Jordan University of Science & Technology

Chemical Engineering Department

CHE422-CHEMICAL INDUSTRIES

CHE 422 Project Report

Project title: Ammonia Production

Student names and numbers:

Roa'a Naseem ali bani mortada 113445

Sara Moutasim Mohammad 136449

Leen Sadi Abu Taleb 149546

Supervised by: Dr.Mohammad Alharahsheh

Date of submission:
 Introduction

The ammonia industry is a vital component of the global economy, serving as a key input for the

production of fertilizers, explosives, and other industrial chemicals. The process involves

nitrogen and hydrogen reacting over a catalyst to form ammonia, which is then purified and

.compressed for storage and transportation

The structure of ammonia compound (NH3) consists of one nitrogen atom bonded to three

hydrogen atoms, the nitrogen atom is in the center, with three single covalent bonds connecting it

to the hydrogen atoms. This arrangement gives ammonia a pyramidal shape, as shown in

:Figure1

Figure 1: Ammonia structure

Ammonia has been known for over 200 years, British chemist Joseph Priestley was the first to

isolate gaseous substances Ammonia in 1774. Its composition was determined by the French

chemist Claude Louis Berthollet in 1785. In 1898 Adolph Frank and Nikodem Caro discovered

.that N2 can be repaired by Calcium cyanamide made from calcium carbide

the modern ammonia Industry. Working with a student at the University of Karlsruhe, he

synthesized ammonia in the laboratory from N2 and H2

With the help of another German chemist called Carl Bosch, they developed the most important

industrial process for ammonia production in the first decade of the 20th century and it's called

.the Haber-Bosch process

The People’s Republic of China is the largest producer of ammonia today, accounting for 30% of

production, with the Russian Federation, the Middle East, the United States, the European Union

.and India accounting for a further 8-10% each

Ammonia is a colorless gas with a pungent odor that is widely used in the production of liquid

fertilizer solutions which consist of ammonia, ammonium nitrate, and aqua ammonia. It is also

used by the fertilizer industry to produce ammonium and nitrate salts. Another ammonia is used

.in refrigeration systems and as a cleaning agent

Raw materials:

According to the International Ammonia Energy Association, about 200m million tons of

ammonia is produced per year, however, 98% of the raw materials come from fossil fuels.

 The primary sources for obtaining the raw materials for ammonia production are as

follows:

1. Nitrogen (N2):
- Air: Nitrogen is extracted from the air through an air separation unit (ASU). Air contains

approximately 78% nitrogen, making it a readily available source.

2. Hydrogen (H2):
- Natural Gas: Hydrogen is often produced from natural gas through a process called steam

methane reforming (SMR). Natural gas is a hydrocarbon rich in methane, which can be

converted into hydrogen.

In the case of hydrogen production from natural gas, the steps include:

 Steam Methane Reforming: Natural gas is reacted with steam to produce hydrogen and

carbon dioxide.

 Water-Gas Shift Reaction: The carbon monoxide produced in SMR is further reacted

with steam to increase the hydrogen content and produce more CO2.

It's important to note that the source of hydrogen can vary, and alternative methods for hydrogen

production, such as electrolysis of water, can be used to obtain hydrogen from water sources.

However, natural gas-based hydrogen production is one of the most common methods in

ammonia synthesis.
  In addition to nitrogen and hydrogen, the production of ammonia may require a few other

raw materials and resources:

1. Catalysts: The Haber-Bosch process, which is used to synthesize ammonia from nitrogen and

hydrogen, often employs catalysts. Iron-based catalysts, such as iron oxide (Fe3O4), are

commonly used to facilitate the ammonia synthesis reaction.

2. Energy Source: Ammonia production typically requires a source of energy to provide the high

temperatures and pressures needed for the chemical reactions. Natural gas, for instance, can

serve as an energy source to heat the reactors and provide the necessary energy for the process.

3. Water: Water is essential for the production of ammonia, as it's a reactant in some of the

chemical reactions, especially in the water-gas shift reaction during hydrogen production.

4. Air and Oxygen: Air, which contains nitrogen, is used as a source of nitrogen in the air

separation unit (ASU). Oxygen from the air may also be used as an oxidant in some hydrogen

production methods.

5. Cooling Water: Ammonia synthesis reactors generate a significant amount of heat, and

cooling water is often required to maintain the appropriate temperature and prevent overheating

of equipment.

These raw materials and resources are essential for the ammonia production process, and their

availability and efficient utilization are critical to the overall production of ammonia.

The raw materials for the Haber process are Natural gas, air and water. In the first stage, Natural

gas (which is mostly methane) is reacted with steam to produce carbon dioxide and hydrogen. To

speed up the reaction, a catalyst is used. A high temperature and a high pressure also speed up

the reaction.
In the second stage, some of the hydrogen from the first stage is burnt in air. The oxygen in the

air reacts with the hydrogen to make steam. The reason for this second stage is to remove the

oxygen from the air to leave nitrogen behind. It also makes a lot of the heat needed in the Haber

process.

In the third stage, hydrogen from the first stage is mixed with nitrogen from the second stage.

The two gases are put under high temperature and high pressure. Usually 400°C and 150–300

atmospheres of pressure are used. Iron is also added as a catalyst. Some of the gases are

converted to ammonia. The ammonia is cooled to turn it into a liquid. The liquid ammonia is

then run off from the gases. The unconverted gases are then recycled to have another chance of

reacting.
Main reactions:

The reaction takes place in the presence of an iron catalyst at high temperature (450-500 ℃) and

high pressure (150-250 bar).

This is an exothermic reaction, it releases energy so that the sum of the enthalpies of N ₂ and H ₂

(the reactants) is greater than the enthalpy of NH3 (the products).

N2 (g) + 3H2 (g) 2NH₂ (g)

ΔH = -92 kj/mol

(This is a reversible reaction)

The reaction is effected by temperature, pressure and catalyst on the composition of the

equilibrium mixture, the rate of the reaction and the economics of the process. The catalyst is

actually slightly more complicated than pure iron. It has potassium hydroxide added to it as a

promoter - a substance that increases its efficiency.

The manufacturing of ammonia involves several steps. Here is a general overview of the process:

1. Feedstock Preparation: The primary feedstock for ammonia production is natural gas, although

other sources such as coal or oil can also be used. Natural gas is processed to remove impurities

like sulfur compounds and carbon dioxide.

2. Steam Reforming: The processed natural gas is mixed with steam and passed through a

reforming furnace. In the furnace, the natural gas reacts with steam at high temperatures

(typically around 850-1000°C) and over a catalyst to produce a mixture of hydrogen and carbon

monoxide called synthesis gas or syngas.

3. Shift Conversion: The syngas produced in the reforming step contains carbon monoxide,

which needs to be converted to carbon dioxide. This is done through the shift conversion

process, where the syngas is reacted with steam over a catalyst at high temperatures (around 350-

450°C) to convert the carbon monoxide to carbon dioxide.

4. Carbon Dioxide Removal: The carbon dioxide is removed from the shift conversion gas using

techniques like absorption or adsorption. This step helps improve the efficiency of the

subsequent ammonia synthesis process.

5. Ammonia Synthesis: The purified gas from the previous steps is now ready for ammonia

synthesis. It involves the reaction of hydrogen and nitrogen in the presence of a catalyst
(typically an iron or ruthenium-based catalyst) under high pressure (around 100-250 bar) and

moderate temperatures (around 350-450°C). This reaction produces ammonia gas.

6. Ammonia Separation: The ammonia gas is cooled and compressed to condense it into a liquid

form. This liquid is then separated from unreacted gases and impurities using distillation or other

separation techniques.

7. Product Storage and Distribution: The separated ammonia is stored, and depending on the

intended use, it can either be directly used in various industrial applications or further processed

into different forms like ammonia fertilizer.

The chosen numbers for temperature, pressure and conversion are roughly in the middle of the
ranges in the literature.

Block flow Diagram (PFD)

Figure 1: Ammonia block flow diagram (BFD)

The block flow diagram for gas-phase ammonia production is shown in the figure below .it
displays the input raw material, the finished product and the main equipment used in the process.
Process Flow Diagram (PFD)

Figure 2: Process Flow Diagram For gas-phase ammonia production (PFD)

The following figure describes what Visio is all about:" Visio is software for drawing a variety

of diagrams, include flowchart, org charts, building plans, data flow diagrams, process flow

diagram and many more. Thus, simulation of an entire chemical process, starting from the raw

material side down all the way to the final, finished product side and all the equipment used in

.the manufacture of ammonia

In Haber-Bosch process the reaction is carried out at a high pressure of around 200 (atm) and

temperature around 450°C, this helps to increase of ammonia .but the researchers found that

producing ammonia at low pressure and temperature have more advantages in energy efficiency,

increased safety by operating at lower pressure, the risk of equipment failure and accidental

release of toxic gases is significantly reduced, cost savings by using equipment less complex.

Additionally, high pressure conditions can be detrimental to the catalyst used in traditional

Haber-Bosch process, the catalyst may undergo deactivation due to mechanical pressure damage

or degradation from the reaction conditions, at low conditions can help prolong the catalyst's

lifespan and ensuring better efficiency.

The process of producing ammonia from N2 and H2 by reusing unreacted materials was studied.

The process is investigated at relatively low pressure (48 bar) and temperature (190°C). CSTR is

isothermally runs under equilibrium conditions .Using recycling, it was shown that a liquid

ammonia product with a purity of up to 99.3 wt% was achieved. Waste is reduced and can be

used as fuel. An economic analysis was also performed using Visio Process software.

At first, the feed stream containing H2, N2, and CO2 entering to compressor at room temperature

and 20 atm, then the pressure raising up to 48.5 bar, the output of compressor that is driven by

electric motor in stream (1) it mixed with the recycled stream mainly H 2, N2 at the same pressure

in stream (10), the combined fed to heat exchanger 1 in stream (2) to heated up the reaction at
temperature at 190℃ in stream (3),to inlet the CSTR reactor that is isothermally run at 190℃
3
m . under equilibrium conditions with pressure 48.5 bar and volume is set to 12

The following equilibrium reaction is assumed to take place in the CSTR reactor:

N2 (g) + 3H2 (g) 2NH₂ (g)

This reaction is exothermic where releases heat is during the process and to generate medium

pressure steam.

The outlet of the reactor in stream (4) is fed to the second heat exchanger to cool the reaction

products to 135℃ , the cooling takes place utilizing type 2 refrigeration (phase change

temperature of -40℃ to -35℃ ), the output of cooler sent to flash drum separator at

temperature -35℃ and 40 atm in steam (5), at the bottom in stream (6) the liquid comes out

containing CO2 and pure ammonia, at the top in stream(7) a tiny amount of the flash drum off

vapor is purged with a split containing unreacted H2, N2,and sent to the inlet of the second

compressor where its pressure is elevated to 48.5 bar in stream (9),the compressed recycled

stream is finally mixed with the compressed fresh feed prior to introduction to the reactor in

stream (10).
 References

1. https://www.aiche.org/resources/publications/cep/2016/september/introduction-ammonia-
production

2. https://www.iea.org/reports/ammonia-technology-roadmap

3. https://en.wikipedia.org/wiki/Haber_process

4. https://www.freefullpdf.com/search_gcse/?q=raw%20material%20of
%20ammonia#google_vignette&gsc.tab=0

5. https://homework.study.com/explanation/what-are-the-raw-materials-used-for-the-haber-
process.html

6. https://www.chemistryscl.com/advancedlevel/industry/ammonia/theory/main.html

7. https://byjus.com/question-answer/name-the-following-raw-materials-used-in-the-
preparation-of-ammonia/

8. https://www.google.jo/books/edition/Ammonia/xWz8CAAAQBAJ?
hl=ar&gbpv=1&dq=ammonia+industry+pdf&printsec=frontcover

9. "Perry's Chemical Engineers' Handbook" (8th Edition) edited by Robert H. Perry and
Don W. Green

10. "Industrial Chemical Process Design" by Douglas L. Erwin

12. https://studymind.co.uk/notes/conditions-of-the-haber-process/

13. https://www.researchgate.net/figure/The-process-flowsheet-for-gas-phase-ammonia-
production-with-recycling-of-unreacted-H2-and_fig1_329209539