Abhisek Roy - Academia.edu (original) (raw)

Papers by Abhisek Roy

Research paper thumbnail of Assessment and development of air quality forecasting models by the combination of PCA and ANN at metropolis Kolkata, India

Research Journal of Chemistry and Environment, 2021

PM10, PM2.5, SO2, NO2, Pb, As and Ni were monitored at Jadavpur, Kolkata over the time span of Oc... more PM10, PM2.5, SO2, NO2, Pb, As and Ni were monitored at Jadavpur, Kolkata over the time span of October 2016 to March 2017. The air quality of the study area was assessed in terms of air quality index (AQI) which is calculated on the assessed concentration of the pollutants. The result of the study showed significant seasonal variance and the ambient air of the study area is highly polluted in terms of particulate matters, NO2 and metallic pollutants. AQI study reveals that PM2.5 was found responsible for this degraded air quality of Kolkata. Principal component analysis (PCA) was used to identify possible contributors i.e. i) construction work, windblown dust, road dust and earth crust (variance- 28.98%); ii) automobile exhaust (variance- 20.47%); iii) brake wear source, road dust and tire wear (variance- 18.07%) of air pollution in the study area. Multiple linear regression (MLR) and feedforward backpropagation artificial neural network (FFBPANN) were used in combination with PCA t...

Research paper thumbnail of Sustainable Management of Arsenic-Bearing Sludge

Waste Management and Resource Efficiency, 2018

Electrochemical Arsenic Remediation (ECAR) technology has been developed to efficiently reduce hi... more Electrochemical Arsenic Remediation (ECAR) technology has been developed to efficiently reduce high levels of arsenic in groundwater below the WHO MCL at extremely low cost. This process produces arsenic-bearing sludge which being a hazardous waste has to be disposed by a cost-effective robust stabilization process. This study is focused on the embedment of ECAR sludge in concrete in variable proportion (% by weight of cement) up to the point of substantial deterioration in strength in an environmentally sound manner. This sludge differs reasonably from that of silt and sand in terms of parameters, viz. specific gravity, optimum moisture content, void ratio, and porosity. Grain size is similar to filler materials used in concrete, which suggests that there is potential for the sludge to be embedded in concrete, thus emphasizing its immobilization. The sludge was added by replacing equivalent amount of sand and extra water equivalent to the OMC of the sludge in the concrete mix. Seve...

Research paper thumbnail of COVID-19 Lockdown: Lessons learnt using multiple air quality monitoring station data from Kolkata City in India

On March 16, 2020, Kolkata, a megacity located in the eastern part of India announced partial loc... more On March 16, 2020, Kolkata, a megacity located in the eastern part of India announced partial lockdown due to COVID-19 crisis ahead of the India-wide lockdown pronouncement with effect from March 25, 2020. This study presents an analysis for multiple pollutants with special focus on NO2 and O3, based on data from different monitoring stations located across Kolkata city, for the period of 16 March- 17 May 2020. A comparison was done with the pre-lockdown period of 1st February – 15th March 2020. Most significant reduction was observed in the concentration of nitrogen dioxide (NO2) (- 76.8%), volatile organic compounds (VOCs) (- 69.5%), PM10 (- 64.6%) and PM2.5 (- 60.9%). A lower percentage reduction was found for CO, sulfur dioxide (SO2) and ammonia (- 48.6%, - 41.7% and – 41.1% respectively). However, during partial lockdown, Lockdown Phase-1, Phase -2, and Phase -3 surface-level ozone (O3) has changed respectively by 31.72%, 31.13%, -14.28% and -14.05% ; which resulted in an overa...

Research paper thumbnail of Long-term electrode behavior during treatment of arsenic contaminated groundwater by a pilot-scale iron electrocoagulation system

Research paper thumbnail of Degradation of Air Quality (PM10) with Seasonal Change and Health Risk Assessment in Metro City Kolkata

International Journal of Advancement in Life Sciences Research, 2020

Research paper thumbnail of Strategies for successful field deployment in a resource-poor region: Arsenic remediation technology for drinking water

Development Engineering, 2019

Research paper thumbnail of Concrete stabilization of arsenic-bearing iron sludge generated from an electrochemical arsenic remediation plant

Journal of Environmental Management, 2019

Research paper thumbnail of Leachate and Septage Management of Model Regional Waste Management Centre of Six Waste Bank Municipalities of River Hooghly

Waste Management and Resource Efficiency, 2018

The Kolkata Solid Waste Management Improvement Project (KSWMIP) proposes an integrated municipal ... more The Kolkata Solid Waste Management Improvement Project (KSWMIP) proposes an integrated municipal solid waste management system for six waste bank municipalities of river Hoogly, namely Champdani, Baidyabati, Serampore, Rishra, Konnagar and Uttarpara-Kotrung, which is being executed by the Kolkata Metropolitan Development Authority (KMDA) in association with the six municipalities under funding support from the Japanese International Cooperation Agency (JICA). Segregated waste from two bin system will be transported to transfer stations of the municipalities. Recyclables will be taken out for reuse, and biodegradable portion will be composted by windrow process. Inerts and rejects (60% of the total) will be transported to Regional Waste Management Centre (RWMC) for sanitary landfilling along with 50 m3/day of septic tank sludge (septage). Aim of this work is to manage leachate and septage in RWMC which consists of sanitary landfill (SLF) of 140,000 m3 capacity, approximate life of 16 years; septage treatment facility of capacity 125 m3/day with dilution water and leachate treatment facility of capacity 816 m3/day. Septage will be treated by the single-stage anaerobic sludge digester with 40 days detention period, and digested sludge will be sent to Centrifuge for dewatering. Supernatant liquor from anaerobic sludge digester (75.37 m3/day) and centrate from centrifuge (40.6 m3/day) will be discharged to the leachate treatment system for further treatment. Mixture of treated septage (116 m3/day) and leachate (700 m3/day) will be treated first in the facultative aerated lagoon-I, then in the facultative aerated lagoon-II in series. Treated effluent from the facultative aerated lagoon II will be transferred by gravity to the facultative cum sedimentation pond for further treatment. Treated effluent will be discharged in the Dankuni Canal by gravity after meeting the discharge standards of inland surface water, and a part of it will be used as dilution water in the septage treatment system and also for other uses within the RWMC.

Research paper thumbnail of Assessment and development of air quality forecasting models by the combination of PCA and ANN at metropolis Kolkata, India

Research Journal of Chemistry and Environment, 2021

PM10, PM2.5, SO2, NO2, Pb, As and Ni were monitored at Jadavpur, Kolkata over the time span of Oc... more PM10, PM2.5, SO2, NO2, Pb, As and Ni were monitored at Jadavpur, Kolkata over the time span of October 2016 to March 2017. The air quality of the study area was assessed in terms of air quality index (AQI) which is calculated on the assessed concentration of the pollutants. The result of the study showed significant seasonal variance and the ambient air of the study area is highly polluted in terms of particulate matters, NO2 and metallic pollutants. AQI study reveals that PM2.5 was found responsible for this degraded air quality of Kolkata. Principal component analysis (PCA) was used to identify possible contributors i.e. i) construction work, windblown dust, road dust and earth crust (variance- 28.98%); ii) automobile exhaust (variance- 20.47%); iii) brake wear source, road dust and tire wear (variance- 18.07%) of air pollution in the study area. Multiple linear regression (MLR) and feedforward backpropagation artificial neural network (FFBPANN) were used in combination with PCA t...

Research paper thumbnail of Sustainable Management of Arsenic-Bearing Sludge

Waste Management and Resource Efficiency, 2018

Electrochemical Arsenic Remediation (ECAR) technology has been developed to efficiently reduce hi... more Electrochemical Arsenic Remediation (ECAR) technology has been developed to efficiently reduce high levels of arsenic in groundwater below the WHO MCL at extremely low cost. This process produces arsenic-bearing sludge which being a hazardous waste has to be disposed by a cost-effective robust stabilization process. This study is focused on the embedment of ECAR sludge in concrete in variable proportion (% by weight of cement) up to the point of substantial deterioration in strength in an environmentally sound manner. This sludge differs reasonably from that of silt and sand in terms of parameters, viz. specific gravity, optimum moisture content, void ratio, and porosity. Grain size is similar to filler materials used in concrete, which suggests that there is potential for the sludge to be embedded in concrete, thus emphasizing its immobilization. The sludge was added by replacing equivalent amount of sand and extra water equivalent to the OMC of the sludge in the concrete mix. Seve...

Research paper thumbnail of COVID-19 Lockdown: Lessons learnt using multiple air quality monitoring station data from Kolkata City in India

On March 16, 2020, Kolkata, a megacity located in the eastern part of India announced partial loc... more On March 16, 2020, Kolkata, a megacity located in the eastern part of India announced partial lockdown due to COVID-19 crisis ahead of the India-wide lockdown pronouncement with effect from March 25, 2020. This study presents an analysis for multiple pollutants with special focus on NO2 and O3, based on data from different monitoring stations located across Kolkata city, for the period of 16 March- 17 May 2020. A comparison was done with the pre-lockdown period of 1st February – 15th March 2020. Most significant reduction was observed in the concentration of nitrogen dioxide (NO2) (- 76.8%), volatile organic compounds (VOCs) (- 69.5%), PM10 (- 64.6%) and PM2.5 (- 60.9%). A lower percentage reduction was found for CO, sulfur dioxide (SO2) and ammonia (- 48.6%, - 41.7% and – 41.1% respectively). However, during partial lockdown, Lockdown Phase-1, Phase -2, and Phase -3 surface-level ozone (O3) has changed respectively by 31.72%, 31.13%, -14.28% and -14.05% ; which resulted in an overa...

Research paper thumbnail of Long-term electrode behavior during treatment of arsenic contaminated groundwater by a pilot-scale iron electrocoagulation system

Research paper thumbnail of Degradation of Air Quality (PM10) with Seasonal Change and Health Risk Assessment in Metro City Kolkata

International Journal of Advancement in Life Sciences Research, 2020

Research paper thumbnail of Strategies for successful field deployment in a resource-poor region: Arsenic remediation technology for drinking water

Development Engineering, 2019

Research paper thumbnail of Concrete stabilization of arsenic-bearing iron sludge generated from an electrochemical arsenic remediation plant

Journal of Environmental Management, 2019

Research paper thumbnail of Leachate and Septage Management of Model Regional Waste Management Centre of Six Waste Bank Municipalities of River Hooghly

Waste Management and Resource Efficiency, 2018

The Kolkata Solid Waste Management Improvement Project (KSWMIP) proposes an integrated municipal ... more The Kolkata Solid Waste Management Improvement Project (KSWMIP) proposes an integrated municipal solid waste management system for six waste bank municipalities of river Hoogly, namely Champdani, Baidyabati, Serampore, Rishra, Konnagar and Uttarpara-Kotrung, which is being executed by the Kolkata Metropolitan Development Authority (KMDA) in association with the six municipalities under funding support from the Japanese International Cooperation Agency (JICA). Segregated waste from two bin system will be transported to transfer stations of the municipalities. Recyclables will be taken out for reuse, and biodegradable portion will be composted by windrow process. Inerts and rejects (60% of the total) will be transported to Regional Waste Management Centre (RWMC) for sanitary landfilling along with 50 m3/day of septic tank sludge (septage). Aim of this work is to manage leachate and septage in RWMC which consists of sanitary landfill (SLF) of 140,000 m3 capacity, approximate life of 16 years; septage treatment facility of capacity 125 m3/day with dilution water and leachate treatment facility of capacity 816 m3/day. Septage will be treated by the single-stage anaerobic sludge digester with 40 days detention period, and digested sludge will be sent to Centrifuge for dewatering. Supernatant liquor from anaerobic sludge digester (75.37 m3/day) and centrate from centrifuge (40.6 m3/day) will be discharged to the leachate treatment system for further treatment. Mixture of treated septage (116 m3/day) and leachate (700 m3/day) will be treated first in the facultative aerated lagoon-I, then in the facultative aerated lagoon-II in series. Treated effluent from the facultative aerated lagoon II will be transferred by gravity to the facultative cum sedimentation pond for further treatment. Treated effluent will be discharged in the Dankuni Canal by gravity after meeting the discharge standards of inland surface water, and a part of it will be used as dilution water in the septage treatment system and also for other uses within the RWMC.