminate dangers of bacteria and viruses without tainting water with harsh chemicals

       Activated Aluminium

       ·Activated aluminium removes minerals that cause hard water

       ·Generally found in an ion exchange unit

       · Excellent absorption capacity when compared to other adsorbents like silica gel and molecular adhesives

Conclusion

Rising global population, growing public awareness along with increasing water pollution are increasing reliability of POE water purification system especially in urban areas. Increasing government initiatives to generate awareness about contamination in drinking water is expected to complement the adoption of POE water purifier system.