OxiMax DRDO Iron & Arsenic Removal Systems

Why remove IRON?

• Iron Water readily stains plumbing fixtures, porcelain and cooking utensils.When used in the laundry, it soon stains washables with reddish-brown discolorations. "Iron Water" also leaves its telltale marks on walls and floors if used in doing home cleaning chores. "Iron Water", if not treated, can lead to serious complications in many industrial applications. In fact, there is hardly any wet process work that can be carried on successfully with water that contains iron.

• Iron imparts a disagreeable metallic taste to water. Even when water contains small amounts of iron, a disagreeable, somewhat astringent quality is apparent. Naturally when iron is present in detectable amounts, it can ruin the flavour of tea, coffee and alcoholic beverages. Further iron in the beverages gives them an unappetizing, inky black appearance.

• In its insoluble forms, iron can form deposits in pressure tanks, pipelines,water heaters, commodes and in any other equipment where water is used.

• Desirable limit is 0.3 ppm. Permissible limit is 1.0 ppm.

• Dissolves concentrations of iron in excess of 60 mg/l are known to exist.Usually, however, no more that 5 mg/l of iron are present in supplied water. Unfortunately, iron in water becomes a real source of trouble to the homemaker and industry.

Why remove ARSENIC?

Arsenic contamination of groundwater is a natural occurring high concentration of arsenic in deeper levels of groundwater. It is a high-profile problem due to the use of deep tubewells for water supply in the Ganges Delta, causing serious arsenic poisoning to large numbers of people. A 2007 study found that over 137 million people in more than 70 countries are probably affected by arsenic poisoning of drinking water. Arsenic contamination of ground water is found in many countries throughout the world, including the USA.

Approximately 20 incidents of groundwater arsenic contamination have been reported from all over the world. Of these, four major incidents were in Asia, including locations in Thailand, Taiwan, and Mainland China. In South America, Argentina and Chile are affected. There are also many locations in the United States where the groundwater contains arsenic concentrations in excess of the Environmental Protection Agency standard of 10 parts per billion adopted in 2001. According to a recent film funded by the US Superfund, "In Small Doses"., millions of private wells have unknown arsenic levels, and in some areas of the US, over 20% of wells may contain levels that are not safe.

Health effects of ARSENIC

Main article: arsenic poisoning Consuming water contaminated by arsenic can cause skin and bladder cancer, as well as cardiovascular disease.

Some research concludes that even at the lower concentrations, arsenic contamination is a major causes of death. A study conducted in a contiguous six-county area of southeastern Michigan investigated the relationship between moderate arsenic levels and 23 selected disease outcomes. Disease outcomes included several types of cancer, diseases of the circulatory and respiratory system, diabetes mellitus, and kidney and liver diseases. Elevated mortality rates were observed for all diseases of the circulatory system. The researchers acknowledged a need to replicate their findings.

A preliminary study shows a relationship between arsenic exposure measured in urine and Type II diabetes. The results supported the hypothesis that low levels of exposure to inorganic arsenic in drinking water may play a role in diabetes prevalence.

Arsenic in drinking water may also compromise immune function "Scientists link influenza A (H1N1) susceptibility to common levels of arsenic exposure"..

Contamination specific nations and regions

Bangladesh and West Bengal, India Arsenic contamination of the groundwater in Bangladesh is a serious problem. Prior to the 1970s, Bangladesh had one of the highest infant mortality rates in the world. Ineffective water purification and sewage systems as well as periodic monsoons and flooding exacerbated these problems. As a solution, UNICEF and the World Bank advocated the use of wells to tap into deeper groundwater. Millions of wells were constructed as a result. Because of this action, infant mortality and diarrheal illness were reduced by fifty percent. However, with over 8 million wells constructed, approximately one in five of these wells is now contaminated with arsenic above the government's drinking water standard.

In the Ganges Delta, the affected wells are typically more than 20 m and less than 100 m deep. Groundwater closer to the surface typically has spent a shorter time in the ground, therefore likely absorbing a lower concentration of arsenic; water deeper than 100 m is exposed to much older sediments which have already been depleted of arsenic. The crisis came to international attention in 1995. The study conducted in Bangladesh involved the analysis of thousands of water samples as well as hair, nail, and urine samples. They found 900 villages with arsenic above the government limit.

Criticism has been leveled at the aid agencies, who denied the problem during the 1990s while millions of tube wells were sunk. The aid agencies later hired foreign experts who recommended treatment plants that were inappropriate to the conditions, were regularly breaking down, or were not removing the arsenic.

In West Bengal, India, water is mostly supplied from rivers. Groundwater comes from deep tubewells, which are few in number. Because of the low quantity of deep tubewells, the risk of arsenic patients in West Bengal is comparatively less. According to the World Health Organisation, In Bangladesh, West Bengal (India), and some other areas most drinking-water used to be collected from open dug wells and ponds with little or no arsenic, but with contaminated water transmitting diseases such as diarrhoea, dysentery, typhoid, cholera, and hepatitis. Programmes to provide safe drinking-water over the past 30 years have helped to control these diseases, but in some areas they have had the unexpected side-effect of exposing the population to another health problem arsenic. The acceptable level as defined by WHO for maximum concentrations of arsenic in safe drinking water is 0.01 mg/L. The Bangladesh government's standard is at a slightly higher rate, at 0.05 mg/L being considered safe. WHO has defined the areas under threat: Seven of the nineteen districts of West Bengal have been reported to have ground water arsenic concentrations above 0.05 mg/L. The total population in these seven districts is over 34 million while the number using arsenic-rich water is more than 1 million (above 0.05 mg/L). That number increases to 1.3 million when the concentration is above 0.01 mg/L. According to a British Geological Survey study in 1998 on shallow tube-wells in 61 of the 64 districts in Bangladesh, 46 percent of the samples were above 0.01 mg/L and 27 percent were above 0.050 mg/L. When combined with the estimated 1999 population, it was estimated that the number of people exposed to arsenic concentrations above 0.05 mg/L is 28-35 million and the number of those exposed to more than 0.01 mg/L is 46-57 million (BGS, 2000).

Throughout Bangladesh, as tube wells get tested for concentrations of arsenic, ones which are found to have arsenic concentrations over the amount considered safe are painted red to warn residents that the water is not safe to drink.

One solution is By using surface water and instituting effective withdrawal regulation. West Bengal and Bangladesh are flooded with surface water. We should first regulate proper watershed management. Treat and use available surface water, rain-water, and others. The way we're doing [it] at present is not advisable."

Argentina

The central portion of Argentina is affected by arsenic-contaminated groundwater. Specifically, the La Pampa produces water containing 4-5300 microgram As per litre.

United States

In many locations across the United States the groundwater contains high concentrations of arsenic. Cases of groundwater-caused acute arsenic toxicity, such as those found in Bangladesh, are unknown in the United States where the concern has focused on the role of arsenic as a carcinogen. The problem of high arsenic concentrations has been subject to greater scrutiny in recent years because of changing government standards for arsenic in drinking water. Some locations in the United States, such as Fallon, Nevada, have long been known to have groundwater with relatively high arsenic concentrations (in excess of 0.08 mg/L). Even some surface waters, such as the Verde River in Arizona, sometimes exceed 0.01 mg/L arsenic, especially during low-flow periods when the river flow is dominated by groundwater discharge.

A drinking water standard of 0.05 mg/L (equal to 50 parts per billion, or ppb) arsenic was originally established in the United States by the Public Health Service in 1942. The Environmental Protection Agency (EPA) studied the pros and cons of lowering the arsenic Maximum Contaminant Level (MCL) for years in the late 1980s and 1990s. No action was taken until January 2001, when the Clinton administration in its final weeks promulgated a new standard of 0.01 mg/L (10 ppb) to take effect January 2006.The incoming Bush administration suspended the midnight regulation, but after some months of study, the new EPA administrator Christine Todd Whitman approved the new 10 ppb arsenic standard and its original effective date of January 2006.

Many public water supply systems across the United States obtained their water supply from groundwater that had met the old 50 ppb arsenic standard but exceeded the new 10 ppb MCL. These utilities searched for either an alternative supply or an inexpensive treatment method to remove the arsenic from their water. In Arizona, an estimated 35 percent of water-supply wells were put out of compliance by the new regulation; in California, the percentage was 38 percent .

The proper arsenic MCL continues to be debated. Some have argued that the 10 ppb federal standard is still too high, while others have argued that 10 ppb is needlessly strict. Individual states are able to establish lower arsenic limits; New Jersey has done so, setting a maximum of 0.005 mg/L for arsenic in drinking water. A study of private water wells in the Appalachian mountains found that six percent of the wells had arsenic above the U.S. MCL of 0.010 mg/L.

Nepal

Nepal is subject to a serious problem with arsenic contamination. The problem is most severe in the Terai region, the worst being near Nawalparasi District, where 26 percent of shallow wells failed to meet WHO standard of 10 ppb. A study by Japan International Cooperation Agency and the Environment in the Kathmandu Valley showed that 72% of deep wells failed to meet the WHO standard, and 12% failed to meet the Nepali standard of 50 ppb.



Advantages of DRDO OxiMax Iron removal unit
• Adequate Aeration
• Major portion of iron settles in sedimentation chamber
• Filter bad cracking prevented and clogging delayed
• Double filtration ensures better iron removal
• Efficient backwashing system
• Easy operation and maintenance in rural condition
• Can remove iron up to 40 ppm
• No regeneration required.
• Removes arsenic effectively
• Easily achieves the limit of up to 50 ppb as per requirement of IS:10500-91
• Robust media with high capacity for arsenic removal
• No regeneration required
• Low capital cost
• Negligible operating cost
• Unattended operation

Performance Evaluation