Performance and exhaust emission characteristics investigation of compression ignition engine fuelled with microalgae biodiesel and its diesel blends

Biofuels extracted from plant biomass can be used as fuel in CI engines to lower a hazardous atmospheric pollutant and mitigate climate risks. Furthermore, its implementation is hampered by inevitable obstacles such as feedstocks and the crop area required for their cultivation, leading to a lack of agricultural land for the expansion of food yields. Despite this, microalgae have been discovered to be the most competent and unwavering source of biodiesel due to their distinguishing characteristics of being non-eatable and requiring no cropland for cultivation. The objectives of this paper was to look into the potential of a novel, formerly underappreciated biodiesel from microalgae species which could be used as a fuel substitute. Transesterification is being used to extract the biodiesel. Microalgae are blended with petroleum diesel in percentage to create microalgae blends (MAB) as needed for experimentation. The impact of biodiesel on performance as well as exhaust emission attributes of a 1-cylinder diesel engine was experimentally studied. Compared to petroleum diesel, different blend of microalgae biodiesel showed a decline in torque and hence brake power, resulting in an average fall of 7.14 % in brake thermal efficiency and 11.54 % increase in brake-specific fuel consumption. There were wide differences in exhaust emission characteristics, including carbon monoxide and hydrocarbon, as the blend ratio in diesel increased. Moreover, nitrogen oxides and carbon dioxides increase in all algae biodiesel blends, but they are still within the acceptable range of petroleum diesel.

     

Impacts of renewable energy on output elasticities and implications for factor shares in European countries: fresh evidence from panel threshold models

Environmental Science and Pollution Research - The objective of this paper is to examine, for a panel of seven countries from the European Union, spanning the period 1986–2015, whether the...     

Health cost of salinity contamination in drinking water: evidence from Bangladesh

Environmental Economics and Policy Studies - This study estimates health cost of salinity contamination in drinking water in the severe salinity affected three south-western districts of...     

Identifying the local factors of resilience during cyclone Hudhud and Phailin on the east coast of India

Ambio - The vulnerabilities of coastal communities have increased in recent years, as more people have to live in hazard-prone areas due to population growth. The east coast of India is one such...     

Effect of heavy metals on tissue-specific antioxidant response in Indian major carps

Concentrations of heavy metals (Cu, Ni, Zn, Cd and Pb) were measured in sediments, water and liver and kidney tissues of three Indian major carps (Labeo rohita, Catla catla and Cirrhinus cirrhosus), belonging to two different weight groups (250 and 500 g), collected from ponds at two different sites (Nalban bheri and Diamond Harbour). The tissues were analysed for the levels of different antioxidant defence systems such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GRd), glutathione S-transferase (GST), glutathione (GSH) and malondialdehyde (MDA). Concentrations of all the metals were significantly higher (P < 0.05) in sediment, water and the tissues from Nalban bheri compared to those in Diamond Harbour. Metal concentrations were the lowest in C. cirrhosus, which increased with an increase in fish weight, and the liver accumulated higher amount of metals than the kidney. Activities of all enzymatic and non-enzymatic antioxidant parameters except GPx and GRd were significantly higher (P < 0.05) in the tissues from Nalban bheri than those in Diamond Harbour. Significant multicollinearity was found in the values of SOD, CAT, GST, GRd, GPx and MDA with Pb, Cu and Ni in all three fish species at Nalban and with Cd in L. rohita and C. catla. Principal component analysis results revealed that stress response in a polluted site was directly regulated by an amalgamation of GSH profile and the levels of MDA in a synchronized manner. The study indicated a tissue-specific and species-specific difference for heavy metal-induced oxidative stress response in fish and a correlation between different heavy metals and individual oxidative stress markers.     

Distribution of PM2.5 and PM10-2.5 in PM10 Fraction in Ambient Air Due to Vehicular Pollution in Kolkata Megacity

This research paper aims at establishing baseline PM₁₀ and PM_2.5 concentration levels, which could be effectively used to develop and upgrade the standards in air pollution in developing countries. The relative contribution of fine fractions (PM_2.5) and coarser fractions (PM_10-2.5) to PM₁₀ fractions were investigates in a megacity which is overcrowded and congested due to lack of road network and deteriorated air quality because of vehicular pollution. The present study was carried out during the winter of 2002. The average 24h PM₁₀ concentration was 304 μg/m³, which is 3 times more than the Indian National Ambient Air Quality Standards (NAAQS) and higher PM₁₀ concentration was due to fine fraction (PM_2.5) released by vehicular exhaust. The 24h average PM_2.5 concentration was found 179 μg/m³, which is exceeded USEPA and EU standards of 65 and 50 μg/m³ respectively for the winter. India does not have any PM_2.5 standards. The 24 h average PM_10-2.5 concentrations were found 126 μg/m³. The PM_2.5 constituted more than 59% of PM₁₀ and whereas PM₁₀-PM_2.5 fractions constituted 41% of PM₁₀. The correlation between PM₁₀ and PM_2.5 was found higher as PM_2.5 comprised major proportion of PM₁₀ fractions contributed by vehicular emissions.     

Mobility of spiromesifen in packed soil columns under laboratory conditions

On percolating water equivalent to 1,156 mm of rainfall, spiromesifen formulation did not leach out of 25-cm long columns, and 62.7 % of this was recovered in 5–10-cm soil depth. In columns treated with the analytical grade, 52.40 % of the recovered spiromesifen was confined to 0–5-cm soil depth, with 0.04 % in leachate fraction, suggesting high adsorption in soil. Results revealed that percolating 400 mL of water, residues of enol metabolite of spiromesifen was detected up to 20–25-cm soil layer, with 23.50 % residues of spiromesifen in this layer and 1.73 % in the leachate fraction indicating that metabolite is more mobile as compared to the parent compound. Results suggested a significant reduction in leaching losses of enol metabolite in amended soil columns with 5 % nano clay, farmyard manure (FYM), and vermicompost. No enol spiromesifen was recovered in the leachate in columns amended with nano clay, vermicompost, and FYM; however, 85.30, 70.5, and 65.40 %, respectively, was recovered from 0–5 cm-soil depth of column after percolating water equivalent to 1,156 mm of rainfall. Spiromesifen formulation is less mobile in sandy loam soil than analytical grade spiromesifen. The metabolite, enol spiromesifen, is relatively more mobile than the parent compound and may leach into groundwater. The study suggested that amendments were very effective in reducing the downward mobility of enol metabolite in soil column. Further, it resulted in greater retention of enol metabolite in the amendment application zone.     

Physico-chemical assessment of paper mill effluent and its heavy metal remediation using aquatic macrophytes—a case study at JK Paper mill, Rayagada, India

The present investigation aims to assess the phytoremediation potential of six aquatic macrophytes, viz. Eichhornia crassipes, Hydrilla verticillata, Jussiaea repens, Lemna minor, Pistia stratiotes and Trapa natans grown in paper mill effluent of JK Paper mill of Rayagada, Orissa, for remediation of heavy metals. The experiment was designed in pot culture experiments. Assessment of physico-chemical parameters of paper mill effluent showed significant decrease in pH, conductivity, total dissolved solids, total suspended solids, chlorine, sulphur, biological and chemical oxygen demand after growth of macrophytes for 20 days. Phytoremediation ability of these aquatic macrophytic species for copper (Cu) and mercury (Hg) was indicated by assessing the decrease in the levels of heavy metals from effluent water. Maximum reduction (66.5 %) in Hg content of untreated paper mill effluent was observed using L. minor followed by T. natans (64.8 %). L. minor showed highest reduction (71.4 %) of Cu content from effluent water followed by E. crassipes (63.6 %). Phytoextraction potential of L. minor was remarkable for Hg and Cu, and bioaccumulation was evident from bioconcentration factor values, i.e. 0.59 and 0.70, respectively. The present phytoremediation approach was considered more effective than conventional chemical treatment method for removing toxic contaminants from paper mill effluent.     

Monitoring and assessment of airborne fungi in Kolkata, India, by viable and non-viable air sampling methods

The composition and variability of airborne fungal spores were studied using two complementary sampling methods in an outdoor environment in Kolkata suburb for 2 years, from November 2002 to October 2004. For monitoring the total fungal spore burden in the air, Burkard 7-day volumetric sampler was used, whereas Andersen two-sage viable sampler was used for isolating the cultivable airborne fungi. Among the 37 fungal spore types identified in the air samples, the predominant ones were Cladosporium, unidentified ascospores, unidentified basidiospores, Aspergilli/Penicilli, Nigrospora, Periconia, Chaetomium, Drechslera, Alternaria, Coprinus, Ganoderma, Pithomyces, and rust spores. Only six fungal spore types (Alternaria, Aspergilli/Penicilli, Cladosporium, Curvularia, Drechslera, and Nigrospora) were recovered in common by the two samplers. For Aspergilli/Penicilli, Drechslera, and Nigrospora, the spore concentration was underestimated in the non-viable sampling method (Burkard sampler). In general, higher spore count was recorded in winter. The highest fungal species variability was observed in early monsoon (June). Relative humidity could significantly predict the seasonal periodicity of the maximum number of airborne spores. The total airborne fungi concentration recorded in the study (15-16?×?10(3) spores m(-3) of air) was lower than the proposed threshold limit value for clinical significance, suggesting apparently no or less airborne-fungi-exposure-related health risk in the sampling area. Cladosporium cladosporioides was recorded beyond the proposed threshold limit value in January 2003 and March 2004; Aspergillus fumigatus and Aspergillus nidulans in winter that might have posed considerable health risk to sensitized individuals.     

Association between road traffic noise and prevalence of coronary heart disease

There is an established evidence that exposure to high levels of road traffic noise is associated with elevated risk of coronary heart disease (CHD). The results however have been heterogeneous and mostly inconclusive. The present investigation aimed to examine this association in adult subjects, with a secondary aim of identifying potentially vulnerable sub-populations. Similar studies have never been reported from Indian population. For exposure assessment, the time-weighted road traffic noise indicator, L _den, was used as a continuous and categorical predictor. A cross-sectional study was designed, and sociodemographic and lifestyle- and health-related characteristics were recorded for 909 (533 females and 376 males) subjects aged 18–80 years. The respondents living in areas with L _den?<?60 dB(A) were designated as the reference group. Odds for self-reported CHD in relation to traffic noise exposure were estimated by univariate and multifactorial logistic regression with adjustments for potential confounders and effect modifiers. The adjusted odds ratio (OR) for self-reported CHD was 1.72 (95 % CI 1.36–2.19) per 5 dB(A) increase of L _den (range 55–80 dB(A)). A gender-related risk difference was observed among male (OR 1.47 (1.07–2.02)) and female (OR 1.83 (1.27–2.65)) respondents. A stronger effect for subjects in the age group 55–64 years old was found, with age, residence period, body mass index, and self-reported stress being significant confounders. This study suggests epidemiological evidence that exposure to road traffic noise of L _den?>?65 dB(A) may be associated with occurrence of CHD in adult subjects. A trend was observed indicating increasing risk with higher exposure levels. The study results are also suggestive of higher risk of outcome among those with other chronic ailments (diabetes, pulmonary, or renal issues) and residing in the same location in excess of 15 years. Orientation of bedroom windows was identified as a significant effect modifier.