Touching upon the various technologies and products that are available in the market is Daya Kingston, who tells us why India's water treatment industry is overflowing with potential.To say water is a concern in our country would be putting it rather mildly. Every Indian - urban or rural - is aware of the paucity of domestic water. The situation on the industrial front is equally dire; a recent government assessment predicts that the water requirement for industrial use will increase from the current 30 billion cu m to 120 billion cu m by 2025. In this scenario, measures like rainwater harvesting, desalination and wastewater treatment are the need of the hour.Avenues of hopeFamously espoused by none other than former president APJ Abdul Kalam, who used the technique to great effect in Rashtrapati Bhavan - rainwater harvesting is slowly catching on across the country. This essentially involves channelling rainwater from a roof into storage via an arrangement of gutters and pipes. Another option is desalination, which requires major capital investment. The true potential of desalination projects has not yet been fully explored in India. In the coming years, plants are likely to involve private-sector participation as most new coastal power plants that require desalination are private entities. On the municipal front, build, operate, own and transfer (BOOT) schemes will continue. A third avenue is water and wastewater treatment, which incorporates the buzz words of today: recycle and reuse. Indeed, India's burgeoning water and wastewater treatment market is estimated at about $420 million today with a healthy growth of 18 per cent.The expert viewThese avenues are the only sustainable way ahead, agree industry experts. "One way to resolve the issue is for urban governing bodies and councils to strictly implement decentralised treatment and recycling, whereby wastewater is treated close to where it is generated or at the point of generation and discharge, and then reused," says Harshad Bastikar, CEO, Jaldhara Technologies. This would be ideal for all urban areas. Wastewater treatment has been a challenge owing to varying influent characteristics and stringent effluent regulations. This becomes further complex because of the inability and mishandling of variable and erratic flows, operational inadequacies, space constraints and treatment efficiencies. Therefore, technologies must be focused on wastewater recycle and reuse with higher productive efficiency and low treatment cost on a per mld or per cubic metre of flow. There is an immediate need for low-cost, high-treatment-efficiency compact solutions."Offering his perspective, Ankur Parikh, Director-Industrial, Alfaa UV, says, "The quality of water service and sanitation services need to improve. Water reuse will become important and unavoidable owing to our fast growing population and climate change. Water stress will only increase as we become more industrialised. As a result, the need for effective and reliable disinfection and contaminant treatment systems is set to grow, and the industry will definitely receive a lot of attention in the coming future."The treatmentThis, then begs the question: how does the treatment process work? Well, wastewater is usually treated with a combination of physical, chemical and biological processes and operations. These work at various levels to remove solids, organic matter and nutrients from wastewater. The various levels include preliminary, primary, secondary, and tertiary and/or advanced wastewater treatment. Preliminary treatment is the basic step where coarse solids and other large materials in raw wastewater are removed through coarse screening, grit removal and comminution of large objects.Primary wastewater treatment: This consists of removing settleable organic and inorganic solids by sedimentation and the removal of materials that will float (scum) by skimming. Primary sedimentation tanks or clarifiers may be round or rectangular basins, typically 3-5 m deep, where the water is allowed to stay till the sludge settles and is moved to sludge processing units. In large sewage treatment units, this process is carried out through biological processing or anaerobic digestion.Secondary wastewater treatment: This is the next stage to further treat the effluent from primary treatment to remove residual organics and suspended solids. Usually, this involves the removal of biodegradable dissolved and colloidal organic matter using aerobic biological treatment processes. This consists of activated sludge processes, trickling filters or bio-filters, oxidation ditches, and rotating biological contactors (RBC).Advanced wastewater treatment: Tertiary or advanced wastewater treatment is used for the removal of specific wastewater constituents that cannot be removed by secondary treatment. An activated sludge process is used to achieve this. Disinfection is used in certain instances and normally involves the injection of a chlorine solution at the head end of a chlorine contact basin.The industryDespite the immense potential, the Indian water and wastewater treatment market is highly fragmented and unorganised. Geographically, it is concentrated in Mumbai, Pune, Chennai, Hyderabad, New Delhi, Kolkata and Ahmedabad. You can actually split the market into three major segments: large players like VA Tech Wabag, Degremont, Hindustan Dorr-Oliver, Paramount, Ion Exchange, Thermax, and so on; medium-sized players like Doshion, Aquatech, Fontus Water, Driplex, TEAM and Ions Hydro; and small players that number over 500.Although the market is extremely competitive, it will continue to remain dynamic, allowing players who offer new technology and specific applications to carve a niche for themselves.The evolution of technologyInitially, wastewater was treated by demineralisation. However, technology has brought in a sea change and a shift to reverse osmosis (RO) treatment and the emergence of newer technologies like ultrafiltration, UV and electrodialysis. Different companies have evolved their unique formats of these technologies.The Grewa rangeAs Bastikar tells us, "We have launched a new generation of products under the brand name Greywater; the entire Grewa product range is purpose-built and follows a 'no waste' philosophy." All the products are completely containerised, have the smallest footprint, operate at very low lifecycle costs, perform to high efficiency, are fully automatic, and use no chlorine or hazardous chemicals. They can be remotely monitored or controlled, if required. They are applied at various points of entry and discharge areas such as residential buildings, hotels, resorts, commercial facilities, IT parks, hospitals and various industries.The company's wastewater/sewage /effluent treatment products comprise Grewa-R: Sequential Biological Reactor (SBR); Grewa-M: Submerged Membrane Biological Reactor (MBR); and Grewa-Fleet: Specialised Effluent Treatment (ETP). And its water treatment products comprise Grewa-U: Ultra Filtration (UF) and Grewa-O: Reverse Osmosis (RO). They also have add-on modules like Grewa-T, Grewa-S, Grewa-F and Grewa-C. "All Grewa products work on a process that is fully automatic, simple to operate and based on timing," adds Bastikar. "These systems respond to flow and load variations automatically, which is why they can be very easily expanded and scaled up, as and when required. Treatment processes, including liquid and solid separation, are done automatically and continuously in a single tank that saves immensely on the footprint area. Additionally, the absence of odour and gas emissions makes our products conducive to any residential or inhabited environment."With individual unit capacities ranging between 2 cu m per day for standalone villas or bungalows to 300 cu m per day in standard product form, all plants are modular and can be combined easily for increased capacity, Bastikar informs. The range includes both biological and separation technology based products, ready to use and fully automated. These products offer low lifecycle operating costs with the least power consumption and use no hazardous chemicals. Jaldhara Technologies is headquartered in Mumbai and manufactures its products in Vapi.The Zero Liquid Discharge SystemThanks to its Zero Liquid Discharge (ZLD) System, the list of accolades for Chennai-based Aqua Designs India Ltd is extensive, including 'Commendable Water Company of 2010-2011', 'Distinguished Water Efficient Project of 2010-2011' and 'Distinguished Water Reuse Project of 2010-2011', amongst others. "ZLD provides an economical solution to all industries that have to compete with local water availability, water costs and wastewater discharge criteria," explains S Suthakar, Managing Director, Aqua Designs India Ltd. "It combines a number of wastewater treatment technologies, including sanitary collection, biological water treatment, microfiltration membrane softening, RO water recycling and evaporation ponds. These systems recycle waste streams such as boiler blow down, cooling tower blow down, RO reject, DM regeneration waste, softener regeneration waste, filter backwash and plant drains."This is a fully integrated automated system incorporating a mechanical evaporator and solid dewatering. Up to 95 to 99 per cent of wastewater can be recovered as high-purity distillate (<10 mg/I TDS), which can be used for cooling towers or boiler makeup water. Notably, ZLD reduces water supply costs given that industries no longer need to purchase as much fresh water for manufacturing. "We provide design-reliable, cost-effective systems with benefits like energy efficiency, ease of operation and maximum recycle," adds Suthakar.UV technologyThe search for environment-friendly technology has led to the increased use of UV treatment of wastewater. "UV technology has always been considered environment-friendly, relative to other disinfection technologies," says Parikh. "It doesn't use any chemicals and poses no issues of disinfection by-products, many of which have been proven to be carcinogenic. We are focusing on making systems even more efficient and cutting down on the amount of power used to operate these plants."As he explains, water-borne contamination is a major problem in India and around the world. Effective disinfection is essential before the water is distributed to individual homes and buildings. "Worldwide, the trend is to upgrade plants using chlorination technology and replace them with more environment-friendly and safe UV systems," adds Parikh. "As many of India's drinking water plants do not even have effective chlorination systems in place, it is in the unique position where it can completely leapfrog this outdated technology and directly adopt UV. UV is currently the best technology in the world for safeguarding drinking water from harmful microorganisms, including Cryptosporidium and Giardia."The challenge aheadEvidently, the market is in place, as are the players, to explore sustainable avenues of water reuse, recycle and conservation. But, sterner measures will be required going forward. For instance, when it comes to regulating wastewater, regulatory bodies appear to lack the power to enforce many of the guidelines and the mandatory requrement of a functional treatment plant. The government must immediately implement various incentives for 'recycled water intake per unit of production' in the industry and 'recycled water reuse' in urban areas. Wastewater management must also address the rural context through sound and integrated ecosystem-based management. Only then can we, so to speak, stem the tide.