SIMULATION OF CARBON DIOXIDE CAPTURE
BATCH 2018-19
Group Members:
Name:
Seat No
Ammar Ullah Khan
18062
Ariba Khan
18047
Baneen Fatima
18060
Umair Khalid
18047
DEPARTMENT OF CHEMICAL ENGINEERING
NED UNIVERSITY OF ENGINEERING AND TECHNOLOGY
i
Table of Contents
Type chapter title (level 1) ........................................................................................................ 1
Type chapter title (level 2) ..................................................................................................... 2
Type chapter title (level 3) ................................................................................................. 3
Type chapter title (level 1) ........................................................................................................ 4
Type chapter title (level 2) ..................................................................................................... 5
Type chapter title (level 3) ................................................................................................. 6
1. ABSTRACT
2. INTRODUCTION
2.1 PROBLEM STATEMENT
Carbon dioxide is a one of the primary greenhouse gases (GHG) that plays a
significant role in global warming. It is naturally prevalent in the atmosphere but
human activities have increased the emissions over the years [1]. Coal and gas fired
power plants are the major contributors of CO2 emissions closely followed by cement,
steel and aluminum industries. Carbon capture and storage (CCS) is the most feasible
technique to achieve a green environment. Post combustion flue gases can be treated
with chemical solvents to remove CO2 before they are released into the atmosphere.
The separated CO2 can be pumped underground or used in various processes such as
enhanced oil recovery (EOR) [2].
2.2 Objectives
The prime objective of this study is simulation and optimization of carbon dioxide
capture than can be applicable for industries. Aspen HYSYS will be used to model
and simulate the CO2 capture technology.
3. Literature Review
Worrada Nookuea, Jie Yang and Xinhai Yue [3] measured and reported
thermo-physical properties (like viscosity and density) for different
compositions of ionic and alkanolamine solutions mixtures. The aim of the
study was to improve the absorption of CO2 by enhancing the absorbent's
capacity and tendency to capture CO2. Different compositions by weight
percentage of methyldiethanolamine MDEA and [Bmim][BF4] at different
temperatures were prepared. The data was useful in construction of
absorber/desorber and power consumption of pump and total heat transfer by
exchanger and generating a correlation for solvent's viscosity predictions.
Deviation in actual and measured viscosities were found to be 4.9%(AAD).
The trend shows an increase in viscosity when concentration of [Bmim][BF
4] is increased but a decrease is observed when the temperature is increased.
The effect of temperature is more prominent on low temperature ranges.
S. Moioli a*, L. A. Pellegrini, S. Gamba [4] performed a simulation on
ASPEN Plus® and modeled it on theories of Lewis and Whitman and that of
Eddy Diffusivity theory. They were capturing CO2 from exhaust gas using
aqueous solution of Monoethanolamine (MEA) as an absorbent. Their Model
was found to be removing CO2 with an aqueous solution of
Monoethanolamine 30% w/w giving a "CO2 removal profile" and a
"Temperature Profile". When simulated with a pilot plant's experimental data.
Their results were closed to that of experimental one but the Rate of
absorption was slower.
Schäffer , K. Brechtel, and G. Scheffknecht [5] investigated the effects of
differently concentrated aqueous solutions of monoethanolamine (MEA) and
Triethylenetetramine ( TETA ) on CO2 capture from flue gases emitted from
power plants. Synthetic gas was used with CO2 concentration 15 volume% and
O2 5 volume% . The temperature range set for equilibrium concentration of
CO2 loading is between 30 and 95ᵒC. At low concentrations, bicarbonate
formation produce high equilibrium loading and high water-amine ratio and at
high temperature, carbamate destabilization caused decreased loadings. MEA
and TETA give similar value of mass cyclic capacities. It was observed that
TETA is an alternative to MEA since it has high reaction kinetics and same
CO2.
4. METHODOLOGY/ SIMULATION
The carbon capture technology is modeled and simulated in Aspen HYSYS. Methyl
diethanolamine (MDEAmine) is used as a the solvent. Acid gas chemical solvents
fluid package is selected.
Flue gas and solvent feed parameters are given in Table. The process is developed to
capture 81% of the carbon dioxide from flue gas. The compositions for both of the
streams are also shown below in Table
PARAMETERS
FLUE GAS
SOLVENT
Temperature
65C
25C
Pressure
1.5 bar
1.2 bar
Flowrate
1000kg/h
3800kg/hr
FLUE GAS COMPONENTS
COMPOSITION (mol%)
Nitrogen
70
Water
15
Carbon Dioxide
10
Oxygen
5
SOLVENT COMPONENTS
COMPOSITION (wt%)
MDEA
75
Water
25
Absorber and a distillation column (used as a stripper) are considered the two major
operation blocks. The Absorber has no packing. A reboiler and a total condenser are
attached to the stripping column. The rest of the specifications are tabulated in Table
A pump with efficiency of 75% is employed.
SPECIFICATIONS
ABSORBER
STRIPPER
Number of stages
50
10
Temperature
Pressure
Packing height
Top Pressure: 1.2 bar
Bottom Pressure: 1.5 bar
None
1 bar
None
5. RESULT AND DISCUSSION