Analysis of organic nitrogen removal in municipal wastewater by reverse osmosis

The results of a pilot study that was conducted to determine the total nitrogen removal by the reverse osmosis process are presented. The organic nitrogen removal rates are compared with removals observed from three full-scale reverse osmosis facilities and four pilot studies. The results of this analysis suggest that organic nitrogen removal is variable and that reverse osmosis may not consistently produce total nitrogen levels less than 1.0 mg/L without additional treatment. Three hypotheses to explain the variability in organic nitrogen removal in the different data sets are presented.     

Assessment of risk factors in forest road design and construction activities with fuzzy analytic hierarchy process approach in Turkey

Forest road design and construction are time-consuming and complicated because various risk factors can be encountered during the process. The aim of this study is to comprehensively assess the risk factors in forest road design and construction using the fuzzy analytic hierarchy process (AHP) method in Turkey, thus contributing to the proper performance of these activities. Within the scope of the study, six main risk factors and 22 sub-risk factors were identified based on literature review. In order to determine the weights of the relevant risk factors, the opinions of three different groups [(group 1: academicians), (group 2: forest engineers (private sector employees + public sector employees)), (group 3: group 1 + group 2)] about the risk factors were obtained. Relevant risk factor weights were determined using the fuzzy AHP method. According to group 3, the most important main risk factors are technical risks and environmental risks. In addition, the most important sub-risk factors for each relevant main risk factor were incorrect road alignment, inadequate work safety in the field, insufficient capital, legal problems on the road alignment, landslide risk during road construction, and illegal logging. Differences were observed between groups 1 and 2 in the weight rankings of relevant risk factor. The results demonstrate that the fuzzy AHP method can be used effectively to assess the risks of forest road design and construction.     

Phytotoxicity of copper fungicides to guava fruits

The copper fungicides viz., Bordeaux mixture, stabilized Bordeaux mixture and copper oxychloride were found phytotoxic to guava fruits, while carbendazim, benomyl and mancozeb were non-phytotoxic. Bordeaux mixture was highly phytotoxic and caused heavy russetting, followed by stabilized Bordeaux mixture and then copper oxychloride. The higher concentrations of these fungicides were more toxic than their lower doses. Russetted fruits failed to attain normal size and thus reduced the quality of fruits to a greater extent.     

Deformation patterns in WorldSID 50th percentile dummy instrumented with IR-TRACC and RibEye™ in different loading configurations

Objective: The purpose of this study was to investigate the effect of different loading configurations on the WorldSID 50th percentile male dummy instrumented either with the Infra-Red Telescoping Rod for the Assessment of Chest Compression (IR-TRACC) or the RibEye? rib deflection measurement system.

Methods: The optical sensors of the RibEye system were used to capture the multipoint deformation of the dummy at frontal and rearward off-center locations in addition to the center of the rib location. The experimental setup consisted of 2 types of loadings: Low severity and high severity. Low-severity loading was performed by deploying a fixture-mounted side airbag on the dummy and high-severity loading was achieved by deploying a driver front airbag mounted in a similar fashion. The low-severity condition aimed at deforming the dummy’s ribs locally at off-center locations where the RibEye light emitting diodes (LEDs) were positioned to capture the deformations at those locations. The high-severity condition aimed at loading the dummy at high speed in lateral and oblique directions similar to what is experienced by dummies in side impacts.

Results: In the low-severity tests, the peak deflections, in terms of length change, were approximately 15–20?mm, whereas for the high-severity cases the peak deflections were in the range of 30–40?mm for both IR-TRACC and RibEye cases.

Conclusions: For similar physical insults, dummies with the IR-TRACC and RibEye systems showed varying results for both length changes and the shoulder forces depending on the severity and direction of loading. Under purely lateral loading, the mid-length changes with the RibEye and the 1D IR-TRACC were comparable. In the oblique loading conditions, more differences were seen with the 2 systems depending on the impact direction. The shoulder forces consistently differed between the 2 systems. In the frontal oblique low-severity cases, the ribs pivoted along the spine end and the length change was not found to be a suitable parameter to quantify rib deformation in such loading scenarios.     

Assessment of biomass and lipid productivity and biodiesel quality of an indigenous microalga Chlorella sorokiniana MIC-G5

Generation of biodiesel from microalgae has been extensively investigated; however, its quality is often not suitable for use as fuel. Our investigation involved the evaluation of biodiesel quality using a native isolate Chlorella sorokiniana MIC-G5, as specified by American Society for Testing and Materials (ASTM), after transesterification of lipids with methanol, in the presence of sodium methoxide. Total quantity of lipids extracted from dry biomass, of approximately 410–450 mg g^?1 was characterized using FTIR and ¹H NMR. After transesterification, the total saturated and unsaturated fatty acid methyl esters (FAMEs) were 43% and 57%, respectively. The major FAMEs present in the biodiesel were methyl palmitate (C16:0), methyl oleate (C18:1), and methyl linoleate (C18:2), and the ¹H NMR spectra matched with criteria prescribed for high-quality biodiesel. The biodiesel exhibited a density of 0.873 g cm^–3, viscosity of 3.418 mm² s^?1, cetane number (CN) of 57.85, high heating value (HHV) of 40.25, iodine value of 71.823 g I₂ 100 g^?1, degree of unsaturation (DU) of 58%, and a cold filter plugging point (CFPP) of –5.22°C. Critical fuel parameters, including oxidation stability, CN, HHV, iodine value, flash point, cloud point, pour point, density, and viscosity were in accordance with the methyl ester composition and structural configuration. Hence, C. sorokiniana can be a promising feedstock for biodiesel generation.     

Thermocatalytic Degradation of High Density Polyethylene into Liquid Product

Thermocatalytic degradation of high density polyethylene (HDPE) was carried out using acid activated fire clay catalyst in a semi batch reactor. Thermal pyrolysis was performed in the temperature range of 420–500 °C. The liquid and gaseous yields were increased with increase in temperature. The liquid yield was obtained 30.1 wt% with thermal pyrolysis at temperature of 450 °C, which increased to 41.4 wt% with catalytic pyrolysis using acid activated fire clay catalyst at 10 wt% of catalyst loading. The composition of liquid products obtained by thermal and catalytic pyrolysis was analyzed by gas chromatography-mass spectrometry and compounds identified for catalytic pyrolysis were mainly paraffins and olefins with carbon number range of C₆–C₁₈. The boiling point was found in the range of commercial fuels (gasoline, diesel) and the calorific value was calculated to be 42 MJ/kg.     

Correction to: Groundwater geochemical facie: implications of rock-water interaction at the Chamba city (HP), northwest Himalaya,India

Environmental Science and Pollution Research - The correct presentation of Eq. 10 is shown in this paper.     

Assessment and spatial distribution of groundwater quality in industrial areas of Ghaziabad, India

An attempt has been made in this study to evaluate the groundwater quality in two industrial blocks of Ghaziabad district. Groundwater samples were collected from shallow wells, deep wells and hand pumps of two heavily industrialized blocks, namely Bulandshahar road industrial area and Meerut road industrial area in Ghaziabad district for assessing their suitability for various uses. Samples were collected from 30 sites in each block before and after monsoon. They were analyzed for a total of 23 elements, namely, Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Se, U, V, and Zn. In addition to these elements, some other parameters were also studied viz: color, odor, turbidity, biological oxygen demand, chemical oxygen demand (COD), dissolved oxygen, total dissolved solids and total suspended solid. The water quality index was also calculated based on some of the parameters estimated. Out of the 23 elements, the mean values of 12 elements, namely, Al, As, Ca, Cd, Cr, Mg, Mn, Na, Ni, Pb, Se, and U, were higher than the prescribed standard limits. The concentrations (in milligram per liter) of highly toxic metals viz., Al, As, Cd, Cr, Ni, Pb, Se, and U, ranged from 1.33–6.30, 0.04–0.54, 0.005–0.013, 4.51–7.09, 0.14–0.27, 0.13–0.32, 0.16–2.11, and 0.10–1.21, respectively, in all groundwater samples, while the permissible limits of these elements as per WHO/BIS standards for drinking are 0.2, 0.01, 0.003, 0.05, 0.07, 0.01, 0.04, and 0.03 mg L^?1, respectively. The EC, pH, and COD in all samples varied from 0.74–4.21, 6.05–7.72, and 4.5–20.0 while their permissible limits are 0.7 dS m^?1, 6.5–8.5, and 10 mg L^?1, respectively. On the basis of the above-mentioned parameters, the water quality index of all groundwater samples ranged from 101 to 491, and 871 to 2904 with mean value of 265 and 1,174 based on two criteria, i.e., physico-chemical and metal contaminations, respectively while the prescribed safe limit for drinking is below 50. The results revealed that the groundwater in the two blocks is unfit for drinking as per WHO/BIS guidelines. The presence of elements like As, Se, and U in toxic amounts is a matter of serious concern.     

Air quality mapping using GIS and economic evaluation of health impact for Mumbai City,India

Mumbai, a highly populated city in India, has been selected for air quality mapping and assessment of health impact using monitored air quality data. Air quality monitoring networks in Mumbai are operated by National Environment Engineering Research Institute (NEERI), Maharashtra Pollution Control Board (MPCB), and Brihanmumbai Municipal Corporation (BMC). A monitoring station represents air quality at a particular location, while we need spatial variation for air quality management. Here, air quality monitored data of NEERI and BMC were spatially interpolated using various inbuilt interpolation techniques of ArcGIS. Inverse distance weighting (IDW), Kriging (spherical and Gaussian), and spline techniques have been applied for spatial interpolation for this study. The interpolated results of air pollutants sulfur dioxide (SO₂), nitrogen dioxide (NO₂) and suspended particulate matter (SPM) were compared with air quality data of MPCB in the same region. Comparison of results showed good agreement for predicted values using IDW and Kriging with observed data. Subsequently, health impact assessment of a ward was carried out based on total population of the ward and air quality monitored data within the ward. Finally, health cost within a ward was estimated on the basis of exposed population. This study helps to estimate the valuation of health damage due to air pollution.

Implications: Operating more air quality monitoring stations for measurement of air quality is highly resource intensive in terms of time and cost. The appropriate spatial interpolation techniques can be used to estimate concentration where air quality monitoring stations are not available. Further, health impact assessment for the population of the city and estimation of economic cost of health damage due to ambient air quality can help to make rational control strategies for environmental management. The total health cost for Mumbai city for the year 2012, with a population of 12.4 million, was estimated as USD8000 million.     

Influence of microbial and synthetic surfactant on the biodegradation of atrazine

The present study reports the effect of surfactants (rhamnolipids and triton X-100) on biodegradation of atrazine herbicide by strain A6, belonging to the genus Acinetobacter. The strain A6 was able to degrade nearly 80 % of the 250-ppm atrazine after 6 days of growth. The bacterium degraded atrazine by de-alkylation process. Bacterial cell surface hydrophobicity as well as atrazine solubility increased in the presence of surfactant. However, addition of surfactant to the mineral salt media reduced the rate and extent of atrazine degradation by decreasing the bioavailability of herbicide. On the contrary, addition of surfactant to atrazine-contaminated soil increased the rate and extent of biodegradation by increasing the bioavailability of herbicide. As compared to triton X-100, rhamnolipids were more efficient in enhancing microbial degradation of atrazine as a significant amount of atrazine was removed from the soil by rhamnolipids. Surfactants added for the purpose of hastening microbial degradation may have an unintended inhibitory effect on herbicide degradation depending upon contiguous condition, thus highlighting the fact that surfactant must be judiciously used in bioremediation of herbicides.