Academia.edu no longer supports Internet Explorer.
To browse Academia.edu and the wider internet faster and more securely, please take a few seconds to upgrade your browser.
Papers by Pravin Nemade
Journal of Hazardous Materials, 2009
Journal of Chemical Technology and Biotechnology, 2010
BACKGROUND: The constructed soil filter (CSF), also known as soil biotechnology is a system for w... more BACKGROUND: The constructed soil filter (CSF), also known as soil biotechnology is a system for water renovation, which makes use of formulated media, culture of soil micro- and macro-organisms, additives and plantation to purify water and wastewater. The process gives benefits in terms of applicability across very small to large scale, natural aeration, absence of moving parts, no biological sludge generation, odor free green aesthetic ambience.RESULTS: Residence time distribution (RTD) studies were carried out using laboratory scale CSF. Pulse potassium bromide tracer tests were carried out to determine RTD, and the Peclet number found to be 9–13 for a 2 m bed, and 2–3 for a 0.30 m bed with oxygen transfer of 0.08 h−1.CONCLUSION: The two-channel dispersion model for flow behavior shows a good fit to the experimental data, indicating a reactor Peclet number 9–13 for a 2 m bed and 2–3 for a 0.3m bed. Oxygen transfer studies carried out using various methods gave an oxygen transfer coefficient of about 0.08 h−1. Wastewater purification studies indicate overall COD removal rate of around 50 mg L−1 h−1, suggesting that highly aerobic conditions are prevalent in the CSF system. Copyright © 2009 Society of Chemical Industry
Ecological Engineering, 2009
Ecological Engineering, 2009
Ecological Engineering, 2008
Asia-pacific Journal of Chemical Engineering, 2008
Arsenic poisoning is a global problem. It is known that groundwater in Bangladesh and West Bengal... more Arsenic poisoning is a global problem. It is known that groundwater in Bangladesh and West Bengal predominantly contains As(III) and concentrations of Fe(II) which are often too low for removal of arsenic in optimum quantities. To eliminate arsenic from drinking water, several basic methods such as coagulation, adsorption, ion exchange, filtration, membrane processes, are reported. To deal with this issue on a small to large scale, we present a novel approach to remove arsenic and iron from water by constructed soil filter (CSF).In CSF, As (III) is oxidized to As(V) by media via natural oxidation and subsequently, arsenic is co-precipitated with iron. Here water containing arsenic, iron, and phosphate is passed through the CSF media at the rate of 100 ml/min. Results show a mean residence time of 8.6 min and a holdup of 1.85 l. Results of six runs show that with initial As(III) of 300 µg/l and iron concentration of 5–10 mg/l, residual arsenic levels below 10 ppb and residual iron < 0.30 mg/l in water can be achieved.In CSF, no chemicals are needed for the oxidation of As(III) to As(V). The oxidation takes place due to the presence of various oxides such as iron, manganese, aluminum, and the microbial diversity in the media of soil bioreactor. Such a novel technology is also applied for purification of water and wastewater. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd.
Journal of Hazardous Materials, 2009
Journal of Chemical Technology and Biotechnology, 2010
BACKGROUND: The constructed soil filter (CSF), also known as soil biotechnology is a system for w... more BACKGROUND: The constructed soil filter (CSF), also known as soil biotechnology is a system for water renovation, which makes use of formulated media, culture of soil micro- and macro-organisms, additives and plantation to purify water and wastewater. The process gives benefits in terms of applicability across very small to large scale, natural aeration, absence of moving parts, no biological sludge generation, odor free green aesthetic ambience.RESULTS: Residence time distribution (RTD) studies were carried out using laboratory scale CSF. Pulse potassium bromide tracer tests were carried out to determine RTD, and the Peclet number found to be 9–13 for a 2 m bed, and 2–3 for a 0.30 m bed with oxygen transfer of 0.08 h−1.CONCLUSION: The two-channel dispersion model for flow behavior shows a good fit to the experimental data, indicating a reactor Peclet number 9–13 for a 2 m bed and 2–3 for a 0.3m bed. Oxygen transfer studies carried out using various methods gave an oxygen transfer coefficient of about 0.08 h−1. Wastewater purification studies indicate overall COD removal rate of around 50 mg L−1 h−1, suggesting that highly aerobic conditions are prevalent in the CSF system. Copyright © 2009 Society of Chemical Industry
Ecological Engineering, 2009
Ecological Engineering, 2009
Ecological Engineering, 2008
Asia-pacific Journal of Chemical Engineering, 2008
Arsenic poisoning is a global problem. It is known that groundwater in Bangladesh and West Bengal... more Arsenic poisoning is a global problem. It is known that groundwater in Bangladesh and West Bengal predominantly contains As(III) and concentrations of Fe(II) which are often too low for removal of arsenic in optimum quantities. To eliminate arsenic from drinking water, several basic methods such as coagulation, adsorption, ion exchange, filtration, membrane processes, are reported. To deal with this issue on a small to large scale, we present a novel approach to remove arsenic and iron from water by constructed soil filter (CSF).In CSF, As (III) is oxidized to As(V) by media via natural oxidation and subsequently, arsenic is co-precipitated with iron. Here water containing arsenic, iron, and phosphate is passed through the CSF media at the rate of 100 ml/min. Results show a mean residence time of 8.6 min and a holdup of 1.85 l. Results of six runs show that with initial As(III) of 300 µg/l and iron concentration of 5–10 mg/l, residual arsenic levels below 10 ppb and residual iron < 0.30 mg/l in water can be achieved.In CSF, no chemicals are needed for the oxidation of As(III) to As(V). The oxidation takes place due to the presence of various oxides such as iron, manganese, aluminum, and the microbial diversity in the media of soil bioreactor. Such a novel technology is also applied for purification of water and wastewater. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd.
Uploads
Papers by Pravin Nemade