Identifying the opportunities for sustainable bitumen production in India.

The present study assessed the environmental impacts due to bitumen production in India using life cycle assessment approach. The impacts were calculated for production of 1 t of bitumen and system boundary covered extraction of resources, processing at refinery, transportation of bitumen and storage at the production site. In this study, five scenarios were considered to estimate the impacts reduction assuming different future electricity mix and thermal energy source. Crude oil extraction phase had contributed highest (91%) followed by refinery phase (4%), then transportation (3%) and at last storage of bitumen (2%). The normalization results found that the bitumen production had highest impacts on abiotic depletion fossil and lowest impact on eutrophication. Scenario S4 had the least environmental impacts and provided the overall reductions of 33% compared to the baseline scenario. Scenario S4 reduced the impacts significantly on acidification (51%), eutrophication (30%), and human toxicity (71%), but the reductions were not significant on global warming (11%) and increased the impacts on abiotic depletion fossil (1%). The results of sensitivity analysis found that thermal energy obtained from hard coal consumed during bitumen production is the most sensitive parameter for all the impact categories. The uncertainty analysis showed that the results of this study are reliable and had standard deviation less than 5% for all the impact categories. The findings of the present study will help the decision makers and concerned authorities to reduce the environmental impacts from bitumen production in India.

A comprehensive review of human health risks of arsenic and fluoride contamination of groundwater in the South Asia region.

The present study found that ∼80 million people in India, ∼60 million people in Pakistan, ∼70 million people in Bangladesh, and ∼3 million people in Nepal are exposed to arsenic groundwater contamination above 10 µg/L, while Sri Lanka remains moderately affected. In the case of fluoride contamination, ∼120 million in India, >2 million in Pakistan, and ∼0.5 million in Sri Lanka are exposed to the risk of fluoride above 1.5 mg/L, while Bangladesh and Nepal are mildly affected. The hazard quotient (HQ) for arsenic varied from 0 to 822 in India, 0 to 33 in Pakistan, 0 to 1,051 in Bangladesh, 0 to 582 in Nepal, and 0 to 89 in Sri Lanka. The cancer risk of arsenic varied from 0 to 1.64 × 1-1 in India, 0 to 1.07 × 10-1 in Pakistan, 0 to 2.10 × 10-1 in Bangladesh, 0 to 1.16 × 10-1 in Nepal, and 0 to 1.78 × 10-2 in Sri Lanka. In the case of fluoride, the HQ ranged from 0 to 21 in India, 0 to 33 in Pakistan, 0 to 18 in Bangladesh, 0 to 10 in Nepal, and 0 to 10 in Sri Lanka. Arsenic and fluoride have adverse effects on animals, resulting in chemical poisoning and skeletal fluorosis. Adsorption and membrane filtration have demonstrated outstanding treatment outcomes.

Environmental and economic assessment of waste collection and transportation using LCA: A case study.

The present study is aimed to evaluate the environmental and economic burden associated with current waste collection practices in Dhanbad city, Jharkhand, India. In this study various alternatives were suggested to mitigate these impacts by optimizing resource utilization and maximizing material recovery using life cycle approach. The functional unit adapted is the daily collection service provided for 180 tonnes of municipal solid waste generated in the study area. GaBi 10.6.1 software was used for impact assessment and impacts were assessed for five scenarios in terms of five different impact categories. This study assessed the collection services and treatment options jointly. Baseline scenario (S1) representing the current collection system had the highest impacts on all the impact categories and landfilling contributed the highest (67%) to the overall impacts on the environment. Scenario S2 involved the provision of material recovery facility and considered recycling of plastic wastes having sorting efficiency of 75% which reduced the overall impacts significantly (∼971%) compared to the baseline scenario. Scenario S3 considered composting of food waste (80% food waste sent for composting) and offered further overall impacts reduction (∼1052%) compared to the baseline scenario. In scenario S4, use of electric tippers was accounted which did not offer any significant impacts reductions. Scenario S5 considered the future electricity mix at grid (2030) in India which increased the benefits of using electric tippers. S5 had the least environmental impacts providing overall reductions of ∼1063% compared to baseline scenario and provided maximum economic benefits. Sensitivity analysis results found that variation in recycling had significant change in the environmental impacts. Considering the decrease in recycling rate from 100% to 50%, the impacts on abiotic depletion fossil increased by 136%, acidification by 176%, global warming by 11%, human toxicity by 172% and terrestrial ecotoxicity by 56%.

A critical review of the life cycle assessment studies on road pavements and road infrastructures.

In recent years, there has been a sharp rise in the number of life cycle assessment (LCA) studies related to road pavements and road infrastructures. The main aim of this study is to perform a critical analysis of various studies undertaken so far to examine goals, scopes, impact categories, life cycle phases, methods and approaches, and limitations. A total of 67 LCA studies reported in literature were analysed and categorized into four categories viz. flexible pavement; rigid pavement; flexible and rigid pavement; and road infrastructure. The analysis revealed that 80% of the studies were carried out in developed countries while just 20% of studies were from developing countries. Most of the road pavement LCA studies (∼76%) considered material and construction phase and assessed the impacts in terms of only two impact categories viz. global warming potential and energy demand. Only 10-15% of studies considered a wide range of impact categories and used commercial software such as GaBi and SimaPro for impact assessment. 19 studies were on flexible pavements, 4 on rigid pavements, 30 on both flexible and rigid pavements and 14 on infrastructure. Bridges, tunnels, drainage, lighting, and road marking were the major components of road infrastructure studied while other road infrastructures such as culverts, toll plazas, and vehicle underpasses were not included. Majority of the studies depended on secondary or background data for the development of life cycle inventory. Out of 67 studies, only 18 studies performed the sensitivity analysis while only 6 studies carried out uncertainty analysis. There is a need for inclusion of all supporting infrastructures along with road pavement, and also for paying greater attention to sensitivity and uncertainty analysis in studies pertaining to the transportation sector. During construction phase, no LCA study considered the important impacts due deforestation, defragmentation, restriction of free wildlife movement etc. Hence, future LCA road studies must evaluate the negative consequences of these as well as integrate social and economic impacts via Multi-Criteria Decision Making to make LCA a robust decision-making tool for sustainability.

Mask consumption and biomedical waste generation rate during Covid-19 pandemic: A case study of central India.

The rapid generation of biomedical waste (BMW) due to covid-19 pandemic has created burden on the existing municipal solid waste management (MSWM) system in both developed and developing countries. The substantial influx of covid patients in Maharashtra, India has influenced the pattern of BMW generation, especially for the yellow category of BMW and incineration facilities. The objective of the study was to estimate the daily face mask consumption (DFM) and BMW generation from May 2020 to August 2021 in Maharashtra, India. The study was carried out based on the confirmed covid 19 cases, population forecast, urban population (%), BMW generation rate (kg/bed/day), and so on. The data set for the each paramters were collected from web-portals, published reports based on previous studies. These data sets were further regrouped, processed and analyised using mathematical equations. The study also revealed that Mumbai, Pune, and Thane districts, India has contributed ≥ 60% of the DFM and BMW generation. It was found that the DFM by non-covid patients was higher compared to the covid patients (DCFM). Further, it was revealed that BMW generated in the months of July 2020 (152 tons/day), August 2020 (228 tons/day), September 2020 (364 tons/day), October 2020 (177 tons/day), March 2021 (405 tons/day), April 2021 (1,102 tons/day), May 2021 (705 tons/day), June 2021 (194 tons/day), and July 2021 (149 tons/day), exceeded the existing BMW treatment capcity of 132 tons/day. The sudden spike in covid-19 cases has influenced the pattern of DFM and BMW generation, espeicllay for the yellow category of BMW (BMWCY) and has increased the burden on BMW incineration facilities. The daily emission rates from BMW-incineration was in the order PM10> NO2> CO>SO2, with maximum emission of PM10 (85.61 kg of pollutant/day). The F-test was performed using one-way ANOVA to understand the influence of covid cases on daily face mask consumption. It was found that F-satistic of DCFM and BMWCY is more than the F-critical i.e., increase in covid cases had a significant effect on mass consumption rate and BMW generation.