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Background: Punjab is becoming cancer capital of India due to increasing cancer rates especially in Malwa belt. Keeping in view the alarming increase in cancer incidence in this region, 1881 Reverse Osmosis plants have been installed in 16 districts of Punjab by the Government since 2010, but People are not utilizing this community RO water fully. Although 180 crores of rupees have been spent on installation of these RO plants by the government, but little attempts have been made to ascertain the extent of utilization of this water by the people and the Knowledge, Attitude and practices of the people residing in rural areas regarding community RO water. Aim of the study to assess the utilization and awareness of community RO water by the households in the study area. Results: There is only 50% utilization of community RO water as per this study. Most common responses elicited for not using community RO water was the unavailability of any family member for fetching this water (32%). Some other reasons observed were affordability (18%), accessibility due to distance of RO plant (15%) and dislike for taste of water (17%) though most of the households were aware of the risks of using contaminated water. Conclusions: though utilization of community RO water has increased as compared to past records still it is not as much as expected, since it has been 5 years since the installation of RO plants. Government heads to intensify its efforts in making people aware and solving the problems encountered in using community RO water. [ABSTRACT FROM AUTHOR]

Besides water supply, there are serious concerns regarding the safety and availability of drinking water. Even the quality of drinking water in India is also a major concern. Water quality is affected by both point and non-point sources of pollution. There are various methods adopted to purify water. A major concern raised in this paper is about reverse osmosis-based technology presumably being marketed aggressively. This technology has been criticized for its harmful effects which relate to demineralization of water. Using different evidences we have explored arguments both in favour and against this technology. However, evidence based on current status of Indian data remains inconclusive. [ABSTRACT FROM AUTHOR]

Arsenic contamination of groundwater is posing a serious challenge to drinking water supplies on a global scale. In India and Bangladesh, arsenic has caused the most serious public health issue in the world for nearly two decades. The aim of this work was to study an arsenic removal system based on reverse osmosis at pilot scale treating two different water sources from two different locations in the State of Bihar, India. For this purpose two villages, Bind Toli and Ramnagar in the Patna District were selected, both located very close to the river Ganga. The trials were conducted with aerated and non-aerated groundwater. It is the first time that the arsenic removal efficiency for aerated and non-aerated groundwater by reverse osmosis technology in combination with an energy-saving recovery system have been studied. As the principle of reverse osmosis requires a relatively high pressure, its energy demand is naturally high. By using an energy recovery system, this demand can be lowered, leading to an energy demand per liter permeate of 3–4 Wh/L only. Due to high iron levels in the groundwater and as a consequence the precipitation of ferric (hydr)oxides, it was necessary to develop a granular media filter for the trials under aeration in order to protect the membrane from clogging. Two different materials, first locally available sand, and second commercially available anthracite were tested in the granular media filter. For the trials with aerated groundwater, total arsenic removal efficiency at both locations was around 99% and the arsenic concentration in permeate was in compliance with the WHO and National Indian Standard of 10 μg/L. However, trials under anoxic conditions with non-aerated groundwater could not comply with this standard. Additionally a possible safe discharge of the reverse osmosis concentrate into an abandoned well was studied. It was observed that re-injection of reject water underground may offer a safe disposal option. However, long-term hydrogeological studies need to be conducted for confirmation. [ABSTRACT FROM AUTHOR]

Sea-water desalination has emerged as the key alternative to overcome demand–supply gap of potable water, worldwide. This paper aims to carry out a technology review of sea-water desalination, technologies in an integrated framework of economic, environmental and ecological analyses. The economic analysis here refers to a project/technology development effort analysis in the context of national economy. The cost per unit output from this perspective is the economic cost. In an environmental analysis, the higher specific energy consumption in a process vis-à-vis the best technology option in the project area is measured in terms of certified emission reduction. In ecosystem analysis, the accent is to find out whether the technology disrupts the existing eco-system. Such a disturbance entails a huge ecological cost. The cost quantified per unit output is arrived at as the reduction in GDP in the project affected area due to the direct and indirect effects of adverse ecological effects; these effects are deduced using specifically developed I–O tables 'with and without' technology options, for the project area. The choice of technology is the one with the minimum composite cost per unit output. The composite cost in the context is the sum of economic cost, the environmental cost and the ecological cost per unit output. The framework is applied in the technology review of low-temperature thermal desalination process and its impact on project areas of Lakshadweep islands and Thoothukodi district vis-à-vis the alternative RO process of sea-water desalination technology. [ABSTRACT FROM AUTHOR]

Abstract: Thin film composite (TFC) reverse osmosis membrane containing polyamide active layer on porous polysulfone support was developed at the scale of 1m width×100m long in a batch using semi-automated mechanical casting and coating machines. The polysulfone support was made according to phase inversion method at the rate of 3−6m/min., and the polyamide active layer on the polysulfone support was prepared by interfacial polymerization method at the rate of 0.3−0.5m/min under different conditions. Since desalination of brackish water does not require the membrane with very high salt rejection efficiency, emphasis was placed on increase in the flux while maintaining the salt rejection at 94±2%. The membrane preparation conditions and structure−performance relationships were correlated by different techniques like porometry, infrared spectra, scanning electron microscopy and atomic force microscopy. The TFC membranes exhibited 94−96% salt rejection with water flux of 50−65L/m2.h when tested with 5000−1500ppm salt solution at 250psi. Surface modification of the TFC membrane with polymers containing hydrophilic groups was carried out to impart fouling resistance. Spiral modules of 4040 and 8040 size were made and tested them extensively in the field conditions in 500−2000 LPH brackish and sea water desalination plants. [Copyright &y& Elsevier]

Abstract: The work was motivated by the increasing awareness of the need for enhancing water supplies schemes in arid lands featuring an appropriate technology for solar energy use in the desalination field in India. The fresh water crisis is already evident in many parts of India, varying in scale and intensity at different times of the year. India''s rapidly rising population and changing lifestyles also increases the need for fresh water. Fresh water is increasingly taking centre stage on the economic and political agenda, as more and more disputes between and within states, districts, regions, and even at the community level arises. The conventional desalination technologies like multi stage flash, multiple effect, vapor compression, iron exchange, reverse osmosis, electro dialysis are expensive for the production of small amount of fresh water, also use of conventional energy sources has a negative impact on the environment. Solar distillation represents a most attractive and simple technique among other distillation processes, and it is especially suited to small-scale units at locations where solar energy is considerable. India, being a tropical country is blessed with plenty of sunshine. The average daily solar radiation varies between 4 and 7kWh per square meter for different parts of the country. There are on an average 250–300 clear sunny days in a year, thus it receives about 5000 trillion kWh of solar energy in a year. In spite of the limitations of being a dilute source and intermittent in nature, solar energy has the potential for meeting and supplementing various energy requirements. Solar energy systems being modular in nature could be installed in any capacity as per the requirement. This paper consists of an overall review and technical assessments of various passive and active solar distillation developments in India. This review also recommended some research areas in this field leading to high efficiency are highlighted. [Copyright &y& Elsevier]

Abstract: Arsenic poisoning in drinking water is a health issue in many Asian countries including Bangladesh, India, China and Vietnam. In areas where the drinking water supply contains unsafe levels of arsenic, technologies to remove arsenic are of prime importance. Many technologies have been developed for the removal of arsenic. Among those reverse osmosis (RO) and nanofiltration (NF) are very promising techniques because they have the advantage of removing dissolved arsenic along with other dissolved and particulate compounds. So far, however, this kind of membrane filtration has needed bulky and sophisticated units, which are not suitable for application in the rural areas of developing and newly industrializing countries. Therefore the purpose of this work was to test a small-scale, commercially available marine RO desalinator with three different membrane modules on arsenic removal. The experiments were conducted with arsenic-spiked local tap water, using As(III) and As(V) up to feed concentrations of 2400 μg/L. The As(V) rejection was generally much better than the retention of As(III). With two of the tested membranes As(V) rejection was so high, that the permeate water quality complied with the WHO recommended maximum contaminant level (MCL) of 10 μg/L even at a feed concentration of 2400 mg/L. In the case of As(III) only feed concentrations below 350 μg/L resulted in permeate concentration lower than the MCL. The experiments should provide a basis for field tests on the ground in Bangladesh using natural arsenic contaminated groundwater. These field tests are currently running. [Copyright &y& Elsevier]