Mass and Energy Balance

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Ammonia Plant Proposal|
Ammonia Production Via Steam Reforming|
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Group I: Matthew Lincoln, Jonathan Willis, Kyle Palfreeman, Suet Syn Siew, Sandra George, Muhammad Nawaz, Dean Carney, Steve Baker| 11/23/2012|

Contents
Abstract2
What is Ammonia3
Application and Uses3
Market Trends3
Processes4
Partial Oxidation4
Hazards and Environmental Impact4
Electrolysis5
Steam Reforming6
Gas purification6
Desulphurisation6
The Process6
Justification7
Mass Balance7
Cp Values7
Energy Balance7
Raw Material Costs7
Pay Back Time7
Conclusion7
Appendices8
Reference 1: Partial Oxidation Flow Sheet8
Reference 2: Steam Reforming Flow Sheet0

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Abstract
The objective is to produce a proposal for a chemical process plant which will be able to produce 550,000 tonne/year ammonia using LPG as the raw material. Different processes where researched and then finally one was picked, steam reforming. This was decided to be the most viable and cost effective process using the raw materials we had available. The report explains in detail how the process works and all aspects of how the plant will work including the mass and energy balance across the plant.

What is Ammonia
Ammonia (NH3) is a stable compound and is used as a starting material for the manufacture of many important nitrogen compounds and can also be directly used as fertilisers. It is produced by reacting hydrogen and nitrogen. It is a colourless gas with a sharp odour. The boiling point is -33.35oC and its freezing point is -77.7oC.1 Care must be taken when handling ammonia as can cause deep burns in the skin; irritation in the eyes and nose and when inhaled can cause coughing, sore throat and headache.2 There are different methods for the manufacture of ammonia. The three main methods are steam reforming, partial oxidation and electrolysis. Application and Uses

Ammonia is a widely used chemical in different types of industries. One of the main user of ammonia is the agricultural industries for fertilisers. Around 80% of ammonia produced is for fertilisers such as urea, ammonium sulphate and ammonium nitrate.3 It is also used as a building block for nitrogen containing compounds like nitric acid (HNO3). It is also used in the fibres and plastics industry for the production of acrylonitrile, melamine etc., and manufacture of explosives. Ammonia is also used in water treatment such as pH control and also in combination with chlorine to purify industrial and municipal water supplies. Less commonly uses include as a refrigerant in compression and absorption systems, manufacture of household ammonia, in the food and beverage industry 4.

Figure 1: Pie chart showing the uses of Ammonia.

Market Trends
Globally ammonia prices have been headed up due the large demand of fertilisers that are needed in the crop production to obtain high yield6. The current selling price of ammonia in Europe goes up to $600 per tonne7.

Figure 2: Shows the global demand for Ammonia (D.a.NH3- Direct application of Ammonia) As we can see from the chart the trend of ammonia demand globally is upward. It is said that the global ammonia market is to generate revenues of approx. US$102 billion in 2019. As there is continous growth in population in the developing countries the likely to cause demand for foodstuffs are to increase even further. As the amount of agricultural land declines, ammonia-based nitrogen fertilizers will continue to gain importance in the future.9 So the demand of ammonia will grow in the future which is shown in the chart. Processes

There are many different processes involved in the ammonia production. The most common processes for ammonia are partial oxidation, steam reforming and electrolysis. From these 3 processes the best process route is then selected and that process would be most economical and that meetes the design brief. Partial Oxidation

Partial oxidation involves the reaction of...
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