Monitoring of Hydrocarbon Emissions in a Petroleum Refinery

In a petroleum refinery the hydrocarbon emissions which are mostly fugitive in nature are emitted from process, offsites and periodic accidental releases such as: materials storage & handling, process, equipment leaks, solvent evaporation, combustion sources, waste treatment etc. In India, the monitoring of such emissions in a refinery are limited as also the standards are not set for its limit in ambient air. Hence there is an urgent need for generating a database for such emissions. Recently in India, MoEF/CPCB has set some guidelines under CREP rules for monitoring such emissions in a refinery. A detailed monitoring of the hydrocarbon emissions from different sources in a typical 10.5 MMTPA Indian refinery is undertaken during 1999–2001 and the results are presented. It is observed that the storage tank emissions alongwith process leaks form the major contributor towards fugitive hydrocarbon emissions.     

Persistence and dissipation of dazomet in soil and tomato (lycopersicon esculentum mill) seedlings

The persistence and dissipation pattern of dazomet residues in nursery bed soil and tomato seedlings under field condition and in submerged soil and surface water under laboratory condition was studied. In nursery bed soil the half life (t _1/2) of dazomet ranged from 1.85 to 3.09 days indicating very rapid dissipation. No residues existed in tomato seedlings sown on the treated plots 3 weeks after application and the seedlings were healthy and devoid of any deformation. Under submerged condition dissipation was much faster both in soil and surface water, t_1/2 being 0.82–0.84 days only in water.     

Carbon nanotube-based nano-biosensors for detecting heavy metals in the aquatic environment

Environmental Science and Pollution Research - The identification of harmful metal ions in aquatic environments is a global concern since these contaminants can have serious consequences for...     

Determination of appropriate service quality attributes for household toilets in rural settlements of India based on user perception

In many developing countries, including India, governments have implemented programs for improvement of environment and health in rural settlements through the provision of a subsidized household toilet with specifications selected and benchmarked from the experts’ perspective with only partial consideration of users’ perception. Provision of household toilets with specifications or service quality as perceived by users is a requirement for the sustainability and sustained use of toilet infrastructure. Users do not judge only the overall quality of a service but also base their judgment on a few attributes which are either perceived to be relatively more important or where there is a wider gap between expectation and perception . This paper presents a review of the service quality attributes of the household toilet as found in the relevant literature and provides a step-by-step approach for identifying appropriate attributes based on users’ perspective. While an initial list of attributes was developed based on literature review, initial selection and modifications of the attributes’ definition and units were carried out as per our judgment. This list was further modified through focus groups discussions and incorporating expert opinions. The final list of attributes is selected based on the stated importance level of attributes as perceived by users. The study finds that the attributes prioritized by the users are different from the experts. While government policies emphasize on the construction of toilet, maintenance of toilet is found an important issue for the users.     

Chemical characterization of precipitation at a coastal site in Trombay, Mumbai, India

Precipitation is the best scavenger for the particulates and dissolved gaseous pollutants present in the atmosphere. The chemical composition of precipitation is dominated by a number of in-cloud and below-cloud scavenging processes. The present study is aimed at analyzing the chemical composition of rainwater in the relatively less industrialized part of Mumbai. The pH of rainwater in this region ranges from 4.8 to 6.4. The percentage contributions of ions were calculated and the major contributing ions were calcium (28%), chloride (23%), sodium (18%), sulfate (14%), magnesium (11%), ammonium (4%), potassium (1%), and nitrate (1%). The correlation coefficient is highest for Na and Cl (r ²?=?0.99), giving a clear indication of contribution from sea salt. Sulfate and nitrate ions also show a very good correlation (r ²?=?0.90), which may be due to their coemission from fossil fuel combustion. Acidification caused by these ions is neutralized by Ca, Mg, and NH₄ ions. The neutralization effect due to these ions is validated by calculating the neutralization factor (NF). The NF values are in the order Ca > Mg > NH₄. The major source contributors for the ions in precipitation are sea salt (Na, Cl, and K) and fossil fuel combustion (SO₄ and NO₃). These assumptions are supported by the values of wet-only ratio, enrichment factor, and percent sea salt fraction.     

Monitoring of organochlorine pesticide residues in the Indian marine environment.

Organochlorine pesticide residues in sediment and fish samples collected from the east and west coasts of India are presented. HCH isomers and DDT and its metabolites are the predominantly identified compounds in most of the samples. Despite the higher quantity of consumption, HCH and DDT levels in fish in India were lower than those in temperate countries suggesting a lower accumulation in tropical fish, which could be due to rapid volatilization and degradation of these insecticides in the tropical environment. The predominance of alpha- and beta-HCH reflect the use of technical grade HCH in India. The high temperature in the tropics also enhances the elimination rate of chemicals in fish, as the biological half-lives of semivolatile compounds such as DDT are short at high temperature.     

Trace metals and organometals in selected marine species and preliminary risk assessment to human beings in Thane Creek area, Mumbai

Trace metals and organometals were estimated in different types of marine organisms (fish, bivalve, crab and prawn) collected from the Trans-Thane Creek area, Mumbai. Thane Creek area is considered as most polluted area due to industrial discharges. Potential risks associated with consumption of marine organisms collected from this particular area to human beings were assessed. Concentrations of ten trace elements (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb and Zn) in the edible part of marine organisms were analysed by atomic absorption spectrometer and differential pulse anodic stripping voltametric technique. Methyl mercury and tributyl tin were estimated using gas chromatograph-mass spectrometer in combination with solid phase micro extraction (SPME). An assessment of the risk on human beings due to consumption of marine organism was undertaken using toxic reference benchmark, namely the reference dose (RfD). The hazard index (HI), sum of hazard quotients calculated for all the pollutant showed that the risks from consumption of fish and marine organisms as a whole were generally low and are within safe limits.     

A Comparative Ergonomics Postural Assessment of Potters and Sculptors in the Unorganized Sector in West Bengal,India

Potters and sculptors perform their work in very awkward postures. The purpose of this study was to analyse these postures. The modified Nordic questionnaire was used to analyse musculoskeletal discomfort. Rapid entire body assessment (REBA) and rapid upper limb assessment (RULA) were used to evaluate the subjects’ postures. There were no significant differences between times of discomfort and the group of subjects. However, there were significant differences in discomfort in different body parts. The analysis indicated that various body postures were harmful to the subjects and that there were profound deviations from natural curvature of various body parts due to awkward body postures. Ergonomics intervention was required to improve the quality of life.     

Integration of pen aquaculture into ecosystem-based enhancement of small-scale fisheries in a macrophyte dominated floodplain wetland of India

Environmental Science and Pollution Research - The rapid degradation, overexploitation, and encroachment of floodplain wetlands have led to considerable decline in fish diversity and production...