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A new term ‘phytowaste’ has been introduced to denote that form of biomass or biowaste which comprises either the remains of the earlier live plant, or the present live plants which are weedy and are sought to be eradicated. The reasons why some species of plants, which are essential components of the ecosystems in their place of origin, become weedy when taken to new regions are enumerated. It is then shown that even as a lot of effort has been invested in either eradicating the weeds or finding ways to utilize them, neither have succeeded in controlling their spread. The prevailing means of utilizing most weeds are either not economical or are confined to their miniscule use in a few small regions of the world. In this context, the recently developed paradigm of ‘high-rate vermicomposting’ is discussed and its potential in converting billions of tonnes of ‘phytowaste’ into organic fertilizer is highlighted.

This chapter presents studies on the air quality as it occurred downwind seven major industrial estates of Puducherry, India. The survey has revealed that in most cases, the pollutant levels are exceeding the limits prescribed for ‘sensitive’ locations (schools, hospitals)—which are situated downwind these estates—by the Central Pollution Control Board (CPCB) of the Government of India. It was also seen that even as in several cases the pollutant levels are present within the limits prescribed for residential areas, (through exceeding the limits for sensitive areas), they are close to the more liberal limits for the residential areas and can begin to exceed those limits, too, if the air quality deteriorates a little further. We have compared the present findings with an earlier survey, reported in 2005. It also shows that the air quality now, in general, is inferior to what it was in 2005.

Intense current attention is focused on identifying factors which influence the extent of the emissions of greenhouse gases (GHGs) from paddy cultivation. Whereas it is now well established that the quantity of organic matter present in the soil coupled with favourable soil moisture and anoxic conditions are the principal drivers of methane emissions from paddy fields, the role of rice cultivars is much less documented or understood. Considering that even though modifications in the agricultural practices, including water management, can reduce methane generation in paddy fields, the effect of such initiatives can be reduced if the cultivar is such that it quickly and maximally transports methane to the atmosphere. Hence the physiology of the cultivar which influences the cultivar’s tendency to emit methane is of great importance. This paper summarizes the available knowledge on this subject.

In the backdrop of great paucity of information on greenhouse gas emissions from Indian wetlands in general and wetlands of peninsular South India in particular, the present studies have been carried out. They pertain to Kaliveli lake—which has a water-spread of about 70 km2 when full—situated between Chennai and Puducherry. The study reveals that, contrary to the expectation, the freshwater part of Kaliveli contributes less than 20 mg/m2 h of methane flux in all the three seasons that occur in this region.

In the another chapter of this volume, we have presented the details on the air quality of a highly industrialized suburb of the kind that occurs in all major cities of India—as also of most developing countries. The air quality was monitored by us round the year with a network of 11 sampling stations. We now present studies on the modeling of the air quality of the area, the forecasting carried out thereafter, and its implications.

A novel substrate–earthworm–vermiocompost separation (SEVS) machine is described which enables simultaneous, effective, clean, and rapid separation of finished vermicompost (vermicast), uncomposted substrate, and earthworms. The ability of the system was extensively tested with vermicomposted batches of paper waste, cow dung, and weeds—salvinia (Salvinia molesta), ipomoea (Ipomoea carnea), and lantana (Lantana camara). The effect of different batch sizes and also moisture content of the vermicast on the separation efficiency, with or without secondary separation, were tested. It is seen that SEVS machine achieves clean separation at all times and its precision is enhanced with the extent of pre-drying of the vermicast in the batch.

A study is presented which is specific to a highly industrialized suburb of Chennai, India, but is illustrative of similar regions that are present in most large cities of India as also in other developing countries. The study area covered by us consists of a large-scale petroleum refinery and several downstream petrochemical industries situated cheek-by-jowl in a cluster called the Manali Industrial Complex. Its airshed was continuously monitored with the help of eleven ambient air quality monitoring stations, set on the basis of the wind roses of the study area in different seasons. The findings have been discussed in terms of the compatibility of the airshed with the ambient air quality standard set by India’s Central Pollution Control Board.

Paddy fields, which are shallow man-made wetlands, are estimated to be responsible for ~11% of the total methane emissions attributed to anthropogenic sources. The role of water use in driving these emissions, and the apportioning of the emissions to individual countries engaged in paddy cultivation, are aspects that have been mired in controversy and disagreement. This is largely due to the fact that methane (CH4) emissions not only change with the cultivar type but also regions, climate, soil type, soil conditions, manner of irrigation, type and quantity of fertilizer added&mdash, to name a few. The factors which can influence these aspects also encompass a wide range, and have origins in causes which can be physical, chemical, biological, and combinations of these. Exceedingly complex feedback mechanisms, exerting different magnitudes and types of influences on CH4 emissions under different conditions, are operative. Similar is the case of nitrous oxide (N2O), indeed, the present level of understanding of the factors which influence the quantum of its emission is still more patchy. This makes it difficult to even understand precisely the role of the myriad factors, less so model them. The challenge is made even more daunting by the fact that accurate and precise data on most of these aspects is lacking. This makes it nearly impossible to develop analytical models linking causes with effects vis a vis CH4 and N2O emissions from paddy fields. For situations like this the bioinspired artificial intelligence technique of artificial neural network (ANN), which can model a phenomenon on the basis of past data and without the explicit understanding of the mechanism phenomena, may prove useful. However, no such model for CH4 or N2O has been developed so far. Hence the present work was undertaken. It describes ANN-based models developed by us to predict CH4 and N2O emissions using soil characteristics, fertilizer inputs, and rice cultivar yield as inputs. Upon testing the predictive ability of the models with sets of data not used in model development, it was seen that there was excellent agreement between model forecasts and experimental findings, leading to correlations coefficients of 0.991 and 0.96, and root mean square error (RMSE) of 11.17 and 261.3, respectively, for CH4 and N2O emissions. Thus, the models can be used to estimate CH4 and N2O emissions from all those continuously flooded paddy wetlands for which data on total organic carbon, soil electrical conductivity, applied nitrogen, phosphorous and potassium, NPK, and grain yield is available.

The freely and abundantly available amphibious plant Indian pennywort Bacopa monnieri (L.) Pennell was able to phytoremediate sewage (greywater) quickly and substantially in SHEFROL® (“sheet flow root level”) bioreactors, achieving reductions in the levels of several indicator parameters: suspended solids, chemical oxygen demand, biological oxygen demand, nitrogen, phosphorus, zinc, copper, nickel, and manganese to the extents of about 90%, 76–77%, 80%, 65%, 55%, 56%, 42%, and 41%, respectively at hydraulic retention times of just 6 h. As these indicators of primary, secondary, and tertiary treatments were achieved simultaneously in a single reactor compartment, the system presented in this paper promises to be simple, rapid, and economical, in achieving significant treatment of greywater.

Different authors have tried in the past to develop captive colonies of termites in their laboratories, starting with capturing of alate pairs and confining them in Petri dishes or small boxes to facilitate mating, then transferring incipient colonies into progressively larger containers. Twenty-three termite species of the genera Coptotermes, Cortaritermes, Cryptotermes, Hodotermes, Macrotermes, Mastotermes, Microtermes, Odontotermes, Pseudacanthotermes, Reticulitermes, Trinervitermes, and Zootermopsis have been explored following this method in 33 reported studies. However, in most of the attempts, incipient colonies did not grow beyond the population of a few hundred insects and tended to die off in a few months. In this paper, we report the efforts made to develop colonies of Hypotermes obscuriceps, Macrotermes convulsionarius, Microcerotermes cameroni, Odontotermes brunneus, Pericapritermes sp., and Trinervitermes biformis found in the study area. Several strategies were attempted to develop ...

Characteristics of the highly pernicious weed ipomoea ( Ipomoea carnea ) were studied before and after its vermicomposting by the earthworm ( Eisenia fetida ). The studies, supported by UV–visible and Fourier transform infrared spectroscopy (FT-IR), thermogravimetric (TG) and differential scanning calorimetry (DSC), gas chromatography–mass spectrometry (GC–MS), and scanning electron microscopy (SEM) reveal a drastic change in the characteristics. There was a sharp reduction in the carbon-to-nitrogen ratio from 26.1 to 9.9, and in humification index from 7.7 to 1.9. By all accounts there was substantial mineralization of organic matter. Complex aromatics such as lignin and polyphenols were degraded into simpler carbohydrates and lipids. GC–MS analysis showed significant fragmentation, bio-oxidation and molecular rearrangements of chemical compounds in vermicompost in comparison to those in ipomoea. SEM micrographs of ipomoea vermicompost reflected strongly disaggregated material compared to ipomoea. The phenols and alkaloids which are specifically responsible for the toxicity and allelopathy of ipomoea, were significantly degraded in the course of the weed's vermicomposting, turning it into a plant-friendly organic fertilizer. These findings make it appear possible that millions of tons of ipomoea biomass, which is generated annually but goes to waste, can be transformed into organic fertilizer.

Vermicompost, which had been derived solely by the action of the epigeic earthworm Eisenia fetida on parthenium (Parthenium hysterophorus), was tested for its impact on the germination and early growth of green gram (Vigna radiata), ladies finger (Abelmoschus esculentus) and cucumber (Cucumis sativus). Seedlings were germinated and grown in soil amended with 0 (control), 0.75, 1.5, 2, 4, 8, 20 and 40% (by weight) parthenium vermicompost. Even though parthenium is known to possess strong negative allelopathy, as also plant/animal toxicity in other forms, its vermicompost (VC) manifested none of these attributes. Rather the VC enhanced germination success, introduced plant-friendly physical features in the container media, increased biomass carbon, and was seen to promote early growth as reflected in several morphological and biochemical characteristics in plants which had received parthenium VC in comparison to those which had not. All these effects were statistically significant. Fourier Transform Infrared (FTIR) Spectrometry revealed that the phenols and the sesquiterpene lactones that are responsible for the negative allelopathic impact of parthenium were largely destroyed in the course of vermicomposting. FTIR spectra also indicated that lignin content of parthenium was reduced during its vermicomposting. The findings open up the possibility that several other invasives known for their negative allelopathy and toxicity may also produce vermicompost which may be plant-friendly and soil-friendly. It also makes it appear possible that the huge quantities of phytomass that is generated annually by parthenium can be gainfully utilized in producing organic fertilizer via vermicomposting, thereby providing a means of exercising some control over parthenium's rampant growth and invasion.

In what is believed to be the first study of its kind, the compositions of the toxic and allelopathic weed parthenium, and its vermicompost, have been investigated using UV–visible and Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, gas chromatography–mass spectroscopy, and scanning electron microscopy. The studies reveal that the weed is transformed into a totally benign organic fertilizer during the course of its vermicomposting. This is indicated by substantial improvements in the humification index, mineralization of organic matter, and degradation of complex aromatics such as lignin and polyphenols into simpler carbohydrates and lipids when parthenium is turned into its vermicompost. There are also significant fragmentation, bio-oxidation and molecular rearrangements of chemical compounds in parthenium vermicompost compared to the parent substrate. In particular, parthenin, which is principally responsible for the toxicity and allelopathy of par...

Several theoretical studies have been reported in recent years which have indicated that large-scale wind farms can have an impact on local and regional meteorology, possibly on climate. Now evidence of it based on field observations has also begun to emerge. The present paper traces the evolution of this knowledge. It discusses the theoretical studies on the possibility of wind turbines effecting climate change, and summarizes the emerging confirmation of those predictions. The concluding part of the paper assesses the implications of these findings in the context of the world׳s past experience on global warming and its present thrust to meet substantial portions of its energy needs with renewables.

In evidently the first study of its kind, vermicompost derived solely from salvinia (Salvinia molesta Mitchell), arguably the world’s most invasive and dominant aquatic weed, has been assessed for its nature and composition. Salvinia is known to contain exceptionally high concentrations of polyphenols, and has unusually ligneous leaves—the two attributes that make it strongly allelopathic and hardy, enabling it to elbow out other vegetation. The present study, supported by UV–vis and FTIR spectrometry, thermogravimetric and differential thermal analysis, and GS-MS analysis, reveals that upon vermicomposting salvinia loses its allelopathy. It happens because chemicals responsible for the alleopathy of salvinia are destroyed, transforming the weed into a potent organic fertilizer. Much of the salvinia’s lignin is also biodegraded. Scanning electron microscopy shows marked disaggregation of the material in the vermicompost as compared to well-formed matrix of salvinia leaves. The findings open up the possibility of utilizing billions of tonnes of salvinia biomass – which not only goes to waste at present but is also a cause of serious harm to the environment – in making organic fertilizer.

We report for the first time the capability of four-leaf clover (Marsilea quadrifolia), a wetland plant which grows rooted in soil, in efficiently treating sewage. The use of M. quadrifolia was made possible because of the special attributes of the SHEFROL® (SHEet Flow ROot Level) bioreactor in which it was employed. This bioreactor enables the use of free-floating aquatic plants as well as terrestrial and rooted-in-soil wetland plants by hydroponics. The plants are staked in narrow channels to enable them to support each other while sewage is made to flow rapidly as a sheet of wastewater at a level that covers only the plant roots (hence the name). It was seen that M. quadrifolia was able to treat sewage of strength varying in the chemical oxygen demand (COD) range of 600–1800 mg/L to the extent of > 80% at a hydraulic retention time (HRT) of just 4.5 h. There was a near total removal of biological oxygen demand and suspended solids while total Kjeldahl nitrogen, soluble phosphorous, and heavy metal zinc were also substantially removed. The macrophyte was equally effective when used indoors under artificial lighting, as well as when used outdoors.

Livestock production is among the most ecologically harmful of all anthropogenic activities. It has massive direct and indirect contributions to global warming besides causing widespread ecodegradation in other ways. But livestock production cannot be reduced because, as it is, the global demand for animal protein is far higher than the supply. Whereas in developed countries people get about 95 g of protein per day in their diets, of which nearly 60% is made up of animal protein, in developing countries the protein intake is only about 45 g/day and of it a mere 15% is made up of animal protein. This gap in the availability of animal protein for a large fraction of the world's population who desires it, is continuing to increase because of the increased globalization-induced rich-poor gap across the world. Besides the fact that conventional ways of animal protein production using livestock―chicken, goat, pork, beef―are highly eco-degrading; in terms of availability of pasture lands as well as enhancement in productivity of edible zoomass with inputs from science and technology, the upper limits of animal protein production have already been reached. The ocean-based food production has similarly reached unsustainable levels. As a consequence, now onwards the demand will increasingly outstrip supply. In this backdrop it is essential that we look at the potential of minilivestock, especially insects. As brought out in this paper, human beings have evolved as entomophagous species and there are even suggestions that some of the special proteins and other constituents present in the insects might have helped the human brain to develop as rapidly as it did to enable its evolution into Home sapiens. Moreover, several species of insects are prized delicacies in advanced countries like Japan, Australia, and Europe. Hence, insects are not restricted to being ‘subsistence food’ of grossly impoverished people as one might imagine though a lot of species do help the world's poor to survive. If other virtues of insects are considered― especially their high food-to-zoomass conversion efficiency, quick growth rate, enormous variety, and world-wide distribution―their potential as a much more sustainable source of animal protein than conventional livestock would become obvious.

A rapid, reproducible single step method is proposed for synthesizing platinum nanoparticles using an invasive weed lantana (Lantana camara, L). The method involves mixing of platinum (VI) solution, lantana leaf extract and ascorbic acid in appropriate concentrations and keeping the mixture at 95°C for 8 min. The collective action of ascorbic acid and leaf extract reduced the chloroplatinic acid to platinum nanoparticles and leaf extract then served the additional purpose of stabilizing the nanoparticles. The resulting nanoparticles have an average size of 35 nm and crystallized in face centred cubic symmetry. The course of the synthesis was trekked by UV-visible spectrophotometry and the characterization of the nanoparticles was done with scanning electron microscopy and confocal laser Raman spectroscopy. Particle size distribution was estimated by dynamic light scattering and the crystal structure was determined by XRD. The purity of the product was checked by EDAX.

In evidently the first study of its kind, vermicompost derived solely from a weed known to possess plant and animal toxicity was used to assess its impact on the germination and early growth of several plant species. No pre-composting or supplementation of animal manure was done to generate the vermicompost in order to ensure that the impact is clearly attributable to the weed. Whereas the weed used in this study, Lantana (Lantana camara), is known to possess strong negative allelopathy, besides plant/animal toxicity in other forms, its vermicompost was seen to be a good organic fertilizer as it increased germination success and encouraged growth of all the three botanical species explored by the authors - green gram (Vigna radiata), ladies finger (Abelmoschus esculentus) and cucumber (Cucumis sativus). In terms of several physical, chemical and biochemical attributes that were studied, the vermicompost appeared plant-friendly, giving best results in general when employed at concentrations of 1.5% in soil (w/w). Fourier transform infrared spectrometry revealed that the phenols and the sesquiterpene lactones that are responsible for the allelopathic impact of Lantana were largely destroyed in the course of vermicomposting. There is also an indication that lignin content of Lantana was reduced during its vermicomposting. The findings open up the possibility that the billions of tons of phytomass that is generated annually by Lantana and other invasives can be gainfully utilized in generating organic fertilizer via vermicomposting.

A biomimetic method of gold nanoparticles synthesis utilizing the highly invasive aquatic weed pistia (Pistia stratiotes) is presented. In an attempt to utilize the entire plant, the efficacy of the extracts of all its parts – aerial and submerged – was explored with different proportions of gold (III) solution in generating gold nanoparticles (GNPs). The progress of the synthesis, which occurred at ambient temperature and pressure and commenced soon after mixing the pistia extracts and gold (III) solutions, was tracked using UV–visible spectrophotometry. The electron micrographs of the synthesized GNPs revealed that, depending on the metal-extract concentrations used in the synthesis, GNPs of either monodispersed spherical shape were formed or there was anisotropy resulting in a mixture of triangular, hexagonal, pentagonal, and truncated triangular shaped GNPs. This phenomenon was witnessed with the extracts of aerial parts as well as submerged parts of pistia. The presence of gold atoms in the nanoparticles was confirmed from the EDAX and X-ray diffraction studies. The FT-IR spectral study indicated that the primary and secondary amines associated with the polypeptide biomolecules could have been responsible for the reduction of the gold (III) ions to GNPs and their subsequent stabilization.

We demonstrate a simple, straightforward, clean-green, single pot approach for the synthesis of bimetallic Ag/Au nanoparticles (BNPs) by using a highly invasive terrestrial weed coral vine (Antigonon leptopus). Aqueous extracts of the weed were found to reduce the metal ions to form nanosised aggregates and then stabilise them by preventing further aggregation. The efficacy of the extracts of all its parts was explored by varying the stoichiometry of reactants, temperature, pH and reaction time. The electron micrographs of the synthesised BNPs indicated the presence of particles of predominantly spherical shapes in sizes ranging from 10 to 60 nm. The presence of gold and silver atoms was confirmed from the energy dispersive X-ray, X-ray photoelectron and X-ray diffraction studies. The Fourier transform infra-red spectroscopic spectral study indicated that the phenolics (including flavonoids) and proteins contained in the plant extract could have been responsible for the formation and stabilisation of the ...

Use of aqueous extracts of leaves, stem, and roots of the obnoxious weed coral vine (Antigonon leptopus) was explored in the biomimetic extracellular synthesis of palladium nanoparticles (PdNPs). Extracts of all the three basic components of the plant-leaves, stem, and root-serve as a reducing as well as a stabilizing agent. The progress of the synthesis, which occurred at 95°C and commenced within 5 min of mixing the A. leptopus extracts and Pd(II) solutions, was tracked using UV-visible spectrophotometry. The synthesized PdNPs were characterized with electron microscopy (SEM, TEM), energy dispersive x-ray spectroscopy (EDAX), Fourier transform infrared spectroscopy (FTIR), and x-ray diffraction (XRD). The electron micrographs of the synthesized PdNPs revealed the presence of spherical particles of sizes ranging from 5 to 70 nm. The presence of Pd atoms was confirmed from the EDAX and XRD studies. The FTIR spectral study indicated that the polysaccharides and proteins in the plant extract could h...

We report for the first time the utilization of a highly invasive weed Antigonon leptopus in synthesizing gold nanoparticles. For this purpose, aqueous extracts of the weed's leaves/stem/roots served the dual purpose of reducing gold ions to uncharged metal nanoparticles and then capping the nanoparticles thus formed to stabilize them. The synthesis occurs very swiftly leading to spherical, hexagonal, or triangular nanoparticles. The influence of the key variables that control the shape/size of the gold nanoparticles (AuNPs)—concentrations of the extract relative to Au (III), temperature, interaction time, stirring, and pH-was studied employing UV–visible spectrophotometry, scanning electron microscopy, transmission electron microscopy, energy dispersive analysis of X-rays, dynamic light scattering (DLS), X-ray diffraction, and Fourier transform infrared spectroscopy. Besides being simple and rapid, the present process is distinguished by its ability to gainfully utilize an otherwise harmful plant in a manner which consumes little energy and generates no waste emissions. The AuNPs were found to catalyze the degradation of organic pollutants Congo red and Remazol Brilliant Blue R. © 2015 American Institute of Chemical Engineers Environ Prog, 2015

In a first report of its type, gainful utilization of the obnoxious weed ipomoea (Ipomoeacarnea;also known as:I.fistulosa) has been achieved by developing a procedure on its basis for clean-green one pot synthesis of bimetallic Au-Ag nanoparticles. In it the leaf and the stem extracts of the weed serve as reducing as well as stabilizing agents. With the support of Scanning Electron Microscopy, Confocal Raman Spectroscopy, and X-ray based techniques, the effect of varying metal: extract stoichiometry, temperature, and stirring on controlling the shape and size of the nanoparticles has been studied. Increase in reaction temperature is seen to favour speedier formation of nanoparticles, and of smaller average size, than occurs at ambient temperatures (27±2°C). Higher extract: metal ratios also lead to nanoparticles of larger average size. When Ag (I) and Au (III) salts are used in equal molar ratios, it generates sphere-shaped nanoparticles. All-in-all, the present work offers a non-polluting, energy saving, and cost effective route for the fabrication of bimetallic Au-Ag nanoparticles. The study indirectly provides a means of controlling ipomoea, thereby offering a means to reduce the ecological degradation that is caused by the weed.

In nature earthworms process enormous quantities of leaf litter and other forms of plant debris by ingesting them and converting them into vermicast. The latter is widely recognized as a soil-friendly and plant-friendly organic fertilizer. Earthworms also consume animal droppings but the quantities of plant biomass processed by earthworms are several times greater than the quantities of zoomass they handle. Yet, when controlled vermicomposting is done to process biodegradable solid waste, it is almost entirely focused on animal manure or food waste. Leaf litter, paper waste, terrestrial/aquatic weeds, or crop waste is rarely vermicomposted on a large scale. This paper assesses the attempts made so far to vermicompost plant-based substrates and tries to identify the reasons why the laboratory-scale studies have not evolved into larger-scale initiatives in vermicomposting such substrates. Emerging evidence of the efficacy of the high-rate vermicomposting technology in the direct processing of phytomass into fertilizers has been presented.

The history of plant-based nanoparticle synthesis is traced briefly. All the work done in this field till the present date is then summarized. The extent of the understanding of the role of pH, temperature, reducing/capping agents, metal–plant stoichiometry, stirring, light, etc., in controlling the shapes and sizes of nanoparticles is discussed.

When two or more pool fires happen to burn so close to each other that they interact, they are termed ‘multiple pool fires’ (MPF). Past accident analysis reveals that MPFs occur quite frequently in chemical process industries. Controlled experiments done so far to study MPFs have indicated that MPFs lead to increase in the fuel burning rate, flame height and heat release rate (HRR) but the nature and the extent of the impacts of different factors on these manifestations is as yet poorly understood. In this context computational fluid dynamics (CFD) appears to be a tool which can enable more detailed and realistic simulation of MPFs than other possible approaches, especially due to its ability to closely approximate the underlying physical phenomena. In tank farms there are situations where different storage tanks are placed at different elevations yet close to each other. If such tanks happen to catch fire, the resulting fires may influence each other in a manner that may be a function of the difference in the tanks’ elevation. However no CFD study has been carried out which addresses this type of situation. Hence an attempt has been made to employ CFD to study MPFs involving two pools with fuel surfaces are at different elevations. Results reveal that good correlation is possible between the experimental findings and the CFD simulations.

The vulnerability to an accident in a chemical process industry is not merely a function of the severity of a loss of confinement or the size of the area that can be affected by it. What constitutes the impact area is equally important. Vulnerability is a function of several variables—population density, quality of roads (to help disaster management), proximity to, and quality of, healthcare facilities, etc—besides an overall awareness of the risk and preparedness for the emergency. Additionally, factors such as time and climate which are not directly related to the composition of the impact area also determine it. In order to estimate the risk of an accident more precisely—so that strategies to prevent accidents or to cushion their impacts (when accidents occur) can be put in place accordingly—an index has been attempted which has the provision to factor in the vulnerability aspect. Given the fuzziness associated with the occurrence as well as the impact of any accident, this index is based on fuzzy logic.

One of the most dangerous consequences of an equipment failure in process industries resulting in a fire and/or explosion is the triggering off of the “domino effect” or “chain of accidents.” An accident in a unit may trigger an accident in another unit which, in turn, may lead to yet other accidents. To prevent such an occurance, it is imperative that hazardous units are kept safe distances away from each other. Of the types of accidents that can occur in chemical process industries, the boiling liquid expanding vapor explosion (BLEVE) is perhaps the most destructive of the forms of accidental explosions that can occur during the manufacture, storage, or transportation of chemicals in a pressure-liquefied state. The resulting blast wave, missiles, and fire or toxic release can cause great damage to life and property. There are several standards and codes which prescribe minimum safe distances to be maintained between equipment to prevent the domino effect from occurring. Of these the code prescribed by the National Fire Protection Agency (NFPA), USA, is among the ones most widely adopted for locating hazardous units. This paper evaluates the effectives of the safe distances prescribed by the NFPA 58 code in preventing a BLEVE in one vessel from causing other vessels and nearby structures to fail. The study reveals that the distances presented by NFPA are not sufficient to prevent the domino effect when the primary accident is a BLEVE.

Volatile fatty acids (VFAs), comprising mainly of acetic acid and lesser quantities of propionic and butyric acids, are generated when zoomass or phytomass is acted upon by acidogenic and acetogenic microorganisms. VFAs can be utilized by methanogens under anaerobic conditions to generate flammable methane–carbon dioxide mixtures known as ‘biogas’. Acting on the premise that this manner of VFA utilization for generating relatively clean energy can be easily accomplished in a controlled fashion in conventional biogas plants as well as higher-rate anaerobic digesters, we have carried out studies aimed to generate VFAs from the pernicious weed ipomoea (Ipomoea carnea). The VFA extraction was accomplished by a simple yet effective technology, appropriate for use even by laypersons. For this acid-phase reactors were set, to which measured quantities of ipomoea leaves were charged along with water inoculated with cow dung. The reactors were stirred intermittently. It was found that VFA production started within hours of the mixing of the reactants and peaked by the 10th or 11th day in all the reactors, effecting a conversion of over 10% of the biomass into VFAs. The reactor performance had good reproducibility and the process appeared easily controllable, frugal and robust.

The paper presents a new method for the biomimetic synthesis of gold nanoparticles (GNPs), in which a highly invasive and harmful weed Ipomoea carnea has been employed for the first time as the main bioagent. Extracts of all the three basic components of the plant – leaves, stem and root – were explored and were found to be suitable in effecting the GNP synthesis. The electron micrographs of the synthesized GNPs revealed the presence of particles of monodispersed spherical and polydispersed triangular, hexagonal, polygonal, rod, and truncated triangular shapes in sizes ranging 3–40 and 10–100nm, respectively. The presence of gold atoms was confirmed from the EDAX and X-ray diffraction studies. The FT-IR spectral study indicated that the polysaccharides and proteins in the plant extract could have been responsible for the reduction of gold ions to GNPs and the latter’s stabilization.

Hydroponics, a Greek word which literally means ‘water working’, represents horticulture without the use of soil. It has been attempted since thousands of years and descriptions are available of gardens developed wherein trees and shrubs were grown without any soil support but by supplying nutrient-rich water directly to the plant roots. In recent times, hydroponics has been explored as a means of water treatment in which biochemical, physical, and microbiological processes occurring in plant roots are harnessed to improve the quality of polluted water. Here, we present state of the art of wastewater treatment by hydroponics and introduce a novel bioreactor named SHEFROL® developed by us, of which a patent claim has been registered.

The leaves of the xerophyte Prosopis (Prosopis juliflora) were utilized to extract volatile fatty acids in a simple and ‘clean-green’ yet fairly rapid bioprocess. It involved subjecting the leaves to microbial action by acidogenic and acidogenic bacteria present in cow dung. In a single, one-pot step, the process was able to convert up to 10.7% of the total solids present in the Prosopis leaves to VFAs. It also made the spent Prosopis leaves amenable to vermicomposting.

As the sequel to the work reported in C hapter 18, we describe conversion of volatile fatty acids (VFAs), obtained from ipomoea (Ipomoea carnea), into energy in the form of biogas employing upflow anaerobic sludge blanket (UASB) reactors.

In traditional wastewater treatment systems based on vascular plants, either free-floating aquatic weeds like water hyacinth (Eichornia crassipes) are used in tanks/ponds/channels, or rooted wetland plants are used as parts of “constructed wetlands.” The novel SHEFROL® bioreactor developed by the authors (TA and SAA), of which a patent claim has been registered, has taken the technology far ahead by enabling the use of not only free-floating weeds and rooted aquatic plants, but even terrestrial plants despite the SHEFROL® systems being soil-less (hydroponic). Further, by operating at the hydraulic retention times (HRTs) of 6 h or less, SHEFROL® bioreactors are several times faster than constructed wetlands which need HRTs of 24 h or more. In this paper, studies are presented on the common weed water spinach (Ipomoea aquatica) which was explored as the main bioagent for treating sewage in bench-scale SHEFROL® bioreactors. It was seen that at a plant density of 7.8 kg/m2, and an HRT of 6 h, I. aquatica was able to remove chemical oxygen demand from wastewaters—up to the level of 1600 mg/l—to the extent of ≥80%. The plants adapted to sewage quickly and within eight days of start of the reactor, COD removal efficiency exceeded 70%. It crossed 75% by the 12th day and remained steady in the 80 ± 3% range when influent COD varied in concentration by about 3 orders of magnitude. Despite absence of soil or any other anchor, the plant roots developed extensively within the reactor. The results show that I. aquatica can be used in SHEFROL® bioreactors to efficiently and sustainably treat sewage.

A new process is described with which volatile fatty acids (VFAs) can be generated from the dried and powdered form of the pernicious amphibious weed ipomoea (Ipomoea carnea). The VFAs can then be converted to energy in the form of ‘biogas’—which is a roughly 3:1 mixture of methane and carbon dioxide—in anaerobic digesters. The process thus enables gainful utilization of an otherwise very harmful weed.

The beneficial effects of vermicast on soil fertility in general, and agriculture in particular, are widely recognized, but there are no reports on the effect of storage on vermicast quality. The present study is an attempt to cover this knowledge gap as it may assist in the formulation of guidelines for packaging and storing of vermicast in a manner that preserves the cast’s fertilizer value. Vermicast generated from paper waste was packed in airtight and partially sealed bags with and without pre-drying for 24 h. Changes in several physical, chemical, and biological properties of the castings were monitored for 3 months with weekly assessments. The results reveal that the beneficial properties of vermicast were the highest when it was fresh. There was deterioration on storage, which can be minimized if the castings are contained in airtight bags after pre-drying the casts.

Even as the world has been unsuccessfully trying to dispose off the rising quantities of its municipal solid waste (MSW) and hazardous waste (HW) in a clean manner, it has been confronted with an even more complex problem—of e-waste. Only a few countries in the developed world are able to scientifically recycle or dispose the e-waste they generate. In other developed countries only a fraction of the e-waste is properly recycled, the rest is either incinerated or sent to landfills—which are solutions that cause serious secondary problems. Worse still, a sizeable portion of the e-waste generated in the developed world is exported to developing countries where it is recycled or dumped without any concern for the gross pollution that is being caused. It can be said that if the situation vis-a-vis e-waste is posing a challenge in most developed counties, it is alarmingly bad in the developing world. In an attempt to contain the e-waste problem most of the developed world and several countries in the developing...

Multiple pool fires (MPFs) is the term used to denote pool fires which occur close enough of each other to influence each other. Even though much lesser attention has been paid to the understanding and control of MPFs, in comparison to stand-alone pool fires (SPFs), MPFs are by no means uncommon in chemical process industries. Worse, most of the MPFs–such as the ones that occurred at Buncesfield (UK) in 2005, and Jaipur (India) in 2009–are so powerful that they defy all attempts of quenching them and continue to rage till the fuel that was feeding them gets exhausted. Such fires cause enormous damage to property, besides loss of lives as occurred at Jaipur. Of the several factors that influence the destruction potential of the MPFs, pool size and separation distance between pools (S) to diameter (D) ratio (S/D) were expected to be the key factors. But no study has been done so far to analyse the effect of pool size and S/D ratio on MPFs and the present paper attempts to bridge this knowledge gap. Computational fluid dynamics (CFD) was used to model the effect of pool sizes on MPFs. The model was validated with the experimental data generated earlier by Fukuda et al. (2005). The validated code was then used to simulate the burning rate of MPFs involving pools of diameters larger than the ones used by Fukuda et al. (2005). It was observed that flame temperature, flame height, and the burning rate, all increase with an increase in the pool diameter of the participating pools in the MPFs. It was also observed that of the four S/D ratios — 0.25, 0.45, 0.66 and 1.08 — for which we have done the simulations, maximum flame height and burning rates accrues with the S/D ratio of 0.45.

In perhaps the first-ever study of its kind, the effect of vermicompost, derived solely from an allelopathic weed, on the germination, growth, and yield of a botanical species, has been carried out. In test plots, the soil was treated with the vermicompost of lantana (Lantana camara) at the rates of 5, 7.5, and 10 t ha(-1), and cluster bean (Cyamopsis tetragonoloba) was grown on it. The performance of these systems was compared with the systems in which the soil was fortified with inorganic fertilizers (IFs) in concentrations equivalent to those present in the respective vermicompost (VC) treatments. Additionally, a set of control was studied in which the soil was used without fortification by either VC or IF. It was seen that up to 51.5 % greater germination success occurred in the VC treatments compared to controls. VC also supported better plant growth in terms of stem diameter, shoot length, shoot mass, number of leaves, and leaf pigments. The positive impact extended up to fruit yield. In addition, vermicast application enhanced root nodule formation, reduced disease incidence, and allowed for a smaller number of stunted plants. The results indicate that allelopathic ingredients of lantana seem to have been totally eliminated during the course of its vermicomposting and that lantana vermicompost has the potential to support germination, growth, and fruit yield better than equivalent quantities of IFs.

When two or more pool fires burn in such close proximity of one another that they can influence each other, they are termed ‘multiple pool fires’ (MPF). The characteristics and the structure of MPFs are significantly different from that of stand-alone pool fires. Even though MPFs have known to occur fairly often in chemical process industries, much lesser work has been done towards simulation, modeling and control of MPFs as compared to stand-alone pool fires. This paper is perhaps the first-ever attempt at surveying the MPF state-of-the-art. It recounts MPF accidents and catalogs the controlled experiments that have been done to understand the mechanism and impact of MPFs. Attempts to model MPFs have been assessed and possible ways to manage MPFs have been touched upon.

Epigeic earthworms are phytophagous in habit and are believed to prefer organic matter, principally phytomass, in various degrees of decay. To check whether epigeics will ingest soil/sand even when there is luxury availability of phytomass, the present work was carried out. It was seen that not only soil but even sand particles were ingested by epigeic (Eudrilus eugeniae) tested by us, even as there was availability of phytomass and cow manure in abundance. But the consumption of sand and soil decreased as the days progressed. Moreover, the ingestion of sand and soil with phytomass and cow dung did not show any significant influence on growth and survival of earthworms. It did increase the vermicast mass due to the presence of soil/sand as was confirmed by microphotography using polarizing microscope. The findings have important implications in the design of vermireactors for maximizing their efficiency.

Of all the renewable energy sources (RESs)―except direct solar heat and light―wind energy is believed to have the least adverse environmental impacts. It is also one of the RES which has become economically affordable much before several other RESs have. As a result, next to biomass (and excluding large hydro), wind energy is the RES being most extensively tapped by the world at present. Despite carrying the drawback of intermittency, wind energy has found favor due to its perceived twin virtues of relatively lesser production cost and environment-friendliness. But with increasing use of turbines for harnessing wind energy, the adverse environmental impacts of this RES are increasingly coming to light. The present paper summarizes the current understanding of these impacts and assesses the challenges they are posing. One among the major hurdles has been the NYMBI (not in my backyard) syndrome due to which there is increasing emphasis on installing windfarms several kilometers offshore. But such moves have serious implications for marine life which is already under great stress due to impacts of overfishing, marine pollution, global warming, ozone hole and ocean acidification. Evidence is also emerging that the adverse impacts of wind power plants on wildlife, especially birds and bats, are likely to be much greater than is reflected in the hitherto reported figures of individuals killed per turbine. Likewise recent findings on the impact of noise and flicker generated by the wind turbines indicate that these can have traumatic impacts on individuals who have certain predispositions. But the greatest of emerging concerns is the likely impact of large wind farms on the weather, and possibly the climate. The prospects of wind energy are discussed in the backdrop of these and other rising environmental concerns.

The pattern of swarming of the termite Coptotermes gestroi was studied in a thickly wooded 780 acre campus of Pondicherry University, located about 12 km north of downtown Puducherry, India. In four years, C. gestroi swarms occurred 17 times of which 14 occurred in June and the remaining three in the first half of July. All the swarming occurred after sunset and after rain. In 15 instances, the alates were in the air for 15–20 min, whereas in other two cases the flights were for 35 and 60 min, respectively. There was a sharp year-to-year variation in the number of swarmings: 1, 7, 4 and 5 swarmings occurred in 2009, 2010, 2011 and 2012, respectively.

Pool fires are the most common of all process industry accidents. Pool fires often trigger explosions which may result in more fires, causing huge losses of life and property. Since both the risk and the frequency of occurrence of pool fires are high, it is necessary to model the risks associated with pool fires so as to correctly predict the behavior of such fires. Among the parameters which determine the overall structure of a pool fire, the most important is turbulence. It determines the extent of interaction of various parameters, including combustion, wind velocity, and entrainment of the ambient air. Of the various approaches capable of modeling the turbulence associated with pool fires, computational fluid dynamics (CFD) has emerged as the most preferred due to its ability to enable closer approximation of the underlying physical phenomena. A review of the state of the art reveals that although various turbulence models exist for the simulation of pool fire no single study has compared the performance of various turbulence models in modeling pool fires. To cover this knowledge-gap an attempt has been made to employ CFD in the assessment of pool fires and find the turbulence model which is able to simulate pool fires most faithfully. The performance of the standard k – ɛ model, renormalization group (RNG) k – ɛ model, realizable k – ɛ model and standard k – ω model were studied for simulating the experiments conducted earlier by Chatris et al. (2001) and Casal (2013) . The results reveal that the standard k – ɛ model enabled the closest CFD simulation of the experimental results.

Subthreshold circuits are shown to be the best candidate for satisfying the ultra-low power demand of battery-operated systems having moderate throughput. However, exponential increase in driver resistance in subthreshold region and increased global interconnect capacitance will become a major hurdle in improving the speed of subthreshold interconnects. Improving the speed of such low power circuits is a major design challenge in ultra low power domain. This paper presents a comprehensive analysis of Cu and mixed CNT bundle interconnects and investigates their performance in terms of delay and energy delay product (EDP) for future subthreshold circuits. This paper mainly contributes towards optimizing the geometrical (aspect ratio scaling) and process parameters of interconnects especially for subthreshold circuits to increase their speed. Crosstalk analysis has also been carried out with the proposed interconnect geometrical parameters. It has been found that aspect ratio scaling significantly reduces the interconnect delay and switching energy and at minimum aspect ratio, Cu wire performs better than even an optimized mixed CNT bundle for global interconnect length under subthreshold conditions.

Biodegradable wastewaters contribute as much as 6% of all anthropogenic methane emissions. High-rate anaerobic digesters have the potential to treat such wastewaters efficiently as well as enable capture of methane for use as a relatively clean energy source. This paper traces the evolution of high-rate anaerobic digester technology and provides an overview of its present capabilities. It also makes out a case for an accelerated shift from energy-intensive aerobic processes to anaerobic processes which are not only more energy-efficient but enable global warming control by methane capture.