About Me |
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Working with this great abode of learning since December 2008,Prior to this ,worked with J N T U,Anantapuramu campus (Adhoc basis)[for 3 years] , S M S Pharmaceuticals [for 18 Months] Education: B.Tech- Chemical Engineering- GMR Institute of Technology ,Rajam,AP M.Tech- Chemical Engineering - SriVenkateswara University. Ph.D- Chemical Engineering -Andhra University |
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Fast pyrolysis of the crushed Delonix regia seed was carried out in a semi-batch reactor at a temperature ranging from 400 to 650°C with an objective to produce bio-oil. The effect of temperature to obtain an optimum condition for maximum bio-oil yield and the composition of pyrolysis product were investigated. The maximum bio-oil yield was found to be 48 wt% at pyrolysis temperature of 600°C. The chemical composition of bio-oil obtained at optimum condition was analysed using Fourier-transformed infrared spectroscopy and Gas chromatography–mass spectrometry. The chemical analysis of the biofuel showed the presence of hydrocarbons in major, aldehydes, ketones, amides, nitriles, etc. The composition and fuel characteristics of the pyrolysis oil obtained in this work show that it may potentially be used as a renewable fuel and chemical feedstock.
In the present study electrochemical reactions are carried out in bubble columns for achieving enhanced mass transfer rates. The mass transfer coefficient was computed from measured limiting currents at the electrodes fixed flush with the inner surface of the perspex tube wall which acted as test section. A string of cones arranged concentrically on a rod was used as the turbulent promoter. Improvements in the mass transfer coefficient due to cone elements are 100% when compared with the bubble column without any promoter. In the present study the effect of pertinent dynamic variables such as superficial gas velocity and liquid velocity; and geometric variables such as cone diameter, pitch, half apex angle of cone and rod diameter on mass transfer coefficient have been analyzed graphically. Correlation equations that gave best fit were obtained from least squares regression analysis, which can be used for the prediction of mass transfer coefficient.
The present investigation consists of flow of gas and liquid in the upward direction in a vertical column which is called as gas-liquid upflow bubble column. In the present work, electrochemical reactions are carried out in bubble columns for achieving enhanced mass transfer rates. Mass transfer coefficient was obtained from limiting current. A string of doublecones arranged on a rod was used as the turbulent promoter. Improvements in mass transfer coefficient due to doublecone elements are 40% when compared with the bubble column without any promoter. In the present study, the effect of variables such as superficial gas and liquid velocities, doublecone diameter, pitch, half apex angle of cone and rod diameter on mass transfer coefficient have been analyzed graphically. Correlation equation that gave best fit was obtained from least squares regression analysis, which can be used for the prediction of mass transfer coefficient.
Kinetic studies of esterification of propionic acid with cyclohexanol were carried out using sulplhuric acid as catalyst. Experiments were conducted in a stirred, temperature controlled batch reactor. The reaction is homogeneous. The effects of different variables that influence the rate constant such as temperature, catalyst concentration and mole ratio or reactants were studied. The reaction rate followed second order with respect to the acid concentration. The mole ratio is varied between 0.5 and 2.0, temperature between 50 and 70oC and catalyst concentration between 1.5 and 4.5 weight percent. An equation is obtained for the prediction of rate constant.
Experiments were carried out to know the influence of flow variables and geometric parameters of an internal on mass transfer coefficients in a three-phase fluidized bed. The internal constitutes a string of doublecones arranged on a central rod which is placed coaxially in the three-phase fluidized bed. The flow system investigated was nitrogen, electrolyte and spherical glass balls as gas, liquid and solid phases respectively. Limiting current technique was employed to obtain mass transfer data. Using doublecone promoter, mass transfer rate increased by 20%. The present study revealed that gas and liquid velocities had no effect on mass transfer coefficient. The influence of pitch on mass transfer coefficient was found to be significant. Appropriate correlations were provided for the prediction of mass transfer coefficient in terms of pertinent variables.
Enhancement of mass transfer coefficient is highly
desirable for economic design of process equipment. The present
study is essentially carried out to know the effect of flow variables
such as gas and liquid velocities and geometric parameters of the
internal on mass transfer coefficients in a three phase fluidized
bed. The mass transfer coefficient data were obtained using a
string of cones internal in a three-phase fluidized bed
electrochemical reactor. The flow system investigated was
nitrogen, a fluid electrolyte and spherical glass beads as gas,
liquid and solid phases respectively. Limiting current technique
was employed to obtain mass transfer data. The internal
comprises of a string of cones arranged concentrically on a
central rod which is placed coaxially in a three phase fluidized
bed. The presence of internal in three phase fluidized beds
augmented the mass transfer coefficient significantly. In the
present investigation it was found that the effect of gas velocity,
liquid velocity, rod diameter and cone diameter was only
marginal. However, the influence of pitch, half apex angle of
cone and particle diameter was found to be significant.
Correlations were developed based on least squares regression
analysis for the prediction of mass transfer coefficient in terms of
pertinent variables.
Experimental investigations were carried out to determine the possible levels of augmentation in mass transfer coefficient in gas–liquid flow system using a string of inverted cones. It is noticed that the mass transfer coefficient nearly doubled due to insertion of this promoter. Studies revealed that gas velocity, liquid velocity, pitch and rod diameter have no effect on mass transfer coefficient. The mass transfer coefficient increased with base diameter of cone. An empirical correlation is also obtained to predict mass transfer coefficient.
An investigation had been carried out to study the effect on mass transfer between flowing fluid and column
wall in gas-liquid system with different internals. Doublecone, disc and sphere promoters were the displaced devices
used. The liquid phase was an electrolyte solution. The gas phase was nitrogen. The study revealed that the velocities of
fluids and location promoter had no effect on mass transfer coefficient. The k L was observed not to have any significant
effect with the characteristic length of the promoter elements. The k L data were correlated in terms of Colburn j-factor
and Reynolds number.
In
the
present
work,
data
on
gas
holdup
were
obtained
in
a
bubble
column
with
inverted
cones
as
turbulent
promoter.
Water
was
chosen
as
liquid
phase
and
nitrogen
was
employed
as
gas
phase.
It
was
found
that
the
gas
holdup
increased
with
gas
velocity
and
decreased
with
liquid
velocity.
The
influence
of
rod
diameter
was
insignificant.
An
increase
in
cone
angle
resulted
in
an
increase
in
gas
holdup.
With
pitch
and
cone
angle,
the
gas
holdup
initially
increased
and
then
followed
a
decreasing
trend.
A
correlation
in
?g-Re
format
has
been
developed
from
regression
analysis.