Paulose,M M; Narayanan Nampoothiri,V N; Sreejith,P S(School of Engineering, May , 2006)
[+]
[-]
Abstract:
The study aims to the hydrodynamic characteristics of swirling fluidized bed, using large particles (Geldart D-type) selected from locally available agricultural produce (coffee beans and black pepper). The important variables considered in the present study include percentage area of opening, angle of air injection and the percentage useful area of the distributor. A total of seven distributors have been designed and fabricated for a bed column of 300 mm, namely single row vane type distributors (15˚ and 20˚ vane angle), inclined hole type distributors (15˚ and 20˚ vane angle) and perforated plate distributors. The useful area of distributor of single row vane type, three now vane-type and inclined hole-type distributors are respectively 64%,91% and 94%. The hydrodynamic parameters considered in the present study include distributor pressure drop, air velocity, minimum fluidizing velocity, bed pressure drop, bed height and the bed behaviour.
It has been observed that, in general, the distributor pressure drop decreases with an increase in the percentage area of opening, Further, and increase in the area of opening above 17% will not considerably reduce the distributor pressure drop. In the present study, for the distributor with an area of opening 17%, and corresponding to the maximum measured superficial velocity of 4.33 m/s, the distributor pressure drop obtained was 55.25mm of water. The study on the bed behavior revealed that, in a swirling fluidized bed, once swirl motion starts, the bed pressure drop increases with superficial velocity in the outer region and it decreases in the inner region. This means that, with higher superficial velocity, the air might get by-passed through the inner boundary of the bed (around the cone). So, depending on the process for which the bed is used, the maximum superficial velocity is to be limited to have an optimum bed performance.
Resmi, T R; Dr.Jacob, Chacko(Cochin University of Science & Technology, July , 2004)
[+]
[-]
Abstract:
The present study is an investigation to address relevant chemical aspects of
the three varied aquatic environments, such as mangroves, river and the estuary.
The sampling locations include a thick mangrove forest with high tidal activity, a
mangrove nursery with minimal disturbances and low tidal inundation, a highly
polluted riverine system and an estuarine site, as reference. Nutrients and
bioorganic compounds in the water column and surface sediment were estimated in
an attempt to understand the regeneration properties of these different aquatic
systems.Assessment of the trace metal pollution was also carried out.
Description:
Department of Chemical
Oceanography, Cochin University of Science
and Technology
Sumangala, K N; Dr.Sujatha, C H(Cochin University Of Science And Technology, December , 2011)
[+]
[-]
Abstract:
People in several parts of the world as well in India countenance an
immense confront to meet the basic needs of water. The crisis is not due to lack of
fresh water but its availability in adequate superiority. Environmental quality
objectives should be developed in order to define acceptable loads on the terrain.
There has been a number of initiatives in water quality monitoring but the next step
towards improving its quality hasn’t taken the required pace. Today, there is a
growing need to create awareness among citizens on the different technologies
available for improving the water quality. Monitoring facilitate to apprehend how
land and water use distress the quality of water and assist in estimating the extent of
pollution. Once these issues are recognized, people can work towards local
solutions to manage the indispensable resource effectively. Ground waters are
extremely precious resources and in many countries together with India they
represent the most important drinking water supply. They are generally
microbiologically pure and, in most cases, they do not need any treatment. This
communiqué is intended to act as a channel on the various paraphernalia and
techniques accessible for groundwater quality assessment and suggesting the
assured precautionary measures to embark on environment management. This
learning is imperative considering that groundwater as the exclusive source of
drinking water in the region which not makes situation alarming but also calls for
immediate attention.
The scope of this work is somewhat vast. Water quality in Ernakulam
district is getting deteriorated due to the fast growth of urbanization. The closure of
several water bodies due to land development and construction prevents infiltration
of rainwater into the ground and hence recharge the aquifers. Most of the aquifers
are getting polluted from the industrial effluents and chemicals and fertilizers used
in agriculture. Such serious issues require proper monitoring of groundwater and
steps are to be taken for remedial measures. This study helps in the total protection
of the rich resource of groundwater and its sustainability. Socio-economic aspect covered could be used for conducting further individual case studies and to suggest
remedial measures on a scientific basis. The specific study taken up for 15 sites can
be further extended to the sources of pollution, especially industrial and agriculture
Description:
Department of Chemical Oceanography, Cochin University of Science and
Technology
Santhosh Kumar, R; Dr. Rajendran, S(Cochin University Of Science And Technology, November , 2006)
[+]
[-]
Abstract:
The present study deals with the different hydrogeological
characteristics of the coastal region of central Kerala and a comparative
analysis with corresponding hard rock terrain. The coastal regions lie in
areas where the aquifer systems discharge groundwater ultimately into the
sea. Groundwater development in such regions will require a precise
understanding of the complex mechanism of the saline and fresh water
relationship, so that the withdrawals are so regulated as to avoid situations
leading to upcoming of the saline groundwater bodies as also to prevent
migration of sea water ingress further inland. Coastal tracts of Kerala are
formed by several drainage systems. Thick pile of semi-consolidated and
consolidated sediments from Tertiary to Recent age underlies it. These
sediments comprise phreatic and confined aquifer systems. The
corresponding hard rock terrain is encountered with laterites and
underlined by the Precambrian metamorphic rocks. Supply of water from
hard rock terrain is rather limited. This may be due to the small pore size,
low degree of interconnectivity and low extent of weathering of the country
rocks. The groundwater storage is mostly controlled by the thickness and
hydrological properties of the weathered zone and the aquifer geometry.
The over exploitation of groundwater, beyond the ‘safe yield’ limit, cause
undesirable effects like continuous reduction in groundwater levels,
reduction in river flows, reduction in wetland surface, degradation of
groundwater quality and many other environmental problems like drought,
famine etc.
Description:
Dept. of Marine Geology and Geophysics
School of Marine Sciences
Cochin University of Science and Technology
Vinayachandran, N; Narayana, A C(Cochin University of Science and Technology, June 21, 2014)
[+]
[-]
Abstract:
This is an attempt to understand the important factors that control the occurrence, development and hydrochemical evolution of groundwater resources in sedimentary multi aquifer systems. The primary objective of this work is an integrated study of the hydrogeology and hydrochemistry with a view to elucidate the hydrochemical evolution
of groundwater resources in the aquifer systems. The study is taken up in a typical coastal sedimentary aquifer system evolved under fluvio-marine environment in the coastal area of Kerala, known as the Kuttanad.
The present study has been carried out to understand the aquifer systems, their inter relationships and evolution in the Kuttanad area of Kerala. The multi aquifer systems in
the Kuttanad basin were formed from the sediments deposited under fluvio-marine and
fluvial depositional environments and the marine transgressions and regressions in the
geological past and palaeo climatic conditions influenced the hydrochemical environment in these aquifers. The evolution of groundwater and the hydrochemical processes involved in the formation of the present day water quality are elucidated from
hydrochemical studies and the information derived from the aquifer geometry and hydraulic properties.
Kuttanad area comprises of three types of aquifer systems namely phreatic aquifer underlain by Recent confined aquifer followed by Tertiary confined aquifers. These systems were formed by the deposition of sediments under fluvio-marine and fluvial environment.
The study of the hydrochemical and hydraulic properties of the three aquifer systems proved that these three systems are separate entities. The phreatic aquifers in the area
have low hydraulic gradients and high rejected recharge.
The Recent confined aquifer has very poor hydraulic characteristics and recharge to this
aquifer is very low. The Tertiary aquifer system is the most potential fresh water aquifer
system in the area and the groundwater flow in the aquifer is converging towards the central part of the study area (Alleppey town) due to large scale pumping of water for water supply from this aquifer system. Mixing of waters and anthropogenic interferences are the dominant processes modifying the hydrochemistry in phreatic aquifers. Whereas, leaching of salts and cation exchange are the dominant processes modifying the hydrochemistry of groundwater in the confined aquifer system of Recent alluvium. Two significant chemical reactions modifying the hydrochemistry in the Recent aquifers are oxidation of iron in ferruginous clays which contributes hydrogen ions and the decomposition of organic matter in the aquifer system which consumes hydrogen ions. The hydrochemical environment is entirely different in the Tertiary aquifers as the groundwater in this aquifer system are palaeo waters evolved during various marine transgressions and regressions and these waters are being modified by processes of leaching of salts, cation exchange and chemical reactions under strong reducing environment. It is proved that the salinity observed in the groundwaters of Tertiary aquifers are not due to seawater mixing or intrusion, but due to dissolution of salts from
the clay formations and ion exchange processes. Fluoride contamination in this aquifer
system lacks a regional pattern and is more or less site specific in natureThe lowering of piezometric heads in the Tertiary aquifer system has developed as consequence of large scale pumping over a long period. Hence, puping from this aquifer system is to be regulated as a groundwater management strategy. Pumping from the Tertiary aquifers with high capacity pumps leads to well failures and mixing of saline water from the brackish zones. Such mixing zones are noticed from the hydrochemical studies. This is the major aquifer contamination in the Tertiary aquifer system which requires immediate attention. Usage of pumps above 10 HP capacities in wells taping Tertiary aquifers should be discouraged for sustainable development of these aquifers. The recharge areas need to be identified precisely for recharging the aquifer systems throughartificial means.
Vinayan,V B; Dr.Seralathan, P(Cochin University of Science and Technology, February , 2009)
[+]
[-]
Abstract:
The present investigation on " Hydrology, stratigraphy, and evolution of the palaeo-lagoon (Koleland basin)in the Central Kerala coast, India" is an integrated approach based on hydrogeological,geophysical,hydrochemical and stratigraphic aspects.A strong scientific data base of the study area is generated using interpretation of well observation and water quality analysis. The salient findings of the present study are given to provide a holistic picture on the hydrogeology (including groundwater resource and its quality),stratigraphy and evolution of the palaeo-lagoon
Shadananan Nair,K; Dr.Ram Mohan,H S(Cochin University of Science and Technology, October 1, 1987)
[+]
[-]
Abstract:
Study of Kerala State in relation to the western Ghats, using The present thesis envisages a hydrometeorological various statistical techniques and the water balance concepts first developed by Thornthwaite. The first chapter of the thesis gives general introduction where the purpose and scope of the study have been given. Chapter II discusses the importance of hydrometeorological studies in general and of water balance in particular, in planning for the overall development of any region. Chapter III consists of the presentation of various geographical features of Kerala. An introduction to the physiography of the western Ghats and detailed hydroclimatic studies of the Western Ghats region which includes analysis of rainfall and the study of water balance elements form Chapter IV. In Chapter V, a detailed hydrometeorological study of Kerala State is made. Discussion of the results of the study and suggestions for optimum utilization of the available water resources for the overall development of the western Ghats region in general and Kerala in particular are made in Chapter VI.
Description:
Physical Oceanography and Meteorology Division,
School of Marine Sciences, Cochin University of Science and Technology
Susan, Mathew; Dr.Damodaran,R(Cochin University of Science & Technology, 1993)
[+]
[-]
Abstract:
The present investigation is to find the hypoxic adaptations and role of carotenoids in the anaerobic catabolism of two intertidal bivalves-Sunetta scripta and Perna viridis. Physiological and cytological responses during hypoxic stress have been studied and compared to that of sublethal heavy metal (copper) exposure using two indices : total carotenoid concentration and accumulation of lipofuscin granules. A close similarity has been observed between hypoxic exposed and copper (sublethal) exposed animals regarding the total carotenoid concentration and lipofuscin accumulation. In the case of S.scripta, the total caroteniod increase at 48h of both hypoxic and heavy metal exposure was found to be nearly 40% greater than that of the control (0h). Whereas in P.viridis, the increment in the total carotenoid concentration at 48h of hypoxic exposure and 48h of heavy metal exposure were found to be nearly 87% and 95% higher than that of the control (0h) respectively.Regarding the lipofuscin accumulation, in both S.scripta and P.viridis , the characteristic features of the granule at 48h of hypoxia is very much similar to that observed at 48h of heavy metal exposure. Thus, the present study suggests that the increase in carotenoid concentration and lipofuscin accumulation expressed by bivalves under heavy metal stress can be due to the indirect effect of hypoxia.
Description:
Division of Marine Biology, Microbiology and Biochemistry, School of Marine Sciences, Cochin university of Science and Technology
George, A I; Dr.Karunakaran, V(Cochin University of Science and Technology, June 28, 1991)
[+]
[-]
Abstract:
Vast changes have taken place in the field of institutional rural credit in India since the nationalisation of nineteen commercial banks in 1969. The supply of institutional
finance to cultivators amounted to 63.2 percent of the total credit in 1981 compared to 31.2 percent in 1971. Insti tutionalisation of agricultural credit envisaged two objectives in general. One was to emancipate cultivators and farmers from the clutches of indigenous financiers and money lenders. The second was to make farmers financially capable of adopting the new technology or improved practices in agriculture so as to increase their agricultural production and thereby contributing to the development of agriculture in India. Though vast literature on Institutional Credi t and agriculture is available, no indepth and serious work examining
thoroughly the cause of credit diversion has been undertaken so far. The present study is an attempt to fill up this gap. The study will be helpful to lending insti tutions, viz. Co-ope:r-atives,
Commercial banks and various other insti tutional agencies in connection with their lending activity_ Also, the study will help government in .formulating proper policies that will insure
a preferential treatment in favour of the most needy category of farmers and cultivators with respect to agricultural credit disbursement
Description:
Department of Applied Economics, Cochin University
of Science and Technology
Navya, Antony; Dr.Mohanan, P V(Cochin University of Science And Technology, March 25, 2014)
[+]
[-]
Abstract:
Several natural and synthetic supports have been assessed for their efficiency
for enzyme immobilization. Synthetic polymer materials are prepared by chemical
polymerization using various monomers. As a kind of important carrier, synthetic
polymer materials exhibit the advantages of good mechanical rigidity, high specific
surface area, inertness to microbial attack, easy to change their surface characteristics,
and their potential for bringing specific functional group according to actual needs.
Hence, they have been widely investigated and used for enzyme immobilization.
When it comes to the natural polymer materials, much attention has been paid
to cellulose and other natural polymer materials owing to their wide range of sources,
easy modification, nontoxic, and pollution-free, with a possibility of introducing wide
variety of functional groups and good biocompatible properties.
In this work report the use of synthetic polymer, polypyrrole and its
derivatives and natural polymers coconut fiber and sugarcane bagasse as supports for
Diastase α- amylase immobilization. An attempt was also made to functionalize both
synthetic and natural polymers using Amino-propyl triethoxysilane. Supports and their
immobilized forms were characterized via FT-IR, TG, SEM, XRD, BET and EDS
techniques. Immobilization parameters were also optimized so as to prepare stable
immobilized biocatalyst for starch hydrolysis.
Description:
Department of Applied Chemistry
Cochin University of Science and Technology