BC Insight - Nitrogen+Syngas, Sulphur, Fertilizer International
Login
BCInsight Ltd
China Works
Black Prince Road
London, SE1 7SJ
United Kingdom
Tel: +44 (0)20 7793 2567
Fax: +44 (0)20 7793 2577

Publication > Issue > Articles

Non-fertilizer uses of ammonia

Summary

Although demand for ammonia is predominantly based around nitrogen as a plant nutrient, it is also an important and versatile industrial chemical. Nitrogen & Methanol looks at the various uses to which it is put, and the prospects for future demand in this sector.

Abstract

Of the approximately 125m tonnes of ammonia that are produced worldwide every year, around 85% is employed for agricultural use, either directly applied to fields, or applied after it has been converted either to urea, ammonium sulphate or nitric acid, and thence to ammonium nitrate, CAN, UAN and NPK compounds.

Of the remaining 20m tonnes or so, some ammonia is used directly, as a refrigerant or in paper and metallurgical uses. However, most of the remainder is used indirectly, via various intermediate compounds, in chemicals production. Since the Haber-Bosch process is currently the only economical way of ‘fixing’ atmospheric nitrogen, virtually every nitrogen atom which is used in chemical production passes through an ammonia stage on its way to its final destination, to produce chemicals for explosives, fibre, or plastics use, including nitrobenzene, acrylonitrile, isocyanates, adipic acid, caprolactam, nitroparaffin, and potassium and sodium nitrates.

Add to basket


The chemical bearings of the ammonia process

Summary

Catalysts have to be designed as carefully as any piece of equipment in an ammonia plant. In spite of the excellent quality of today's commercial catalysts, the developers are on a constant quest for improvement.

Abstract

Five out of the six main process steps in a modern gas-based ammonia plant require a catalyst, some more than one. They are:

  • Feedstock desulphurization
  • Steam reforming
  • Carbon monoxide shift conversion
  • Methanation
  • Ammonia synthesis

Some process schemes do not include a methanation step.

The design of the catalyst is at least as critical as the design of any other feature of the process, and careful control of the process conditions under which each of them operates is vital to prevent damage. None of the catalysts used in an ammonia plant is cheap, but any mistake which leads to physical or chemical damage of any of them is likely to be far more costly than just a replacement charge of catalyst. At best it will impair the energy-efficiency and productive capacity of the plant. In more serious cases it may force a complete shut-down or even cause serious damage to the hardware of the plant.

Against the background of a very competitive market, a handful of specialist companies have striven over the years to design catalysts that combine high activity, physical strength and ruggedness, low resistance to gas flow, even packing characteristics, and prolonged chemical and physical stability. That entails some of the most intricate design work and consummate skill in translating the design into reality. The truly excellent quality of the products on the market today is testament to the years of diligent and painstaking work put in by their developers.

Add to basket


A visit to Tjelbergodden

Summary

Nitrogen & Methanol visited Europe's newest methanol plant, and one of the new breed of 'remote' facilities designed to utilise associated gas from oil production in order to avoid flaring.

Abstract

Tjelbergodden is Europe’s newest and largest methanol plant. Operated by Norwegian state oil and gas company Statoil, it is also the northernmost methanol plant in the world. The plant is located on the shore of a fjord to the west of Trondheim. It is a rugged and starkly beautiful location, and, while the local weather is not as good as Trinidad’s (!), fortunately the Gulf Stream keeps the sea mostly ice-free, while offshore islands shelter the site from the worst of the elements. Trondheim Fjord is deep enough to handle large draft vessels, and although local methanol consumption is minimal, Rotterdam is only a 48 hour sail away.

The plant, costed at $390m overall, currently employs 96 people. Nominal plant capacity is 2,400 t/d, but the plant is generally run at around 105% of design capacity. With a planned turnaround every other year, on-stream time is reckoned at 8,000 hours per annum (333 days), giving an overall production of around 840,000 t/a. This represents around 25% of European methanol production capacity, or 13% of European consumption.

The plant is actually only 81.9% owned by Statoil, with the remaining 18.1% in the hands of Statoil’s partner Conoco, who also share the Heidrun field and associated pipeline.

Add to basket