Ramesh, A; Dr.Madhu, G(Cochin University of Science And Technology, October 18, 2012)
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Abstract:
Cement industry ranks 2nd in energy consumption among the industries
in India. It is one of the major emitter of CO2, due to combustion of fossil fuel
and calcination process. As the huge amount of CO2 emissions cause severe
environment problems, the efficient and effective utilization of energy is a
major concern in Indian cement industry. The main objective of the research
work is to assess the energy cosumption and energy conservation of the Indian
cement industry and to predict future trends in cement production and
reduction of CO2 emissions. In order to achieve this objective, a detailed
energy and exergy analysis of a typical cement plant in Kerala was carried out.
The data on fuel usage, electricity consumption, amount of clinker and cement
production were also collected from a few selected cement industries in India
for the period 2001 - 2010 and the CO2 emissions were estimated. A complete
decomposition method was used for the analysis of change in CO2 emissions
during the period 2001 - 2010 by categorising the cement industries according
to the specific thermal energy consumption. A basic forecasting model for the
cement production trend was developed by using the system dynamic approach
and the model was validated with the data collected from the selected cement
industries. The cement production and CO2 emissions from the industries were
also predicted with the base year as 2010. The sensitivity analysis of the
forecasting model was conducted and found satisfactory. The model was then
modified for the total cement production in India to predict the cement
production and CO2 emissions for the next 21 years under three different
scenarios. The parmeters that influence CO2 emissions like population and
GDP growth rate, demand of cement and its production, clinker consumption
and energy utilization are incorporated in these scenarios. The existing growth
rate of the population and cement production in the year 2010 were used in the
baseline scenario. In the scenario-1 (S1) the growth rate of population was
assumed to be gradually decreasing and finally reach zero by the year 2030,
while in scenario-2 (S2) a faster decline in the growth rate was assumed such
that zero growth rate is achieved in the year 2020. The mitigation strategiesfor the reduction of CO2 emissions from the cement production were identified
and analyzed in the energy management scenarioThe energy and exergy analysis of the raw mill of the cement plant revealed
that the exergy utilization was worse than energy utilization. The energy analysis
of the kiln system showed that around 38% of heat energy is wasted through
exhaust gases of the preheater and cooler of the kiln sysetm. This could be
recovered by the waste heat recovery system. A secondary insulation shell was
also recommended for the kiln in the plant in order to prevent heat loss and
enhance the efficiency of the plant. The decomposition analysis of the change in
CO2 emissions during 2001- 2010 showed that the activity effect was the main
factor for CO2 emissions for the cement industries since it is directly dependent on
economic growth of the country. The forecasting model showed that 15.22% and
29.44% of CO2 emissions reduction can be achieved by the year 2030 in scenario-
(S1) and scenario-2 (S2) respectively. In analysing the energy management
scenario, it was assumed that 25% of electrical energy supply to the cement plants
is replaced by renewable energy. The analysis revealed that the recovery of waste
heat and the use of renewable energy could lead to decline in CO2 emissions 7.1%
for baseline scenario, 10.9 % in scenario-1 (S1) and 11.16% in scenario-2 (S2) in
2030. The combined scenario considering population stabilization by the year
2020, 25% of contribution from renewable energy sources of the cement industry
and 38% thermal energy from the waste heat streams shows that CO2 emissions
from Indian cement industry could be reduced by nearly 37% in the year 2030.
This would reduce a substantial level of greenhouse gas load to the environment.
The cement industry will remain one of the critical sectors for India to meet
its CO2 emissions reduction target. India’s cement production will continue to
grow in the near future due to its GDP growth. The control of population,
improvement in plant efficiency and use of renewable energy are the important
options for the mitigation of CO2 emissions from Indian cement industries
Description:
Division of safety and Fire Engineering,
School of Engineering, Cochin University of Science and Technology
Udayakumar, P; Dr.Ouseph, P P(Cochin University Of Science And Technology, July 19, 2012)
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Abstract:
The nearshore marine ecosystem is a dynamic environment impacted by
many activities, especially the coastal waters and sediments contiguous to major
urban areas. Although heavy metals are natural constituents of the marine
environment, inputs are considered to be conservative pollutants and are
potentially toxic, accumulate in the sediment, are bioconcentrated by organisms
and may cause health problems to humans via the food chain. A variety of
metals in trace amounts are essential for biological processes in all organisms,
but excessive levels can be detrimental by acting as enzyme inhibitors.
Discharge of industrial wastewater, agriculture runoff and untreated sewage
pose a particularly serious threat to the coastal environment of Kerala, but there
is a dearth of studies in documenting the contaminant metals. This study aimed
principally to assess such contamination by examining the results of heavy
metal (Cu, Pb, Cr, Ni, Zn, Cd and Hg) analysis in seawater, sediment and
benthic biota from a survey of five transects along the central and northern
coast of Kerala in 2008 covering a 10.0 km stretch of near shore environment in
each transect. Trophic transfer of metal contaminants from aquatic invertebrates
to its predators was also assessed, by employing a suitable benthic food chain
model in order to understand which all metals are undergoing biotransference
(transfer of metals from a food source to consumer).The study of present contamination levels will be useful for potential
environmental remediation and ecosystem restoration at contaminated sites and
provides a scientific basis for standards and protective measures for the coastal
waters and sediments. The usefulness of biomonitor proposed in this study
would allow identification of different bioavailable metals as well as provide an
assessment of the magnitude of metal contamination in the coastal marine
milieu. The increments in concentration of certain metals between the predator
and prey discerned through benthic food chain can be interpreted as evidence of
biotransference.
Description:
School of Environmental Studies
Cochin University of Science and Technology
Jaison, C A; Dr.Sivanandan, Achari V(Cochin University of Science And Technology, October , 2012)
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Abstract:
Everywhere, on the coastal belt it is proved without doubt that the pristine ground
water quality was severely deteriorated after the 26 December 2004 Indian Ocean
Tsunami. But how far is more relevant, as it is decided by the so-called pre-tsunamic
situation of the region. In water quality studies it is this reference finger print which
earmarks regional ground water chemistry based on which the monthly variability
could rationally be interpreted. This Ph D thesis comprises the testing and evaluation of the facts: whether there is any significant difference in the water quality parameters under study between stations
and between months in Tsunami Affected Dug Wells (TADW). Whether the selected
water quality parameters vary significantly from BIS and WHO standards. Whether
the water quality index (WQI) differ significantly between Tsunami Affected Dug
Wells (TADW) and Bore Wells (BW). Whether there is any significant difference in
the water quality parameters during December 2005 and December 2008. Is there any
significant change in the Water Quality Parameters before 2001 and after tsunami
(2005) in TADW.
Description:
School of Environmental Studies, Cochin University of Science and Technology
Tina,Sebastian; Dr.Sudha Kartha,C; Dr.Vijayakumar, K P(Cochin University of Science & Technology, August , 2009)
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Abstract:
Aim of the present work was to automate CSP process, to deposit and
characterize CuInS2/In2S3 layers using this system and to fabricate devices using
these films.An automated spray system for the deposition of compound
semiconductor thin films was designed and developed so as to eliminate the manual
labour involved in spraying and facilitate standardization of the method. The system
was designed such that parameters like spray rate, movement of spray head, duration
of spray, temperature of substrate, pressure of carrier gas and height of the spray head
from the substrate could be varied. Using this system, binary, ternary as well as
quaternary films could be successfully deposited.The second part of the work deal with deposition and characterization of
CuInS2 and In2S3 layers respectively.In the case of CuInS2 absorbers, the effects of
different preparation conditions and post deposition treatments on the optoelectronic,
morphological and structural properties were investigated. It was observed
that preparation conditions and post deposition treatments played crucial role in controlling the properties of the films. The studies in this direction were useful in
understanding how the variation in spray parameters tailored the properties of the
absorber layer. These results were subsequently made use of in device fabrication
process.Effects of copper incorporation in
In2S3 films were investigated to find how the diffusion of Cu from CuInS2 to In2S3
will affect the properties at the junction. It was noticed that there was a regular
variation in the opto-electronic properties with increase in copper concentration.Devices were fabricated on ITO coated glass using CuInS2 as absorber and
In2S3 as buffer layer with silver as the top electrode. Stable devices could be
deposited over an area of 0.25 cm2, even though the efficiency obtained was not high.
Using manual spray system, we could achieve devices of area 0.01 cm2 only. Thus
automation helped in obtaining repeatable results over larger areas than those
obtained while using the manual unit. Silver diffusion on the cells before coating the
electrodes resulted in better collection of carriers.From this work it was seen CuInS2/In2S3 junction deposited through
automated spray process has potential to achieve high efficiencies.
Description:
Department of Physics,
Cochin University of Science and Technology