ARSENIC REMOVAL FROM DRINKING WATER
     Ultrafiltration Membrane Assisted Process   

INTRODUCTION

Arsenic (As) is known to be a very toxic element and a carcinogen to human. Even a trace amount of arsenic can be harmful to human health. The World Health Organizations (WHOs) current provisional guideline for arsenic in drinking water is 10 ppb. In India, states like Uttar Pradesh, Bihar, Jharkhnad, West Bengal, Assam, Manipur, mainly in Ganga-Meghna-Brahmaputra (GMB) plain covering an area of about 569749 sq km with a population of over 500 million have reported serious illnesses due to presence of arsenic.

The arsenic removal from drinking water by physicochemical process provides process for decontamination of water with respect to arsenic. BARC developed know how of ultrafiltration (UF) based membrane technology for water decontamination with respect to microbiological contamination at both domestic and community scale is available for transfer separately. The present technology is a novel Ultrafiltration (UF) membrane assisted physicochemical process for removal of arsenic from ground/surface water to make the water safe for drinking.

Salient features
• Simple and rapid
• Adoptable at both domestic and community level
• Capability of high decontamination - Product water not only free from arsenic but also free from secondary contaminants like iron,
    manganese and microorganisms.
• Can operate without electricity
• No specific requirement for waste disposal
• Cost effective

Applications 
• Removal of arsenic from ground/surface water to provide safe drinking water free from primary contaminant like arsenic as well as
    secondary contaminants like iron and microorganisms.
• Technology can be adopted at both domestic and community level

Process
UF membrane assisted physicochemical process/device is capable of removing arsenic contamination from ground/surface water for drinking purposes from a feed concentration of 500 ppb or more to less than 10 ppb (which is the desirable limit set by BIS). The entire process involves two steps: 1) Sorption of arsenic species on the in situ generated sorbent by simple addition of two reagents. 2) Filtration of arsenic containing sludge using UF membrane device based on the technology developed by BARC. The two reagents required for the first step are to be prepared using the procedure given in the technology transfer document. The details of the device required for the second step is available in the form of technology with BARC and can be taken separately. These devices are also available with several licensees of BARC in the form of commercial products.

Raw Materials
All the raw materials required for preparing the reagents for removal of arsenic are available in the local market.

Infrastructure
The development of arsenic removal kit requires a small laboratory with few common equipments like weighing balances, exhaust and common glasswares.

Manpower
One Chemist and one skilled worker would be adequate for the purpose.

Cost Aspects
The cost of raw materials for preparation of reagents sufficient to treat 1000 liters of arsenic contaminated water (contamination level: 500 ppb) is approximately Rs. 8 /- . The cost of UF membrane device required for filtration will depend if the filtration unit is directly purchased from the market or the service provider is manufacturing it by becoming of licensee of BARC.