IIT Guwahati researchers develop low-cost system to remove 99 per cent arsenic from groundwater

The Indian Institute of Technology Guwahati researchers have developed a new system that can effectively remove 99 per cent arsenic from contaminated water at a low cost The electrocoagulation system has demonstrated the ability to remove contaminants within a few minutes making it suitable for use in regions with limited access to complex water treatment infrastructureDue to rapid industrialisation and urban growth global reliance on groundwater has increased significantly In many regions groundwater contains arsenic released from natural rock formations or human activities such as mining and agriculture In a press release IIT Guwahati stated that Longterm exposure can cause serious health problems including organ damage and cancerAround 140 million people globally are exposed to unsafe arsenic levels with India Bangladesh and parts of South America among the worst affected To address this many conventional methods have been developed and while some have been successful these are difficult to implement in uncontrolled environments Most methods rely on the addition of chemicals extensive treatment periods and sophisticated equipment Moreover the methods need to be performed on site and have the potential to create surplus sludge increasing the time and energy costs to disposal said in the press release It also stated that electrocoagulation offers a different approach Instead of adding external chemicals it uses an electric current to release metal ions from electrodes immersed in the waterThese ions attach to arsenic and other contaminants allowing them to clump together and be removed from the water through settling or flotation The process is relatively simple to operate and reduces the need for chemical handling Traditional electrocoagulation systems use stationary electrodes which can slow the process and cause deposits to form on the electrode surface over time reducing efficiency To overcome many of the noted system inefficiencies the IIT Guwahati team under the guidance of Prof Mihir Purkait Professor Department of Chemical Engineering IIT Guwahati configured an electrocoagulation system with a rotating anode and a stationary cathode said in the press statementSpeaking on the application of the technology for arsenic mitigation Prof Mihir K Purkait from the Department of Chemical Engineering IIT Guwahati said Electrocoagulation combined with a rotating electrode system offers an efficient solution for arseniccontaminated water In this process a controlled electric current dissolves a sacrificial iron electrode while its rotation enhances mixing and mass transfer leading to uniform generation of iron coagulant species that effectively bind arsenic present in the waterSimultaneously fine gas bubbles formed during the process attach to the arsenicladen flocs and lift them to the surface for easy separation According to Prof Purkait the use of rotating iron electrodes significantly improves removal efficiency while maintaining low operational cost making the technology wellsuited for arsenic removal under optimised conditionsLaboratory tests using both synthetic water and real groundwater samples showed that the system could treat 1 m3 of contaminated water using only approximately 036 units of electricity At prevailing electricity tariffs this translates to a treatment cost of roughly Rs 89 per 1000 litres Under optimised conditions arsenic concentrations were reduced to well below the World Health Organisations guideline of 10 micrograms per litre within two to three minutesThe rotating anode system also produced significantly less sludge than conventional electrocoagulation setups with faster settling and easier handling The EC technology is a costeffective alternative to conventional membrane and adsorption systems particularly for arsenic removal For a small communityscale plant 1050 kilolitres per day an EC system typically costs Rs 815 lakh while a conventional system costs between Rs 1220 lakhAt mediumscale capacities 100500 kilolitres per day the EC system costs Rs 3080 lakh whereas RObased systems often exceed Rs 12 crore Operationally the EC system does not require expensive membranes or frequent chemical dosing and maintenance is largely limited to electrode replacement In contrast membrane systems include high operating costs due to membrane fouling replacement and energyintensive operationsThe developed technology is particularly suitable for rural and semiurban areas where affordability robustness and ease of operation are critical The findings of this study have been published in the prestigious Separation and Purification Technology Journal in a paper coauthored by Prof Mihir Kumar Purkait and his research scholar Mukesh Bharti As the next step the team plans to test the developed system in realfield conditions and evaluate its longterm performance in groundwater containing multiple contaminants such as fluoride and ironThe research team is in discussion with MS Kakati Engineering Pvt Ltd Sivasagar Assam for the fabrication and installation of the system Further commercialisation of the developed technology will be initiated once an appropriate funding source is confirmedThis story has been sourced from a third party syndicated feed agencies Midday accepts no responsibility or liability for its dependability trustworthiness reliability and data of the text Midday managementmiddaycom reserves the sole right to alter delete or remove without notice the content in its absolute discretion for any reason whatsoever