This document describes the development and validation of a mathematical model for a radial flow ammonia converter. The model equations account for material and energy balances across the three catalyst beds. Comparison to plant data from Abu Qir Fertilizers Company showed good agreement between the model and actual performance. The model is useful for optimizing operating conditions, evaluating catalyst performance over time, and determining the effects of adding a fourth catalytic bed.
Most modern ammonia processes are based on steam-reforming of natural gas or naphtha.
The 3 main technology suppliers are Uhde (Uhde/JM Partnership), Topsoe & KBR.
The process steps are very similar in all cases.
Other suppliers are Linde (LAC) & Ammonia Casale.
This is great Presentation with 3D effects which is all about production of ammonia from natural gas.
I am damn sure you will be getting everything here searching for.
its better to download it and then run in powerpoint 2013.
This slides shows vocational training which i've done at ammonia-4 plant at GSFC LTD.
There are some tasks that given by our university that we have done here.
Most modern ammonia processes are based on steam-reforming of natural gas or naphtha.
The 3 main technology suppliers are Uhde (Uhde/JM Partnership), Topsoe & KBR.
The process steps are very similar in all cases.
Other suppliers are Linde (LAC) & Ammonia Casale.
This is great Presentation with 3D effects which is all about production of ammonia from natural gas.
I am damn sure you will be getting everything here searching for.
its better to download it and then run in powerpoint 2013.
This slides shows vocational training which i've done at ammonia-4 plant at GSFC LTD.
There are some tasks that given by our university that we have done here.
Introduction and Theoretical Aspects
Catalyst Reduction and Start-up
Normal Operation and Troubleshooting
Shutdown and Catalyst Discharge
Nickel Carbonyl Hazard
Modern Methanation Catalyst Requirements
Introduction High temperature shift Catalysts
Low temperature shift catalysts
Catalyst storage, handling, charging and discharging
Health and safety precautions
Reduction and start-up of high temperature shift catalysts
Operation of high temperature shift catalysts
Reduction and start-up of low temperature shift catalysts
Operation of low temperature shift catalysts
(HTS) High Temperature Shift Catalyst (VSG-F101) - Comprehensiev OverviewGerard B. Hawkins
The high temperature shift duty introduction and theory
HTS catalyst characteristics
developments over time
Typical HTS operational problems
Improved catalysts
VULCAN Series VSG-F101 Series
Summary
Calculation of an Ammonia Plant Energy Consumption: Gerard B. Hawkins
Calculation of an Ammonia Plant Energy Consumption:
Case Study: #06023300
Plant Note Book Series: PNBS-0602
CONTENTS
0 SCOPE
1 CALCULATION OF NATURAL GAS PROCESS FEED CONSUMPTION
2 CALCULATION OF NATURAL GAS PROCESS FUEL CONSUMPTION
3 CALCULATION OF NATURAL GAS CONSUMPTION FOR PILOT BURNERS OF FLARES
4 CALCULATION OF DEMIN. WATER FROM DEMIN. UNIT
5 CALCULATION OF DEMIN. WATER TO PACKAGE BOILERS
6 CALCULATION OF MP STEAM EXPORT
7 CALCULATION OF LP STEAM IMPORT
8 DETERMINATION OF ELECTRIC POWER CONSUMPTION
9 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT ISBL
10 ADJUSTMENT OF ELECTRIC POWER CONSUMPTION FOR TEST RUN CONDITIONS
11 CALCULATION OF AMMONIA SHARE IN MP STEAM CONSUMPTION IN UTILITIES
12 CALCULATION OF AMMONIA SHARE IN ELECTRIC POWER CONSUMPTION IN UTILITIES
13 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT OSBL
14 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT
Why have a Secondary Reformer ?
Need nitrogen to make ammonia
Wish to make primary as small as possible
Wish to minimise methane slip since methane is an inert in the ammonia synthesis loop
Other methods of achieving this
Braun Purifier process
Can address all these with an air blown secondary
Equilibrium Effects
- Methane Steam
- Water Gas Shift
Relationship of Kp to Temperature
Relationship of WGS Kp to Temperature
Effect of Temperature on Methane Slip
Approach to Equilibrium
Reaction Path and Equilibrium
Effect of Pressure Increase
Operating Parameters
- Pressure
- Temperature
- Feed Rate
- Steam to Carbon
Effect of Exit Temperature Spread
Useful Tools
Calculating ATM
VULCAN Series VSG-Z101 Primary Reforming
Initial Catalyst Reduction
Activating (reducing) the catalyst involves changing the nickel oxide to nickel, represented by:
NiO + H2 <==========> Ni + H2O
Natural gas is typically used as the hydrogen source. When it is, the catalyst reduction and putting the reformer on-line are accompanied in the same step.
1. Introduction reasons for purification, types of poisons, and typical systems
2. Hydrogenation
3. Dechlorination
4. Sulfur Removal
5. Purification system start-up and shut-down
Purpose
Key to good performance
Problem Areas
Catalysts, heat shields and plant up-rates
Burner Guns
Development of High Intensity Ring Burner
Case Studies
Conclusions
Influence of Operating Variables on Functional Parameters of Ammonia Synthesi...Premier Publishers
The synthesis of ammonia involves several parameters that require appropriate control measures. Hence, this study investigated the effects of operating temperature and pressure on size, space velocity, mean residence time and heat generated per unit reactor volume at capacity of 430,000 tons of ammonia production per year. The analysis was performed at temperature and pressure ranges of 673 – 773 K and 150 – 300 atm. At constant conversion, the volume and mean residence time decreased with increase in operating temperature and pressure, while space velocity and heat generated per unit reactor volume increased with increasing temperature and pressure. For instance, from 698 – 773 K and at constant pressure of 250 atm and 0.32 conversion, volume and mean residence time decreased from 3.717 to 0.501 m3 and 7.01 x 10-5 to 9.46 x 10-6 hr, while space velocity and heat generated per unit reactor volume increased from 1.698 x 104 to 1.259 x 105 hr-1 and 1.40 x 107 to 1.57 x 108 kJ/hr.m3 respectively. The temperature and pressure ranges may be realistic, but 698 K and 250 atm is considered for the designed capacity based on the process economics, size and heat requirement.
Introduction and Theoretical Aspects
Catalyst Reduction and Start-up
Normal Operation and Troubleshooting
Shutdown and Catalyst Discharge
Nickel Carbonyl Hazard
Modern Methanation Catalyst Requirements
Introduction High temperature shift Catalysts
Low temperature shift catalysts
Catalyst storage, handling, charging and discharging
Health and safety precautions
Reduction and start-up of high temperature shift catalysts
Operation of high temperature shift catalysts
Reduction and start-up of low temperature shift catalysts
Operation of low temperature shift catalysts
(HTS) High Temperature Shift Catalyst (VSG-F101) - Comprehensiev OverviewGerard B. Hawkins
The high temperature shift duty introduction and theory
HTS catalyst characteristics
developments over time
Typical HTS operational problems
Improved catalysts
VULCAN Series VSG-F101 Series
Summary
Calculation of an Ammonia Plant Energy Consumption: Gerard B. Hawkins
Calculation of an Ammonia Plant Energy Consumption:
Case Study: #06023300
Plant Note Book Series: PNBS-0602
CONTENTS
0 SCOPE
1 CALCULATION OF NATURAL GAS PROCESS FEED CONSUMPTION
2 CALCULATION OF NATURAL GAS PROCESS FUEL CONSUMPTION
3 CALCULATION OF NATURAL GAS CONSUMPTION FOR PILOT BURNERS OF FLARES
4 CALCULATION OF DEMIN. WATER FROM DEMIN. UNIT
5 CALCULATION OF DEMIN. WATER TO PACKAGE BOILERS
6 CALCULATION OF MP STEAM EXPORT
7 CALCULATION OF LP STEAM IMPORT
8 DETERMINATION OF ELECTRIC POWER CONSUMPTION
9 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT ISBL
10 ADJUSTMENT OF ELECTRIC POWER CONSUMPTION FOR TEST RUN CONDITIONS
11 CALCULATION OF AMMONIA SHARE IN MP STEAM CONSUMPTION IN UTILITIES
12 CALCULATION OF AMMONIA SHARE IN ELECTRIC POWER CONSUMPTION IN UTILITIES
13 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT OSBL
14 DETERMINATION OF THE TOTAL ENERGY CONSUMPTION OF THE AMMONIA PLANT
Why have a Secondary Reformer ?
Need nitrogen to make ammonia
Wish to make primary as small as possible
Wish to minimise methane slip since methane is an inert in the ammonia synthesis loop
Other methods of achieving this
Braun Purifier process
Can address all these with an air blown secondary
Equilibrium Effects
- Methane Steam
- Water Gas Shift
Relationship of Kp to Temperature
Relationship of WGS Kp to Temperature
Effect of Temperature on Methane Slip
Approach to Equilibrium
Reaction Path and Equilibrium
Effect of Pressure Increase
Operating Parameters
- Pressure
- Temperature
- Feed Rate
- Steam to Carbon
Effect of Exit Temperature Spread
Useful Tools
Calculating ATM
VULCAN Series VSG-Z101 Primary Reforming
Initial Catalyst Reduction
Activating (reducing) the catalyst involves changing the nickel oxide to nickel, represented by:
NiO + H2 <==========> Ni + H2O
Natural gas is typically used as the hydrogen source. When it is, the catalyst reduction and putting the reformer on-line are accompanied in the same step.
1. Introduction reasons for purification, types of poisons, and typical systems
2. Hydrogenation
3. Dechlorination
4. Sulfur Removal
5. Purification system start-up and shut-down
Purpose
Key to good performance
Problem Areas
Catalysts, heat shields and plant up-rates
Burner Guns
Development of High Intensity Ring Burner
Case Studies
Conclusions
Influence of Operating Variables on Functional Parameters of Ammonia Synthesi...Premier Publishers
The synthesis of ammonia involves several parameters that require appropriate control measures. Hence, this study investigated the effects of operating temperature and pressure on size, space velocity, mean residence time and heat generated per unit reactor volume at capacity of 430,000 tons of ammonia production per year. The analysis was performed at temperature and pressure ranges of 673 – 773 K and 150 – 300 atm. At constant conversion, the volume and mean residence time decreased with increase in operating temperature and pressure, while space velocity and heat generated per unit reactor volume increased with increasing temperature and pressure. For instance, from 698 – 773 K and at constant pressure of 250 atm and 0.32 conversion, volume and mean residence time decreased from 3.717 to 0.501 m3 and 7.01 x 10-5 to 9.46 x 10-6 hr, while space velocity and heat generated per unit reactor volume increased from 1.698 x 104 to 1.259 x 105 hr-1 and 1.40 x 107 to 1.57 x 108 kJ/hr.m3 respectively. The temperature and pressure ranges may be realistic, but 698 K and 250 atm is considered for the designed capacity based on the process economics, size and heat requirement.
Packed Bed Reactor for Catalytic Cracking of Plasma Pyrolyzed Gasijsrd.com
Packed bed reactors play vital role in chemical industries for obtaining valuable product, like steam reforming of natural gas, ammonia synthesis, sulphuric acid production, methanol synthesis, methanol oxidation, butadiene production, styrene production. It is not only used for production but also used in separation process like adsorption, distillation and stripping section. Packed bed reactors are work horse of the chemical and petroleum industries. Its low cost, and simplicity makes it first choice to any chemical processes. In our experimental work vacuum residue is used as a feed which is pyrolyzed in the primary chamber with the help of plasma into hydrogen and hydrocarbon gases which is feed stream to the Ni catalyst containing packed bed reactor called catalytic cracker. Ni loading in the catalyst about 70 % is used to crack or decompose lower molecular hydrocarbon in to hydrogen to maximize the energy content per mass flow of gas steam and also to minimize the carbon dioxide equivalent gases at outlet of the reactor. Since cracking is surface phenomena so the catalyst play important role in designing of reactor shape. Parallel Catalytic packed bed with regeneration and deactivation can be used for commercial production of clean fuel.
Cfd investigation of cyclic mode operation in a heat recovery steam generatorR&R Consult
A 250MWe HRSG plant experienced tube failures after the operation changed to daily load shift. The CFD investigation clearly showed the issue, the flow correction devices were only designed for base load conditions and at part load variation on +-200% was seen in flow distribution upstream the first tube section.
More info at www.R-R-Consult.dk & www.tetra-eng.com
Experimental investigate to obtain the effectiveness of regenerator using Air.IJESFT
The regenerator is a kind of heat exchanger that provides a way to get the gas to the low temperature with as much potential work (cooling power) as possible without carrying a lot of heat with it. It doesn’t put heat in or out of the system but it absorbs heat from the gas on one part of the pressure cycle and returns heat to the gas on the other part.
More recent applications of regenerators in cryogenic systems can be found in small cryogenic refrigerators (cryocoolers). Systems such as the Stirling Gifford-McMahon, pulse tube, Solvay, Vuilleumier and magnetic cycle refrigerators all use either a static or rotary regenerator. In fact, the success these coolers have achieved is directly related to the characteristics of compact size and efficiency of the regenerator.
Regenerator effectiveness of 99% results in 21% loss of refrigeration effect, similarly regenerator effectiveness of 98% results in 42% loss of refrigeration effect, with refrigeration effectiveness of 95.238% the loss of refrigeration is 100%. i.e. no net cooling is produced.
In cryogenic applications the regenerator is typically made up of 100 to 500 meshes SS 304, Phosphorous bronze screens or small lead spheres (150 to 300 micro meters) are used, that are tightly packed together and held in place on either end in the same manner.
To develop experimental setup at our laboratory level by using air as working fluid and find out the effectiveness of various regenerative materials is basic goal of this work.
Catalytic Reforming technology - Infographics
IFP Fixed-bed Semi-regenerative Unit Revamps, Troubleshooting
IFP (CCR) Technology Optimization
In trying to determine the potential benefits from revamping a Fixed-bed Semi-Regenerative catalytic reformer, a refiner must evaluate several areas of operation:
— What is the unit operating objective?
— What degrees of freedom are available for revamp /optimization?
— Can refinery margins, and the discretionary capital budgeting program support the revamp / optimization?
Refiners must select the catalytic reformer operating point that will maximize profit within the following:
1) the mechanical constraints of the unit and
2) the short term unit operating objectives.
projects that improve operating profit are compared with the required capital investment.
This is done using discounted cash flow, or one of a number of other capital budgeting analysis tools, and those projects with the greatest return are put at the top of the capital budget list.
INTRODUCTION
COMPARISION BETWEEN FIXED BED VS FLUIDISED BED REACTOR
SELECTION CRITERIA FOR CATALYST REACTOR
DESIGN OF CATALYST REACTOR
DESIGN OF DEACTIVATION OF CATALYST
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
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Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Courier management system project report.pdfKamal Acharya
It is now-a-days very important for the people to send or receive articles like imported furniture, electronic items, gifts, business goods and the like. People depend vastly on different transport systems which mostly use the manual way of receiving and delivering the articles. There is no way to track the articles till they are received and there is no way to let the customer know what happened in transit, once he booked some articles. In such a situation, we need a system which completely computerizes the cargo activities including time to time tracking of the articles sent. This need is fulfilled by Courier Management System software which is online software for the cargo management people that enables them to receive the goods from a source and send them to a required destination and track their status from time to time.
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
When a customer search for a automobile, if the automobile is available, they will be taken to a page that shows the details of the automobile including automobile name, automobile ID, quantity, price etc. “Automobile Management System” is useful for maintaining automobiles, customers effectively and hence helps for establishing good relation between customer and automobile organization. It contains various customized modules for effectively maintaining automobiles and stock information accurately and safely.
When the automobile is sold to the customer, stock will be reduced automatically. When a new purchase is made, stock will be increased automatically. While selecting automobiles for sale, the proposed software will automatically check for total number of available stock of that particular item, if the total stock of that particular item is less than 5, software will notify the user to purchase the particular item.
Also when the user tries to sale items which are not in stock, the system will prompt the user that the stock is not enough. Customers of this system can search for a automobile; can purchase a automobile easily by selecting fast. On the other hand the stock of automobiles can be maintained perfectly by the automobile shop manager overcoming the drawbacks of existing system.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Final project report on grocery store management system..pdf
Ammonia converter
1. 1 Evaluationperformanceof a radialflowammonia converter, Dr.M.T.ElTohfa
ABU QIR FERTILIZERS CO.
Alexandria - Egypt
Dr. Mohamed tarek El-Tohfa
AmmoniaProcessDept.Manager
2. 2 Evaluationperformanceof a radialflowammonia converter, Dr.M.T.ElTohfa
Introduction
Ammonia converter configuration
Performance of a radial flow ammonia converter
Ammonia converter modelling, simulation and optimization
Model development and verification
Ammonia converter catalyst Evaluation
Addition of fourth bed as a booster converter
Summary
3. 3 Evaluationperformanceof a radialflowammonia converter, Dr.M.T.ElTohfa
Egypt
Located at the cost of
Abu-Qir bay
20 Km east
Alexandria – Egypt
1975
Abu Qir fertilizers company is one of the
largest nitrogen fertilizers production
complexes in the Middle East. It comprises
three plants producing 6000 tons daily.
4. 4 Evaluationperformanceof a radialflowammonia converter, Dr.M.T.ElTohfa
1979 1990 1991 1998 2005 2006
Abu Qir I Abu Qir II
Abu Qir IIIMarine Line UAN
NPK
5. 5 Evaluationperformanceof a radialflowammonia converter, Dr.M.T.ElTohfa
ABU QIR plant III was commissioned in October
1998, it consists of two main plants, ammonia plant
with capacity 1200 ton/day and Urea plant with
capacity 1750 ton/day.
8. 8 Evaluationperformanceof a radialflowammonia converter, Dr.M.T.ElTohfa
Features of UHDE 3-bed radial flow ammonia
converters:-
low pressure drop.
small catalyst size
maximum conversion rate
optimum temperature control
no reduction of ammonia concentration
Three radial flow type catalyst beds
Indirect cooling by heat exchangers
The catalyst type BASF S6-10/S6-10 red, is a
magnetite (Fe3O4) catalyst, Size (1.5-3) mm and
the operating temperature range is 350 –520°C.
9. 9 Evaluationperformanceof a radialflowammonia converter, Dr.M.T.ElTohfa
Two differential equations describe mathematically the steady state
behavior of the ammonia converter:-
I. Concentration-Position relationship for transformation of
the reactants to products (Conversion profile).
II. Temperature-Position behavior of the reacting synthesis gas,
the catalyst, and vessel internals (Temperature profile).
The derivation of the model equations on the basis of bed
radius (dr) enables us to follow-up the temperature
distribution inside the catalyst bed more accurate ,
especially the temperature transmitters passes inside the
catalyst bed.
10. 10 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
Material balance:
Based on nitrogen conversion:
A
F
R
dr
dX
No
NHN
2
32
2
1
η = 1 : Effectiveness factor (diffusion resistance)
: The initial molar flow rate of nitrogen, kmol/hr.
A : Surface area of catalyst bed, m2
r : Radius of catalyst bed, m
RNH3 : Reaction rate, kmol/m3.hr
XN2 : Fractional conversion of nitrogen
2NoF
Where:
11. 11 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
Energy balance:
p
NHr
ρuc
ηRΔH
dr
dT 3
2
ipp Ycc imix
(Redlich-Kwong thermodynamic relation). : Gas Density, kg/m
ΔHr : Heat of reaction, kJ/kmol.
cp : Specific heat of reacting gas mixture, kJ/kg. K
u : Fluid velocity, m/hr.
RNH3 : Reaction rate, kmol/m3.hr
: Effectiveness factor
T : Temperature, K
r : Radius of catalyst bed, m
Where:
12. 12 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
Reaction Rate:
α1
3
H2
2
NH
α
2
NH
3
H
2
2
a2NH
a
a
a
a
aNKkβR 3
3
2
3
Where:
α (Constant) = 0.5-0.75
K2 Rate constant for reverse reaction
Ka Equilibrium constant
ai Activity of component i
β Catalyst activity coefficient
(Modified Temkin equation)
13. 13 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
Reaction Rate Constant K2
K2 = K0 exp (-E/RT)
K0 Arrhenius coefficient
E Activation energy
R Gas constant
Equilibrium Constant Ka
6899.2
6.2001
10848863.110519265.5log691122.2log 275
1010
T
TTTKa
Heat of reaction:
0.14215P51.21P101.928108.3395T
TP104.455214.35953.1619P6.329.3T100.11625
T100.03356T100.349967.2949T91840ΔH
632
349
3522
r
14. 14 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
r = ro
XN2 = 0
T = Ti
The sets of model differential equations were solved in
MATLAB employing 4th order Runge Kutta approach with
initial conditions:
The temperature and conversion profiles for the three beds obtained
from the present developed model were compared to operating data
of a radial flow ammonia converter in Abu-Qir plant III in order to
validate these results and estimate the percent deviation.
25. 25 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
Effect of
inlet flow
rates
Effect of
inert content
Effect of
operating
Pressure
Effect of
inlet
ammonia
conc.
35. 35 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
0
0.2
0.4
0.6
0.8
1
1.2
0 2 4 6 8 10 12 14 16 18 20
Catalystactivitycoefficient,β
time, years
36. 36 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
Fourth bed length Vs Ammonia conversion
37. 37 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
Fourth bed length Vs Ammonia production
38. 38 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
A successful model was developed to represent the performance of a
radial flow ammonia converter in ammonia plant III at Abu-Qir
Fertilizers Company.
The model was verified and the results show that the calculated
values are in very good agreement with the plant data.
The model can predict the first bed outlet temperature which is
considered the highest temperature in the reactor (can't be practically
measured).
The model is utilized to calculate the catalyst activity coefficient (β)
which is used for the catalyst performance evaluation with time, and
compare between different types of catalysts.
39. 39 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
Steady state simulator is used as a guide to adjust the synthesis loop
operating conditions at different operation modes, in both normal and
emergency operation to improve the ammonia converter performance.
The model is utilized to determine the optimum inlet bed temperature
to obtain higher production rate and maximize ammonia converter
efficiency.
Addition of a new catalytic fourth bed (Booster Converter) was
studied to increase the conversion per pass of the ammonia synthesis
reaction, increase ammonia production rate and save energy. The
present developed model was utilized to figure out the length of the
fourth bed with the ammonia conversion and ammonia production.
40. 40 Evaluationperformance of a radialflowammonia converter, Dr.M.T.ElTohfa
Dr. Mohamed tarek El-Tohfa
Dr.Eng.mtarek@gmail.com
AmmoniaPlantIII
AmmoniaProcessDepartmentManager